Commit Graph

293 Commits

Author SHA1 Message Date
Fangrui Song efd94c56ba Use llvm::stable_sort
While touching the code, simplify if feasible.

llvm-svn: 358996
2019-04-23 14:51:27 +00:00
Tom Stellard 9ad714f7d1 Add support for pointer types in patterns
Summary:
This adds support for defining patterns for global isel using pointer
types, for example:

def : Pat<(load GPR32:$src),
          (p1 (LOAD GPR32:$src))>;

DAGISelEmitter will ignore the pointer information and treat these
types as integers with the same bit-width as the pointer type.

Reviewers: dsanders, rtereshin, arsenm

Reviewed By: arsenm

Subscribers: Petar.Avramovic, wdng, rovka, kristof.beyls, jfb, volkan, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57065

llvm-svn: 354510
2019-02-20 19:43:47 +00:00
Jessica Paquette 1ed1dd6d95 [GlobalISel] Skip patterns that define complex suboperands twice instead of dying
If we run into a pattern that looks like this:

add
  (complex $x, $y)
  (complex $x, $z)

We should skip the pattern instead of asserting/doing something unpredictable.

This makes us return an Error in that case, and adds a testcase for skipped
patterns.

Differential Revision: https://reviews.llvm.org/D57980

llvm-svn: 353586
2019-02-09 00:29:13 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Nicolai Haehnle 445b0b6260 TableGen/ISel: Allow PatFrag predicate code to access captured operands
Summary:
This simplifies writing predicates for pattern fragments that are
automatically re-associated or commuted.

For example, a followup patch adds patterns for fragments of the form
(add (shl $x, $y), $z) to the AMDGPU backend. Such patterns are
automatically commuted to (add $z, (shl $x, $y)), which makes it basically
impossible to refer to $x, $y, and $z generically in the PredicateCode.

With this change, the PredicateCode can refer to $x, $y, and $z simply
as `Operands[i]`.

Test confirmed that there are no changes to any of the generated files
when building all (non-experimental) targets.

Change-Id: I61c00ace7eed42c1d4edc4c5351174b56b77a79c

Reviewers: arsenm, rampitec, RKSimon, craig.topper, hfinkel, uweigand

Subscribers: wdng, tpr, llvm-commits

Differential Revision: https://reviews.llvm.org/D51994

llvm-svn: 347992
2018-11-30 14:15:13 +00:00
Fangrui Song 3507c6e884 Use the container form llvm::sort(C, ...)
There are a few leftovers in rL343163 which span two lines. This commit
changes these llvm::sort(C.begin(), C.end, ...) to llvm::sort(C, ...)

llvm-svn: 343426
2018-09-30 22:31:29 +00:00
Fangrui Song 0cac726a00 llvm::sort(C.begin(), C.end(), ...) -> llvm::sort(C, ...)
Summary: The convenience wrapper in STLExtras is available since rL342102.

Reviewers: dblaikie, javed.absar, JDevlieghere, andreadb

Subscribers: MatzeB, sanjoy, arsenm, dschuff, mehdi_amini, sdardis, nemanjai, jvesely, nhaehnle, sbc100, jgravelle-google, eraman, aheejin, kbarton, JDevlieghere, javed.absar, gbedwell, jrtc27, mgrang, atanasyan, steven_wu, george.burgess.iv, dexonsmith, kristina, jsji, llvm-commits

Differential Revision: https://reviews.llvm.org/D52573

llvm-svn: 343163
2018-09-27 02:13:45 +00:00
Daniel Sanders 06f4ff1952 [globalisel][tblgen] Table optimization should consider the C++ code in C++ predicates
This fixes PR39045

llvm-svn: 342997
2018-09-25 17:59:02 +00:00
Daniel Sanders f1e8e3b316 [globalisel] Remove dead code from GlobalISelEmitter
Summary: Found by GCC's -Wunused-function.

Patch by Kim Gräsman

Reviewers: ab, dsanders, llvm-commits

Reviewed By: dsanders

Subscribers: rovka, kristof.beyls

Differential Revision: https://reviews.llvm.org/D50611

llvm-svn: 339528
2018-08-12 21:49:42 +00:00
Andrei Elovikov 36cbbff48e [NFC] Prefer (void) to LLVM_ATTRIBUTE_UNUSED for unused var in GlobalISElemitter.cpp.
Reviewers: dsanders, craig.topper

Reviewed By: dsanders

Subscribers: rovka, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D48534

llvm-svn: 335581
2018-06-26 07:05:08 +00:00
Daniel Sanders 8ead1290e6 [globalisel][tablegen] Add support for C++ predicates on PatFrags and use it to support BFC on ARM.
So far, we've only handled special cases of PatFrag like ImmLeaf. This patch
adds support for the remaining cases using similar mechanisms.

Like most C++ code from SelectionDAG, GISel and DAGISel expect to operate on
different types and representations and as such the code is not compatible
between the two. It's therefore necessary to add an alternative implementation
in the GISelPredicateCode field.

The target test for this feature could easily be done with IntImmLeaf and this
would save on a little boilerplate. The reason I've chosen to implement this
using PatFrag.GISelPredicateCode and not IntImmLeaf is because I was unable to
find a rule that was blocked solely by lack of support for PatFrag predicates. I
found that the ones I investigated as being likely candidates for the test
were further blocked by other things.

llvm-svn: 334871
2018-06-15 23:13:43 +00:00
Florian Hahn 6b1db82acf Revert r334764, as it breaks some bots
llvm-svn: 334767
2018-06-14 20:32:58 +00:00
Florian Hahn 1b465767d6 [TableGen] Make TreePatternNode::getChild return a reference (NFC)
The return value of TreePatternNode::getChild is never null. This patch also
updates various places that use return values of getChild to also use
references. Those changes were suggested post-commit for D47463.

llvm-svn: 334764
2018-06-14 20:23:48 +00:00
Roman Tereshin a4c410d50d [GlobalISel][InstructionSelect] Switching over root LLTs, perf patch 10
This patch continues a series of patches started by r332907 (reapplied
as r332917).

In this commit we introduce new matching opcode for the MatchTable:
GIM_SwitchType, similar to GIM_SwitchOpcode, and use it to switch over
LLTs of def operands of root instructions on the 2nd level of the
MatchTable within GIM_SwitchOpcode's cases.

This is expected to decrease time GlobalISel spends in its
InstructionSelect pass by about 6.5% for an -O0 build as measured on
sqlite3-amalgamation (http://sqlite.org/download.html) targeting
AArch64 (cross-compile on x86).

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333146
2018-05-24 00:24:15 +00:00
Roman Tereshin 5f5e55008f [GlobalISel][InstructionSelect] Moving Reg Bank Checks forward, perf patch 9
This patch continues a series of patches started by r332907 (reapplied
as r332917).

In this commit we move register bank checks back from epilogue of
every rule matcher to a position locally close to the rest of the
checks for a particular (nested) instruction.

This increases the number of common conditions within 2nd level
groups.

This is expected to decrease time GlobalISel spends in its
InstructionSelect pass by about 2% for an -O0 build as measured on
sqlite3-amalgamation (http://sqlite.org/download.html) targeting
AArch64 (cross-compile on x86).

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333144
2018-05-23 23:58:10 +00:00
Roman Tereshin 152fc1605e [GlobalISel][InstructionSelect] Maximizing # of Group's common conditions, perf patch 8
This patch continues a series of patches started by r332907 (reapplied
as r332917).

In this commit we greedily stuff 2nd level GroupMatcher's common
conditions with as many predicates as possible. This is purely
post-processing and it doesn't change which rules are put into the
groups in the first place: that decision is made by looking at the
first common predicate only.

The compile time improvements are minor and well within error margin,
however, it's highly improbable that this transformation could
pessimize performance, thus I'm still committing it for potential
gains for targets not implementing GlobalISel yet and out of tree
targets.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333139
2018-05-23 22:50:53 +00:00
Roman Tereshin 9a9fa49cd2 [GlobalISel][InstructionSelect] Sorting MatchTable's 2nd level by root LLT, perf patch 7
This patch continues a series of patches started by r332907 (reapplied
as r332917).

In this commit we sort rules within their 2nd level by the type check
on def operand of the root instruction, which allows for better
nesting grouping on the level.

This is expected to decrease time GlobalISel spends in its
InstructionSelect pass by roughly 22% for an -O0 build as measured on
sqlite3-amalgamation (http://sqlite.org/download.html) targeting
AArch64 (cross-compile on x86).

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333131
2018-05-23 21:30:16 +00:00
Roman Tereshin b1ba127aa8 [GlobalISel][InstructionSelect] Moving type checks forward, perf patch 6
This patch continues a series of patches started by r332907 (reapplied
as r332917)

In this commit we sort type checks towards the beginning of every rule
within the MatchTable as they fail often and it's best to fail early.

This is expected to decrease time GlobalISel spends in its
InstructionSelect pass by roughly 7% for an -O0 build as measured on
sqlite3-amalgamation (http://sqlite.org/download.html) targeting
AArch64. The amalgamation is a large single-file C-source that makes
compiler backend performance improvements to stand out from frontend.
It's also a part of CTMark.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333114
2018-05-23 19:16:59 +00:00
Nicola Zaghen 03d0b91f43 Remove DEBUG macro.
Now that the LLVM_DEBUG() macro landed on the various sub-projects
the DEBUG macro can be removed.
Also change the new uses of DEBUG to LLVM_DEBUG.

Differential Revision: https://reviews.llvm.org/D46952

llvm-svn: 333091
2018-05-23 15:09:29 +00:00
Roman Tereshin fedae33efa [GlobalISel][InstructionSelect] MatchTable second level grouping, perf patch 5
This patch continues a series of patches started by r332907 (reapplied
as r332917)

In this commit we start grouping rules with common first condition on
the second level of the table.

This is expected to decrease time GlobalISel spends in its
InstructionSelect pass by roughly 13% for an -O0 build as measured on
sqlite3-amalgamation (http://sqlite.org/download.html) targeting
AArch64.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333053
2018-05-23 02:04:19 +00:00
Roman Tereshin 0ee082f3b9 [GlobalISel][InstructionSelect] Switching MatchTable over opcodes, perf patch 4
This patch continues a series of patches started by r332907 (reapplied
as r332917)

In this commit we introduce a new matching opcode GIM_SwitchOpcode
that implements a jump table over opcodes and start emitting them for
root instructions.

This is expected to decrease time GlobalISel spends in its
InstructionSelect pass by roughly 20% for an -O0 build as measured on
sqlite3-amalgamation (http://sqlite.org/download.html) targeting
AArch64.

To some degree, we assume here that the opcodes form a dense set,
which is true at the moment for all upstream targets given the
limitations of our rule importing mechanism.

It might not be true for out of tree targets, specifically due to
pseudo's. If so, we might noticeably increase the size of the
MatchTable with this patch due to padding zeros. This will be
addressed later.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333017
2018-05-22 19:37:59 +00:00
Roman Tereshin 7701360308 [GlobalISel][InstructionSelect] Sorting MatchTable's first level by opcodes and num operands, perf patch 3
This patch continues a series of patches started by r332907 (reapplied as r332917)

In this commit we start sorting the rules by the opcode first, and if
the same, by the number of operands of the root instructions. This
allows better grouping and safe as patterns with different opcodes are
mutually exclusive.

This is expected to decrease time GlobalISel spends in its
InstructionSelect pass by roughly 18% for an -O0 build as measured on
sqlite3-amalgamation (http://sqlite.org/download.html) targeting
AArch64.

I'm also removing RuleMatcher::getFirstConditionAsRootType() function
here and moving it to a later patch within the series as it's not used
yet and was causing a warning on sanitizer-ppc64le-linux bot.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 333001
2018-05-22 16:54:27 +00:00
Roman Tereshin dad5d6f347 Reverting 332999 to get it a proper commit message
llvm-svn: 333000
2018-05-22 16:53:42 +00:00
Roman Tereshin a7b5d45f9b diff --git a/utils/TableGen/GlobalISelEmitter.cpp b/utils/TableGen/GlobalISelEmitter.cpp
index cdc9df7bf6b..be08165a200 100644
--- a/utils/TableGen/GlobalISelEmitter.cpp
+++ b/utils/TableGen/GlobalISelEmitter.cpp
@@ -1,4531 +1,4539 @@
 //===- GlobalISelEmitter.cpp - Generate an instruction selector -----------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 /// \file
 /// This tablegen backend emits code for use by the GlobalISel instruction
 /// selector. See include/llvm/CodeGen/TargetGlobalISel.td.
 ///
 /// This file analyzes the patterns recognized by the SelectionDAGISel tablegen
 /// backend, filters out the ones that are unsupported, maps
 /// SelectionDAG-specific constructs to their GlobalISel counterpart
 /// (when applicable: MVT to LLT;  SDNode to generic Instruction).
 ///
 /// Not all patterns are supported: pass the tablegen invocation
 /// "-warn-on-skipped-patterns" to emit a warning when a pattern is skipped,
 /// as well as why.
 ///
 /// The generated file defines a single method:
 ///     bool <Target>InstructionSelector::selectImpl(MachineInstr &I) const;
 /// intended to be used in InstructionSelector::select as the first-step
 /// selector for the patterns that don't require complex C++.
 ///
 /// FIXME: We'll probably want to eventually define a base
 /// "TargetGenInstructionSelector" class.
 ///
 //===----------------------------------------------------------------------===//
 
 #include "CodeGenDAGPatterns.h"
 #include "SubtargetFeatureInfo.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallSet.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Support/CodeGenCoverage.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/LowLevelTypeImpl.h"
 #include "llvm/Support/MachineValueType.h"
 #include "llvm/Support/ScopedPrinter.h"
 #include "llvm/TableGen/Error.h"
 #include "llvm/TableGen/Record.h"
 #include "llvm/TableGen/TableGenBackend.h"
 #include <numeric>
 #include <string>
 using namespace llvm;
 
 #define DEBUG_TYPE "gisel-emitter"
 
 STATISTIC(NumPatternTotal, "Total number of patterns");
 STATISTIC(NumPatternImported, "Number of patterns imported from SelectionDAG");
 STATISTIC(NumPatternImportsSkipped, "Number of SelectionDAG imports skipped");
 STATISTIC(NumPatternsTested, "Number of patterns executed according to coverage information");
 STATISTIC(NumPatternEmitted, "Number of patterns emitted");
 
 cl::OptionCategory GlobalISelEmitterCat("Options for -gen-global-isel");
 
 static cl::opt<bool> WarnOnSkippedPatterns(
     "warn-on-skipped-patterns",
     cl::desc("Explain why a pattern was skipped for inclusion "
              "in the GlobalISel selector"),
     cl::init(false), cl::cat(GlobalISelEmitterCat));
 
 static cl::opt<bool> GenerateCoverage(
     "instrument-gisel-coverage",
     cl::desc("Generate coverage instrumentation for GlobalISel"),
     cl::init(false), cl::cat(GlobalISelEmitterCat));
 
 static cl::opt<std::string> UseCoverageFile(
     "gisel-coverage-file", cl::init(""),
     cl::desc("Specify file to retrieve coverage information from"),
     cl::cat(GlobalISelEmitterCat));
 
 static cl::opt<bool> OptimizeMatchTable(
     "optimize-match-table",
     cl::desc("Generate an optimized version of the match table"),
     cl::init(true), cl::cat(GlobalISelEmitterCat));
 
 namespace {
 //===- Helper functions ---------------------------------------------------===//
 
 /// Get the name of the enum value used to number the predicate function.
 std::string getEnumNameForPredicate(const TreePredicateFn &Predicate) {
   return "GIPFP_" + Predicate.getImmTypeIdentifier().str() + "_" +
          Predicate.getFnName();
 }
 
 /// Get the opcode used to check this predicate.
 std::string getMatchOpcodeForPredicate(const TreePredicateFn &Predicate) {
   return "GIM_Check" + Predicate.getImmTypeIdentifier().str() + "ImmPredicate";
 }
 
 /// This class stands in for LLT wherever we want to tablegen-erate an
 /// equivalent at compiler run-time.
 class LLTCodeGen {
 private:
   LLT Ty;
 
 public:
   LLTCodeGen() = default;
   LLTCodeGen(const LLT &Ty) : Ty(Ty) {}
 
   std::string getCxxEnumValue() const {
     std::string Str;
     raw_string_ostream OS(Str);
 
     emitCxxEnumValue(OS);
     return OS.str();
   }
 
   void emitCxxEnumValue(raw_ostream &OS) const {
     if (Ty.isScalar()) {
       OS << "GILLT_s" << Ty.getSizeInBits();
       return;
     }
     if (Ty.isVector()) {
       OS << "GILLT_v" << Ty.getNumElements() << "s" << Ty.getScalarSizeInBits();
       return;
     }
     if (Ty.isPointer()) {
       OS << "GILLT_p" << Ty.getAddressSpace();
       if (Ty.getSizeInBits() > 0)
         OS << "s" << Ty.getSizeInBits();
       return;
     }
     llvm_unreachable("Unhandled LLT");
   }
 
   void emitCxxConstructorCall(raw_ostream &OS) const {
     if (Ty.isScalar()) {
       OS << "LLT::scalar(" << Ty.getSizeInBits() << ")";
       return;
     }
     if (Ty.isVector()) {
       OS << "LLT::vector(" << Ty.getNumElements() << ", "
          << Ty.getScalarSizeInBits() << ")";
       return;
     }
     if (Ty.isPointer() && Ty.getSizeInBits() > 0) {
       OS << "LLT::pointer(" << Ty.getAddressSpace() << ", "
          << Ty.getSizeInBits() << ")";
       return;
     }
     llvm_unreachable("Unhandled LLT");
   }
 
   const LLT &get() const { return Ty; }
 
   /// This ordering is used for std::unique() and llvm::sort(). There's no
   /// particular logic behind the order but either A < B or B < A must be
   /// true if A != B.
   bool operator<(const LLTCodeGen &Other) const {
     if (Ty.isValid() != Other.Ty.isValid())
       return Ty.isValid() < Other.Ty.isValid();
     if (!Ty.isValid())
       return false;
 
     if (Ty.isVector() != Other.Ty.isVector())
       return Ty.isVector() < Other.Ty.isVector();
     if (Ty.isScalar() != Other.Ty.isScalar())
       return Ty.isScalar() < Other.Ty.isScalar();
     if (Ty.isPointer() != Other.Ty.isPointer())
       return Ty.isPointer() < Other.Ty.isPointer();
 
     if (Ty.isPointer() && Ty.getAddressSpace() != Other.Ty.getAddressSpace())
       return Ty.getAddressSpace() < Other.Ty.getAddressSpace();
 
     if (Ty.isVector() && Ty.getNumElements() != Other.Ty.getNumElements())
       return Ty.getNumElements() < Other.Ty.getNumElements();
 
     return Ty.getSizeInBits() < Other.Ty.getSizeInBits();
   }
 
   bool operator==(const LLTCodeGen &B) const { return Ty == B.Ty; }
 };
 
 // Track all types that are used so we can emit the corresponding enum.
 std::set<LLTCodeGen> KnownTypes;
 
 class InstructionMatcher;
 /// Convert an MVT to an equivalent LLT if possible, or the invalid LLT() for
 /// MVTs that don't map cleanly to an LLT (e.g., iPTR, *any, ...).
 static Optional<LLTCodeGen> MVTToLLT(MVT::SimpleValueType SVT) {
   MVT VT(SVT);
 
   if (VT.isVector() && VT.getVectorNumElements() != 1)
     return LLTCodeGen(
         LLT::vector(VT.getVectorNumElements(), VT.getScalarSizeInBits()));
 
   if (VT.isInteger() || VT.isFloatingPoint())
     return LLTCodeGen(LLT::scalar(VT.getSizeInBits()));
   return None;
 }
 
 static std::string explainPredicates(const TreePatternNode *N) {
   std::string Explanation = "";
   StringRef Separator = "";
   for (const auto &P : N->getPredicateFns()) {
     Explanation +=
         (Separator + P.getOrigPatFragRecord()->getRecord()->getName()).str();
     Separator = ", ";
 
     if (P.isAlwaysTrue())
       Explanation += " always-true";
     if (P.isImmediatePattern())
       Explanation += " immediate";
 
     if (P.isUnindexed())
       Explanation += " unindexed";
 
     if (P.isNonExtLoad())
       Explanation += " non-extload";
     if (P.isAnyExtLoad())
       Explanation += " extload";
     if (P.isSignExtLoad())
       Explanation += " sextload";
     if (P.isZeroExtLoad())
       Explanation += " zextload";
 
     if (P.isNonTruncStore())
       Explanation += " non-truncstore";
     if (P.isTruncStore())
       Explanation += " truncstore";
 
     if (Record *VT = P.getMemoryVT())
       Explanation += (" MemVT=" + VT->getName()).str();
     if (Record *VT = P.getScalarMemoryVT())
       Explanation += (" ScalarVT(MemVT)=" + VT->getName()).str();
 
     if (P.isAtomicOrderingMonotonic())
       Explanation += " monotonic";
     if (P.isAtomicOrderingAcquire())
       Explanation += " acquire";
     if (P.isAtomicOrderingRelease())
       Explanation += " release";
     if (P.isAtomicOrderingAcquireRelease())
       Explanation += " acq_rel";
     if (P.isAtomicOrderingSequentiallyConsistent())
       Explanation += " seq_cst";
     if (P.isAtomicOrderingAcquireOrStronger())
       Explanation += " >=acquire";
     if (P.isAtomicOrderingWeakerThanAcquire())
       Explanation += " <acquire";
     if (P.isAtomicOrderingReleaseOrStronger())
       Explanation += " >=release";
     if (P.isAtomicOrderingWeakerThanRelease())
       Explanation += " <release";
   }
   return Explanation;
 }
 
 std::string explainOperator(Record *Operator) {
   if (Operator->isSubClassOf("SDNode"))
     return (" (" + Operator->getValueAsString("Opcode") + ")").str();
 
   if (Operator->isSubClassOf("Intrinsic"))
     return (" (Operator is an Intrinsic, " + Operator->getName() + ")").str();
 
   if (Operator->isSubClassOf("ComplexPattern"))
     return (" (Operator is an unmapped ComplexPattern, " + Operator->getName() +
             ")")
         .str();
 
   if (Operator->isSubClassOf("SDNodeXForm"))
     return (" (Operator is an unmapped SDNodeXForm, " + Operator->getName() +
             ")")
         .str();
 
   return (" (Operator " + Operator->getName() + " not understood)").str();
 }
 
 /// Helper function to let the emitter report skip reason error messages.
 static Error failedImport(const Twine &Reason) {
   return make_error<StringError>(Reason, inconvertibleErrorCode());
 }
 
 static Error isTrivialOperatorNode(const TreePatternNode *N) {
   std::string Explanation = "";
   std::string Separator = "";
 
   bool HasUnsupportedPredicate = false;
   for (const auto &Predicate : N->getPredicateFns()) {
     if (Predicate.isAlwaysTrue())
       continue;
 
     if (Predicate.isImmediatePattern())
       continue;
 
     if (Predicate.isNonExtLoad() || Predicate.isAnyExtLoad() ||
         Predicate.isSignExtLoad() || Predicate.isZeroExtLoad())
       continue;
 
     if (Predicate.isNonTruncStore())
       continue;
 
     if (Predicate.isLoad() && Predicate.getMemoryVT())
       continue;
 
     if (Predicate.isLoad() || Predicate.isStore()) {
       if (Predicate.isUnindexed())
         continue;
     }
 
     if (Predicate.isAtomic() && Predicate.getMemoryVT())
       continue;
 
     if (Predicate.isAtomic() &&
         (Predicate.isAtomicOrderingMonotonic() ||
          Predicate.isAtomicOrderingAcquire() ||
          Predicate.isAtomicOrderingRelease() ||
          Predicate.isAtomicOrderingAcquireRelease() ||
          Predicate.isAtomicOrderingSequentiallyConsistent() ||
          Predicate.isAtomicOrderingAcquireOrStronger() ||
          Predicate.isAtomicOrderingWeakerThanAcquire() ||
          Predicate.isAtomicOrderingReleaseOrStronger() ||
          Predicate.isAtomicOrderingWeakerThanRelease()))
       continue;
 
     HasUnsupportedPredicate = true;
     Explanation = Separator + "Has a predicate (" + explainPredicates(N) + ")";
     Separator = ", ";
     Explanation += (Separator + "first-failing:" +
                     Predicate.getOrigPatFragRecord()->getRecord()->getName())
                        .str();
     break;
   }
 
   if (!HasUnsupportedPredicate)
     return Error::success();
 
   return failedImport(Explanation);
 }
 
 static Record *getInitValueAsRegClass(Init *V) {
   if (DefInit *VDefInit = dyn_cast<DefInit>(V)) {
     if (VDefInit->getDef()->isSubClassOf("RegisterOperand"))
       return VDefInit->getDef()->getValueAsDef("RegClass");
     if (VDefInit->getDef()->isSubClassOf("RegisterClass"))
       return VDefInit->getDef();
   }
   return nullptr;
 }
 
 std::string
 getNameForFeatureBitset(const std::vector<Record *> &FeatureBitset) {
   std::string Name = "GIFBS";
   for (const auto &Feature : FeatureBitset)
     Name += ("_" + Feature->getName()).str();
   return Name;
 }
 
 //===- MatchTable Helpers -------------------------------------------------===//
 
 class MatchTable;
 
 /// A record to be stored in a MatchTable.
 ///
 /// This class represents any and all output that may be required to emit the
 /// MatchTable. Instances  are most often configured to represent an opcode or
 /// value that will be emitted to the table with some formatting but it can also
 /// represent commas, comments, and other formatting instructions.
 struct MatchTableRecord {
   enum RecordFlagsBits {
     MTRF_None = 0x0,
     /// Causes EmitStr to be formatted as comment when emitted.
     MTRF_Comment = 0x1,
     /// Causes the record value to be followed by a comma when emitted.
     MTRF_CommaFollows = 0x2,
     /// Causes the record value to be followed by a line break when emitted.
     MTRF_LineBreakFollows = 0x4,
     /// Indicates that the record defines a label and causes an additional
     /// comment to be emitted containing the index of the label.
     MTRF_Label = 0x8,
     /// Causes the record to be emitted as the index of the label specified by
     /// LabelID along with a comment indicating where that label is.
     MTRF_JumpTarget = 0x10,
     /// Causes the formatter to add a level of indentation before emitting the
     /// record.
     MTRF_Indent = 0x20,
     /// Causes the formatter to remove a level of indentation after emitting the
     /// record.
     MTRF_Outdent = 0x40,
   };
 
   /// When MTRF_Label or MTRF_JumpTarget is used, indicates a label id to
   /// reference or define.
   unsigned LabelID;
   /// The string to emit. Depending on the MTRF_* flags it may be a comment, a
   /// value, a label name.
   std::string EmitStr;
 
 private:
   /// The number of MatchTable elements described by this record. Comments are 0
   /// while values are typically 1. Values >1 may occur when we need to emit
   /// values that exceed the size of a MatchTable element.
   unsigned NumElements;
 
 public:
   /// A bitfield of RecordFlagsBits flags.
   unsigned Flags;
 
   /// The actual run-time value, if known
   int64_t RawValue;
 
   MatchTableRecord(Optional<unsigned> LabelID_, StringRef EmitStr,
                    unsigned NumElements, unsigned Flags,
                    int64_t RawValue = std::numeric_limits<int64_t>::min())
       : LabelID(LabelID_.hasValue() ? LabelID_.getValue() : ~0u),
         EmitStr(EmitStr), NumElements(NumElements), Flags(Flags),
         RawValue(RawValue) {
 
     assert((!LabelID_.hasValue() || LabelID != ~0u) &&
            "This value is reserved for non-labels");
   }
   MatchTableRecord(const MatchTableRecord &Other) = default;
   MatchTableRecord(MatchTableRecord &&Other) = default;
 
   /// Useful if a Match Table Record gets optimized out
   void turnIntoComment() {
     Flags |= MTRF_Comment;
     Flags &= ~MTRF_CommaFollows;
     NumElements = 0;
   }
 
   /// For Jump Table generation purposes
   bool operator<(const MatchTableRecord &Other) const {
     return RawValue < Other.RawValue;
   }
   int64_t getRawValue() const { return RawValue; }
 
   void emit(raw_ostream &OS, bool LineBreakNextAfterThis,
             const MatchTable &Table) const;
   unsigned size() const { return NumElements; }
 };
 
 class Matcher;
 
 /// Holds the contents of a generated MatchTable to enable formatting and the
 /// necessary index tracking needed to support GIM_Try.
 class MatchTable {
   /// An unique identifier for the table. The generated table will be named
   /// MatchTable${ID}.
   unsigned ID;
   /// The records that make up the table. Also includes comments describing the
   /// values being emitted and line breaks to format it.
   std::vector<MatchTableRecord> Contents;
   /// The currently defined labels.
   DenseMap<unsigned, unsigned> LabelMap;
   /// Tracks the sum of MatchTableRecord::NumElements as the table is built.
   unsigned CurrentSize = 0;
   /// A unique identifier for a MatchTable label.
   unsigned CurrentLabelID = 0;
   /// Determines if the table should be instrumented for rule coverage tracking.
   bool IsWithCoverage;
 
 public:
   static MatchTableRecord LineBreak;
   static MatchTableRecord Comment(StringRef Comment) {
     return MatchTableRecord(None, Comment, 0, MatchTableRecord::MTRF_Comment);
   }
   static MatchTableRecord Opcode(StringRef Opcode, int IndentAdjust = 0) {
     unsigned ExtraFlags = 0;
     if (IndentAdjust > 0)
       ExtraFlags |= MatchTableRecord::MTRF_Indent;
     if (IndentAdjust < 0)
       ExtraFlags |= MatchTableRecord::MTRF_Outdent;
 
     return MatchTableRecord(None, Opcode, 1,
                             MatchTableRecord::MTRF_CommaFollows | ExtraFlags);
   }
   static MatchTableRecord NamedValue(StringRef NamedValue) {
     return MatchTableRecord(None, NamedValue, 1,
                             MatchTableRecord::MTRF_CommaFollows);
   }
   static MatchTableRecord NamedValue(StringRef NamedValue, int64_t RawValue) {
     return MatchTableRecord(None, NamedValue, 1,
                             MatchTableRecord::MTRF_CommaFollows, RawValue);
   }
   static MatchTableRecord NamedValue(StringRef Namespace,
                                      StringRef NamedValue) {
     return MatchTableRecord(None, (Namespace + "::" + NamedValue).str(), 1,
                             MatchTableRecord::MTRF_CommaFollows);
   }
   static MatchTableRecord NamedValue(StringRef Namespace, StringRef NamedValue,
                                      int64_t RawValue) {
     return MatchTableRecord(None, (Namespace + "::" + NamedValue).str(), 1,
                             MatchTableRecord::MTRF_CommaFollows, RawValue);
   }
   static MatchTableRecord IntValue(int64_t IntValue) {
     return MatchTableRecord(None, llvm::to_string(IntValue), 1,
                             MatchTableRecord::MTRF_CommaFollows);
   }
   static MatchTableRecord Label(unsigned LabelID) {
     return MatchTableRecord(LabelID, "Label " + llvm::to_string(LabelID), 0,
                             MatchTableRecord::MTRF_Label |
                                 MatchTableRecord::MTRF_Comment |
                                 MatchTableRecord::MTRF_LineBreakFollows);
   }
   static MatchTableRecord JumpTarget(unsigned LabelID) {
     return MatchTableRecord(LabelID, "Label " + llvm::to_string(LabelID), 1,
                             MatchTableRecord::MTRF_JumpTarget |
                                 MatchTableRecord::MTRF_Comment |
                                 MatchTableRecord::MTRF_CommaFollows);
   }
 
   static MatchTable buildTable(ArrayRef<Matcher *> Rules, bool WithCoverage);
 
   MatchTable(bool WithCoverage, unsigned ID = 0)
       : ID(ID), IsWithCoverage(WithCoverage) {}
 
   bool isWithCoverage() const { return IsWithCoverage; }
 
   void push_back(const MatchTableRecord &Value) {
     if (Value.Flags & MatchTableRecord::MTRF_Label)
       defineLabel(Value.LabelID);
     Contents.push_back(Value);
     CurrentSize += Value.size();
   }
 
   unsigned allocateLabelID() { return CurrentLabelID++; }
 
   void defineLabel(unsigned LabelID) {
     LabelMap.insert(std::make_pair(LabelID, CurrentSize));
   }
 
   unsigned getLabelIndex(unsigned LabelID) const {
     const auto I = LabelMap.find(LabelID);
     assert(I != LabelMap.end() && "Use of undeclared label");
     return I->second;
   }
 
   void emitUse(raw_ostream &OS) const { OS << "MatchTable" << ID; }
 
   void emitDeclaration(raw_ostream &OS) const {
     unsigned Indentation = 4;
     OS << "  constexpr static int64_t MatchTable" << ID << "[] = {";
     LineBreak.emit(OS, true, *this);
     OS << std::string(Indentation, ' ');
 
     for (auto I = Contents.begin(), E = Contents.end(); I != E;
          ++I) {
       bool LineBreakIsNext = false;
       const auto &NextI = std::next(I);
 
       if (NextI != E) {
         if (NextI->EmitStr == "" &&
             NextI->Flags == MatchTableRecord::MTRF_LineBreakFollows)
           LineBreakIsNext = true;
       }
 
       if (I->Flags & MatchTableRecord::MTRF_Indent)
         Indentation += 2;
 
       I->emit(OS, LineBreakIsNext, *this);
       if (I->Flags & MatchTableRecord::MTRF_LineBreakFollows)
         OS << std::string(Indentation, ' ');
 
       if (I->Flags & MatchTableRecord::MTRF_Outdent)
         Indentation -= 2;
     }
     OS << "};\n";
   }
 };
 
 MatchTableRecord MatchTable::LineBreak = {
     None, "" /* Emit String */, 0 /* Elements */,
     MatchTableRecord::MTRF_LineBreakFollows};
 
 void MatchTableRecord::emit(raw_ostream &OS, bool LineBreakIsNextAfterThis,
                             const MatchTable &Table) const {
   bool UseLineComment =
       LineBreakIsNextAfterThis | (Flags & MTRF_LineBreakFollows);
   if (Flags & (MTRF_JumpTarget | MTRF_CommaFollows))
     UseLineComment = false;
 
   if (Flags & MTRF_Comment)
     OS << (UseLineComment ? "// " : "/*");
 
   OS << EmitStr;
   if (Flags & MTRF_Label)
     OS << ": @" << Table.getLabelIndex(LabelID);
 
   if (Flags & MTRF_Comment && !UseLineComment)
     OS << "*/";
 
   if (Flags & MTRF_JumpTarget) {
     if (Flags & MTRF_Comment)
       OS << " ";
     OS << Table.getLabelIndex(LabelID);
   }
 
   if (Flags & MTRF_CommaFollows) {
     OS << ",";
     if (!LineBreakIsNextAfterThis && !(Flags & MTRF_LineBreakFollows))
       OS << " ";
   }
 
   if (Flags & MTRF_LineBreakFollows)
     OS << "\n";
 }
 
 MatchTable &operator<<(MatchTable &Table, const MatchTableRecord &Value) {
   Table.push_back(Value);
   return Table;
 }
 
 //===- Matchers -----------------------------------------------------------===//
 
 class OperandMatcher;
 class MatchAction;
 class PredicateMatcher;
 class RuleMatcher;
 
 class Matcher {
 public:
   virtual ~Matcher() = default;
   virtual void optimize() {}
   virtual void emit(MatchTable &Table) = 0;
 
   virtual bool hasFirstCondition() const = 0;
   virtual const PredicateMatcher &getFirstCondition() const = 0;
   virtual std::unique_ptr<PredicateMatcher> popFirstCondition() = 0;
 };
 
 MatchTable MatchTable::buildTable(ArrayRef<Matcher *> Rules,
                                   bool WithCoverage) {
   MatchTable Table(WithCoverage);
   for (Matcher *Rule : Rules)
     Rule->emit(Table);
 
   return Table << MatchTable::Opcode("GIM_Reject") << MatchTable::LineBreak;
 }
 
 class GroupMatcher final : public Matcher {
   /// Conditions that form a common prefix of all the matchers contained.
   SmallVector<std::unique_ptr<PredicateMatcher>, 1> Conditions;
 
   /// All the nested matchers, sharing a common prefix.
   std::vector<Matcher *> Matchers;
 
   /// An owning collection for any auxiliary matchers created while optimizing
   /// nested matchers contained.
   std::vector<std::unique_ptr<Matcher>> MatcherStorage;
 
 public:
   /// Add a matcher to the collection of nested matchers if it meets the
   /// requirements, and return true. If it doesn't, do nothing and return false.
   ///
   /// Expected to preserve its argument, so it could be moved out later on.
   bool addMatcher(Matcher &Candidate);
 
   /// Mark the matcher as fully-built and ensure any invariants expected by both
   /// optimize() and emit(...) methods. Generally, both sequences of calls
   /// are expected to lead to a sensible result:
   ///
   /// addMatcher(...)*; finalize(); optimize(); emit(...); and
   /// addMatcher(...)*; finalize(); emit(...);
   ///
   /// or generally
   ///
   /// addMatcher(...)*; finalize(); { optimize()*; emit(...); }*
   ///
   /// Multiple calls to optimize() are expected to be handled gracefully, though
   /// optimize() is not expected to be idempotent. Multiple calls to finalize()
   /// aren't generally supported. emit(...) is expected to be non-mutating and
   /// producing the exact same results upon repeated calls.
   ///
   /// addMatcher() calls after the finalize() call are not supported.
   ///
   /// finalize() and optimize() are both allowed to mutate the contained
   /// matchers, so moving them out after finalize() is not supported.
   void finalize();
   void optimize() override {}
   void emit(MatchTable &Table) override;
 
   /// Could be used to move out the matchers added previously, unless finalize()
   /// has been already called. If any of the matchers are moved out, the group
   /// becomes safe to destroy, but not safe to re-use for anything else.
   iterator_range<std::vector<Matcher *>::iterator> matchers() {
     return make_range(Matchers.begin(), Matchers.end());
   }
   size_t size() const { return Matchers.size(); }
   bool empty() const { return Matchers.empty(); }
 
   std::unique_ptr<PredicateMatcher> popFirstCondition() override {
     assert(!Conditions.empty() &&
            "Trying to pop a condition from a condition-less group");
     std::unique_ptr<PredicateMatcher> P = std::move(Conditions.front());
     Conditions.erase(Conditions.begin());
     return P;
   }
   const PredicateMatcher &getFirstCondition() const override {
     assert(!Conditions.empty() &&
            "Trying to get a condition from a condition-less group");
     return *Conditions.front();
   }
   bool hasFirstCondition() const override { return !Conditions.empty(); }
 
 private:
   /// See if a candidate matcher could be added to this group solely by
   /// analyzing its first condition.
   bool candidateConditionMatches(const PredicateMatcher &Predicate) const;
 };
 
 /// Generates code to check that a match rule matches.
 class RuleMatcher : public Matcher {
 public:
   using ActionList = std::list<std::unique_ptr<MatchAction>>;
   using action_iterator = ActionList::iterator;
 
 protected:
   /// A list of matchers that all need to succeed for the current rule to match.
   /// FIXME: This currently supports a single match position but could be
   /// extended to support multiple positions to support div/rem fusion or
   /// load-multiple instructions.
   using MatchersTy = std::vector<std::unique_ptr<InstructionMatcher>> ;
   MatchersTy Matchers;
 
   /// A list of actions that need to be taken when all predicates in this rule
   /// have succeeded.
   ActionList Actions;
 
   using DefinedInsnVariablesMap = std::map<InstructionMatcher *, unsigned>;
 
   /// A map of instruction matchers to the local variables
   DefinedInsnVariablesMap InsnVariableIDs;
 
   using MutatableInsnSet = SmallPtrSet<InstructionMatcher *, 4>;
 
   // The set of instruction matchers that have not yet been claimed for mutation
   // by a BuildMI.
   MutatableInsnSet MutatableInsns;
 
   /// A map of named operands defined by the matchers that may be referenced by
   /// the renderers.
   StringMap<OperandMatcher *> DefinedOperands;
 
   /// ID for the next instruction variable defined with implicitlyDefineInsnVar()
   unsigned NextInsnVarID;
 
   /// ID for the next output instruction allocated with allocateOutputInsnID()
   unsigned NextOutputInsnID;
 
   /// ID for the next temporary register ID allocated with allocateTempRegID()
   unsigned NextTempRegID;
 
   std::vector<Record *> RequiredFeatures;
   std::vector<std::unique_ptr<PredicateMatcher>> EpilogueMatchers;
 
   ArrayRef<SMLoc> SrcLoc;
 
   typedef std::tuple<Record *, unsigned, unsigned>
       DefinedComplexPatternSubOperand;
   typedef StringMap<DefinedComplexPatternSubOperand>
       DefinedComplexPatternSubOperandMap;
   /// A map of Symbolic Names to ComplexPattern sub-operands.
   DefinedComplexPatternSubOperandMap ComplexSubOperands;
 
   uint64_t RuleID;
   static uint64_t NextRuleID;
 
 public:
   RuleMatcher(ArrayRef<SMLoc> SrcLoc)
       : Matchers(), Actions(), InsnVariableIDs(), MutatableInsns(),
         DefinedOperands(), NextInsnVarID(0), NextOutputInsnID(0),
         NextTempRegID(0), SrcLoc(SrcLoc), ComplexSubOperands(),
         RuleID(NextRuleID++) {}
   RuleMatcher(RuleMatcher &&Other) = default;
   RuleMatcher &operator=(RuleMatcher &&Other) = default;
 
   uint64_t getRuleID() const { return RuleID; }
 
   InstructionMatcher &addInstructionMatcher(StringRef SymbolicName);
   void addRequiredFeature(Record *Feature);
   const std::vector<Record *> &getRequiredFeatures() const;
 
   template <class Kind, class... Args> Kind &addAction(Args &&... args);
   template <class Kind, class... Args>
   action_iterator insertAction(action_iterator InsertPt, Args &&... args);
 
   /// Define an instruction without emitting any code to do so.
   unsigned implicitlyDefineInsnVar(InstructionMatcher &Matcher);
 
   unsigned getInsnVarID(InstructionMatcher &InsnMatcher) const;
   DefinedInsnVariablesMap::const_iterator defined_insn_vars_begin() const {
     return InsnVariableIDs.begin();
   }
   DefinedInsnVariablesMap::const_iterator defined_insn_vars_end() const {
     return InsnVariableIDs.end();
   }
   iterator_range<typename DefinedInsnVariablesMap::const_iterator>
   defined_insn_vars() const {
     return make_range(defined_insn_vars_begin(), defined_insn_vars_end());
   }
 
   MutatableInsnSet::const_iterator mutatable_insns_begin() const {
     return MutatableInsns.begin();
   }
   MutatableInsnSet::const_iterator mutatable_insns_end() const {
     return MutatableInsns.end();
   }
   iterator_range<typename MutatableInsnSet::const_iterator>
   mutatable_insns() const {
     return make_range(mutatable_insns_begin(), mutatable_insns_end());
   }
   void reserveInsnMatcherForMutation(InstructionMatcher *InsnMatcher) {
     bool R = MutatableInsns.erase(InsnMatcher);
     assert(R && "Reserving a mutatable insn that isn't available");
     (void)R;
   }
 
   action_iterator actions_begin() { return Actions.begin(); }
   action_iterator actions_end() { return Actions.end(); }
   iterator_range<action_iterator> actions() {
     return make_range(actions_begin(), actions_end());
   }
 
   void defineOperand(StringRef SymbolicName, OperandMatcher &OM);
 
   void defineComplexSubOperand(StringRef SymbolicName, Record *ComplexPattern,
                                unsigned RendererID, unsigned SubOperandID) {
     assert(ComplexSubOperands.count(SymbolicName) == 0 && "Already defined");
     ComplexSubOperands[SymbolicName] =
         std::make_tuple(ComplexPattern, RendererID, SubOperandID);
   }
   Optional<DefinedComplexPatternSubOperand>
   getComplexSubOperand(StringRef SymbolicName) const {
     const auto &I = ComplexSubOperands.find(SymbolicName);
     if (I == ComplexSubOperands.end())
       return None;
     return I->second;
   }
 
   InstructionMatcher &getInstructionMatcher(StringRef SymbolicName) const;
   const OperandMatcher &getOperandMatcher(StringRef Name) const;
 
   void optimize() override;
   void emit(MatchTable &Table) override;
 
   /// Compare the priority of this object and B.
   ///
   /// Returns true if this object is more important than B.
   bool isHigherPriorityThan(const RuleMatcher &B) const;
 
   /// Report the maximum number of temporary operands needed by the rule
   /// matcher.
   unsigned countRendererFns() const;
 
   std::unique_ptr<PredicateMatcher> popFirstCondition() override;
   const PredicateMatcher &getFirstCondition() const override;
-  LLTCodeGen getFirstConditionAsRootType();
   bool hasFirstCondition() const override;
   unsigned getNumOperands() const;
   StringRef getOpcode() const;
 
   // FIXME: Remove this as soon as possible
   InstructionMatcher &insnmatchers_front() const { return *Matchers.front(); }
 
   unsigned allocateOutputInsnID() { return NextOutputInsnID++; }
   unsigned allocateTempRegID() { return NextTempRegID++; }
 
   iterator_range<MatchersTy::iterator> insnmatchers() {
     return make_range(Matchers.begin(), Matchers.end());
   }
   bool insnmatchers_empty() const { return Matchers.empty(); }
   void insnmatchers_pop_front() { Matchers.erase(Matchers.begin()); }
 };
 
 uint64_t RuleMatcher::NextRuleID = 0;
 
 using action_iterator = RuleMatcher::action_iterator;
 
 template <class PredicateTy> class PredicateListMatcher {
 private:
   /// Template instantiations should specialize this to return a string to use
   /// for the comment emitted when there are no predicates.
   std::string getNoPredicateComment() const;
 
 protected:
   using PredicatesTy = std::deque<std::unique_ptr<PredicateTy>>;
   PredicatesTy Predicates;
 
   /// Track if the list of predicates was manipulated by one of the optimization
   /// methods.
   bool Optimized = false;
 
 public:
   /// Construct a new predicate and add it to the matcher.
   template <class Kind, class... Args>
   Optional<Kind *> addPredicate(Args &&... args);
 
   typename PredicatesTy::iterator predicates_begin() {
     return Predicates.begin();
   }
   typename PredicatesTy::iterator predicates_end() {
     return Predicates.end();
   }
   iterator_range<typename PredicatesTy::iterator> predicates() {
     return make_range(predicates_begin(), predicates_end());
   }
   typename PredicatesTy::size_type predicates_size() const {
     return Predicates.size();
   }
   bool predicates_empty() const { return Predicates.empty(); }
 
   std::unique_ptr<PredicateTy> predicates_pop_front() {
     std::unique_ptr<PredicateTy> Front = std::move(Predicates.front());
     Predicates.pop_front();
     Optimized = true;
     return Front;
   }
 
   void prependPredicate(std::unique_ptr<PredicateTy> &&Predicate) {
     Predicates.push_front(std::move(Predicate));
   }
 
   void eraseNullPredicates() {
     const auto NewEnd =
         std::stable_partition(Predicates.begin(), Predicates.end(),
                               std::logical_not<std::unique_ptr<PredicateTy>>());
     if (NewEnd != Predicates.begin()) {
       Predicates.erase(Predicates.begin(), NewEnd);
       Optimized = true;
     }
   }
 
   /// Emit MatchTable opcodes that tests whether all the predicates are met.
   template <class... Args>
   void emitPredicateListOpcodes(MatchTable &Table, Args &&... args) {
     if (Predicates.empty() && !Optimized) {
       Table << MatchTable::Comment(getNoPredicateComment())
             << MatchTable::LineBreak;
       return;
     }
 
     for (const auto &Predicate : predicates())
       Predicate->emitPredicateOpcodes(Table, std::forward<Args>(args)...);
   }
 };
 
 class PredicateMatcher {
 public:
   /// This enum is used for RTTI and also defines the priority that is given to
   /// the predicate when generating the matcher code. Kinds with higher priority
   /// must be tested first.
   ///
   /// The relative priority of OPM_LLT, OPM_RegBank, and OPM_MBB do not matter
   /// but OPM_Int must have priority over OPM_RegBank since constant integers
   /// are represented by a virtual register defined by a G_CONSTANT instruction.
   ///
   /// Note: The relative priority between IPM_ and OPM_ does not matter, they
   /// are currently not compared between each other.
   enum PredicateKind {
     IPM_Opcode,
     IPM_NumOperands,
     IPM_ImmPredicate,
     IPM_AtomicOrderingMMO,
     IPM_MemoryLLTSize,
     IPM_MemoryVsLLTSize,
     OPM_SameOperand,
     OPM_ComplexPattern,
     OPM_IntrinsicID,
     OPM_Instruction,
     OPM_Int,
     OPM_LiteralInt,
     OPM_LLT,
     OPM_PointerToAny,
     OPM_RegBank,
     OPM_MBB,
   };
 
 protected:
   PredicateKind Kind;
   unsigned InsnVarID;
   unsigned OpIdx;
 
 public:
   PredicateMatcher(PredicateKind Kind, unsigned InsnVarID, unsigned OpIdx = ~0)
       : Kind(Kind), InsnVarID(InsnVarID), OpIdx(OpIdx) {}
 
   unsigned getInsnVarID() const { return InsnVarID; }
   unsigned getOpIdx() const { return OpIdx; }
 
   virtual ~PredicateMatcher() = default;
   /// Emit MatchTable opcodes that check the predicate for the given operand.
   virtual void emitPredicateOpcodes(MatchTable &Table,
                                     RuleMatcher &Rule) const = 0;
 
   PredicateKind getKind() const { return Kind; }
 
   virtual bool isIdentical(const PredicateMatcher &B) const {
     return B.getKind() == getKind() && InsnVarID == B.InsnVarID &&
            OpIdx == B.OpIdx;
   }
 
   virtual bool isIdenticalDownToValue(const PredicateMatcher &B) const {
     return hasValue() && PredicateMatcher::isIdentical(B);
   }
 
   virtual MatchTableRecord getValue() const {
     assert(hasValue() && "Can not get a value of a value-less predicate!");
     llvm_unreachable("Not implemented yet");
   }
   virtual bool hasValue() const { return false; }
 
   /// Report the maximum number of temporary operands needed by the predicate
   /// matcher.
   virtual unsigned countRendererFns() const { return 0; }
 };
 
 /// Generates code to check a predicate of an operand.
 ///
 /// Typical predicates include:
 /// * Operand is a particular register.
 /// * Operand is assigned a particular register bank.
 /// * Operand is an MBB.
 class OperandPredicateMatcher : public PredicateMatcher {
 public:
   OperandPredicateMatcher(PredicateKind Kind, unsigned InsnVarID,
                           unsigned OpIdx)
       : PredicateMatcher(Kind, InsnVarID, OpIdx) {}
   virtual ~OperandPredicateMatcher() {}
 
   /// Compare the priority of this object and B.
   ///
   /// Returns true if this object is more important than B.
   virtual bool isHigherPriorityThan(const OperandPredicateMatcher &B) const;
 };
 
 template <>
 std::string
 PredicateListMatcher<OperandPredicateMatcher>::getNoPredicateComment() const {
   return "No operand predicates";
 }
 
 /// Generates code to check that a register operand is defined by the same exact
 /// one as another.
 class SameOperandMatcher : public OperandPredicateMatcher {
   std::string MatchingName;
 
 public:
   SameOperandMatcher(unsigned InsnVarID, unsigned OpIdx, StringRef MatchingName)
       : OperandPredicateMatcher(OPM_SameOperand, InsnVarID, OpIdx),
         MatchingName(MatchingName) {}
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == OPM_SameOperand;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override;
 
   bool isIdentical(const PredicateMatcher &B) const override {
     return OperandPredicateMatcher::isIdentical(B) &&
            MatchingName == cast<SameOperandMatcher>(&B)->MatchingName;
   }
 };
 
 /// Generates code to check that an operand is a particular LLT.
 class LLTOperandMatcher : public OperandPredicateMatcher {
 protected:
   LLTCodeGen Ty;
 
 public:
   static std::map<LLTCodeGen, unsigned> TypeIDValues;
 
   static void initTypeIDValuesMap() {
     TypeIDValues.clear();
 
     unsigned ID = 0;
     for (const LLTCodeGen LLTy : KnownTypes)
       TypeIDValues[LLTy] = ID++;
   }
 
   LLTOperandMatcher(unsigned InsnVarID, unsigned OpIdx, const LLTCodeGen &Ty)
       : OperandPredicateMatcher(OPM_LLT, InsnVarID, OpIdx), Ty(Ty) {
     KnownTypes.insert(Ty);
   }
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == OPM_LLT;
   }
   bool isIdentical(const PredicateMatcher &B) const override {
     return OperandPredicateMatcher::isIdentical(B) &&
            Ty == cast<LLTOperandMatcher>(&B)->Ty;
   }
   MatchTableRecord getValue() const override {
     const auto VI = TypeIDValues.find(Ty);
     if (VI == TypeIDValues.end())
       return MatchTable::NamedValue(getTy().getCxxEnumValue());
     return MatchTable::NamedValue(getTy().getCxxEnumValue(), VI->second);
   }
   bool hasValue() const override {
     if (TypeIDValues.size() != KnownTypes.size())
       initTypeIDValuesMap();
     return TypeIDValues.count(Ty);
   }
 
   LLTCodeGen getTy() const { return Ty; }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIM_CheckType") << MatchTable::Comment("MI")
           << MatchTable::IntValue(InsnVarID) << MatchTable::Comment("Op")
           << MatchTable::IntValue(OpIdx) << MatchTable::Comment("Type")
           << getValue() << MatchTable::LineBreak;
   }
 };
 
 std::map<LLTCodeGen, unsigned> LLTOperandMatcher::TypeIDValues;
 
 /// Generates code to check that an operand is a pointer to any address space.
 ///
 /// In SelectionDAG, the types did not describe pointers or address spaces. As a
 /// result, iN is used to describe a pointer of N bits to any address space and
 /// PatFrag predicates are typically used to constrain the address space. There's
 /// no reliable means to derive the missing type information from the pattern so
 /// imported rules must test the components of a pointer separately.
 ///
 /// If SizeInBits is zero, then the pointer size will be obtained from the
 /// subtarget.
 class PointerToAnyOperandMatcher : public OperandPredicateMatcher {
 protected:
   unsigned SizeInBits;
 
 public:
   PointerToAnyOperandMatcher(unsigned InsnVarID, unsigned OpIdx,
                              unsigned SizeInBits)
       : OperandPredicateMatcher(OPM_PointerToAny, InsnVarID, OpIdx),
         SizeInBits(SizeInBits) {}
 
   static bool classof(const OperandPredicateMatcher *P) {
     return P->getKind() == OPM_PointerToAny;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIM_CheckPointerToAny")
           << MatchTable::Comment("MI") << MatchTable::IntValue(InsnVarID)
           << MatchTable::Comment("Op") << MatchTable::IntValue(OpIdx)
           << MatchTable::Comment("SizeInBits")
           << MatchTable::IntValue(SizeInBits) << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to check that an operand is a particular target constant.
 class ComplexPatternOperandMatcher : public OperandPredicateMatcher {
 protected:
   const OperandMatcher &Operand;
   const Record &TheDef;
 
   unsigned getAllocatedTemporariesBaseID() const;
 
 public:
   bool isIdentical(const PredicateMatcher &B) const override { return false; }
 
   ComplexPatternOperandMatcher(unsigned InsnVarID, unsigned OpIdx,
                                const OperandMatcher &Operand,
                                const Record &TheDef)
       : OperandPredicateMatcher(OPM_ComplexPattern, InsnVarID, OpIdx),
         Operand(Operand), TheDef(TheDef) {}
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == OPM_ComplexPattern;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     unsigned ID = getAllocatedTemporariesBaseID();
     Table << MatchTable::Opcode("GIM_CheckComplexPattern")
           << MatchTable::Comment("MI") << MatchTable::IntValue(InsnVarID)
           << MatchTable::Comment("Op") << MatchTable::IntValue(OpIdx)
           << MatchTable::Comment("Renderer") << MatchTable::IntValue(ID)
           << MatchTable::NamedValue(("GICP_" + TheDef.getName()).str())
           << MatchTable::LineBreak;
   }
 
   unsigned countRendererFns() const override {
     return 1;
   }
 };
 
 /// Generates code to check that an operand is in a particular register bank.
 class RegisterBankOperandMatcher : public OperandPredicateMatcher {
 protected:
   const CodeGenRegisterClass &RC;
 
 public:
   RegisterBankOperandMatcher(unsigned InsnVarID, unsigned OpIdx,
                              const CodeGenRegisterClass &RC)
       : OperandPredicateMatcher(OPM_RegBank, InsnVarID, OpIdx), RC(RC) {}
 
   bool isIdentical(const PredicateMatcher &B) const override {
     return OperandPredicateMatcher::isIdentical(B) &&
            RC.getDef() == cast<RegisterBankOperandMatcher>(&B)->RC.getDef();
   }
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == OPM_RegBank;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIM_CheckRegBankForClass")
           << MatchTable::Comment("MI") << MatchTable::IntValue(InsnVarID)
           << MatchTable::Comment("Op") << MatchTable::IntValue(OpIdx)
           << MatchTable::Comment("RC")
           << MatchTable::NamedValue(RC.getQualifiedName() + "RegClassID")
           << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to check that an operand is a basic block.
 class MBBOperandMatcher : public OperandPredicateMatcher {
 public:
   MBBOperandMatcher(unsigned InsnVarID, unsigned OpIdx)
       : OperandPredicateMatcher(OPM_MBB, InsnVarID, OpIdx) {}
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == OPM_MBB;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIM_CheckIsMBB") << MatchTable::Comment("MI")
           << MatchTable::IntValue(InsnVarID) << MatchTable::Comment("Op")
           << MatchTable::IntValue(OpIdx) << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to check that an operand is a G_CONSTANT with a particular
 /// int.
 class ConstantIntOperandMatcher : public OperandPredicateMatcher {
 protected:
   int64_t Value;
 
 public:
   ConstantIntOperandMatcher(unsigned InsnVarID, unsigned OpIdx, int64_t Value)
       : OperandPredicateMatcher(OPM_Int, InsnVarID, OpIdx), Value(Value) {}
 
   bool isIdentical(const PredicateMatcher &B) const override {
     return OperandPredicateMatcher::isIdentical(B) &&
            Value == cast<ConstantIntOperandMatcher>(&B)->Value;
   }
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == OPM_Int;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIM_CheckConstantInt")
           << MatchTable::Comment("MI") << MatchTable::IntValue(InsnVarID)
           << MatchTable::Comment("Op") << MatchTable::IntValue(OpIdx)
           << MatchTable::IntValue(Value) << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to check that an operand is a raw int (where MO.isImm() or
 /// MO.isCImm() is true).
 class LiteralIntOperandMatcher : public OperandPredicateMatcher {
 protected:
   int64_t Value;
 
 public:
   LiteralIntOperandMatcher(unsigned InsnVarID, unsigned OpIdx, int64_t Value)
       : OperandPredicateMatcher(OPM_LiteralInt, InsnVarID, OpIdx),
         Value(Value) {}
 
   bool isIdentical(const PredicateMatcher &B) const override {
     return OperandPredicateMatcher::isIdentical(B) &&
            Value == cast<LiteralIntOperandMatcher>(&B)->Value;
   }
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == OPM_LiteralInt;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIM_CheckLiteralInt")
           << MatchTable::Comment("MI") << MatchTable::IntValue(InsnVarID)
           << MatchTable::Comment("Op") << MatchTable::IntValue(OpIdx)
           << MatchTable::IntValue(Value) << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to check that an operand is an intrinsic ID.
 class IntrinsicIDOperandMatcher : public OperandPredicateMatcher {
 protected:
   const CodeGenIntrinsic *II;
 
 public:
   IntrinsicIDOperandMatcher(unsigned InsnVarID, unsigned OpIdx,
                             const CodeGenIntrinsic *II)
       : OperandPredicateMatcher(OPM_IntrinsicID, InsnVarID, OpIdx), II(II) {}
 
   bool isIdentical(const PredicateMatcher &B) const override {
     return OperandPredicateMatcher::isIdentical(B) &&
            II == cast<IntrinsicIDOperandMatcher>(&B)->II;
   }
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == OPM_IntrinsicID;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIM_CheckIntrinsicID")
           << MatchTable::Comment("MI") << MatchTable::IntValue(InsnVarID)
           << MatchTable::Comment("Op") << MatchTable::IntValue(OpIdx)
           << MatchTable::NamedValue("Intrinsic::" + II->EnumName)
           << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to check that a set of predicates match for a particular
 /// operand.
 class OperandMatcher : public PredicateListMatcher<OperandPredicateMatcher> {
 protected:
   InstructionMatcher &Insn;
   unsigned OpIdx;
   std::string SymbolicName;
 
   /// The index of the first temporary variable allocated to this operand. The
   /// number of allocated temporaries can be found with
   /// countRendererFns().
   unsigned AllocatedTemporariesBaseID;
 
 public:
   OperandMatcher(InstructionMatcher &Insn, unsigned OpIdx,
                  const std::string &SymbolicName,
                  unsigned AllocatedTemporariesBaseID)
       : Insn(Insn), OpIdx(OpIdx), SymbolicName(SymbolicName),
         AllocatedTemporariesBaseID(AllocatedTemporariesBaseID) {}
 
   bool hasSymbolicName() const { return !SymbolicName.empty(); }
   const StringRef getSymbolicName() const { return SymbolicName; }
   void setSymbolicName(StringRef Name) {
     assert(SymbolicName.empty() && "Operand already has a symbolic name");
     SymbolicName = Name;
   }
 
   /// Construct a new operand predicate and add it to the matcher.
   template <class Kind, class... Args>
   Optional<Kind *> addPredicate(Args &&... args) {
     if (isSameAsAnotherOperand())
       return None;
     Predicates.emplace_back(llvm::make_unique<Kind>(
         getInsnVarID(), getOpIdx(), std::forward<Args>(args)...));
     return static_cast<Kind *>(Predicates.back().get());
   }
 
   unsigned getOpIdx() const { return OpIdx; }
   unsigned getInsnVarID() const;
 
   std::string getOperandExpr(unsigned InsnVarID) const {
     return "State.MIs[" + llvm::to_string(InsnVarID) + "]->getOperand(" +
            llvm::to_string(OpIdx) + ")";
   }
 
   InstructionMatcher &getInstructionMatcher() const { return Insn; }
 
   Error addTypeCheckPredicate(const TypeSetByHwMode &VTy,
                               bool OperandIsAPointer);
 
   /// Emit MatchTable opcodes that test whether the instruction named in
   /// InsnVarID matches all the predicates and all the operands.
   void emitPredicateOpcodes(MatchTable &Table, RuleMatcher &Rule) {
     if (!Optimized) {
       std::string Comment;
       raw_string_ostream CommentOS(Comment);
       CommentOS << "MIs[" << getInsnVarID() << "] ";
       if (SymbolicName.empty())
         CommentOS << "Operand " << OpIdx;
       else
         CommentOS << SymbolicName;
       Table << MatchTable::Comment(CommentOS.str()) << MatchTable::LineBreak;
     }
 
     emitPredicateListOpcodes(Table, Rule);
   }
 
   /// Compare the priority of this object and B.
   ///
   /// Returns true if this object is more important than B.
   bool isHigherPriorityThan(OperandMatcher &B) {
     // Operand matchers involving more predicates have higher priority.
     if (predicates_size() > B.predicates_size())
       return true;
     if (predicates_size() < B.predicates_size())
       return false;
 
     // This assumes that predicates are added in a consistent order.
     for (auto &&Predicate : zip(predicates(), B.predicates())) {
       if (std::get<0>(Predicate)->isHigherPriorityThan(*std::get<1>(Predicate)))
         return true;
       if (std::get<1>(Predicate)->isHigherPriorityThan(*std::get<0>(Predicate)))
         return false;
     }
 
     return false;
   };
 
   /// Report the maximum number of temporary operands needed by the operand
   /// matcher.
   unsigned countRendererFns() {
     return std::accumulate(
         predicates().begin(), predicates().end(), 0,
         [](unsigned A,
            const std::unique_ptr<OperandPredicateMatcher> &Predicate) {
           return A + Predicate->countRendererFns();
         });
   }
 
   unsigned getAllocatedTemporariesBaseID() const {
     return AllocatedTemporariesBaseID;
   }
 
   bool isSameAsAnotherOperand() {
     for (const auto &Predicate : predicates())
       if (isa<SameOperandMatcher>(Predicate))
         return true;
     return false;
   }
 };
 
 Error OperandMatcher::addTypeCheckPredicate(const TypeSetByHwMode &VTy,
                                             bool OperandIsAPointer) {
   if (!VTy.isMachineValueType())
     return failedImport("unsupported typeset");
 
   if (VTy.getMachineValueType() == MVT::iPTR && OperandIsAPointer) {
     addPredicate<PointerToAnyOperandMatcher>(0);
     return Error::success();
   }
 
   auto OpTyOrNone = MVTToLLT(VTy.getMachineValueType().SimpleTy);
   if (!OpTyOrNone)
     return failedImport("unsupported type");
 
   if (OperandIsAPointer)
     addPredicate<PointerToAnyOperandMatcher>(OpTyOrNone->get().getSizeInBits());
   else
     addPredicate<LLTOperandMatcher>(*OpTyOrNone);
   return Error::success();
 }
 
 unsigned ComplexPatternOperandMatcher::getAllocatedTemporariesBaseID() const {
   return Operand.getAllocatedTemporariesBaseID();
 }
 
 /// Generates code to check a predicate on an instruction.
 ///
 /// Typical predicates include:
 /// * The opcode of the instruction is a particular value.
 /// * The nsw/nuw flag is/isn't set.
 class InstructionPredicateMatcher : public PredicateMatcher {
 public:
   InstructionPredicateMatcher(PredicateKind Kind, unsigned InsnVarID)
       : PredicateMatcher(Kind, InsnVarID) {}
   virtual ~InstructionPredicateMatcher() {}
 
   /// Compare the priority of this object and B.
   ///
   /// Returns true if this object is more important than B.
   virtual bool
   isHigherPriorityThan(const InstructionPredicateMatcher &B) const {
     return Kind < B.Kind;
   };
 };
 
 template <>
 std::string
 PredicateListMatcher<PredicateMatcher>::getNoPredicateComment() const {
   return "No instruction predicates";
 }
 
 /// Generates code to check the opcode of an instruction.
 class InstructionOpcodeMatcher : public InstructionPredicateMatcher {
 protected:
   const CodeGenInstruction *I;
 
   static DenseMap<const CodeGenInstruction *, unsigned> OpcodeValues;
 
 public:
   static void initOpcodeValuesMap(const CodeGenTarget &Target) {
     OpcodeValues.clear();
 
     unsigned OpcodeValue = 0;
     for (const CodeGenInstruction *I : Target.getInstructionsByEnumValue())
       OpcodeValues[I] = OpcodeValue++;
   }
 
   InstructionOpcodeMatcher(unsigned InsnVarID, const CodeGenInstruction *I)
       : InstructionPredicateMatcher(IPM_Opcode, InsnVarID), I(I) {}
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == IPM_Opcode;
   }
 
   bool isIdentical(const PredicateMatcher &B) const override {
     return InstructionPredicateMatcher::isIdentical(B) &&
            I == cast<InstructionOpcodeMatcher>(&B)->I;
   }
   MatchTableRecord getValue() const override {
     const auto VI = OpcodeValues.find(I);
     if (VI != OpcodeValues.end())
       return MatchTable::NamedValue(I->Namespace, I->TheDef->getName(),
                                     VI->second);
     return MatchTable::NamedValue(I->Namespace, I->TheDef->getName());
   }
   bool hasValue() const override { return OpcodeValues.count(I); }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIM_CheckOpcode") << MatchTable::Comment("MI")
           << MatchTable::IntValue(InsnVarID) << getValue()
           << MatchTable::LineBreak;
   }
 
   /// Compare the priority of this object and B.
   ///
   /// Returns true if this object is more important than B.
   bool
   isHigherPriorityThan(const InstructionPredicateMatcher &B) const override {
     if (InstructionPredicateMatcher::isHigherPriorityThan(B))
       return true;
     if (B.InstructionPredicateMatcher::isHigherPriorityThan(*this))
       return false;
 
     // Prioritize opcodes for cosmetic reasons in the generated source. Although
     // this is cosmetic at the moment, we may want to drive a similar ordering
     // using instruction frequency information to improve compile time.
     if (const InstructionOpcodeMatcher *BO =
             dyn_cast<InstructionOpcodeMatcher>(&B))
       return I->TheDef->getName() < BO->I->TheDef->getName();
 
     return false;
   };
 
   bool isConstantInstruction() const {
     return I->TheDef->getName() == "G_CONSTANT";
   }
 
   StringRef getOpcode() const { return I->TheDef->getName(); }
   unsigned getNumOperands() const { return I->Operands.size(); }
 
   StringRef getOperandType(unsigned OpIdx) const {
     return I->Operands[OpIdx].OperandType;
   }
 };
 
 DenseMap<const CodeGenInstruction *, unsigned>
     InstructionOpcodeMatcher::OpcodeValues;
 
 class InstructionNumOperandsMatcher final : public InstructionPredicateMatcher {
   unsigned NumOperands = 0;
 
 public:
   InstructionNumOperandsMatcher(unsigned InsnVarID, unsigned NumOperands)
       : InstructionPredicateMatcher(IPM_NumOperands, InsnVarID),
         NumOperands(NumOperands) {}
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == IPM_NumOperands;
   }
 
   bool isIdentical(const PredicateMatcher &B) const override {
     return InstructionPredicateMatcher::isIdentical(B) &&
            NumOperands == cast<InstructionNumOperandsMatcher>(&B)->NumOperands;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIM_CheckNumOperands")
           << MatchTable::Comment("MI") << MatchTable::IntValue(InsnVarID)
           << MatchTable::Comment("Expected")
           << MatchTable::IntValue(NumOperands) << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to check that this instruction is a constant whose value
 /// meets an immediate predicate.
 ///
 /// Immediates are slightly odd since they are typically used like an operand
 /// but are represented as an operator internally. We typically write simm8:$src
 /// in a tablegen pattern, but this is just syntactic sugar for
 /// (imm:i32)<<P:Predicate_simm8>>:$imm which more directly describes the nodes
 /// that will be matched and the predicate (which is attached to the imm
 /// operator) that will be tested. In SelectionDAG this describes a
 /// ConstantSDNode whose internal value will be tested using the simm8 predicate.
 ///
 /// The corresponding GlobalISel representation is %1 = G_CONSTANT iN Value. In
 /// this representation, the immediate could be tested with an
 /// InstructionMatcher, InstructionOpcodeMatcher, OperandMatcher, and a
 /// OperandPredicateMatcher-subclass to check the Value meets the predicate but
 /// there are two implementation issues with producing that matcher
 /// configuration from the SelectionDAG pattern:
 /// * ImmLeaf is a PatFrag whose root is an InstructionMatcher. This means that
 ///   were we to sink the immediate predicate to the operand we would have to
 ///   have two partial implementations of PatFrag support, one for immediates
 ///   and one for non-immediates.
 /// * At the point we handle the predicate, the OperandMatcher hasn't been
 ///   created yet. If we were to sink the predicate to the OperandMatcher we
 ///   would also have to complicate (or duplicate) the code that descends and
 ///   creates matchers for the subtree.
 /// Overall, it's simpler to handle it in the place it was found.
 class InstructionImmPredicateMatcher : public InstructionPredicateMatcher {
 protected:
   TreePredicateFn Predicate;
 
 public:
   InstructionImmPredicateMatcher(unsigned InsnVarID,
                                  const TreePredicateFn &Predicate)
       : InstructionPredicateMatcher(IPM_ImmPredicate, InsnVarID),
         Predicate(Predicate) {}
 
   bool isIdentical(const PredicateMatcher &B) const override {
     return InstructionPredicateMatcher::isIdentical(B) &&
            Predicate.getOrigPatFragRecord() ==
                cast<InstructionImmPredicateMatcher>(&B)
                    ->Predicate.getOrigPatFragRecord();
   }
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == IPM_ImmPredicate;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode(getMatchOpcodeForPredicate(Predicate))
           << MatchTable::Comment("MI") << MatchTable::IntValue(InsnVarID)
           << MatchTable::Comment("Predicate")
           << MatchTable::NamedValue(getEnumNameForPredicate(Predicate))
           << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to check that a memory instruction has a atomic ordering
 /// MachineMemoryOperand.
 class AtomicOrderingMMOPredicateMatcher : public InstructionPredicateMatcher {
 public:
   enum AOComparator {
     AO_Exactly,
     AO_OrStronger,
     AO_WeakerThan,
   };
 
 protected:
   StringRef Order;
   AOComparator Comparator;
 
 public:
   AtomicOrderingMMOPredicateMatcher(unsigned InsnVarID, StringRef Order,
                                     AOComparator Comparator = AO_Exactly)
       : InstructionPredicateMatcher(IPM_AtomicOrderingMMO, InsnVarID),
         Order(Order), Comparator(Comparator) {}
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == IPM_AtomicOrderingMMO;
   }
 
   bool isIdentical(const PredicateMatcher &B) const override {
     if (!InstructionPredicateMatcher::isIdentical(B))
       return false;
     const auto &R = *cast<AtomicOrderingMMOPredicateMatcher>(&B);
     return Order == R.Order && Comparator == R.Comparator;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     StringRef Opcode = "GIM_CheckAtomicOrdering";
 
     if (Comparator == AO_OrStronger)
       Opcode = "GIM_CheckAtomicOrderingOrStrongerThan";
     if (Comparator == AO_WeakerThan)
       Opcode = "GIM_CheckAtomicOrderingWeakerThan";
 
     Table << MatchTable::Opcode(Opcode) << MatchTable::Comment("MI")
           << MatchTable::IntValue(InsnVarID) << MatchTable::Comment("Order")
           << MatchTable::NamedValue(("(int64_t)AtomicOrdering::" + Order).str())
           << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to check that the size of an MMO is exactly N bytes.
 class MemorySizePredicateMatcher : public InstructionPredicateMatcher {
 protected:
   unsigned MMOIdx;
   uint64_t Size;
 
 public:
   MemorySizePredicateMatcher(unsigned InsnVarID, unsigned MMOIdx, unsigned Size)
       : InstructionPredicateMatcher(IPM_MemoryLLTSize, InsnVarID),
         MMOIdx(MMOIdx), Size(Size) {}
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == IPM_MemoryLLTSize;
   }
   bool isIdentical(const PredicateMatcher &B) const override {
     return InstructionPredicateMatcher::isIdentical(B) &&
            MMOIdx == cast<MemorySizePredicateMatcher>(&B)->MMOIdx &&
            Size == cast<MemorySizePredicateMatcher>(&B)->Size;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIM_CheckMemorySizeEqualTo")
           << MatchTable::Comment("MI") << MatchTable::IntValue(InsnVarID)
           << MatchTable::Comment("MMO") << MatchTable::IntValue(MMOIdx)
           << MatchTable::Comment("Size") << MatchTable::IntValue(Size)
           << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to check that the size of an MMO is less-than, equal-to, or
 /// greater than a given LLT.
 class MemoryVsLLTSizePredicateMatcher : public InstructionPredicateMatcher {
 public:
   enum RelationKind {
     GreaterThan,
     EqualTo,
     LessThan,
   };
 
 protected:
   unsigned MMOIdx;
   RelationKind Relation;
   unsigned OpIdx;
 
 public:
   MemoryVsLLTSizePredicateMatcher(unsigned InsnVarID, unsigned MMOIdx,
                                   enum RelationKind Relation,
                                   unsigned OpIdx)
       : InstructionPredicateMatcher(IPM_MemoryVsLLTSize, InsnVarID),
         MMOIdx(MMOIdx), Relation(Relation), OpIdx(OpIdx) {}
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == IPM_MemoryVsLLTSize;
   }
   bool isIdentical(const PredicateMatcher &B) const override {
     return InstructionPredicateMatcher::isIdentical(B) &&
            MMOIdx == cast<MemoryVsLLTSizePredicateMatcher>(&B)->MMOIdx &&
            Relation == cast<MemoryVsLLTSizePredicateMatcher>(&B)->Relation &&
            OpIdx == cast<MemoryVsLLTSizePredicateMatcher>(&B)->OpIdx;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode(Relation == EqualTo
                                     ? "GIM_CheckMemorySizeEqualToLLT"
                                     : Relation == GreaterThan
                                           ? "GIM_CheckMemorySizeGreaterThanLLT"
                                           : "GIM_CheckMemorySizeLessThanLLT")
           << MatchTable::Comment("MI") << MatchTable::IntValue(InsnVarID)
           << MatchTable::Comment("MMO") << MatchTable::IntValue(MMOIdx)
           << MatchTable::Comment("OpIdx") << MatchTable::IntValue(OpIdx)
           << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to check that a set of predicates and operands match for a
 /// particular instruction.
 ///
 /// Typical predicates include:
 /// * Has a specific opcode.
 /// * Has an nsw/nuw flag or doesn't.
 class InstructionMatcher final : public PredicateListMatcher<PredicateMatcher> {
 protected:
   typedef std::vector<std::unique_ptr<OperandMatcher>> OperandVec;
 
   RuleMatcher &Rule;
 
   /// The operands to match. All rendered operands must be present even if the
   /// condition is always true.
   OperandVec Operands;
   bool NumOperandsCheck = true;
 
   std::string SymbolicName;
   unsigned InsnVarID;
 
 public:
   InstructionMatcher(RuleMatcher &Rule, StringRef SymbolicName)
       : Rule(Rule), SymbolicName(SymbolicName) {
     // We create a new instruction matcher.
     // Get a new ID for that instruction.
     InsnVarID = Rule.implicitlyDefineInsnVar(*this);
   }
 
   /// Construct a new instruction predicate and add it to the matcher.
   template <class Kind, class... Args>
   Optional<Kind *> addPredicate(Args &&... args) {
     Predicates.emplace_back(
         llvm::make_unique<Kind>(getInsnVarID(), std::forward<Args>(args)...));
     return static_cast<Kind *>(Predicates.back().get());
   }
 
   RuleMatcher &getRuleMatcher() const { return Rule; }
 
   unsigned getInsnVarID() const { return InsnVarID; }
 
   /// Add an operand to the matcher.
   OperandMatcher &addOperand(unsigned OpIdx, const std::string &SymbolicName,
                              unsigned AllocatedTemporariesBaseID) {
     Operands.emplace_back(new OperandMatcher(*this, OpIdx, SymbolicName,
                                              AllocatedTemporariesBaseID));
     if (!SymbolicName.empty())
       Rule.defineOperand(SymbolicName, *Operands.back());
 
     return *Operands.back();
   }
 
   OperandMatcher &getOperand(unsigned OpIdx) {
     auto I = std::find_if(Operands.begin(), Operands.end(),
                           [&OpIdx](const std::unique_ptr<OperandMatcher> &X) {
                             return X->getOpIdx() == OpIdx;
                           });
     if (I != Operands.end())
       return **I;
     llvm_unreachable("Failed to lookup operand");
   }
 
   StringRef getSymbolicName() const { return SymbolicName; }
   unsigned getNumOperands() const { return Operands.size(); }
   OperandVec::iterator operands_begin() { return Operands.begin(); }
   OperandVec::iterator operands_end() { return Operands.end(); }
   iterator_range<OperandVec::iterator> operands() {
     return make_range(operands_begin(), operands_end());
   }
   OperandVec::const_iterator operands_begin() const { return Operands.begin(); }
   OperandVec::const_iterator operands_end() const { return Operands.end(); }
   iterator_range<OperandVec::const_iterator> operands() const {
     return make_range(operands_begin(), operands_end());
   }
   bool operands_empty() const { return Operands.empty(); }
 
   void pop_front() { Operands.erase(Operands.begin()); }
 
   void optimize();
 
   /// Emit MatchTable opcodes that test whether the instruction named in
   /// InsnVarName matches all the predicates and all the operands.
   void emitPredicateOpcodes(MatchTable &Table, RuleMatcher &Rule) {
     if (NumOperandsCheck)
       InstructionNumOperandsMatcher(InsnVarID, getNumOperands())
           .emitPredicateOpcodes(Table, Rule);
 
     emitPredicateListOpcodes(Table, Rule);
 
     for (const auto &Operand : Operands)
       Operand->emitPredicateOpcodes(Table, Rule);
   }
 
   /// Compare the priority of this object and B.
   ///
   /// Returns true if this object is more important than B.
   bool isHigherPriorityThan(InstructionMatcher &B) {
     // Instruction matchers involving more operands have higher priority.
     if (Operands.size() > B.Operands.size())
       return true;
     if (Operands.size() < B.Operands.size())
       return false;
 
     for (auto &&P : zip(predicates(), B.predicates())) {
       auto L = static_cast<InstructionPredicateMatcher *>(std::get<0>(P).get());
       auto R = static_cast<InstructionPredicateMatcher *>(std::get<1>(P).get());
       if (L->isHigherPriorityThan(*R))
         return true;
       if (R->isHigherPriorityThan(*L))
         return false;
     }
 
     for (const auto &Operand : zip(Operands, B.Operands)) {
       if (std::get<0>(Operand)->isHigherPriorityThan(*std::get<1>(Operand)))
         return true;
       if (std::get<1>(Operand)->isHigherPriorityThan(*std::get<0>(Operand)))
         return false;
     }
 
     return false;
   };
 
   /// Report the maximum number of temporary operands needed by the instruction
   /// matcher.
   unsigned countRendererFns() {
     return std::accumulate(
                predicates().begin(), predicates().end(), 0,
                [](unsigned A,
                   const std::unique_ptr<PredicateMatcher> &Predicate) {
                  return A + Predicate->countRendererFns();
                }) +
            std::accumulate(
                Operands.begin(), Operands.end(), 0,
                [](unsigned A, const std::unique_ptr<OperandMatcher> &Operand) {
                  return A + Operand->countRendererFns();
                });
   }
 
   InstructionOpcodeMatcher &getOpcodeMatcher() {
     for (auto &P : predicates())
       if (auto *OpMatcher = dyn_cast<InstructionOpcodeMatcher>(P.get()))
         return *OpMatcher;
     llvm_unreachable("Didn't find an opcode matcher");
   }
 
   bool isConstantInstruction() {
     return getOpcodeMatcher().isConstantInstruction();
   }
 
   StringRef getOpcode() { return getOpcodeMatcher().getOpcode(); }
 };
 
 StringRef RuleMatcher::getOpcode() const {
   return Matchers.front()->getOpcode();
 }
 
 unsigned RuleMatcher::getNumOperands() const {
   return Matchers.front()->getNumOperands();
 }
 
-LLTCodeGen RuleMatcher::getFirstConditionAsRootType() {
-  InstructionMatcher &InsnMatcher = *Matchers.front();
-  if (!InsnMatcher.predicates_empty())
-    if (const auto *TM =
-            dyn_cast<LLTOperandMatcher>(&**InsnMatcher.predicates_begin()))
-      if (TM->getInsnVarID() == 0 && TM->getOpIdx() == 0)
-        return TM->getTy();
-  return {};
-}
-
 /// Generates code to check that the operand is a register defined by an
 /// instruction that matches the given instruction matcher.
 ///
 /// For example, the pattern:
 ///   (set $dst, (G_MUL (G_ADD $src1, $src2), $src3))
 /// would use an InstructionOperandMatcher for operand 1 of the G_MUL to match
 /// the:
 ///   (G_ADD $src1, $src2)
 /// subpattern.
 class InstructionOperandMatcher : public OperandPredicateMatcher {
 protected:
   std::unique_ptr<InstructionMatcher> InsnMatcher;
 
 public:
   InstructionOperandMatcher(unsigned InsnVarID, unsigned OpIdx,
                             RuleMatcher &Rule, StringRef SymbolicName)
       : OperandPredicateMatcher(OPM_Instruction, InsnVarID, OpIdx),
         InsnMatcher(new InstructionMatcher(Rule, SymbolicName)) {}
 
   static bool classof(const PredicateMatcher *P) {
     return P->getKind() == OPM_Instruction;
   }
 
   InstructionMatcher &getInsnMatcher() const { return *InsnMatcher; }
 
   void emitCaptureOpcodes(MatchTable &Table, RuleMatcher &Rule) const {
     const unsigned NewInsnVarID = InsnMatcher->getInsnVarID();
     Table << MatchTable::Opcode("GIM_RecordInsn")
           << MatchTable::Comment("DefineMI")
           << MatchTable::IntValue(NewInsnVarID) << MatchTable::Comment("MI")
           << MatchTable::IntValue(getInsnVarID())
           << MatchTable::Comment("OpIdx") << MatchTable::IntValue(getOpIdx())
           << MatchTable::Comment("MIs[" + llvm::to_string(NewInsnVarID) + "]")
           << MatchTable::LineBreak;
   }
 
   void emitPredicateOpcodes(MatchTable &Table,
                             RuleMatcher &Rule) const override {
     emitCaptureOpcodes(Table, Rule);
     InsnMatcher->emitPredicateOpcodes(Table, Rule);
   }
 
   bool isHigherPriorityThan(const OperandPredicateMatcher &B) const override {
     if (OperandPredicateMatcher::isHigherPriorityThan(B))
       return true;
     if (B.OperandPredicateMatcher::isHigherPriorityThan(*this))
       return false;
 
     if (const InstructionOperandMatcher *BP =
             dyn_cast<InstructionOperandMatcher>(&B))
       if (InsnMatcher->isHigherPriorityThan(*BP->InsnMatcher))
         return true;
     return false;
   }
 };
 
 void InstructionMatcher::optimize() {
   SmallVector<std::unique_ptr<PredicateMatcher>, 8> Stash;
   const auto &OpcMatcher = getOpcodeMatcher();
 
   Stash.push_back(predicates_pop_front());
   if (Stash.back().get() == &OpcMatcher) {
     if (NumOperandsCheck && OpcMatcher.getNumOperands() < getNumOperands())
       Stash.emplace_back(
           new InstructionNumOperandsMatcher(InsnVarID, getNumOperands()));
     NumOperandsCheck = false;
   }
 
   if (InsnVarID > 0) {
     assert(!Operands.empty() && "Nested instruction is expected to def a vreg");
     for (auto &OP : Operands[0]->predicates())
       OP.reset();
     Operands[0]->eraseNullPredicates();
   }
   while (!Stash.empty())
     prependPredicate(Stash.pop_back_val());
 }
 
 //===- Actions ------------------------------------------------------------===//
 class OperandRenderer {
 public:
   enum RendererKind {
     OR_Copy,
     OR_CopyOrAddZeroReg,
     OR_CopySubReg,
     OR_CopyConstantAsImm,
     OR_CopyFConstantAsFPImm,
     OR_Imm,
     OR_Register,
     OR_TempRegister,
     OR_ComplexPattern,
     OR_Custom
   };
 
 protected:
   RendererKind Kind;
 
 public:
   OperandRenderer(RendererKind Kind) : Kind(Kind) {}
   virtual ~OperandRenderer() {}
 
   RendererKind getKind() const { return Kind; }
 
   virtual void emitRenderOpcodes(MatchTable &Table,
                                  RuleMatcher &Rule) const = 0;
 };
 
 /// A CopyRenderer emits code to copy a single operand from an existing
 /// instruction to the one being built.
 class CopyRenderer : public OperandRenderer {
 protected:
   unsigned NewInsnID;
   /// The name of the operand.
   const StringRef SymbolicName;
 
 public:
   CopyRenderer(unsigned NewInsnID, StringRef SymbolicName)
       : OperandRenderer(OR_Copy), NewInsnID(NewInsnID),
         SymbolicName(SymbolicName) {
     assert(!SymbolicName.empty() && "Cannot copy from an unspecified source");
   }
 
   static bool classof(const OperandRenderer *R) {
     return R->getKind() == OR_Copy;
   }
 
   const StringRef getSymbolicName() const { return SymbolicName; }
 
   void emitRenderOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     const OperandMatcher &Operand = Rule.getOperandMatcher(SymbolicName);
     unsigned OldInsnVarID = Rule.getInsnVarID(Operand.getInstructionMatcher());
     Table << MatchTable::Opcode("GIR_Copy") << MatchTable::Comment("NewInsnID")
           << MatchTable::IntValue(NewInsnID) << MatchTable::Comment("OldInsnID")
           << MatchTable::IntValue(OldInsnVarID) << MatchTable::Comment("OpIdx")
           << MatchTable::IntValue(Operand.getOpIdx())
           << MatchTable::Comment(SymbolicName) << MatchTable::LineBreak;
   }
 };
 
 /// A CopyOrAddZeroRegRenderer emits code to copy a single operand from an
 /// existing instruction to the one being built. If the operand turns out to be
 /// a 'G_CONSTANT 0' then it replaces the operand with a zero register.
 class CopyOrAddZeroRegRenderer : public OperandRenderer {
 protected:
   unsigned NewInsnID;
   /// The name of the operand.
   const StringRef SymbolicName;
   const Record *ZeroRegisterDef;
 
 public:
   CopyOrAddZeroRegRenderer(unsigned NewInsnID,
                            StringRef SymbolicName, Record *ZeroRegisterDef)
       : OperandRenderer(OR_CopyOrAddZeroReg), NewInsnID(NewInsnID),
         SymbolicName(SymbolicName), ZeroRegisterDef(ZeroRegisterDef) {
     assert(!SymbolicName.empty() && "Cannot copy from an unspecified source");
   }
 
   static bool classof(const OperandRenderer *R) {
     return R->getKind() == OR_CopyOrAddZeroReg;
   }
 
   const StringRef getSymbolicName() const { return SymbolicName; }
 
   void emitRenderOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     const OperandMatcher &Operand = Rule.getOperandMatcher(SymbolicName);
     unsigned OldInsnVarID = Rule.getInsnVarID(Operand.getInstructionMatcher());
     Table << MatchTable::Opcode("GIR_CopyOrAddZeroReg")
           << MatchTable::Comment("NewInsnID") << MatchTable::IntValue(NewInsnID)
           << MatchTable::Comment("OldInsnID")
           << MatchTable::IntValue(OldInsnVarID) << MatchTable::Comment("OpIdx")
           << MatchTable::IntValue(Operand.getOpIdx())
           << MatchTable::NamedValue(
                  (ZeroRegisterDef->getValue("Namespace")
                       ? ZeroRegisterDef->getValueAsString("Namespace")
                       : ""),
                  ZeroRegisterDef->getName())
           << MatchTable::Comment(SymbolicName) << MatchTable::LineBreak;
   }
 };
 
 /// A CopyConstantAsImmRenderer emits code to render a G_CONSTANT instruction to
 /// an extended immediate operand.
 class CopyConstantAsImmRenderer : public OperandRenderer {
 protected:
   unsigned NewInsnID;
   /// The name of the operand.
   const std::string SymbolicName;
   bool Signed;
 
 public:
   CopyConstantAsImmRenderer(unsigned NewInsnID, StringRef SymbolicName)
       : OperandRenderer(OR_CopyConstantAsImm), NewInsnID(NewInsnID),
         SymbolicName(SymbolicName), Signed(true) {}
 
   static bool classof(const OperandRenderer *R) {
     return R->getKind() == OR_CopyConstantAsImm;
   }
 
   const StringRef getSymbolicName() const { return SymbolicName; }
 
   void emitRenderOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     InstructionMatcher &InsnMatcher = Rule.getInstructionMatcher(SymbolicName);
     unsigned OldInsnVarID = Rule.getInsnVarID(InsnMatcher);
     Table << MatchTable::Opcode(Signed ? "GIR_CopyConstantAsSImm"
                                        : "GIR_CopyConstantAsUImm")
           << MatchTable::Comment("NewInsnID") << MatchTable::IntValue(NewInsnID)
           << MatchTable::Comment("OldInsnID")
           << MatchTable::IntValue(OldInsnVarID)
           << MatchTable::Comment(SymbolicName) << MatchTable::LineBreak;
   }
 };
 
 /// A CopyFConstantAsFPImmRenderer emits code to render a G_FCONSTANT
 /// instruction to an extended immediate operand.
 class CopyFConstantAsFPImmRenderer : public OperandRenderer {
 protected:
   unsigned NewInsnID;
   /// The name of the operand.
   const std::string SymbolicName;
 
 public:
   CopyFConstantAsFPImmRenderer(unsigned NewInsnID, StringRef SymbolicName)
       : OperandRenderer(OR_CopyFConstantAsFPImm), NewInsnID(NewInsnID),
         SymbolicName(SymbolicName) {}
 
   static bool classof(const OperandRenderer *R) {
     return R->getKind() == OR_CopyFConstantAsFPImm;
   }
 
   const StringRef getSymbolicName() const { return SymbolicName; }
 
   void emitRenderOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     InstructionMatcher &InsnMatcher = Rule.getInstructionMatcher(SymbolicName);
     unsigned OldInsnVarID = Rule.getInsnVarID(InsnMatcher);
     Table << MatchTable::Opcode("GIR_CopyFConstantAsFPImm")
           << MatchTable::Comment("NewInsnID") << MatchTable::IntValue(NewInsnID)
           << MatchTable::Comment("OldInsnID")
           << MatchTable::IntValue(OldInsnVarID)
           << MatchTable::Comment(SymbolicName) << MatchTable::LineBreak;
   }
 };
 
 /// A CopySubRegRenderer emits code to copy a single register operand from an
 /// existing instruction to the one being built and indicate that only a
 /// subregister should be copied.
 class CopySubRegRenderer : public OperandRenderer {
 protected:
   unsigned NewInsnID;
   /// The name of the operand.
   const StringRef SymbolicName;
   /// The subregister to extract.
   const CodeGenSubRegIndex *SubReg;
 
 public:
   CopySubRegRenderer(unsigned NewInsnID, StringRef SymbolicName,
                      const CodeGenSubRegIndex *SubReg)
       : OperandRenderer(OR_CopySubReg), NewInsnID(NewInsnID),
         SymbolicName(SymbolicName), SubReg(SubReg) {}
 
   static bool classof(const OperandRenderer *R) {
     return R->getKind() == OR_CopySubReg;
   }
 
   const StringRef getSymbolicName() const { return SymbolicName; }
 
   void emitRenderOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     const OperandMatcher &Operand = Rule.getOperandMatcher(SymbolicName);
     unsigned OldInsnVarID = Rule.getInsnVarID(Operand.getInstructionMatcher());
     Table << MatchTable::Opcode("GIR_CopySubReg")
           << MatchTable::Comment("NewInsnID") << MatchTable::IntValue(NewInsnID)
           << MatchTable::Comment("OldInsnID")
           << MatchTable::IntValue(OldInsnVarID) << MatchTable::Comment("OpIdx")
           << MatchTable::IntValue(Operand.getOpIdx())
           << MatchTable::Comment("SubRegIdx")
           << MatchTable::IntValue(SubReg->EnumValue)
           << MatchTable::Comment(SymbolicName) << MatchTable::LineBreak;
   }
 };
 
 /// Adds a specific physical register to the instruction being built.
 /// This is typically useful for WZR/XZR on AArch64.
 class AddRegisterRenderer : public OperandRenderer {
 protected:
   unsigned InsnID;
   const Record *RegisterDef;
 
 public:
   AddRegisterRenderer(unsigned InsnID, const Record *RegisterDef)
       : OperandRenderer(OR_Register), InsnID(InsnID), RegisterDef(RegisterDef) {
   }
 
   static bool classof(const OperandRenderer *R) {
     return R->getKind() == OR_Register;
   }
 
   void emitRenderOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIR_AddRegister")
           << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
           << MatchTable::NamedValue(
                  (RegisterDef->getValue("Namespace")
                       ? RegisterDef->getValueAsString("Namespace")
                       : ""),
                  RegisterDef->getName())
           << MatchTable::LineBreak;
   }
 };
 
 /// Adds a specific temporary virtual register to the instruction being built.
 /// This is used to chain instructions together when emitting multiple
 /// instructions.
 class TempRegRenderer : public OperandRenderer {
 protected:
   unsigned InsnID;
   unsigned TempRegID;
   bool IsDef;
 
 public:
   TempRegRenderer(unsigned InsnID, unsigned TempRegID, bool IsDef = false)
       : OperandRenderer(OR_Register), InsnID(InsnID), TempRegID(TempRegID),
         IsDef(IsDef) {}
 
   static bool classof(const OperandRenderer *R) {
     return R->getKind() == OR_TempRegister;
   }
 
   void emitRenderOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIR_AddTempRegister")
           << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
           << MatchTable::Comment("TempRegID") << MatchTable::IntValue(TempRegID)
           << MatchTable::Comment("TempRegFlags");
     if (IsDef)
       Table << MatchTable::NamedValue("RegState::Define");
     else
       Table << MatchTable::IntValue(0);
     Table << MatchTable::LineBreak;
   }
 };
 
 /// Adds a specific immediate to the instruction being built.
 class ImmRenderer : public OperandRenderer {
 protected:
   unsigned InsnID;
   int64_t Imm;
 
 public:
   ImmRenderer(unsigned InsnID, int64_t Imm)
       : OperandRenderer(OR_Imm), InsnID(InsnID), Imm(Imm) {}
 
   static bool classof(const OperandRenderer *R) {
     return R->getKind() == OR_Imm;
   }
 
   void emitRenderOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIR_AddImm") << MatchTable::Comment("InsnID")
           << MatchTable::IntValue(InsnID) << MatchTable::Comment("Imm")
           << MatchTable::IntValue(Imm) << MatchTable::LineBreak;
   }
 };
 
 /// Adds operands by calling a renderer function supplied by the ComplexPattern
 /// matcher function.
 class RenderComplexPatternOperand : public OperandRenderer {
 private:
   unsigned InsnID;
   const Record &TheDef;
   /// The name of the operand.
   const StringRef SymbolicName;
   /// The renderer number. This must be unique within a rule since it's used to
   /// identify a temporary variable to hold the renderer function.
   unsigned RendererID;
   /// When provided, this is the suboperand of the ComplexPattern operand to
   /// render. Otherwise all the suboperands will be rendered.
   Optional<unsigned> SubOperand;
 
   unsigned getNumOperands() const {
     return TheDef.getValueAsDag("Operands")->getNumArgs();
   }
 
 public:
   RenderComplexPatternOperand(unsigned InsnID, const Record &TheDef,
                               StringRef SymbolicName, unsigned RendererID,
                               Optional<unsigned> SubOperand = None)
       : OperandRenderer(OR_ComplexPattern), InsnID(InsnID), TheDef(TheDef),
         SymbolicName(SymbolicName), RendererID(RendererID),
         SubOperand(SubOperand) {}
 
   static bool classof(const OperandRenderer *R) {
     return R->getKind() == OR_ComplexPattern;
   }
 
   void emitRenderOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode(SubOperand.hasValue() ? "GIR_ComplexSubOperandRenderer"
                                                       : "GIR_ComplexRenderer")
           << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
           << MatchTable::Comment("RendererID")
           << MatchTable::IntValue(RendererID);
     if (SubOperand.hasValue())
       Table << MatchTable::Comment("SubOperand")
             << MatchTable::IntValue(SubOperand.getValue());
     Table << MatchTable::Comment(SymbolicName) << MatchTable::LineBreak;
   }
 };
 
 class CustomRenderer : public OperandRenderer {
 protected:
   unsigned InsnID;
   const Record &Renderer;
   /// The name of the operand.
   const std::string SymbolicName;
 
 public:
   CustomRenderer(unsigned InsnID, const Record &Renderer,
                  StringRef SymbolicName)
       : OperandRenderer(OR_Custom), InsnID(InsnID), Renderer(Renderer),
         SymbolicName(SymbolicName) {}
 
   static bool classof(const OperandRenderer *R) {
     return R->getKind() == OR_Custom;
   }
 
   void emitRenderOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     InstructionMatcher &InsnMatcher = Rule.getInstructionMatcher(SymbolicName);
     unsigned OldInsnVarID = Rule.getInsnVarID(InsnMatcher);
     Table << MatchTable::Opcode("GIR_CustomRenderer")
           << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
           << MatchTable::Comment("OldInsnID")
           << MatchTable::IntValue(OldInsnVarID)
           << MatchTable::Comment("Renderer")
           << MatchTable::NamedValue(
                  "GICR_" + Renderer.getValueAsString("RendererFn").str())
           << MatchTable::Comment(SymbolicName) << MatchTable::LineBreak;
   }
 };
 
 /// An action taken when all Matcher predicates succeeded for a parent rule.
 ///
 /// Typical actions include:
 /// * Changing the opcode of an instruction.
 /// * Adding an operand to an instruction.
 class MatchAction {
 public:
   virtual ~MatchAction() {}
 
   /// Emit the MatchTable opcodes to implement the action.
   virtual void emitActionOpcodes(MatchTable &Table,
                                  RuleMatcher &Rule) const = 0;
 };
 
 /// Generates a comment describing the matched rule being acted upon.
 class DebugCommentAction : public MatchAction {
 private:
   std::string S;
 
 public:
   DebugCommentAction(StringRef S) : S(S) {}
 
   void emitActionOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     Table << MatchTable::Comment(S) << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to build an instruction or mutate an existing instruction
 /// into the desired instruction when this is possible.
 class BuildMIAction : public MatchAction {
 private:
   unsigned InsnID;
   const CodeGenInstruction *I;
   InstructionMatcher *Matched;
   std::vector<std::unique_ptr<OperandRenderer>> OperandRenderers;
 
   /// True if the instruction can be built solely by mutating the opcode.
   bool canMutate(RuleMatcher &Rule, const InstructionMatcher *Insn) const {
     if (!Insn)
       return false;
 
     if (OperandRenderers.size() != Insn->getNumOperands())
       return false;
 
     for (const auto &Renderer : enumerate(OperandRenderers)) {
       if (const auto *Copy = dyn_cast<CopyRenderer>(&*Renderer.value())) {
         const OperandMatcher &OM = Rule.getOperandMatcher(Copy->getSymbolicName());
         if (Insn != &OM.getInstructionMatcher() ||
             OM.getOpIdx() != Renderer.index())
           return false;
       } else
         return false;
     }
 
     return true;
   }
 
 public:
   BuildMIAction(unsigned InsnID, const CodeGenInstruction *I)
       : InsnID(InsnID), I(I), Matched(nullptr) {}
 
   unsigned getInsnID() const { return InsnID; }
   const CodeGenInstruction *getCGI() const { return I; }
 
   void chooseInsnToMutate(RuleMatcher &Rule) {
     for (auto *MutateCandidate : Rule.mutatable_insns()) {
       if (canMutate(Rule, MutateCandidate)) {
         // Take the first one we're offered that we're able to mutate.
         Rule.reserveInsnMatcherForMutation(MutateCandidate);
         Matched = MutateCandidate;
         return;
       }
     }
   }
 
   template <class Kind, class... Args>
   Kind &addRenderer(Args&&... args) {
     OperandRenderers.emplace_back(
         llvm::make_unique<Kind>(InsnID, std::forward<Args>(args)...));
     return *static_cast<Kind *>(OperandRenderers.back().get());
   }
 
   void emitActionOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     if (Matched) {
       assert(canMutate(Rule, Matched) &&
              "Arranged to mutate an insn that isn't mutatable");
 
       unsigned RecycleInsnID = Rule.getInsnVarID(*Matched);
       Table << MatchTable::Opcode("GIR_MutateOpcode")
             << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
             << MatchTable::Comment("RecycleInsnID")
             << MatchTable::IntValue(RecycleInsnID)
             << MatchTable::Comment("Opcode")
             << MatchTable::NamedValue(I->Namespace, I->TheDef->getName())
             << MatchTable::LineBreak;
 
       if (!I->ImplicitDefs.empty() || !I->ImplicitUses.empty()) {
         for (auto Def : I->ImplicitDefs) {
           auto Namespace = Def->getValue("Namespace")
                                ? Def->getValueAsString("Namespace")
                                : "";
           Table << MatchTable::Opcode("GIR_AddImplicitDef")
                 << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
                 << MatchTable::NamedValue(Namespace, Def->getName())
                 << MatchTable::LineBreak;
         }
         for (auto Use : I->ImplicitUses) {
           auto Namespace = Use->getValue("Namespace")
                                ? Use->getValueAsString("Namespace")
                                : "";
           Table << MatchTable::Opcode("GIR_AddImplicitUse")
                 << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
                 << MatchTable::NamedValue(Namespace, Use->getName())
                 << MatchTable::LineBreak;
         }
       }
       return;
     }
 
     // TODO: Simple permutation looks like it could be almost as common as
     //       mutation due to commutative operations.
 
     Table << MatchTable::Opcode("GIR_BuildMI") << MatchTable::Comment("InsnID")
           << MatchTable::IntValue(InsnID) << MatchTable::Comment("Opcode")
           << MatchTable::NamedValue(I->Namespace, I->TheDef->getName())
           << MatchTable::LineBreak;
     for (const auto &Renderer : OperandRenderers)
       Renderer->emitRenderOpcodes(Table, Rule);
 
     if (I->mayLoad || I->mayStore) {
       Table << MatchTable::Opcode("GIR_MergeMemOperands")
             << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
             << MatchTable::Comment("MergeInsnID's");
       // Emit the ID's for all the instructions that are matched by this rule.
       // TODO: Limit this to matched instructions that mayLoad/mayStore or have
       //       some other means of having a memoperand. Also limit this to
       //       emitted instructions that expect to have a memoperand too. For
       //       example, (G_SEXT (G_LOAD x)) that results in separate load and
       //       sign-extend instructions shouldn't put the memoperand on the
       //       sign-extend since it has no effect there.
       std::vector<unsigned> MergeInsnIDs;
       for (const auto &IDMatcherPair : Rule.defined_insn_vars())
         MergeInsnIDs.push_back(IDMatcherPair.second);
       llvm::sort(MergeInsnIDs.begin(), MergeInsnIDs.end());
       for (const auto &MergeInsnID : MergeInsnIDs)
         Table << MatchTable::IntValue(MergeInsnID);
       Table << MatchTable::NamedValue("GIU_MergeMemOperands_EndOfList")
             << MatchTable::LineBreak;
     }
 
     // FIXME: This is a hack but it's sufficient for ISel. We'll need to do
     //        better for combines. Particularly when there are multiple match
     //        roots.
     if (InsnID == 0)
       Table << MatchTable::Opcode("GIR_EraseFromParent")
             << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
             << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to constrain the operands of an output instruction to the
 /// register classes specified by the definition of that instruction.
 class ConstrainOperandsToDefinitionAction : public MatchAction {
   unsigned InsnID;
 
 public:
   ConstrainOperandsToDefinitionAction(unsigned InsnID) : InsnID(InsnID) {}
 
   void emitActionOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIR_ConstrainSelectedInstOperands")
           << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
           << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to constrain the specified operand of an output instruction
 /// to the specified register class.
 class ConstrainOperandToRegClassAction : public MatchAction {
   unsigned InsnID;
   unsigned OpIdx;
   const CodeGenRegisterClass &RC;
 
 public:
   ConstrainOperandToRegClassAction(unsigned InsnID, unsigned OpIdx,
                                    const CodeGenRegisterClass &RC)
       : InsnID(InsnID), OpIdx(OpIdx), RC(RC) {}
 
   void emitActionOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIR_ConstrainOperandRC")
           << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
           << MatchTable::Comment("Op") << MatchTable::IntValue(OpIdx)
           << MatchTable::Comment("RC " + RC.getName())
           << MatchTable::IntValue(RC.EnumValue) << MatchTable::LineBreak;
   }
 };
 
 /// Generates code to create a temporary register which can be used to chain
 /// instructions together.
 class MakeTempRegisterAction : public MatchAction {
 private:
   LLTCodeGen Ty;
   unsigned TempRegID;
 
 public:
   MakeTempRegisterAction(const LLTCodeGen &Ty, unsigned TempRegID)
       : Ty(Ty), TempRegID(TempRegID) {}
 
   void emitActionOpcodes(MatchTable &Table, RuleMatcher &Rule) const override {
     Table << MatchTable::Opcode("GIR_MakeTempReg")
           << MatchTable::Comment("TempRegID") << MatchTable::IntValue(TempRegID)
           << MatchTable::Comment("TypeID")
           << MatchTable::NamedValue(Ty.getCxxEnumValue())
           << MatchTable::LineBreak;
   }
 };
 
 InstructionMatcher &RuleMatcher::addInstructionMatcher(StringRef SymbolicName) {
   Matchers.emplace_back(new InstructionMatcher(*this, SymbolicName));
   MutatableInsns.insert(Matchers.back().get());
   return *Matchers.back();
 }
 
 void RuleMatcher::addRequiredFeature(Record *Feature) {
   RequiredFeatures.push_back(Feature);
 }
 
 const std::vector<Record *> &RuleMatcher::getRequiredFeatures() const {
   return RequiredFeatures;
 }
 
 // Emplaces an action of the specified Kind at the end of the action list.
 //
 // Returns a reference to the newly created action.
 //
 // Like std::vector::emplace_back(), may invalidate all iterators if the new
 // size exceeds the capacity. Otherwise, only invalidates the past-the-end
 // iterator.
 template <class Kind, class... Args>
 Kind &RuleMatcher::addAction(Args &&... args) {
   Actions.emplace_back(llvm::make_unique<Kind>(std::forward<Args>(args)...));
   return *static_cast<Kind *>(Actions.back().get());
 }
 
 // Emplaces an action of the specified Kind before the given insertion point.
 //
 // Returns an iterator pointing at the newly created instruction.
 //
 // Like std::vector::insert(), may invalidate all iterators if the new size
 // exceeds the capacity. Otherwise, only invalidates the iterators from the
 // insertion point onwards.
 template <class Kind, class... Args>
 action_iterator RuleMatcher::insertAction(action_iterator InsertPt,
                                           Args &&... args) {
   return Actions.emplace(InsertPt,
                          llvm::make_unique<Kind>(std::forward<Args>(args)...));
 }
 
 unsigned RuleMatcher::implicitlyDefineInsnVar(InstructionMatcher &Matcher) {
   unsigned NewInsnVarID = NextInsnVarID++;
   InsnVariableIDs[&Matcher] = NewInsnVarID;
   return NewInsnVarID;
 }
 
 unsigned RuleMatcher::getInsnVarID(InstructionMatcher &InsnMatcher) const {
   const auto &I = InsnVariableIDs.find(&InsnMatcher);
   if (I != InsnVariableIDs.end())
     return I->second;
   llvm_unreachable("Matched Insn was not captured in a local variable");
 }
 
 void RuleMatcher::defineOperand(StringRef SymbolicName, OperandMatcher &OM) {
   if (DefinedOperands.find(SymbolicName) == DefinedOperands.end()) {
     DefinedOperands[SymbolicName] = &OM;
     return;
   }
 
   // If the operand is already defined, then we must ensure both references in
   // the matcher have the exact same node.
   OM.addPredicate<SameOperandMatcher>(OM.getSymbolicName());
 }
 
 InstructionMatcher &
 RuleMatcher::getInstructionMatcher(StringRef SymbolicName) const {
   for (const auto &I : InsnVariableIDs)
     if (I.first->getSymbolicName() == SymbolicName)
       return *I.first;
   llvm_unreachable(
       ("Failed to lookup instruction " + SymbolicName).str().c_str());
 }
 
 const OperandMatcher &
 RuleMatcher::getOperandMatcher(StringRef Name) const {
   const auto &I = DefinedOperands.find(Name);
 
   if (I == DefinedOperands.end())
     PrintFatalError(SrcLoc, "Operand " + Name + " was not declared in matcher");
 
   return *I->second;
 }
 
 void RuleMatcher::emit(MatchTable &Table) {
   if (Matchers.empty())
     llvm_unreachable("Unexpected empty matcher!");
 
   // The representation supports rules that require multiple roots such as:
   //    %ptr(p0) = ...
   //    %elt0(s32) = G_LOAD %ptr
   //    %1(p0) = G_ADD %ptr, 4
   //    %elt1(s32) = G_LOAD p0 %1
   // which could be usefully folded into:
   //    %ptr(p0) = ...
   //    %elt0(s32), %elt1(s32) = TGT_LOAD_PAIR %ptr
   // on some targets but we don't need to make use of that yet.
   assert(Matchers.size() == 1 && "Cannot handle multi-root matchers yet");
 
   unsigned LabelID = Table.allocateLabelID();
   Table << MatchTable::Opcode("GIM_Try", +1)
         << MatchTable::Comment("On fail goto")
         << MatchTable::JumpTarget(LabelID)
         << MatchTable::Comment(("Rule ID " + Twine(RuleID) + " //").str())
         << MatchTable::LineBreak;
 
   if (!RequiredFeatures.empty()) {
     Table << MatchTable::Opcode("GIM_CheckFeatures")
           << MatchTable::NamedValue(getNameForFeatureBitset(RequiredFeatures))
           << MatchTable::LineBreak;
   }
 
   Matchers.front()->emitPredicateOpcodes(Table, *this);
 
   // We must also check if it's safe to fold the matched instructions.
   if (InsnVariableIDs.size() >= 2) {
     // Invert the map to create stable ordering (by var names)
     SmallVector<unsigned, 2> InsnIDs;
     for (const auto &Pair : InsnVariableIDs) {
       // Skip the root node since it isn't moving anywhere. Everything else is
       // sinking to meet it.
       if (Pair.first == Matchers.front().get())
         continue;
 
       InsnIDs.push_back(Pair.second);
     }
     llvm::sort(InsnIDs.begin(), InsnIDs.end());
 
     for (const auto &InsnID : InsnIDs) {
       // Reject the difficult cases until we have a more accurate check.
       Table << MatchTable::Opcode("GIM_CheckIsSafeToFold")
             << MatchTable::Comment("InsnID") << MatchTable::IntValue(InsnID)
             << MatchTable::LineBreak;
 
       // FIXME: Emit checks to determine it's _actually_ safe to fold and/or
       //        account for unsafe cases.
       //
       //        Example:
       //          MI1--> %0 = ...
       //                 %1 = ... %0
       //          MI0--> %2 = ... %0
       //          It's not safe to erase MI1. We currently handle this by not
       //          erasing %0 (even when it's dead).
       //
       //        Example:
       //          MI1--> %0 = load volatile @a
       //                 %1 = load volatile @a
       //          MI0--> %2 = ... %0
       //          It's not safe to sink %0's def past %1. We currently handle
       //          this by rejecting all loads.
       //
       //        Example:
       //          MI1--> %0 = load @a
       //                 %1 = store @a
       //          MI0--> %2 = ... %0
       //          It's not safe to sink %0's def past %1. We currently handle
       //          this by rejecting all loads.
       //
       //        Example:
       //                   G_CONDBR %cond, @BB1
       //                 BB0:
       //          MI1-->   %0 = load @a
       //                   G_BR @BB1
       //                 BB1:
       //          MI0-->   %2 = ... %0
       //          It's not always safe to sink %0 across control flow. In this
       //          case it may introduce a memory fault. We currentl handle this
       //          by rejecting all loads.
     }
   }
 
   for (const auto &PM : EpilogueMatchers)
     PM->emitPredicateOpcodes(Table, *this);
 
   for (const auto &MA : Actions)
     MA->emitActionOpcodes(Table, *this);
 
   if (Table.isWithCoverage())
     Table << MatchTable::Opcode("GIR_Coverage") << MatchTable::IntValue(RuleID)
           << MatchTable::LineBreak;
   else
     Table << MatchTable::Comment(("GIR_Coverage, " + Twine(RuleID) + ",").str())
           << MatchTable::LineBreak;
 
   Table << MatchTable::Opcode("GIR_Done", -1) << MatchTable::LineBreak
         << MatchTable::Label(LabelID);
   ++NumPatternEmitted;
 }
 
 bool RuleMatcher::isHigherPriorityThan(const RuleMatcher &B) const {
   // Rules involving more match roots have higher priority.
   if (Matchers.size() > B.Matchers.size())
     return true;
   if (Matchers.size() < B.Matchers.size())
     return false;
 
   for (const auto &Matcher : zip(Matchers, B.Matchers)) {
     if (std::get<0>(Matcher)->isHigherPriorityThan(*std::get<1>(Matcher)))
       return true;
     if (std::get<1>(Matcher)->isHigherPriorityThan(*std::get<0>(Matcher)))
       return false;
   }
 
   return false;
 }
 
 unsigned RuleMatcher::countRendererFns() const {
   return std::accumulate(
       Matchers.begin(), Matchers.end(), 0,
       [](unsigned A, const std::unique_ptr<InstructionMatcher> &Matcher) {
         return A + Matcher->countRendererFns();
       });
 }
 
 bool OperandPredicateMatcher::isHigherPriorityThan(
     const OperandPredicateMatcher &B) const {
   // Generally speaking, an instruction is more important than an Int or a
   // LiteralInt because it can cover more nodes but theres an exception to
   // this. G_CONSTANT's are less important than either of those two because they
   // are more permissive.
 
   const InstructionOperandMatcher *AOM =
       dyn_cast<InstructionOperandMatcher>(this);
   const InstructionOperandMatcher *BOM =
       dyn_cast<InstructionOperandMatcher>(&B);
   bool AIsConstantInsn = AOM && AOM->getInsnMatcher().isConstantInstruction();
   bool BIsConstantInsn = BOM && BOM->getInsnMatcher().isConstantInstruction();
 
   if (AOM && BOM) {
     // The relative priorities between a G_CONSTANT and any other instruction
     // don't actually matter but this code is needed to ensure a strict weak
     // ordering. This is particularly important on Windows where the rules will
     // be incorrectly sorted without it.
     if (AIsConstantInsn != BIsConstantInsn)
       return AIsConstantInsn < BIsConstantInsn;
     return false;
   }
 
   if (AOM && AIsConstantInsn && (B.Kind == OPM_Int || B.Kind == OPM_LiteralInt))
     return false;
   if (BOM && BIsConstantInsn && (Kind == OPM_Int || Kind == OPM_LiteralInt))
     return true;
 
   return Kind < B.Kind;
 }
 
 void SameOperandMatcher::emitPredicateOpcodes(MatchTable &Table,
                                               RuleMatcher &Rule) const {
   const OperandMatcher &OtherOM = Rule.getOperandMatcher(MatchingName);
   unsigned OtherInsnVarID = Rule.getInsnVarID(OtherOM.getInstructionMatcher());
   assert(OtherInsnVarID == OtherOM.getInstructionMatcher().getInsnVarID());
 
   Table << MatchTable::Opcode("GIM_CheckIsSameOperand")
         << MatchTable::Comment("MI") << MatchTable::IntValue(InsnVarID)
         << MatchTable::Comment("OpIdx") << MatchTable::IntValue(OpIdx)
         << MatchTable::Comment("OtherMI")
         << MatchTable::IntValue(OtherInsnVarID)
         << MatchTable::Comment("OtherOpIdx")
         << MatchTable::IntValue(OtherOM.getOpIdx())
         << MatchTable::LineBreak;
 }
 
 //===- GlobalISelEmitter class --------------------------------------------===//
 
 class GlobalISelEmitter {
 public:
   explicit GlobalISelEmitter(RecordKeeper &RK);
   void run(raw_ostream &OS);
 
 private:
   const RecordKeeper &RK;
   const CodeGenDAGPatterns CGP;
   const CodeGenTarget &Target;
   CodeGenRegBank CGRegs;
 
   /// Keep track of the equivalence between SDNodes and Instruction by mapping
   /// SDNodes to the GINodeEquiv mapping. We need to map to the GINodeEquiv to
   /// check for attributes on the relation such as CheckMMOIsNonAtomic.
   /// This is defined using 'GINodeEquiv' in the target description.
   DenseMap<Record *, Record *> NodeEquivs;
 
   /// Keep track of the equivalence between ComplexPattern's and
   /// GIComplexOperandMatcher. Map entries are specified by subclassing
   /// GIComplexPatternEquiv.
   DenseMap<const Record *, const Record *> ComplexPatternEquivs;
 
   /// Keep track of the equivalence between SDNodeXForm's and
   /// GICustomOperandRenderer. Map entries are specified by subclassing
   /// GISDNodeXFormEquiv.
   DenseMap<const Record *, const Record *> SDNodeXFormEquivs;
 
   /// Keep track of Scores of PatternsToMatch similar to how the DAG does.
   /// This adds compatibility for RuleMatchers to use this for ordering rules.
   DenseMap<uint64_t, int> RuleMatcherScores;
 
   // Map of predicates to their subtarget features.
   SubtargetFeatureInfoMap SubtargetFeatures;
 
   // Rule coverage information.
   Optional<CodeGenCoverage> RuleCoverage;
 
   void gatherOpcodeValues();
   void gatherTypeIDValues();
   void gatherNodeEquivs();
   Record *findNodeEquiv(Record *N) const;
   const CodeGenInstruction *getEquivNode(Record &Equiv,
                                          const TreePatternNode *N) const;
 
   Error importRulePredicates(RuleMatcher &M, ArrayRef<Predicate> Predicates);
   Expected<InstructionMatcher &> createAndImportSelDAGMatcher(
       RuleMatcher &Rule, InstructionMatcher &InsnMatcher,
       const TreePatternNode *Src, unsigned &TempOpIdx) const;
   Error importComplexPatternOperandMatcher(OperandMatcher &OM, Record *R,
                                            unsigned &TempOpIdx) const;
   Error importChildMatcher(RuleMatcher &Rule, InstructionMatcher &InsnMatcher,
                            const TreePatternNode *SrcChild,
                            bool OperandIsAPointer, unsigned OpIdx,
                            unsigned &TempOpIdx) const;
 
   Expected<BuildMIAction &>
   createAndImportInstructionRenderer(RuleMatcher &M,
                                      const TreePatternNode *Dst);
   Expected<action_iterator> createAndImportSubInstructionRenderer(
       action_iterator InsertPt, RuleMatcher &M, const TreePatternNode *Dst,
       unsigned TempReg);
   Expected<action_iterator>
   createInstructionRenderer(action_iterator InsertPt, RuleMatcher &M,
                             const TreePatternNode *Dst);
   void importExplicitDefRenderers(BuildMIAction &DstMIBuilder);
   Expected<action_iterator>
   importExplicitUseRenderers(action_iterator InsertPt, RuleMatcher &M,
                              BuildMIAction &DstMIBuilder,
                              const llvm::TreePatternNode *Dst);
   Expected<action_iterator>
   importExplicitUseRenderer(action_iterator InsertPt, RuleMatcher &Rule,
                             BuildMIAction &DstMIBuilder,
                             TreePatternNode *DstChild);
   Error importDefaultOperandRenderers(BuildMIAction &DstMIBuilder,
                                       DagInit *DefaultOps) const;
   Error
   importImplicitDefRenderers(BuildMIAction &DstMIBuilder,
                              const std::vector<Record *> &ImplicitDefs) const;
 
   void emitImmPredicates(raw_ostream &OS, StringRef TypeIdentifier,
                          StringRef Type,
                          std::function<bool(const Record *R)> Filter);
 
   /// Analyze pattern \p P, returning a matcher for it if possible.
   /// Otherwise, return an Error explaining why we don't support it.
   Expected<RuleMatcher> runOnPattern(const PatternToMatch &P);
 
   void declareSubtargetFeature(Record *Predicate);
 
   MatchTable buildMatchTable(MutableArrayRef<RuleMatcher> Rules, bool Optimize,
                              bool WithCoverage);
 
 public:
   /// Takes a sequence of \p Rules and group them based on the predicates
   /// they share. \p MatcherStorage is used as a memory container
   /// for the group that are created as part of this process.
   ///
   /// What this optimization does looks like if GroupT = GroupMatcher:
   /// Output without optimization:
   /// \verbatim
   /// # R1
   ///  # predicate A
   ///  # predicate B
   ///  ...
   /// # R2
   ///  # predicate A // <-- effectively this is going to be checked twice.
   ///                //     Once in R1 and once in R2.
   ///  # predicate C
   /// \endverbatim
   /// Output with optimization:
   /// \verbatim
   /// # Group1_2
   ///  # predicate A // <-- Check is now shared.
   ///  # R1
   ///   # predicate B
   ///  # R2
   ///   # predicate C
   /// \endverbatim
   template <class GroupT>
   static std::vector<Matcher *> optimizeRules(
       ArrayRef<Matcher *> Rules,
       std::vector<std::unique_ptr<Matcher>> &MatcherStorage);
 };
 
 void GlobalISelEmitter::gatherOpcodeValues() {
   InstructionOpcodeMatcher::initOpcodeValuesMap(Target);
 }
 
 void GlobalISelEmitter::gatherTypeIDValues() {
   LLTOperandMatcher::initTypeIDValuesMap();
 }
 
 void GlobalISelEmitter::gatherNodeEquivs() {
   assert(NodeEquivs.empty());
   for (Record *Equiv : RK.getAllDerivedDefinitions("GINodeEquiv"))
     NodeEquivs[Equiv->getValueAsDef("Node")] = Equiv;
 
   assert(ComplexPatternEquivs.empty());
   for (Record *Equiv : RK.getAllDerivedDefinitions("GIComplexPatternEquiv")) {
     Record *SelDAGEquiv = Equiv->getValueAsDef("SelDAGEquivalent");
     if (!SelDAGEquiv)
       continue;
     ComplexPatternEquivs[SelDAGEquiv] = Equiv;
  }
 
  assert(SDNodeXFormEquivs.empty());
  for (Record *Equiv : RK.getAllDerivedDefinitions("GISDNodeXFormEquiv")) {
    Record *SelDAGEquiv = Equiv->getValueAsDef("SelDAGEquivalent");
    if (!SelDAGEquiv)
      continue;
    SDNodeXFormEquivs[SelDAGEquiv] = Equiv;
  }
 }
 
 Record *GlobalISelEmitter::findNodeEquiv(Record *N) const {
   return NodeEquivs.lookup(N);
 }
 
 const CodeGenInstruction *
 GlobalISelEmitter::getEquivNode(Record &Equiv, const TreePatternNode *N) const {
   for (const auto &Predicate : N->getPredicateFns()) {
     if (!Equiv.isValueUnset("IfSignExtend") && Predicate.isLoad() &&
         Predicate.isSignExtLoad())
       return &Target.getInstruction(Equiv.getValueAsDef("IfSignExtend"));
     if (!Equiv.isValueUnset("IfZeroExtend") && Predicate.isLoad() &&
         Predicate.isZeroExtLoad())
       return &Target.getInstruction(Equiv.getValueAsDef("IfZeroExtend"));
   }
   return &Target.getInstruction(Equiv.getValueAsDef("I"));
 }
 
 GlobalISelEmitter::GlobalISelEmitter(RecordKeeper &RK)
     : RK(RK), CGP(RK), Target(CGP.getTargetInfo()),
       CGRegs(RK, Target.getHwModes()) {}
 
 //===- Emitter ------------------------------------------------------------===//
 
 Error
 GlobalISelEmitter::importRulePredicates(RuleMatcher &M,
                                         ArrayRef<Predicate> Predicates) {
   for (const Predicate &P : Predicates) {
     if (!P.Def)
       continue;
     declareSubtargetFeature(P.Def);
     M.addRequiredFeature(P.Def);
   }
 
   return Error::success();
 }
 
 Expected<InstructionMatcher &> GlobalISelEmitter::createAndImportSelDAGMatcher(
     RuleMatcher &Rule, InstructionMatcher &InsnMatcher,
     const TreePatternNode *Src, unsigned &TempOpIdx) const {
   Record *SrcGIEquivOrNull = nullptr;
   const CodeGenInstruction *SrcGIOrNull = nullptr;
 
   // Start with the defined operands (i.e., the results of the root operator).
   if (Src->getExtTypes().size() > 1)
     return failedImport("Src pattern has multiple results");
 
   if (Src->isLeaf()) {
     Init *SrcInit = Src->getLeafValue();
     if (isa<IntInit>(SrcInit)) {
       InsnMatcher.addPredicate<InstructionOpcodeMatcher>(
           &Target.getInstruction(RK.getDef("G_CONSTANT")));
     } else
       return failedImport(
           "Unable to deduce gMIR opcode to handle Src (which is a leaf)");
   } else {
     SrcGIEquivOrNull = findNodeEquiv(Src->getOperator());
     if (!SrcGIEquivOrNull)
       return failedImport("Pattern operator lacks an equivalent Instruction" +
                           explainOperator(Src->getOperator()));
     SrcGIOrNull = getEquivNode(*SrcGIEquivOrNull, Src);
 
     // The operators look good: match the opcode
     InsnMatcher.addPredicate<InstructionOpcodeMatcher>(SrcGIOrNull);
   }
 
   unsigned OpIdx = 0;
   for (const TypeSetByHwMode &VTy : Src->getExtTypes()) {
     // Results don't have a name unless they are the root node. The caller will
     // set the name if appropriate.
     OperandMatcher &OM = InsnMatcher.addOperand(OpIdx++, "", TempOpIdx);
     if (auto Error = OM.addTypeCheckPredicate(VTy, false /* OperandIsAPointer */))
       return failedImport(toString(std::move(Error)) +
                           " for result of Src pattern operator");
   }
 
   for (const auto &Predicate : Src->getPredicateFns()) {
     if (Predicate.isAlwaysTrue())
       continue;
 
     if (Predicate.isImmediatePattern()) {
       InsnMatcher.addPredicate<InstructionImmPredicateMatcher>(Predicate);
       continue;
     }
 
     // G_LOAD is used for both non-extending and any-extending loads. 
     if (Predicate.isLoad() && Predicate.isNonExtLoad()) {
       InsnMatcher.addPredicate<MemoryVsLLTSizePredicateMatcher>(
           0, MemoryVsLLTSizePredicateMatcher::EqualTo, 0);
       continue;
     }
     if (Predicate.isLoad() && Predicate.isAnyExtLoad()) {
       InsnMatcher.addPredicate<MemoryVsLLTSizePredicateMatcher>(
           0, MemoryVsLLTSizePredicateMatcher::LessThan, 0);
       continue;
     }
 
     // No check required. We already did it by swapping the opcode.
     if (!SrcGIEquivOrNull->isValueUnset("IfSignExtend") &&
         Predicate.isSignExtLoad())
       continue;
 
     // No check required. We already did it by swapping the opcode.
     if (!SrcGIEquivOrNull->isValueUnset("IfZeroExtend") &&
         Predicate.isZeroExtLoad())
       continue;
 
     // No check required. G_STORE by itself is a non-extending store.
     if (Predicate.isNonTruncStore())
       continue;
 
     if (Predicate.isLoad() || Predicate.isStore() || Predicate.isAtomic()) {
       if (Predicate.getMemoryVT() != nullptr) {
         Optional<LLTCodeGen> MemTyOrNone =
             MVTToLLT(getValueType(Predicate.getMemoryVT()));
 
         if (!MemTyOrNone)
           return failedImport("MemVT could not be converted to LLT");
 
         // MMO's work in bytes so we must take care of unusual types like i1
         // don't round down.
         unsigned MemSizeInBits =
             llvm::alignTo(MemTyOrNone->get().getSizeInBits(), 8);
 
         InsnMatcher.addPredicate<MemorySizePredicateMatcher>(
             0, MemSizeInBits / 8);
         continue;
       }
     }
 
     if (Predicate.isLoad() || Predicate.isStore()) {
       // No check required. A G_LOAD/G_STORE is an unindexed load.
       if (Predicate.isUnindexed())
         continue;
     }
 
     if (Predicate.isAtomic()) {
       if (Predicate.isAtomicOrderingMonotonic()) {
         InsnMatcher.addPredicate<AtomicOrderingMMOPredicateMatcher>(
             "Monotonic");
         continue;
       }
       if (Predicate.isAtomicOrderingAcquire()) {
         InsnMatcher.addPredicate<AtomicOrderingMMOPredicateMatcher>("Acquire");
         continue;
       }
       if (Predicate.isAtomicOrderingRelease()) {
         InsnMatcher.addPredicate<AtomicOrderingMMOPredicateMatcher>("Release");
         continue;
       }
       if (Predicate.isAtomicOrderingAcquireRelease()) {
         InsnMatcher.addPredicate<AtomicOrderingMMOPredicateMatcher>(
             "AcquireRelease");
         continue;
       }
       if (Predicate.isAtomicOrderingSequentiallyConsistent()) {
         InsnMatcher.addPredicate<AtomicOrderingMMOPredicateMatcher>(
             "SequentiallyConsistent");
         continue;
       }
 
       if (Predicate.isAtomicOrderingAcquireOrStronger()) {
         InsnMatcher.addPredicate<AtomicOrderingMMOPredicateMatcher>(
             "Acquire", AtomicOrderingMMOPredicateMatcher::AO_OrStronger);
         continue;
       }
       if (Predicate.isAtomicOrderingWeakerThanAcquire()) {
         InsnMatcher.addPredicate<AtomicOrderingMMOPredicateMatcher>(
             "Acquire", AtomicOrderingMMOPredicateMatcher::AO_WeakerThan);
         continue;
       }
 
       if (Predicate.isAtomicOrderingReleaseOrStronger()) {
         InsnMatcher.addPredicate<AtomicOrderingMMOPredicateMatcher>(
             "Release", AtomicOrderingMMOPredicateMatcher::AO_OrStronger);
         continue;
       }
       if (Predicate.isAtomicOrderingWeakerThanRelease()) {
         InsnMatcher.addPredicate<AtomicOrderingMMOPredicateMatcher>(
             "Release", AtomicOrderingMMOPredicateMatcher::AO_WeakerThan);
         continue;
       }
     }
 
     return failedImport("Src pattern child has predicate (" +
                         explainPredicates(Src) + ")");
   }
   if (SrcGIEquivOrNull && SrcGIEquivOrNull->getValueAsBit("CheckMMOIsNonAtomic"))
     InsnMatcher.addPredicate<AtomicOrderingMMOPredicateMatcher>("NotAtomic");
 
   if (Src->isLeaf()) {
     Init *SrcInit = Src->getLeafValue();
     if (IntInit *SrcIntInit = dyn_cast<IntInit>(SrcInit)) {
       OperandMatcher &OM =
           InsnMatcher.addOperand(OpIdx++, Src->getName(), TempOpIdx);
       OM.addPredicate<LiteralIntOperandMatcher>(SrcIntInit->getValue());
     } else
       return failedImport(
           "Unable to deduce gMIR opcode to handle Src (which is a leaf)");
   } else {
     assert(SrcGIOrNull &&
            "Expected to have already found an equivalent Instruction");
     if (SrcGIOrNull->TheDef->getName() == "G_CONSTANT" ||
         SrcGIOrNull->TheDef->getName() == "G_FCONSTANT") {
       // imm/fpimm still have operands but we don't need to do anything with it
       // here since we don't support ImmLeaf predicates yet. However, we still
       // need to note the hidden operand to get GIM_CheckNumOperands correct.
       InsnMatcher.addOperand(OpIdx++, "", TempOpIdx);
       return InsnMatcher;
     }
 
     // Match the used operands (i.e. the children of the operator).
     for (unsigned i = 0, e = Src->getNumChildren(); i != e; ++i) {
       TreePatternNode *SrcChild = Src->getChild(i);
 
       // SelectionDAG allows pointers to be represented with iN since it doesn't
       // distinguish between pointers and integers but they are different types in GlobalISel.
       // Coerce integers to pointers to address space 0 if the context indicates a pointer.
       bool OperandIsAPointer = SrcGIOrNull->isOperandAPointer(i);
 
       // For G_INTRINSIC/G_INTRINSIC_W_SIDE_EFFECTS, the operand immediately
       // following the defs is an intrinsic ID.
       if ((SrcGIOrNull->TheDef->getName() == "G_INTRINSIC" ||
            SrcGIOrNull->TheDef->getName() == "G_INTRINSIC_W_SIDE_EFFECTS") &&
           i == 0) {
         if (const CodeGenIntrinsic *II = Src->getIntrinsicInfo(CGP)) {
           OperandMatcher &OM =
               InsnMatcher.addOperand(OpIdx++, SrcChild->getName(), TempOpIdx);
           OM.addPredicate<IntrinsicIDOperandMatcher>(II);
           continue;
         }
 
         return failedImport("Expected IntInit containing instrinsic ID)");
       }
 
       if (auto Error =
               importChildMatcher(Rule, InsnMatcher, SrcChild, OperandIsAPointer,
                                  OpIdx++, TempOpIdx))
         return std::move(Error);
     }
   }
 
   return InsnMatcher;
 }
 
 Error GlobalISelEmitter::importComplexPatternOperandMatcher(
     OperandMatcher &OM, Record *R, unsigned &TempOpIdx) const {
   const auto &ComplexPattern = ComplexPatternEquivs.find(R);
   if (ComplexPattern == ComplexPatternEquivs.end())
     return failedImport("SelectionDAG ComplexPattern (" + R->getName() +
                         ") not mapped to GlobalISel");
 
   OM.addPredicate<ComplexPatternOperandMatcher>(OM, *ComplexPattern->second);
   TempOpIdx++;
   return Error::success();
 }
 
 Error GlobalISelEmitter::importChildMatcher(RuleMatcher &Rule,
                                             InstructionMatcher &InsnMatcher,
                                             const TreePatternNode *SrcChild,
                                             bool OperandIsAPointer,
                                             unsigned OpIdx,
                                             unsigned &TempOpIdx) const {
   OperandMatcher &OM =
       InsnMatcher.addOperand(OpIdx, SrcChild->getName(), TempOpIdx);
   if (OM.isSameAsAnotherOperand())
     return Error::success();
 
   ArrayRef<TypeSetByHwMode> ChildTypes = SrcChild->getExtTypes();
   if (ChildTypes.size() != 1)
     return failedImport("Src pattern child has multiple results");
 
   // Check MBB's before the type check since they are not a known type.
   if (!SrcChild->isLeaf()) {
     if (SrcChild->getOperator()->isSubClassOf("SDNode")) {
       auto &ChildSDNI = CGP.getSDNodeInfo(SrcChild->getOperator());
       if (ChildSDNI.getSDClassName() == "BasicBlockSDNode") {
         OM.addPredicate<MBBOperandMatcher>();
         return Error::success();
       }
     }
   }
 
   if (auto Error =
           OM.addTypeCheckPredicate(ChildTypes.front(), OperandIsAPointer))
     return failedImport(toString(std::move(Error)) + " for Src operand (" +
                         to_string(*SrcChild) + ")");
 
   // Check for nested instructions.
   if (!SrcChild->isLeaf()) {
     if (SrcChild->getOperator()->isSubClassOf("ComplexPattern")) {
       // When a ComplexPattern is used as an operator, it should do the same
       // thing as when used as a leaf. However, the children of the operator
       // name the sub-operands that make up the complex operand and we must
       // prepare to reference them in the renderer too.
       unsigned RendererID = TempOpIdx;
       if (auto Error = importComplexPatternOperandMatcher(
               OM, SrcChild->getOperator(), TempOpIdx))
         return Error;
 
       for (unsigned i = 0, e = SrcChild->getNumChildren(); i != e; ++i) {
         auto *SubOperand = SrcChild->getChild(i);
         if (!SubOperand->getName().empty())
           Rule.defineComplexSubOperand(SubOperand->getName(),
                                        SrcChild->getOperator(), RendererID, i);
       }
 
       return Error::success();
     }
 
     auto MaybeInsnOperand = OM.addPredicate<InstructionOperandMatcher>(
         InsnMatcher.getRuleMatcher(), SrcChild->getName());
     if (!MaybeInsnOperand.hasValue()) {
       // This isn't strictly true. If the user were to provide exactly the same
       // matchers as the original operand then we could allow it. However, it's
       // simpler to not permit the redundant specification.
       return failedImport("Nested instruction cannot be the same as another operand");
     }
 
     // Map the node to a gMIR instruction.
     InstructionOperandMatcher &InsnOperand = **MaybeInsnOperand;
     auto InsnMatcherOrError = createAndImportSelDAGMatcher(
         Rule, InsnOperand.getInsnMatcher(), SrcChild, TempOpIdx);
     if (auto Error = InsnMatcherOrError.takeError())
       return Error;
 
     return Error::success();
   }
 
   if (SrcChild->hasAnyPredicate())
     return failedImport("Src pattern child has unsupported predicate");
 
   // Check for constant immediates.
   if (auto *ChildInt = dyn_cast<IntInit>(SrcChild->getLeafValue())) {
     OM.addPredicate<ConstantIntOperandMatcher>(ChildInt->getValue());
     return Error::success();
   }
 
   // Check for def's like register classes or ComplexPattern's.
   if (auto *ChildDefInit = dyn_cast<DefInit>(SrcChild->getLeafValue())) {
     auto *ChildRec = ChildDefInit->getDef();
 
     // Check for register classes.
     if (ChildRec->isSubClassOf("RegisterClass") ||
         ChildRec->isSubClassOf("RegisterOperand")) {
       OM.addPredicate<RegisterBankOperandMatcher>(
           Target.getRegisterClass(getInitValueAsRegClass(ChildDefInit)));
       return Error::success();
     }
 
     // Check for ValueType.
     if (ChildRec->isSubClassOf("ValueType")) {
       // We already added a type check as standard practice so this doesn't need
       // to do anything.
       return Error::success();
     }
 
     // Check for ComplexPattern's.
     if (ChildRec->isSubClassOf("ComplexPattern"))
       return importComplexPatternOperandMatcher(OM, ChildRec, TempOpIdx);
 
     if (ChildRec->isSubClassOf("ImmLeaf")) {
       return failedImport(
           "Src pattern child def is an unsupported tablegen class (ImmLeaf)");
     }
 
     return failedImport(
         "Src pattern child def is an unsupported tablegen class");
   }
 
   return failedImport("Src pattern child is an unsupported kind");
 }
 
 Expected<action_iterator> GlobalISelEmitter::importExplicitUseRenderer(
     action_iterator InsertPt, RuleMatcher &Rule, BuildMIAction &DstMIBuilder,
     TreePatternNode *DstChild) {
 
   const auto &SubOperand = Rule.getComplexSubOperand(DstChild->getName());
   if (SubOperand.hasValue()) {
     DstMIBuilder.addRenderer<RenderComplexPatternOperand>(
         *std::get<0>(*SubOperand), DstChild->getName(),
         std::get<1>(*SubOperand), std::get<2>(*SubOperand));
     return InsertPt;
   }
 
   if (!DstChild->isLeaf()) {
 
     if (DstChild->getOperator()->isSubClassOf("SDNodeXForm")) {
       auto Child = DstChild->getChild(0);
       auto I = SDNodeXFormEquivs.find(DstChild->getOperator());
       if (I != SDNodeXFormEquivs.end()) {
         DstMIBuilder.addRenderer<CustomRenderer>(*I->second, Child->getName());
         return InsertPt;
       }
       return failedImport("SDNodeXForm " + Child->getName() +
                           " has no custom renderer");
     }
 
     // We accept 'bb' here. It's an operator because BasicBlockSDNode isn't
     // inline, but in MI it's just another operand.
     if (DstChild->getOperator()->isSubClassOf("SDNode")) {
       auto &ChildSDNI = CGP.getSDNodeInfo(DstChild->getOperator());
       if (ChildSDNI.getSDClassName() == "BasicBlockSDNode") {
         DstMIBuilder.addRenderer<CopyRenderer>(DstChild->getName());
         return InsertPt;
       }
     }
 
     // Similarly, imm is an operator in TreePatternNode's view but must be
     // rendered as operands.
     // FIXME: The target should be able to choose sign-extended when appropriate
     //        (e.g. on Mips).
     if (DstChild->getOperator()->getName() == "imm") {
       DstMIBuilder.addRenderer<CopyConstantAsImmRenderer>(DstChild->getName());
       return InsertPt;
     } else if (DstChild->getOperator()->getName() == "fpimm") {
       DstMIBuilder.addRenderer<CopyFConstantAsFPImmRenderer>(
           DstChild->getName());
       return InsertPt;
     }
 
     if (DstChild->getOperator()->isSubClassOf("Instruction")) {
       ArrayRef<TypeSetByHwMode> ChildTypes = DstChild->getExtTypes();
       if (ChildTypes.size() != 1)
         return failedImport("Dst pattern child has multiple results");
 
       Optional<LLTCodeGen> OpTyOrNone = None;
       if (ChildTypes.front().isMachineValueType())
         OpTyOrNone =
             MVTToLLT(ChildTypes.front().getMachineValueType().SimpleTy);
       if (!OpTyOrNone)
         return failedImport("Dst operand has an unsupported type");
 
       unsigned TempRegID = Rule.allocateTempRegID();
       InsertPt = Rule.insertAction<MakeTempRegisterAction>(
           InsertPt, OpTyOrNone.getValue(), TempRegID);
       DstMIBuilder.addRenderer<TempRegRenderer>(TempRegID);
 
       auto InsertPtOrError = createAndImportSubInstructionRenderer(
           ++InsertPt, Rule, DstChild, TempRegID);
       if (auto Error = InsertPtOrError.takeError())
         return std::move(Error);
       return InsertPtOrError.get();
     }
 
     return failedImport("Dst pattern child isn't a leaf node or an MBB" + llvm::to_string(*DstChild));
   }
 
   // It could be a specific immediate in which case we should just check for
   // that immediate.
   if (const IntInit *ChildIntInit =
           dyn_cast<IntInit>(DstChild->getLeafValue())) {
     DstMIBuilder.addRenderer<ImmRenderer>(ChildIntInit->getValue());
     return InsertPt;
   }
 
   // Otherwise, we're looking for a bog-standard RegisterClass operand.
   if (auto *ChildDefInit = dyn_cast<DefInit>(DstChild->getLeafValue())) {
     auto *ChildRec = ChildDefInit->getDef();
 
     ArrayRef<TypeSetByHwMode> ChildTypes = DstChild->getExtTypes();
     if (ChildTypes.size() != 1)
       return failedImport("Dst pattern child has multiple results");
 
     Optional<LLTCodeGen> OpTyOrNone = None;
     if (ChildTypes.front().isMachineValueType())
       OpTyOrNone = MVTToLLT(ChildTypes.front().getMachineValueType().SimpleTy);
     if (!OpTyOrNone)
       return failedImport("Dst operand has an unsupported type");
 
     if (ChildRec->isSubClassOf("Register")) {
       DstMIBuilder.addRenderer<AddRegisterRenderer>(ChildRec);
       return InsertPt;
     }
 
     if (ChildRec->isSubClassOf("RegisterClass") ||
         ChildRec->isSubClassOf("RegisterOperand") ||
         ChildRec->isSubClassOf("ValueType")) {
       if (ChildRec->isSubClassOf("RegisterOperand") &&
           !ChildRec->isValueUnset("GIZeroRegister")) {
         DstMIBuilder.addRenderer<CopyOrAddZeroRegRenderer>(
             DstChild->getName(), ChildRec->getValueAsDef("GIZeroRegister"));
         return InsertPt;
       }
 
       DstMIBuilder.addRenderer<CopyRenderer>(DstChild->getName());
       return InsertPt;
     }
 
     if (ChildRec->isSubClassOf("ComplexPattern")) {
       const auto &ComplexPattern = ComplexPatternEquivs.find(ChildRec);
       if (ComplexPattern == ComplexPatternEquivs.end())
         return failedImport(
             "SelectionDAG ComplexPattern not mapped to GlobalISel");
 
       const OperandMatcher &OM = Rule.getOperandMatcher(DstChild->getName());
       DstMIBuilder.addRenderer<RenderComplexPatternOperand>(
           *ComplexPattern->second, DstChild->getName(),
           OM.getAllocatedTemporariesBaseID());
       return InsertPt;
     }
 
     return failedImport(
         "Dst pattern child def is an unsupported tablegen class");
   }
 
   return failedImport("Dst pattern child is an unsupported kind");
 }
 
 Expected<BuildMIAction &> GlobalISelEmitter::createAndImportInstructionRenderer(
     RuleMatcher &M, const TreePatternNode *Dst) {
   auto InsertPtOrError = createInstructionRenderer(M.actions_end(), M, Dst);
   if (auto Error = InsertPtOrError.takeError())
     return std::move(Error);
 
   action_iterator InsertPt = InsertPtOrError.get();
   BuildMIAction &DstMIBuilder = *static_cast<BuildMIAction *>(InsertPt->get());
 
   importExplicitDefRenderers(DstMIBuilder);
 
   if (auto Error = importExplicitUseRenderers(InsertPt, M, DstMIBuilder, Dst)
                        .takeError())
     return std::move(Error);
 
   return DstMIBuilder;
 }
 
 Expected<action_iterator>
 GlobalISelEmitter::createAndImportSubInstructionRenderer(
     const action_iterator InsertPt, RuleMatcher &M, const TreePatternNode *Dst,
     unsigned TempRegID) {
   auto InsertPtOrError = createInstructionRenderer(InsertPt, M, Dst);
 
   // TODO: Assert there's exactly one result.
 
   if (auto Error = InsertPtOrError.takeError())
     return std::move(Error);
 
   BuildMIAction &DstMIBuilder =
       *static_cast<BuildMIAction *>(InsertPtOrError.get()->get());
 
   // Assign the result to TempReg.
   DstMIBuilder.addRenderer<TempRegRenderer>(TempRegID, true);
 
   InsertPtOrError =
       importExplicitUseRenderers(InsertPtOrError.get(), M, DstMIBuilder, Dst);
   if (auto Error = InsertPtOrError.takeError())
     return std::move(Error);
 
   M.insertAction<ConstrainOperandsToDefinitionAction>(InsertPt,
                                                       DstMIBuilder.getInsnID());
   return InsertPtOrError.get();
 }
 
 Expected<action_iterator> GlobalISelEmitter::createInstructionRenderer(
     action_iterator InsertPt, RuleMatcher &M, const TreePatternNode *Dst) {
   Record *DstOp = Dst->getOperator();
   if (!DstOp->isSubClassOf("Instruction")) {
     if (DstOp->isSubClassOf("ValueType"))
       return failedImport(
           "Pattern operator isn't an instruction (it's a ValueType)");
     return failedImport("Pattern operator isn't an instruction");
   }
   CodeGenInstruction *DstI = &Target.getInstruction(DstOp);
 
   // COPY_TO_REGCLASS is just a copy with a ConstrainOperandToRegClassAction
   // attached. Similarly for EXTRACT_SUBREG except that's a subregister copy.
   if (DstI->TheDef->getName() == "COPY_TO_REGCLASS")
     DstI = &Target.getInstruction(RK.getDef("COPY"));
   else if (DstI->TheDef->getName() == "EXTRACT_SUBREG")
     DstI = &Target.getInstruction(RK.getDef("COPY"));
   else if (DstI->TheDef->getName() == "REG_SEQUENCE")
     return failedImport("Unable to emit REG_SEQUENCE");
 
   return M.insertAction<BuildMIAction>(InsertPt, M.allocateOutputInsnID(),
                                        DstI);
 }
 
 void GlobalISelEmitter::importExplicitDefRenderers(
     BuildMIAction &DstMIBuilder) {
   const CodeGenInstruction *DstI = DstMIBuilder.getCGI();
   for (unsigned I = 0; I < DstI->Operands.NumDefs; ++I) {
     const CGIOperandList::OperandInfo &DstIOperand = DstI->Operands[I];
     DstMIBuilder.addRenderer<CopyRenderer>(DstIOperand.Name);
   }
 }
 
 Expected<action_iterator> GlobalISelEmitter::importExplicitUseRenderers(
     action_iterator InsertPt, RuleMatcher &M, BuildMIAction &DstMIBuilder,
     const llvm::TreePatternNode *Dst) {
   const CodeGenInstruction *DstI = DstMIBuilder.getCGI();
   CodeGenInstruction *OrigDstI = &Target.getInstruction(Dst->getOperator());
 
   // EXTRACT_SUBREG needs to use a subregister COPY.
   if (OrigDstI->TheDef->getName() == "EXTRACT_SUBREG") {
     if (!Dst->getChild(0)->isLeaf())
       return failedImport("EXTRACT_SUBREG child #1 is not a leaf");
 
     if (DefInit *SubRegInit =
             dyn_cast<DefInit>(Dst->getChild(1)->getLeafValue())) {
       Record *RCDef = getInitValueAsRegClass(Dst->getChild(0)->getLeafValue());
       if (!RCDef)
         return failedImport("EXTRACT_SUBREG child #0 could not "
                             "be coerced to a register class");
 
       CodeGenRegisterClass *RC = CGRegs.getRegClass(RCDef);
       CodeGenSubRegIndex *SubIdx = CGRegs.getSubRegIdx(SubRegInit->getDef());
 
       const auto &SrcRCDstRCPair =
           RC->getMatchingSubClassWithSubRegs(CGRegs, SubIdx);
       if (SrcRCDstRCPair.hasValue()) {
         assert(SrcRCDstRCPair->second && "Couldn't find a matching subclass");
         if (SrcRCDstRCPair->first != RC)
           return failedImport("EXTRACT_SUBREG requires an additional COPY");
       }
 
       DstMIBuilder.addRenderer<CopySubRegRenderer>(Dst->getChild(0)->getName(),
                                                    SubIdx);
       return InsertPt;
     }
 
     return failedImport("EXTRACT_SUBREG child #1 is not a subreg index");
   }
 
   // Render the explicit uses.
   unsigned DstINumUses = OrigDstI->Operands.size() - OrigDstI->Operands.NumDefs;
   unsigned ExpectedDstINumUses = Dst->getNumChildren();
   if (OrigDstI->TheDef->getName() == "COPY_TO_REGCLASS") {
     DstINumUses--; // Ignore the class constraint.
     ExpectedDstINumUses--;
   }
 
   unsigned Child = 0;
   unsigned NumDefaultOps = 0;
   for (unsigned I = 0; I != DstINumUses; ++I) {
     const CGIOperandList::OperandInfo &DstIOperand =
         DstI->Operands[DstI->Operands.NumDefs + I];
 
     // If the operand has default values, introduce them now.
     // FIXME: Until we have a decent test case that dictates we should do
     // otherwise, we're going to assume that operands with default values cannot
     // be specified in the patterns. Therefore, adding them will not cause us to
     // end up with too many rendered operands.
     if (DstIOperand.Rec->isSubClassOf("OperandWithDefaultOps")) {
       DagInit *DefaultOps = DstIOperand.Rec->getValueAsDag("DefaultOps");
       if (auto Error = importDefaultOperandRenderers(DstMIBuilder, DefaultOps))
         return std::move(Error);
       ++NumDefaultOps;
       continue;
     }
 
     auto InsertPtOrError = importExplicitUseRenderer(InsertPt, M, DstMIBuilder,
                                                      Dst->getChild(Child));
     if (auto Error = InsertPtOrError.takeError())
       return std::move(Error);
     InsertPt = InsertPtOrError.get();
     ++Child;
   }
 
   if (NumDefaultOps + ExpectedDstINumUses != DstINumUses)
     return failedImport("Expected " + llvm::to_string(DstINumUses) +
                         " used operands but found " +
                         llvm::to_string(ExpectedDstINumUses) +
                         " explicit ones and " + llvm::to_string(NumDefaultOps) +
                         " default ones");
 
   return InsertPt;
 }
 
 Error GlobalISelEmitter::importDefaultOperandRenderers(
     BuildMIAction &DstMIBuilder, DagInit *DefaultOps) const {
   for (const auto *DefaultOp : DefaultOps->getArgs()) {
     // Look through ValueType operators.
     if (const DagInit *DefaultDagOp = dyn_cast<DagInit>(DefaultOp)) {
       if (const DefInit *DefaultDagOperator =
               dyn_cast<DefInit>(DefaultDagOp->getOperator())) {
         if (DefaultDagOperator->getDef()->isSubClassOf("ValueType"))
           DefaultOp = DefaultDagOp->getArg(0);
       }
     }
 
     if (const DefInit *DefaultDefOp = dyn_cast<DefInit>(DefaultOp)) {
       DstMIBuilder.addRenderer<AddRegisterRenderer>(DefaultDefOp->getDef());
       continue;
     }
 
     if (const IntInit *DefaultIntOp = dyn_cast<IntInit>(DefaultOp)) {
       DstMIBuilder.addRenderer<ImmRenderer>(DefaultIntOp->getValue());
       continue;
     }
 
     return failedImport("Could not add default op");
   }
 
   return Error::success();
 }
 
 Error GlobalISelEmitter::importImplicitDefRenderers(
     BuildMIAction &DstMIBuilder,
     const std::vector<Record *> &ImplicitDefs) const {
   if (!ImplicitDefs.empty())
     return failedImport("Pattern defines a physical register");
   return Error::success();
 }
 
 Expected<RuleMatcher> GlobalISelEmitter::runOnPattern(const PatternToMatch &P) {
   // Keep track of the matchers and actions to emit.
   int Score = P.getPatternComplexity(CGP);
   RuleMatcher M(P.getSrcRecord()->getLoc());
   RuleMatcherScores[M.getRuleID()] = Score;
   M.addAction<DebugCommentAction>(llvm::to_string(*P.getSrcPattern()) +
                                   "  =>  " +
                                   llvm::to_string(*P.getDstPattern()));
 
   if (auto Error = importRulePredicates(M, P.getPredicates()))
     return std::move(Error);
 
   // Next, analyze the pattern operators.
   TreePatternNode *Src = P.getSrcPattern();
   TreePatternNode *Dst = P.getDstPattern();
 
   // If the root of either pattern isn't a simple operator, ignore it.
   if (auto Err = isTrivialOperatorNode(Dst))
     return failedImport("Dst pattern root isn't a trivial operator (" +
                         toString(std::move(Err)) + ")");
   if (auto Err = isTrivialOperatorNode(Src))
     return failedImport("Src pattern root isn't a trivial operator (" +
                         toString(std::move(Err)) + ")");
 
   // The different predicates and matchers created during
   // addInstructionMatcher use the RuleMatcher M to set up their
   // instruction ID (InsnVarID) that are going to be used when
   // M is going to be emitted.
   // However, the code doing the emission still relies on the IDs
   // returned during that process by the RuleMatcher when issuing
   // the recordInsn opcodes.
   // Because of that:
   // 1. The order in which we created the predicates
   //    and such must be the same as the order in which we emit them,
   //    and
   // 2. We need to reset the generation of the IDs in M somewhere between
   //    addInstructionMatcher and emit
   //
   // FIXME: Long term, we don't want to have to rely on this implicit
   // naming being the same. One possible solution would be to have
   // explicit operator for operation capture and reference those.
   // The plus side is that it would expose opportunities to share
   // the capture accross rules. The downside is that it would
   // introduce a dependency between predicates (captures must happen
   // before their first use.)
   InstructionMatcher &InsnMatcherTemp = M.addInstructionMatcher(Src->getName());
   unsigned TempOpIdx = 0;
   auto InsnMatcherOrError =
       createAndImportSelDAGMatcher(M, InsnMatcherTemp, Src, TempOpIdx);
   if (auto Error = InsnMatcherOrError.takeError())
     return std::move(Error);
   InstructionMatcher &InsnMatcher = InsnMatcherOrError.get();
 
   if (Dst->isLeaf()) {
     Record *RCDef = getInitValueAsRegClass(Dst->getLeafValue());
 
     const CodeGenRegisterClass &RC = Target.getRegisterClass(RCDef);
     if (RCDef) {
       // We need to replace the def and all its uses with the specified
       // operand. However, we must also insert COPY's wherever needed.
       // For now, emit a copy and let the register allocator clean up.
       auto &DstI = Target.getInstruction(RK.getDef("COPY"));
       const auto &DstIOperand = DstI.Operands[0];
 
       OperandMatcher &OM0 = InsnMatcher.getOperand(0);
       OM0.setSymbolicName(DstIOperand.Name);
       M.defineOperand(OM0.getSymbolicName(), OM0);
       OM0.addPredicate<RegisterBankOperandMatcher>(RC);
 
       auto &DstMIBuilder =
           M.addAction<BuildMIAction>(M.allocateOutputInsnID(), &DstI);
       DstMIBuilder.addRenderer<CopyRenderer>(DstIOperand.Name);
       DstMIBuilder.addRenderer<CopyRenderer>(Dst->getName());
       M.addAction<ConstrainOperandToRegClassAction>(0, 0, RC);
 
       // We're done with this pattern!  It's eligible for GISel emission; return
       // it.
       ++NumPatternImported;
       return std::move(M);
     }
 
     return failedImport("Dst pattern root isn't a known leaf");
   }
 
   // Start with the defined operands (i.e., the results of the root operator).
   Record *DstOp = Dst->getOperator();
   if (!DstOp->isSubClassOf("Instruction"))
     return failedImport("Pattern operator isn't an instruction");
 
   auto &DstI = Target.getInstruction(DstOp);
   if (DstI.Operands.NumDefs != Src->getExtTypes().size())
     return failedImport("Src pattern results and dst MI defs are different (" +
                         to_string(Src->getExtTypes().size()) + " def(s) vs " +
                         to_string(DstI.Operands.NumDefs) + " def(s))");
 
   // The root of the match also has constraints on the register bank so that it
   // matches the result instruction.
   unsigned OpIdx = 0;
   for (const TypeSetByHwMode &VTy : Src->getExtTypes()) {
     (void)VTy;
 
     const auto &DstIOperand = DstI.Operands[OpIdx];
     Record *DstIOpRec = DstIOperand.Rec;
     if (DstI.TheDef->getName() == "COPY_TO_REGCLASS") {
       DstIOpRec = getInitValueAsRegClass(Dst->getChild(1)->getLeafValue());
 
       if (DstIOpRec == nullptr)
         return failedImport(
             "COPY_TO_REGCLASS operand #1 isn't a register class");
     } else if (DstI.TheDef->getName() == "EXTRACT_SUBREG") {
       if (!Dst->getChild(0)->isLeaf())
         return failedImport("EXTRACT_SUBREG operand #0 isn't a leaf");
 
       // We can assume that a subregister is in the same bank as it's super
       // register.
       DstIOpRec = getInitValueAsRegClass(Dst->getChild(0)->getLeafValue());
 
       if (DstIOpRec == nullptr)
         return failedImport(
             "EXTRACT_SUBREG operand #0 isn't a register class");
     } else if (DstIOpRec->isSubClassOf("RegisterOperand"))
       DstIOpRec = DstIOpRec->getValueAsDef("RegClass");
     else if (!DstIOpRec->isSubClassOf("RegisterClass"))
       return failedImport("Dst MI def isn't a register class" +
                           to_string(*Dst));
 
     OperandMatcher &OM = InsnMatcher.getOperand(OpIdx);
     OM.setSymbolicName(DstIOperand.Name);
     M.defineOperand(OM.getSymbolicName(), OM);
     OM.addPredicate<RegisterBankOperandMatcher>(
         Target.getRegisterClass(DstIOpRec));
     ++OpIdx;
   }
 
   auto DstMIBuilderOrError = createAndImportInstructionRenderer(M, Dst);
   if (auto Error = DstMIBuilderOrError.takeError())
     return std::move(Error);
   BuildMIAction &DstMIBuilder = DstMIBuilderOrError.get();
 
   // Render the implicit defs.
   // These are only added to the root of the result.
   if (auto Error = importImplicitDefRenderers(DstMIBuilder, P.getDstRegs()))
     return std::move(Error);
 
   DstMIBuilder.chooseInsnToMutate(M);
 
   // Constrain the registers to classes. This is normally derived from the
   // emitted instruction but a few instructions require special handling.
   if (DstI.TheDef->getName() == "COPY_TO_REGCLASS") {
     // COPY_TO_REGCLASS does not provide operand constraints itself but the
     // result is constrained to the class given by the second child.
     Record *DstIOpRec =
         getInitValueAsRegClass(Dst->getChild(1)->getLeafValue());
 
     if (DstIOpRec == nullptr)
       return failedImport("COPY_TO_REGCLASS operand #1 isn't a register class");
 
     M.addAction<ConstrainOperandToRegClassAction>(
         0, 0, Target.getRegisterClass(DstIOpRec));
 
     // We're done with this pattern!  It's eligible for GISel emission; return
     // it.
     ++NumPatternImported;
     return std::move(M);
   }
 
   if (DstI.TheDef->getName() == "EXTRACT_SUBREG") {
     // EXTRACT_SUBREG selects into a subregister COPY but unlike most
     // instructions, the result register class is controlled by the
     // subregisters of the operand. As a result, we must constrain the result
     // class rather than check that it's already the right one.
     if (!Dst->getChild(0)->isLeaf())
       return failedImport("EXTRACT_SUBREG child #1 is not a leaf");
 
     DefInit *SubRegInit = dyn_cast<DefInit>(Dst->getChild(1)->getLeafValue());
     if (!SubRegInit)
       return failedImport("EXTRACT_SUBREG child #1 is not a subreg index");
 
     // Constrain the result to the same register bank as the operand.
     Record *DstIOpRec =
         getInitValueAsRegClass(Dst->getChild(0)->getLeafValue());
 
     if (DstIOpRec == nullptr)
       return failedImport("EXTRACT_SUBREG operand #1 isn't a register class");
 
     CodeGenSubRegIndex *SubIdx = CGRegs.getSubRegIdx(SubRegInit->getDef());
     CodeGenRegisterClass *SrcRC = CGRegs.getRegClass(DstIOpRec);
 
     // It would be nice to leave this constraint implicit but we're required
     // to pick a register class so constrain the result to a register class
     // that can hold the correct MVT.
     //
     // FIXME: This may introduce an extra copy if the chosen class doesn't
     //        actually contain the subregisters.
     assert(Src->getExtTypes().size() == 1 &&
              "Expected Src of EXTRACT_SUBREG to have one result type");
 
     const auto &SrcRCDstRCPair =
         SrcRC->getMatchingSubClassWithSubRegs(CGRegs, SubIdx);
     assert(SrcRCDstRCPair->second && "Couldn't find a matching subclass");
     M.addAction<ConstrainOperandToRegClassAction>(0, 0, *SrcRCDstRCPair->second);
     M.addAction<ConstrainOperandToRegClassAction>(0, 1, *SrcRCDstRCPair->first);
 
     // We're done with this pattern!  It's eligible for GISel emission; return
     // it.
     ++NumPatternImported;
     return std::move(M);
   }
 
   M.addAction<ConstrainOperandsToDefinitionAction>(0);
 
   // We're done with this pattern!  It's eligible for GISel emission; return it.
   ++NumPatternImported;
   return std::move(M);
 }
 
 // Emit imm predicate table and an enum to reference them with.
 // The 'Predicate_' part of the name is redundant but eliminating it is more
 // trouble than it's worth.
 void GlobalISelEmitter::emitImmPredicates(
     raw_ostream &OS, StringRef TypeIdentifier, StringRef Type,
     std::function<bool(const Record *R)> Filter) {
   std::vector<const Record *> MatchedRecords;
   const auto &Defs = RK.getAllDerivedDefinitions("PatFrag");
   std::copy_if(Defs.begin(), Defs.end(), std::back_inserter(MatchedRecords),
                [&](Record *Record) {
                  return !Record->getValueAsString("ImmediateCode").empty() &&
                         Filter(Record);
                });
 
   if (!MatchedRecords.empty()) {
     OS << "// PatFrag predicates.\n"
        << "enum {\n";
     std::string EnumeratorSeparator =
         (" = GIPFP_" + TypeIdentifier + "_Invalid + 1,\n").str();
     for (const auto *Record : MatchedRecords) {
       OS << "  GIPFP_" << TypeIdentifier << "_Predicate_" << Record->getName()
          << EnumeratorSeparator;
       EnumeratorSeparator = ",\n";
     }
     OS << "};\n";
   }
 
   OS << "bool " << Target.getName() << "InstructionSelector::testImmPredicate_"
      << TypeIdentifier << "(unsigned PredicateID, " << Type
      << " Imm) const {\n";
   if (!MatchedRecords.empty())
     OS << "  switch (PredicateID) {\n";
   for (const auto *Record : MatchedRecords) {
     OS << "  case GIPFP_" << TypeIdentifier << "_Predicate_"
        << Record->getName() << ": {\n"
        << "    " << Record->getValueAsString("ImmediateCode") << "\n"
        << "    llvm_unreachable(\"ImmediateCode should have returned\");\n"
        << "    return false;\n"
        << "  }\n";
   }
   if (!MatchedRecords.empty())
     OS << "  }\n";
   OS << "  llvm_unreachable(\"Unknown predicate\");\n"
      << "  return false;\n"
      << "}\n";
 }
 
 template <class GroupT>
 std::vector<Matcher *> GlobalISelEmitter::optimizeRules(
     ArrayRef<Matcher *> Rules,
     std::vector<std::unique_ptr<Matcher>> &MatcherStorage) {
 
   std::vector<Matcher *> OptRules;
   std::unique_ptr<GroupT> CurrentGroup = make_unique<GroupT>();
   assert(CurrentGroup->empty() && "Newly created group isn't empty!");
   unsigned NumGroups = 0;
 
   auto ProcessCurrentGroup = [&]() {
     if (CurrentGroup->empty())
       // An empty group is good to be reused:
       return;
 
     // If the group isn't large enough to provide any benefit, move all the
     // added rules out of it and make sure to re-create the group to properly
     // re-initialize it:
     if (CurrentGroup->size() < 2)
       for (Matcher *M : CurrentGroup->matchers())
         OptRules.push_back(M);
     else {
       CurrentGroup->finalize();
       OptRules.push_back(CurrentGroup.get());
       MatcherStorage.emplace_back(std::move(CurrentGroup));
       ++NumGroups;
     }
     CurrentGroup = make_unique<GroupT>();
   };
   for (Matcher *Rule : Rules) {
     // Greedily add as many matchers as possible to the current group:
     if (CurrentGroup->addMatcher(*Rule))
       continue;
 
     ProcessCurrentGroup();
     assert(CurrentGroup->empty() && "A group wasn't properly re-initialized");
 
     // Try to add the pending matcher to a newly created empty group:
     if (!CurrentGroup->addMatcher(*Rule))
       // If we couldn't add the matcher to an empty group, that group type
       // doesn't support that kind of matchers at all, so just skip it:
       OptRules.push_back(Rule);
   }
   ProcessCurrentGroup();
 
   DEBUG(dbgs() << "NumGroups: " << NumGroups << "\n");
   assert(CurrentGroup->empty() && "The last group wasn't properly processed");
   return OptRules;
 }
 
 MatchTable
 GlobalISelEmitter::buildMatchTable(MutableArrayRef<RuleMatcher> Rules,
                                    bool Optimize, bool WithCoverage) {
   std::vector<Matcher *> InputRules;
   for (Matcher &Rule : Rules)
     InputRules.push_back(&Rule);
 
   if (!Optimize)
     return MatchTable::buildTable(InputRules, WithCoverage);
 
+  unsigned CurrentOrdering = 0;
+  StringMap<unsigned> OpcodeOrder;
+  for (RuleMatcher &Rule : Rules) {
+    const StringRef Opcode = Rule.getOpcode();
+    assert(!Opcode.empty() && "Didn't expect an undefined opcode");
+    if (OpcodeOrder.count(Opcode) == 0)
+      OpcodeOrder[Opcode] = CurrentOrdering++;
+  }
+
+  std::stable_sort(InputRules.begin(), InputRules.end(),
+                   [&OpcodeOrder](const Matcher *A, const Matcher *B) {
+                     auto *L = static_cast<const RuleMatcher *>(A);
+                     auto *R = static_cast<const RuleMatcher *>(B);
+                     return std::make_tuple(OpcodeOrder[L->getOpcode()],
+                                            L->getNumOperands()) <
+                            std::make_tuple(OpcodeOrder[R->getOpcode()],
+                                            R->getNumOperands());
+                   });
+
   for (Matcher *Rule : InputRules)
     Rule->optimize();
 
   std::vector<std::unique_ptr<Matcher>> MatcherStorage;
   std::vector<Matcher *> OptRules =
       optimizeRules<GroupMatcher>(InputRules, MatcherStorage);
 
   for (Matcher *Rule : OptRules)
     Rule->optimize();
 
   return MatchTable::buildTable(OptRules, WithCoverage);
 }
 
 void GlobalISelEmitter::run(raw_ostream &OS) {
   if (!UseCoverageFile.empty()) {
     RuleCoverage = CodeGenCoverage();
     auto RuleCoverageBufOrErr = MemoryBuffer::getFile(UseCoverageFile);
     if (!RuleCoverageBufOrErr) {
       PrintWarning(SMLoc(), "Missing rule coverage data");
       RuleCoverage = None;
     } else {
       if (!RuleCoverage->parse(*RuleCoverageBufOrErr.get(), Target.getName())) {
         PrintWarning(SMLoc(), "Ignoring invalid or missing rule coverage data");
         RuleCoverage = None;
       }
     }
   }
 
   // Track the run-time opcode values
   gatherOpcodeValues();
   // Track the run-time LLT ID values
   gatherTypeIDValues();
 
   // Track the GINodeEquiv definitions.
   gatherNodeEquivs();
 
   emitSourceFileHeader(("Global Instruction Selector for the " +
                        Target.getName() + " target").str(), OS);
   std::vector<RuleMatcher> Rules;
   // Look through the SelectionDAG patterns we found, possibly emitting some.
   for (const PatternToMatch &Pat : CGP.ptms()) {
     ++NumPatternTotal;
 
     auto MatcherOrErr = runOnPattern(Pat);
 
     // The pattern analysis can fail, indicating an unsupported pattern.
     // Report that if we've been asked to do so.
     if (auto Err = MatcherOrErr.takeError()) {
       if (WarnOnSkippedPatterns) {
         PrintWarning(Pat.getSrcRecord()->getLoc(),
                      "Skipped pattern: " + toString(std::move(Err)));
       } else {
         consumeError(std::move(Err));
       }
       ++NumPatternImportsSkipped;
       continue;
     }
 
     if (RuleCoverage) {
       if (RuleCoverage->isCovered(MatcherOrErr->getRuleID()))
         ++NumPatternsTested;
       else
         PrintWarning(Pat.getSrcRecord()->getLoc(),
                      "Pattern is not covered by a test");
     }
     Rules.push_back(std::move(MatcherOrErr.get()));
   }
 
   // Comparison function to order records by name.
   auto orderByName = [](const Record *A, const Record *B) {
     return A->getName() < B->getName();
   };
 
   std::vector<Record *> ComplexPredicates =
       RK.getAllDerivedDefinitions("GIComplexOperandMatcher");
   llvm::sort(ComplexPredicates.begin(), ComplexPredicates.end(), orderByName);
 
   std::vector<Record *> CustomRendererFns =
       RK.getAllDerivedDefinitions("GICustomOperandRenderer");
   llvm::sort(CustomRendererFns.begin(), CustomRendererFns.end(), orderByName);
 
   unsigned MaxTemporaries = 0;
   for (const auto &Rule : Rules)
     MaxTemporaries = std::max(MaxTemporaries, Rule.countRendererFns());
 
   OS << "#ifdef GET_GLOBALISEL_PREDICATE_BITSET\n"
      << "const unsigned MAX_SUBTARGET_PREDICATES = " << SubtargetFeatures.size()
      << ";\n"
      << "using PredicateBitset = "
         "llvm::PredicateBitsetImpl<MAX_SUBTARGET_PREDICATES>;\n"
      << "#endif // ifdef GET_GLOBALISEL_PREDICATE_BITSET\n\n";
 
   OS << "#ifdef GET_GLOBALISEL_TEMPORARIES_DECL\n"
      << "  mutable MatcherState State;\n"
      << "  typedef "
         "ComplexRendererFns("
      << Target.getName()
      << "InstructionSelector::*ComplexMatcherMemFn)(MachineOperand &) const;\n"
 
      << "  typedef void(" << Target.getName()
      << "InstructionSelector::*CustomRendererFn)(MachineInstrBuilder &, const "
         "MachineInstr&) "
         "const;\n"
      << "  const ISelInfoTy<PredicateBitset, ComplexMatcherMemFn, "
         "CustomRendererFn> "
         "ISelInfo;\n";
   OS << "  static " << Target.getName()
      << "InstructionSelector::ComplexMatcherMemFn ComplexPredicateFns[];\n"
      << "  static " << Target.getName()
      << "InstructionSelector::CustomRendererFn CustomRenderers[];\n"
      << "  bool testImmPredicate_I64(unsigned PredicateID, int64_t Imm) const "
         "override;\n"
      << "  bool testImmPredicate_APInt(unsigned PredicateID, const APInt &Imm) "
         "const override;\n"
      << "  bool testImmPredicate_APFloat(unsigned PredicateID, const APFloat "
         "&Imm) const override;\n"
      << "  const int64_t *getMatchTable() const override;\n"
      << "#endif // ifdef GET_GLOBALISEL_TEMPORARIES_DECL\n\n";
 
   OS << "#ifdef GET_GLOBALISEL_TEMPORARIES_INIT\n"
      << ", State(" << MaxTemporaries << "),\n"
      << "ISelInfo(TypeObjects, NumTypeObjects, FeatureBitsets"
      << ", ComplexPredicateFns, CustomRenderers)\n"
      << "#endif // ifdef GET_GLOBALISEL_TEMPORARIES_INIT\n\n";
 
   OS << "#ifdef GET_GLOBALISEL_IMPL\n";
   SubtargetFeatureInfo::emitSubtargetFeatureBitEnumeration(SubtargetFeatures,
                                                            OS);
 
   // Separate subtarget features by how often they must be recomputed.
   SubtargetFeatureInfoMap ModuleFeatures;
   std::copy_if(SubtargetFeatures.begin(), SubtargetFeatures.end(),
                std::inserter(ModuleFeatures, ModuleFeatures.end()),
                [](const SubtargetFeatureInfoMap::value_type &X) {
                  return !X.second.mustRecomputePerFunction();
                });
   SubtargetFeatureInfoMap FunctionFeatures;
   std::copy_if(SubtargetFeatures.begin(), SubtargetFeatures.end(),
                std::inserter(FunctionFeatures, FunctionFeatures.end()),
                [](const SubtargetFeatureInfoMap::value_type &X) {
                  return X.second.mustRecomputePerFunction();
                });
 
   SubtargetFeatureInfo::emitComputeAvailableFeatures(
       Target.getName(), "InstructionSelector", "computeAvailableModuleFeatures",
       ModuleFeatures, OS);
   SubtargetFeatureInfo::emitComputeAvailableFeatures(
       Target.getName(), "InstructionSelector",
       "computeAvailableFunctionFeatures", FunctionFeatures, OS,
       "const MachineFunction *MF");
 
   // Emit a table containing the LLT objects needed by the matcher and an enum
   // for the matcher to reference them with.
   std::vector<LLTCodeGen> TypeObjects;
   for (const auto &Ty : KnownTypes)
     TypeObjects.push_back(Ty);
   llvm::sort(TypeObjects.begin(), TypeObjects.end());
   OS << "// LLT Objects.\n"
      << "enum {\n";
   for (const auto &TypeObject : TypeObjects) {
     OS << "  ";
     TypeObject.emitCxxEnumValue(OS);
     OS << ",\n";
   }
   OS << "};\n";
   OS << "const static size_t NumTypeObjects = " << TypeObjects.size() << ";\n"
      << "const static LLT TypeObjects[] = {\n";
   for (const auto &TypeObject : TypeObjects) {
     OS << "  ";
     TypeObject.emitCxxConstructorCall(OS);
     OS << ",\n";
   }
   OS << "};\n\n";
 
   // Emit a table containing the PredicateBitsets objects needed by the matcher
   // and an enum for the matcher to reference them with.
   std::vector<std::vector<Record *>> FeatureBitsets;
   for (auto &Rule : Rules)
     FeatureBitsets.push_back(Rule.getRequiredFeatures());
   llvm::sort(
       FeatureBitsets.begin(), FeatureBitsets.end(),
       [&](const std::vector<Record *> &A, const std::vector<Record *> &B) {
         if (A.size() < B.size())
           return true;
         if (A.size() > B.size())
           return false;
         for (const auto &Pair : zip(A, B)) {
           if (std::get<0>(Pair)->getName() < std::get<1>(Pair)->getName())
             return true;
           if (std::get<0>(Pair)->getName() > std::get<1>(Pair)->getName())
             return false;
         }
         return false;
       });
   FeatureBitsets.erase(
       std::unique(FeatureBitsets.begin(), FeatureBitsets.end()),
       FeatureBitsets.end());
   OS << "// Feature bitsets.\n"
      << "enum {\n"
      << "  GIFBS_Invalid,\n";
   for (const auto &FeatureBitset : FeatureBitsets) {
     if (FeatureBitset.empty())
       continue;
     OS << "  " << getNameForFeatureBitset(FeatureBitset) << ",\n";
   }
   OS << "};\n"
      << "const static PredicateBitset FeatureBitsets[] {\n"
      << "  {}, // GIFBS_Invalid\n";
   for (const auto &FeatureBitset : FeatureBitsets) {
     if (FeatureBitset.empty())
       continue;
     OS << "  {";
     for (const auto &Feature : FeatureBitset) {
       const auto &I = SubtargetFeatures.find(Feature);
       assert(I != SubtargetFeatures.end() && "Didn't import predicate?");
       OS << I->second.getEnumBitName() << ", ";
     }
     OS << "},\n";
   }
   OS << "};\n\n";
 
   // Emit complex predicate table and an enum to reference them with.
   OS << "// ComplexPattern predicates.\n"
      << "enum {\n"
      << "  GICP_Invalid,\n";
   for (const auto &Record : ComplexPredicates)
     OS << "  GICP_" << Record->getName() << ",\n";
   OS << "};\n"
      << "// See constructor for table contents\n\n";
 
   emitImmPredicates(OS, "I64", "int64_t", [](const Record *R) {
     bool Unset;
     return !R->getValueAsBitOrUnset("IsAPFloat", Unset) &&
            !R->getValueAsBit("IsAPInt");
   });
   emitImmPredicates(OS, "APFloat", "const APFloat &", [](const Record *R) {
     bool Unset;
     return R->getValueAsBitOrUnset("IsAPFloat", Unset);
   });
   emitImmPredicates(OS, "APInt", "const APInt &", [](const Record *R) {
     return R->getValueAsBit("IsAPInt");
   });
   OS << "\n";
 
   OS << Target.getName() << "InstructionSelector::ComplexMatcherMemFn\n"
      << Target.getName() << "InstructionSelector::ComplexPredicateFns[] = {\n"
      << "  nullptr, // GICP_Invalid\n";
   for (const auto &Record : ComplexPredicates)
     OS << "  &" << Target.getName()
        << "InstructionSelector::" << Record->getValueAsString("MatcherFn")
        << ", // " << Record->getName() << "\n";
   OS << "};\n\n";
 
   OS << "// Custom renderers.\n"
      << "enum {\n"
      << "  GICR_Invalid,\n";
   for (const auto &Record : CustomRendererFns)
     OS << "  GICR_" << Record->getValueAsString("RendererFn") << ", \n";
   OS << "};\n";
 
   OS << Target.getName() << "InstructionSelector::CustomRendererFn\n"
      << Target.getName() << "InstructionSelector::CustomRenderers[] = {\n"
      << "  nullptr, // GICP_Invalid\n";
   for (const auto &Record : CustomRendererFns)
     OS << "  &" << Target.getName()
        << "InstructionSelector::" << Record->getValueAsString("RendererFn")
        << ", // " << Record->getName() << "\n";
   OS << "};\n\n";
 
   std::stable_sort(Rules.begin(), Rules.end(), [&](const RuleMatcher &A,
                                                    const RuleMatcher &B) {
     int ScoreA = RuleMatcherScores[A.getRuleID()];
     int ScoreB = RuleMatcherScores[B.getRuleID()];
     if (ScoreA > ScoreB)
       return true;
     if (ScoreB > ScoreA)
       return false;
     if (A.isHigherPriorityThan(B)) {
       assert(!B.isHigherPriorityThan(A) && "Cannot be more important "
                                            "and less important at "
                                            "the same time");
       return true;
     }
     return false;
   });
 
   OS << "bool " << Target.getName()
      << "InstructionSelector::selectImpl(MachineInstr &I, CodeGenCoverage "
         "&CoverageInfo) const {\n"
      << "  MachineFunction &MF = *I.getParent()->getParent();\n"
      << "  MachineRegisterInfo &MRI = MF.getRegInfo();\n"
      << "  // FIXME: This should be computed on a per-function basis rather "
         "than per-insn.\n"
      << "  AvailableFunctionFeatures = computeAvailableFunctionFeatures(&STI, "
         "&MF);\n"
      << "  const PredicateBitset AvailableFeatures = getAvailableFeatures();\n"
      << "  NewMIVector OutMIs;\n"
      << "  State.MIs.clear();\n"
      << "  State.MIs.push_back(&I);\n\n"
      << "  if (executeMatchTable(*this, OutMIs, State, ISelInfo"
      << ", getMatchTable(), TII, MRI, TRI, RBI, AvailableFeatures"
      << ", CoverageInfo)) {\n"
      << "    return true;\n"
      << "  }\n\n"
      << "  return false;\n"
      << "}\n\n";
 
   const MatchTable Table =
       buildMatchTable(Rules, OptimizeMatchTable, GenerateCoverage);
   OS << "const int64_t *" << Target.getName()
      << "InstructionSelector::getMatchTable() const {\n";
   Table.emitDeclaration(OS);
   OS << "  return ";
   Table.emitUse(OS);
   OS << ";\n}\n";
   OS << "#endif // ifdef GET_GLOBALISEL_IMPL\n";
 
   OS << "#ifdef GET_GLOBALISEL_PREDICATES_DECL\n"
      << "PredicateBitset AvailableModuleFeatures;\n"
      << "mutable PredicateBitset AvailableFunctionFeatures;\n"
      << "PredicateBitset getAvailableFeatures() const {\n"
      << "  return AvailableModuleFeatures | AvailableFunctionFeatures;\n"
      << "}\n"
      << "PredicateBitset\n"
      << "computeAvailableModuleFeatures(const " << Target.getName()
      << "Subtarget *Subtarget) const;\n"
      << "PredicateBitset\n"
      << "computeAvailableFunctionFeatures(const " << Target.getName()
      << "Subtarget *Subtarget,\n"
      << "                                 const MachineFunction *MF) const;\n"
      << "#endif // ifdef GET_GLOBALISEL_PREDICATES_DECL\n";
 
   OS << "#ifdef GET_GLOBALISEL_PREDICATES_INIT\n"
      << "AvailableModuleFeatures(computeAvailableModuleFeatures(&STI)),\n"
      << "AvailableFunctionFeatures()\n"
      << "#endif // ifdef GET_GLOBALISEL_PREDICATES_INIT\n";
 }
 
 void GlobalISelEmitter::declareSubtargetFeature(Record *Predicate) {
   if (SubtargetFeatures.count(Predicate) == 0)
     SubtargetFeatures.emplace(
         Predicate, SubtargetFeatureInfo(Predicate, SubtargetFeatures.size()));
 }
 
 void RuleMatcher::optimize() {
   for (auto &Item : InsnVariableIDs) {
     InstructionMatcher &InsnMatcher = *Item.first;
     for (auto &OM : InsnMatcher.operands()) {
       // Register Banks checks rarely fail, but often crash as targets usually
       // provide only partially defined RegisterBankInfo::getRegBankFromRegClass
       // method. Often the problem is hidden as non-optimized MatchTable checks
       // banks rather late, most notably after checking target / function /
       // module features and a few opcodes. That makes these checks a)
       // beneficial to delay until the very end (we don't want to perform a lot
       // of checks that all pass and then fail at the very end) b) not safe to
       // have as early checks.
       for (auto &OP : OM->predicates())
         if (isa<RegisterBankOperandMatcher>(OP) ||
             isa<ComplexPatternOperandMatcher>(OP))
           EpilogueMatchers.emplace_back(std::move(OP));
       OM->eraseNullPredicates();
     }
     InsnMatcher.optimize();
   }
   llvm::sort(
       EpilogueMatchers.begin(), EpilogueMatchers.end(),
       [](const std::unique_ptr<PredicateMatcher> &L,
          const std::unique_ptr<PredicateMatcher> &R) {
         return std::make_tuple(L->getKind(), L->getInsnVarID(), L->getOpIdx()) <
                std::make_tuple(R->getKind(), R->getInsnVarID(), R->getOpIdx());
       });
 }
 
 bool RuleMatcher::hasFirstCondition() const {
   if (insnmatchers_empty())
     return false;
   InstructionMatcher &Matcher = insnmatchers_front();
   if (!Matcher.predicates_empty())
     return true;
   for (auto &OM : Matcher.operands())
     for (auto &OP : OM->predicates())
       if (!isa<InstructionOperandMatcher>(OP))
         return true;
   return false;
 }
 
 const PredicateMatcher &RuleMatcher::getFirstCondition() const {
   assert(!insnmatchers_empty() &&
          "Trying to get a condition from an empty RuleMatcher");
 
   InstructionMatcher &Matcher = insnmatchers_front();
   if (!Matcher.predicates_empty())
     return **Matcher.predicates_begin();
   // If there is no more predicate on the instruction itself, look at its
   // operands.
   for (auto &OM : Matcher.operands())
     for (auto &OP : OM->predicates())
       if (!isa<InstructionOperandMatcher>(OP))
         return *OP;
 
   llvm_unreachable("Trying to get a condition from an InstructionMatcher with "
                    "no conditions");
 }
 
 std::unique_ptr<PredicateMatcher> RuleMatcher::popFirstCondition() {
   assert(!insnmatchers_empty() &&
          "Trying to pop a condition from an empty RuleMatcher");
 
   InstructionMatcher &Matcher = insnmatchers_front();
   if (!Matcher.predicates_empty())
     return Matcher.predicates_pop_front();
   // If there is no more predicate on the instruction itself, look at its
   // operands.
   for (auto &OM : Matcher.operands())
     for (auto &OP : OM->predicates())
       if (!isa<InstructionOperandMatcher>(OP)) {
         std::unique_ptr<PredicateMatcher> Result = std::move(OP);
         OM->eraseNullPredicates();
         return Result;
       }
 
   llvm_unreachable("Trying to pop a condition from an InstructionMatcher with "
                    "no conditions");
 }
 
 bool GroupMatcher::candidateConditionMatches(
     const PredicateMatcher &Predicate) const {
 
   if (empty()) {
     // Sharing predicates for nested instructions is not supported yet as we
     // currently don't hoist the GIM_RecordInsn's properly, therefore we can
     // only work on the original root instruction (InsnVarID == 0):
     if (Predicate.getInsnVarID() != 0)
       return false;
     // ... otherwise an empty group can handle any predicate with no specific
     // requirements:
     return true;
   }
 
   const Matcher &Representative = **Matchers.begin();
   const auto &RepresentativeCondition = Representative.getFirstCondition();
   // ... if not empty, the group can only accomodate matchers with the exact
   // same first condition:
   return Predicate.isIdentical(RepresentativeCondition);
 }
 
 bool GroupMatcher::addMatcher(Matcher &Candidate) {
   if (!Candidate.hasFirstCondition())
     return false;
 
   const PredicateMatcher &Predicate = Candidate.getFirstCondition();
   if (!candidateConditionMatches(Predicate))
     return false;
 
   Matchers.push_back(&Candidate);
   return true;
 }
 
 void GroupMatcher::finalize() {
   assert(Conditions.empty() && "Already finalized?");
   if (empty())
     return;
 
   Matcher &FirstRule = **Matchers.begin();
 
   Conditions.push_back(FirstRule.popFirstCondition());
   for (unsigned I = 1, E = Matchers.size(); I < E; ++I)
     Matchers[I]->popFirstCondition();
 }
 
 void GroupMatcher::emit(MatchTable &Table) {
   unsigned LabelID = ~0U;
   if (!Conditions.empty()) {
     LabelID = Table.allocateLabelID();
     Table << MatchTable::Opcode("GIM_Try", +1)
           << MatchTable::Comment("On fail goto")
           << MatchTable::JumpTarget(LabelID) << MatchTable::LineBreak;
   }
   for (auto &Condition : Conditions)
     Condition->emitPredicateOpcodes(
         Table, *static_cast<RuleMatcher *>(*Matchers.begin()));
 
   for (const auto &M : Matchers)
     M->emit(Table);
 
   // Exit the group
   if (!Conditions.empty())
     Table << MatchTable::Opcode("GIM_Reject", -1) << MatchTable::LineBreak
           << MatchTable::Label(LabelID);
 }
 
 unsigned OperandMatcher::getInsnVarID() const { return Insn.getInsnVarID(); }
 
 } // end anonymous namespace
 
 //===----------------------------------------------------------------------===//
 
 namespace llvm {
 void EmitGlobalISel(RecordKeeper &RK, raw_ostream &OS) {
   GlobalISelEmitter(RK).run(OS);
 }
 } // End llvm namespace

llvm-svn: 332999
2018-05-22 16:51:54 +00:00
Roman Tereshin 19da667599 [GlobalISel][InstructionSelect] Removing redundant num operands and nested def operands checks, perf patch 2
This patch continues a series of patches that decrease time spent by
GlobalISel in its InstructionSelect pass by roughly 60% for -O0 builds
for large inputs as measured on sqlite3-amalgamation
(http://sqlite.org/download.html) targeting AArch64.

This commit specifically removes number of operands checks that are
redundant if the instruction's opcode already guarantees that number
of operands (or more), and also avoids any kind of checks on a def
operand of a nested instruction as everything about it was already
checked at its use.

The expected performance implication is about 3% off InstructionSelect
comparing to the baseline (before the series of patches)

This patch also contains a bit of NFC changes required for further
patches in the series.

Every commit planned shares the same Phabricator Review.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 332945
2018-05-22 04:31:50 +00:00
Roman Tereshin f1aa348b31 Reapply r332907 "[GlobalISel] Improving InstructionSelect's performance by reducing MatchTable..."
Apparently the compile time problem was caused by the fact that not
all compilers / STL implementations can automatically convert
std::unique_ptr<Derived> to std::unique_ptr<Base>. Fixed (hopefully)
by making sure it's std::unique_ptr<Derived>&& (rvalue ref) to
std::unique_ptr<Base> conversion instead.

llvm-svn: 332917
2018-05-21 23:28:51 +00:00
Roman Tereshin 8bdf7be5bb Revert r332907 "[GlobalISel] Improving InstructionSelect's performance by reducing MatchTable..."
There is a compile time error I didn't see locally, investigating now.

llvm-svn: 332912
2018-05-21 22:21:24 +00:00
Roman Tereshin f0dc9fa934 [GlobalISel] Improving InstructionSelect's performance by reducing MatchTable, mostly NFC, perf patch 1
This patch starts a series of patches that decrease time spent by
GlobalISel in its InstructionSelect pass by roughly 60% for -O0 builds
for large inputs as measured on sqlite3-amalgamation
(http://sqlite.org/download.html) targeting AArch64.

The performance improvements are achieved solely by reducing the
number of matching GIM_* opcodes executed by the MatchTable's
interpreter during the selection by approx. a factor of 30, which also
brings contribution of this particular part of the selection process
to the overall runtime of InstructionSelect pass down from approx.
60-70% to 5-7%, thus making further improvements in this particular
direction not very profitable.

The improvements described above are expected for any target that
doesn't have many complex patterns. The targets that do should
strictly benefit from the changes, but by how much exactly is hard to
estimate beforehand. It's also likely that such target WILL benefit
from further improvements to MatchTable, most likely the ones that
bring it closer to a perfect decision tree.

This commit specifically is rather large mostly NFC commit that does
necessary preparation work and refactoring, there will be a following
series of small patches introducing a specific optimization each
shortly after.

This commit specifically is expected to cause a small compile time
regression (around 2.5% of InstructionSelect pass time), which should
be fixed by the next commit of the series.

Every commit planned shares the same Phabricator Review.

Reviewers: qcolombet, dsanders, bogner, aemerson, javed.absar

Reviewed By: qcolombet

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D44700

llvm-svn: 332907
2018-05-21 22:04:39 +00:00
Nicola Zaghen d34e60ca85 Rename DEBUG macro to LLVM_DEBUG.
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.

In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.

Differential Revision: https://reviews.llvm.org/D43624

llvm-svn: 332240
2018-05-14 12:53:11 +00:00
Daniel Sanders f84bc3793e [globalisel] Update GlobalISel emitter to match new representation of extending loads
Summary:
Previously, a extending load was represented at (G_*EXT (G_LOAD x)).
This had a few drawbacks:
* G_LOAD had to be legal for all sizes you could extend from, even if
  registers didn't naturally hold those sizes.
* All sizes you could extend from had to be allocatable just in case the
  extend went missing (e.g. by optimization).
* At minimum, G_*EXT and G_TRUNC had to be legal for these sizes. As we
  improve optimization of extends and truncates, this legality requirement
  would spread without considerable care w.r.t when certain combines were
  permitted.
* The SelectionDAG importer required some ugly and fragile pattern
  rewriting to translate patterns into this style.

This patch changes the representation to:
* (G_[SZ]EXTLOAD x)
* (G_LOAD x) any-extends when MMO.getSize() * 8 < ResultTy.getSizeInBits()
which resolves these issues by allowing targets to work entirely in their
native register sizes, and by having a more direct translation from
SelectionDAG patterns.

Each extending load can be lowered by the legalizer into separate extends
and loads, however a target that supports s1 will need the any-extending
load to extend to at least s8 since LLVM does not represent memory accesses
smaller than 8 bit. The legalizer can widenScalar G_LOAD into an
any-extending load but sign/zero-extending loads need help from something
else like a combiner pass. A follow-up patch that adds combiner helpers for
for this will follow.

The new representation requires that the MMO correctly reflect the memory
access so this has been corrected in a couple tests. I've also moved the
extending loads to their own tests since they are (mostly) separate opcodes
now. Additionally, the re-write appears to have invalidated two tests from
select-with-no-legality-check.mir since the matcher table no longer contains
loads that result in s1's and they aren't legal in AArch64 anymore.

Depends on D45540

Reviewers: ab, aditya_nandakumar, bogner, rtereshin, volkan, rovka, javed.absar

Reviewed By: rtereshin

Subscribers: javed.absar, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D45541

llvm-svn: 331601
2018-05-05 20:53:24 +00:00
Roman Tereshin beb393126b [GlobalISel][InstructionSelect] Making Coverage Info generation optional on per-match table basis
to make sure that Testgen always has access to coverage info even if
the match table used by the selector itself is stripped off that
information for performance reasons.

Reviewers: dsanders, aemerson

Reviewed By: dsanders

Subscribers: rovka, kristof.beyls, llvm-commits, dsanders

Differential Revision: https://reviews.llvm.org/D46098

llvm-svn: 331398
2018-05-02 20:15:11 +00:00
Roman Tereshin 2d6d3762a0 [GlobalISel][InstructionSelect] Refactoring buildMatchTable out, NFC
to share it between the Instruction Selector in optimized and
non-optimized modes both and the Testgen.

Reviewers: dsanders, aemerson

Reviewed By: dsanders

Subscribers: rovka, kristof.beyls, llvm-commits, dsanders

Differential Revision: https://reviews.llvm.org/D46097

llvm-svn: 331396
2018-05-02 20:08:14 +00:00
Roman Tereshin 2df4c22915 [GlobalISel][InstructionSelect] Refactoring out a getMatchTable virtual method + other small NFC's
The main goal is to share getMatchTable between the Instruction
Selector and the Testgen.

The commit also contains some NFC only loosely related to refactoring
out the getMatchTable, but strongly related to the initial Testgen
patch (see https://reviews.llvm.org/D43962)

Reviewers: dsanders, aemerson

Reviewed By: dsanders

Subscribers: rovka, kristof.beyls, llvm-commits, dsanders

Differential Revision: https://reviews.llvm.org/D46096

llvm-svn: 331395
2018-05-02 20:07:15 +00:00
Mandeep Singh Grang 1b0e2f2a20 [TableGen] Change std::sort to llvm::sort in response to r327219
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.

Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.

Reviewers: stoklund, kparzysz, dsanders

Reviewed By: dsanders

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45144

llvm-svn: 329451
2018-04-06 20:18:05 +00:00
David Blaikie 13e77db2df Fix layering of MachineValueType.h by moving it from CodeGen to Support
This is used by llvm tblgen as well as by LLVM Targets, so the only
common place is Support for now. (maybe we need another target for these
sorts of things - but for now I'm at least making them correct & we can
make them better if/when people have strong feelings)

llvm-svn: 328395
2018-03-23 23:58:25 +00:00
Aditya Nandakumar b63e763847 [GISel]: Make GlobalISelEmitter rule prioritization compatible with selectionDAG
This patch changes GlobalISelEmitter to rank patterns similar to how the
DAG does it (ie it computes a score for a pattern and adds the added
complexity to it).
This is so that the decision tree for GISelSelector remains compatible
with that of SelectionDAG.

https://reviews.llvm.org/D43270

llvm-svn: 325401
2018-02-16 22:37:15 +00:00
Daniel Sanders 08464524c3 [ARM][GISel] PR35965 Constrain RegClasses of nested instructions built from Dst Pattern
Summary:
Apparently, we missed on constraining register classes of VReg-operands of all the instructions
built from a destination pattern but the root (top-level) one. The issue exposed itself
while selecting G_FPTOSI for armv7: the corresponding pattern generates VTOSIZS wrapped
into COPY_TO_REGCLASS, so top-level COPY_TO_REGCLASS gets properly constrained,
while nested VTOSIZS (or rather its destination virtual register to be exact) does not.

Fixing this by issuing GIR_ConstrainSelectedInstOperands for every nested GIR_BuildMI.

https://bugs.llvm.org/show_bug.cgi?id=35965
rdar://problem/36886530

Patch by Roman Tereshin

Reviewers: dsanders, qcolombet, rovka, bogner, aditya_nandakumar, volkan

Reviewed By: dsanders, qcolombet, rovka

Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D42565

llvm-svn: 323692
2018-01-29 21:09:12 +00:00
Volkan Keles 4f3fa79842 [GlobalISel][TableGen] Fix the statistics for emitted patters
Collected statistics for the number of patterns emitted can be
incorrect because rules can be grouped if OptimizeMatchTable
is enabled. Increase the counter in RuleMatcher::emit(...)
to avoid that.

llvm-svn: 323391
2018-01-25 00:18:52 +00:00
Hiroshi Inoue 501931b117 [NFC] fix trivial typos in comments
"the the" -> "the"

llvm-svn: 323302
2018-01-24 05:04:35 +00:00
Daniel Sanders 12e6e709e9 [globalisel][tablegen] Honour priority order within nested instructions.
It appears that we haven't been prioritizing rules that contain nested
instructions properly. InstructionOperandMatcher didn't override
isHigherPriorityThan so it never compared the instructions/operands/predicates
inside nested instructions.

Fixes PR35926. Thanks to Diana Picus for the bug report.

llvm-svn: 322754
2018-01-17 20:34:29 +00:00
Volkan Keles f7f2568613 [GlobalISel][TableGen] Add support for SDNodeXForm
Summary:
This patch adds CustomRenderer which renders the matched
operands to the specified instruction.

Targets can enable the matching of SDNodeXForm by adding
a definition that inherits from GICustomOperandRenderer and
GISDNodeXFormEquiv as follows.

def gi_imm8 : GICustomOperandRenderer<"renderImm8”>,
                       GISDNodeXFormEquiv<imm8_xform>;

Custom renderer functions should be of the form:
void render(MachineInstrBuilder &MIB, const MachineInstr &I);

Reviewers: dsanders, ab, rovka

Reviewed By: dsanders

Subscribers: kristof.beyls, javed.absar, llvm-commits, mgrang, qcolombet

Differential Revision: https://reviews.llvm.org/D42012

llvm-svn: 322582
2018-01-16 18:44:05 +00:00
Aaron Ballman 82e17f58f0 Do not generate an empty switch statement as it causes MSVC to issue diagnostics about switch statements without case or default labels.
llvm-svn: 321217
2017-12-20 20:09:30 +00:00
Daniel Sanders 32de8bbd30 [globalisel][tablegen] Allow ImmLeaf predicates to use InstructionSelector members
NFC for currently supported targets. This resolves a problem encountered by
targets such as RISCV that reference `Subtarget` in ImmLeaf predicates.

llvm-svn: 321176
2017-12-20 14:41:51 +00:00
Quentin Colombet 63a328c30c [TableGen][GlobalISel] Reset the internal map of RuleMatchers just before the emission
Between the creation of the last InstructionMatcher and the first
emission of the related Rule, we need to clear the internal map of IDs.
We used to do that right after the creation of the main
InstructionMatcher when building the rule and although that worked, this
is fragile because if for some reason some later code decides to create
more InstructionMatcher before the final call to emit, then the IDs
would be completely messed up.

Move that to the beginning of "emit" so that the IDs are guarantee to be
consistent.

NFC.

llvm-svn: 321053
2017-12-19 02:57:23 +00:00
Quentin Colombet eba10cbc88 [TableGen][GlobalISel] Make the arguments of the Instruction and Operand Matchers consistent
Move InsnVarID and OpIdx at the beginning of the list of arguments
for all the constructors of the OperandMatcher subclasses.
This matches what we do for the InstructionMatcher.

NFC.

llvm-svn: 321031
2017-12-18 22:12:13 +00:00
Quentin Colombet 34688b9e38 [TableGen][GlobalISel] Refactor optimizeRules related bit to allow code reuse
In theory, reapplying optimizeRules on each group matchers should give
us a second nesting level on the matching table. In practice, we need
more work to make that happen because all the predicates are actually
not directly available through the predicate matchers list.

NFC.

llvm-svn: 321025
2017-12-18 21:25:53 +00:00
Quentin Colombet ec76d9c47f [TableGen][GlobalISel] Optimize MatchTable for faster instruction selection
*** Context ***

Prior to this patchw, the table generated for matching instruction was
straight forward but highly inefficient.

Basically, each pattern generates its own set of self contained checks
and actions.
E.g., TableGen generated:
// First pattern
CheckNumOperand 3
CheckOpcode G_ADD
...
Build ADDrr
// Second pattern
CheckNumOperand 3
CheckOpcode G_ADD
...
Build ADDri
// Third pattern
CheckNumOperand 3
CheckOpcode G_SUB
...
Build SUBrr

*** Problem ***

Because of that generation, a *lot* of check were redundant between each
pattern and were checked every single time until we reach the pattern
that matches.
E.g., Taking the previous table, let say we are matching a G_SUB, that
means we were going to check all the rules for G_ADD before looking at
the G_SUB rule. In particular we are going to do:
check 3 operands; PASS
check G_ADD; FAIL
; Next rule
check 3 operands; PASS (but we already knew that!)
check G_ADD; FAIL (well it is still not true)
; Next rule
check 3 operands; PASS (really!!)
check G_SUB; PASS (at last :P)

*** Proposed Solution ***

This patch introduces a concept of group of rules (GroupMatcher) that
share some predicates and only get checked once for the whole group.

This patch only creates groups with one nesting level. Conceptually
there is nothing preventing us for having deeper nest level. However,
the current implementation is not smart enough to share the recording
(aka capturing) of values. That limits its ability to do more sharing.

For the given example the current patch will generate:
// First group
CheckOpcode G_ADD

 // First pattern
 CheckNumOperand 3
 ...
 Build ADDrr
 // Second pattern
 CheckNumOperand 3
 ...
 Build ADDri

// Second group
CheckOpcode G_SUB

 // Third pattern
 CheckNumOperand 3
 ...
 Build SUBrr

But if we allowed several nesting level, it could create a sub group
for the checknumoperand 3.
(We would need to call optimizeRules on the rules within a group.)

*** Result ***

With only one level of nesting, the instruction selection pass is up
to 4x faster. For instance, one instruction now takes 500 checks,
instead of 24k! With more nesting we could get in the tens I believe.

Differential Revision: https://reviews.llvm.org/D39034

rdar://problem/34670699

llvm-svn: 321017
2017-12-18 19:47:41 +00:00
Quentin Colombet 893e0f15e2 [TableGen][GlobalISel] Make the different Matcher comparable
This opens refactoring opportunities in the match table now that we can
check that two predicates are the same.

NFC.

llvm-svn: 320890
2017-12-15 23:24:39 +00:00
Quentin Colombet a646ef08e8 [TableGen][GlobalISel] Fix unused variable warning in release mode
Introduced in r320887.

NFC.

llvm-svn: 320889
2017-12-15 23:24:36 +00:00
Quentin Colombet aad20be6ca [TableGen][GlobalISel] Have the predicate directly know which data they are dealing with
Prior to this patch, a predicate wouldn't make sense outside of its
rule. Indeed, it was only during emitting a rule that a predicate would
be made aware of the IDs of the data it is checking. Because of that,
predicates could not be moved around or compared between each other.

NFC.

llvm-svn: 320887
2017-12-15 23:07:42 +00:00
Quentin Colombet 063d798acb [TableGen][GlobalISel] Add a common class for all PredicateMatcher
NFC.

llvm-svn: 320767
2017-12-14 23:44:07 +00:00
Daniel Sanders 3c1c4c0ee0 Revert r319691: [globalisel][tablegen] Split atomic load/store into separate opcode and enable for AArch64.
Some concerns were raised with the direction. Revert while we discuss it and look into an alternative

llvm-svn: 319739
2017-12-05 05:52:07 +00:00
Daniel Sanders 04e4f47e93 [globalisel][tablegen] Split atomic load/store into separate opcode and enable for AArch64.
This patch splits atomics out of the generic G_LOAD/G_STORE and into their own
G_ATOMIC_LOAD/G_ATOMIC_STORE. This is a pragmatic decision rather than a
necessary one. Atomic load/store has little in implementation in common with
non-atomic load/store. They tend to be handled very differently throughout the
backend. It also has the nice side-effect of slightly improving the common-case
performance at ISel since there's no longer a need for an atomicity check in the
matcher table.

All targets have been updated to remove the atomic load/store check from the
G_LOAD/G_STORE path. AArch64 has also been updated to mark
G_ATOMIC_LOAD/G_ATOMIC_STORE legal.

There is one issue with this patch though which also affects the extending loads
and truncating stores. The rules only match when an appropriate G_ANYEXT is
present in the MIR. For example,
  (G_ATOMIC_STORE (G_TRUNC:s16 (G_ANYEXT:s32 (G_ATOMIC_LOAD:s16 X))))
will match but:
  (G_ATOMIC_STORE (G_ATOMIC_LOAD:s16 X))
will not. This shouldn't be a problem at the moment, but as we get better at
eliminating extends/truncates we'll likely start failing to match in some
cases. The current plan is to fix this in a patch that changes the
representation of extending-load/truncating-store to allow the MMO to describe
a different type to the operation.

llvm-svn: 319691
2017-12-04 20:39:32 +00:00
Daniel Sanders 0c43b3a023 [globalisel][tablegen] Add support for relative AtomicOrderings
No test yet because the relevant rules are blocked on the atomic_load,
and atomic_store nodes.

llvm-svn: 319475
2017-11-30 21:05:59 +00:00
Daniel Sanders f499b2bf1f [globalisel][tablegen] Add support for specific immediates in the match pattern
This enables a few rules such as ARM's uxtb instruction.

llvm-svn: 319457
2017-11-30 18:48:35 +00:00
Daniel Sanders 766646517f [globalisel][tablegen] Add support for importing G_ATOMIC_CMPXCHG, G_ATOMICRMW_* rules from SelectionDAG.
GIM_CheckNonAtomic has been replaced by GIM_CheckAtomicOrdering to allow it to support a wider
range of orderings. This has then been used to import patterns using nodes such
as atomic_cmp_swap, atomic_swap, and atomic_load_*.

llvm-svn: 319232
2017-11-28 22:07:05 +00:00
Daniel Sanders c54aa9c844 [globalisel][tablegen] Generalize pointer-type inference by introducing ptypeN. NFC
ptypeN is functionally the same as typeN except that it informs the
SelectionDAG importer that an operand should be treated as a pointer even
if it was written as iN. This is important for patterns that use iN instead
of iPTR to represent pointers. E.g.:
  (set GPR64:$dst, (load GPR64:$addr))

Previously, this was handled as a hardcoded special case for the appropriate
operands to G_LOAD and G_STORE.

llvm-svn: 318574
2017-11-18 00:16:44 +00:00
Daniel Sanders f76f315436 [globalisel][tablegen] Generate rule coverage and use it to identify untested rules
Summary:
This patch adds a LLVM_ENABLE_GISEL_COV which, like LLVM_ENABLE_DAGISEL_COV,
causes TableGen to instrument the generated table to collect rule coverage
information. However, LLVM_ENABLE_GISEL_COV goes a bit further than
LLVM_ENABLE_DAGISEL_COV. The information is written to files
(${CMAKE_BINARY_DIR}/gisel-coverage-* by default). These files can then be
concatenated into ${LLVM_GISEL_COV_PREFIX}-all after which TableGen will
read this information and use it to emit warnings about untested rules.

This technique could also be used by SelectionDAG and can be further
extended to detect hot rules and give them priority over colder rules.

Usage:
* Enable LLVM_ENABLE_GISEL_COV in CMake
* Build the compiler and run some tests
* cat gisel-coverage-[0-9]* > gisel-coverage-all
* Delete lib/Target/*/*GenGlobalISel.inc*
* Build the compiler

Known issues:
* ${LLVM_GISEL_COV_PREFIX}-all must be generated as a manual
  step due to a lack of a portable 'cat' command. It should be the
  concatenation of all ${LLVM_GISEL_COV_PREFIX}-[0-9]* files.
* There's no mechanism to discard coverage information when the ruleset
  changes

Depends on D39742

Reviewers: ab, qcolombet, t.p.northover, aditya_nandakumar, rovka

Reviewed By: rovka

Subscribers: vsk, arsenm, nhaehnle, mgorny, kristof.beyls, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D39747

llvm-svn: 318356
2017-11-16 00:46:35 +00:00
Daniel Sanders b78ac6e322 [globalisel][tablegen] Add support for extload.
llvm-svn: 318068
2017-11-13 18:30:23 +00:00
Daniel Sanders 7e52367398 [globalisel][tablegen] Import signextload and zeroextload.
Allow a pattern rewriter to be installed in CodeGenDAGPatterns and use it to
correct situations where SelectionDAG and GlobalISel disagree on
representation. For example, it would rewrite:
  (sextload:i32 $ptr)<<unindexedload>><<sextload>><<sextloadi16>
to:
  (sext:i32 (load:i16 $ptr)<<unindexedload>>)

I'd have preferred to replace the fragments and have the expansion happen
naturally as part of PatFrag expansion but the type inferencing system can't
cope with loads of types narrower than those mentioned in register classes.
This is because the SDTCisInt's on the sext constrain both the result and
operand to the 'legal' integer types (where legal is defined as 'a register
class can contain the type') which immediately rules the narrower types out.
Several targets (those with only one legal integer type) would then go on to
crash on the SDTCisOpSmallerThanOp<> when it removes all the possible types
for the result of the extend.

Also, improve isObviouslySafeToFold() slightly to automatically return true for
neighbouring instructions. There can't be any re-ordering problems if
re-ordering isn't happenning. We'll need to improve it further to handle
sign/zero-extending loads when the extend and load aren't immediate neighbours
though.

llvm-svn: 317971
2017-11-11 03:23:44 +00:00
Diana Picus d1b618177a [globalisel][tablegen] Skip src child predicates
The GlobalISel TableGen backend didn't check for predicates on the
source children. This caused it to generate code for ARM patterns such
as SMLABB or similar, but without properly checking for the sext_16_node
part of the operands. This in turn meant that we would select SMLABB
instead of MLA for simple sequences such as s32 + s32 * s32, which is
wrong (we want a MLA on the full operands, not just their bottom 16
bits).

This patch forces TableGen to skip patterns with predicates on the src
children, so it doesn't generate code for SMLABB and other similar ARM
instructions at all anymore. AArch64 and X86 are not affected.

Differential Revision: https://reviews.llvm.org/D39554

llvm-svn: 317313
2017-11-03 10:30:19 +00:00
Daniel Sanders 9cbe7c7f93 [globalisel][tablegen] Add support for multi-insn emission
The importer will now accept nested instructions in the result pattern such as
(ADDWrr $a, (SUBWrr $b, $c)). This is only valid when the nested instruction
def's a single vreg and the parent instruction consumes a single vreg where a
nested instruction is specified. The importer will automatically create a vreg
to connect the two using the type information from the pattern. This vreg will
be constrained to the register classes given in the instruction definitions*.

* REG_SEQUENCE is explicitly rejected because of this. The definition doesn't
  constrain to a register class and it therefore needs special handling.

llvm-svn: 317117
2017-11-01 19:57:57 +00:00
Daniel Sanders 198447a447 [globalisel][tablegen] Stop hard-coding the emitted instruction ID to 0. NFC
The next commit will add support for multi-instruction emission so we need to
start allocating instruction ID's instead of hard-coding them to 0.

llvm-svn: 317057
2017-11-01 00:29:47 +00:00
Daniel Sanders 7438b26317 Re-commit: [globalisel][tablegen] Keep track of the insertion point while adding BuildMIAction's. NFC
Multi-instruction emission needs to ensure the the instructions are generated
a depth-first fashion. For example:
(ADDWrr (SUBWrr a, b), c)
needs to emit the SUBWrr before the ADDWrr. However, our walk over
TreePatternNode's is highly context sensitive which makes it difficult to append
BuildMIActions in the order we want. To fix this, we now keep track of the
insertion point as we add actions. This will allow multi-insn emission to insert
BuildMI's in the correct place.

The previous commit failed on the Ubuntu bots using GCC 4.8. These bots lack the
const_iterator forms of insert() and emplace() that were added in C++11. As a
result I've switched the const_iterators to iterators.

llvm-svn: 317049
2017-10-31 23:03:18 +00:00
Daniel Sanders f69d1b018c Revert r317040: [globalisel][tablegen] Keep track of the insertion point while adding BuildMIAction's. NFC
The same bots fail but I believe I know what the issue is now. These bots are
missing the const_iterator versions of insert/emplace/etc. that were introduced
in C++11.

llvm-svn: 317042
2017-10-31 21:54:52 +00:00
Daniel Sanders 374f71ac90 Re-commit: [globalisel][tablegen] Keep track of the insertion point while adding BuildMIAction's. NFC
Multi-instruction emission needs to ensure the the instructions are generated
a depth-first fashion. For example:
 (ADDWrr (SUBWrr a, b), c)
needs to emit the SUBWrr before the ADDWrr. However, our walk over
TreePatternNode's is highly context sensitive which makes it difficult to append
BuildMIActions in the order we want. To fix this, we now keep track of the
insertion point as we add actions. This will allow multi-insn emission to insert
BuildMI's in the correct place.

The previous commit failed on the Ubuntu bots using GCC 4.8. These bots didn't
like a call to emplace(). I've replaced it with insert() to see if it's a quirk
of the C++11 support.

llvm-svn: 317040
2017-10-31 21:34:53 +00:00
Daniel Sanders f87c142d9e Revert r317029: [globalisel][tablegen] Keep track of the insertion point while adding BuildMIAction's. NFC
The Linux bots don't seem to like this usage of emplace(). Reverting while I look into it.

llvm-svn: 317033
2017-10-31 20:29:28 +00:00
Daniel Sanders e8a4f0d869 [globalisel][tablegen] Keep track of the insertion point while adding BuildMIAction's. NFC
Multi-instruction emission needs to ensure the the instructions are generated
a depth-first fashion. For example:
  (ADDWrr (SUBWrr a, b), c)
needs to emit the SUBWrr before the ADDWrr. However, our walk over
TreePatternNode's is highly context sensitive which makes it difficult to append
BuildMIActions in the order we want. To fix this, we now keep track of the
insertion point as we add actions. This will allow multi-insn emission to insert
BuildMI's in the correct place.

llvm-svn: 317029
2017-10-31 19:54:05 +00:00
Daniel Sanders df258e328a [globalisel][tablegen] Factor out implicit def/use renderers from createAndImportInstructionRenderer(). NFC
Multi-instruction emission will require that we have separate handling for
the defs between the implicitly created temporaries and the rule outputs.
The former require new temporary vregs while the latter should copy existing
operands. Factor out the implicit def/use renderers to minimize the code
duplication when we implement that.

llvm-svn: 317025
2017-10-31 19:09:29 +00:00
Daniel Sanders a7b7526416 [globalisel][tablegen] Add infrastructure to potentially allow BuildMIAction to choose a mutatable instruction. NFC
Prepare for multiple instruction emission by allowing BuildMIAction to
search for a suitable matcher that will support mutation.

This patch deliberately neglects to add matchers aside from the root to
preserve NFC. That said, it should be noted that until we support mutations
other than just the opcode the chances of finding a non-root instruction
for which canMutate() is true, is essentially zero. Furthermore in the
presence of multi-instruction emission the chances of finding any
instruction for which canMutate() is true is also zero. Nevertheless, we
can't continue to require that all BuildMIAction's consider the root of the match
to be recyclable due to the risk of recycling it twice in the same rule.

llvm-svn: 317022
2017-10-31 18:50:24 +00:00
Daniel Sanders 6ea17edd80 [globalisel][tablegen] Allow any comment in DebugCommentAction. NFC
llvm-svn: 317017
2017-10-31 18:07:03 +00:00
Daniel Sanders ab1d119154 [globalisel][tablegen] Fix future undefined behaviour in r316463.
I missed a dereference of `Matched` that preceeded the new check. Thanks to
Justin Bogner for spotting it.

llvm-svn: 316480
2017-10-24 18:11:54 +00:00
Daniel Sanders 64f745cf20 [globalisel][tablegen] Multi-insn emission requires that BuildMIAction support not being linked to an InstructionMatcher. NFC
When multi-instruction emission is supported, it will no longer be guaranteed
that every BuildMIAction has a corresponding matched instruction. BuildMIAction
should support not having one to cover the case where a rule produces more
instructions than it matched.

llvm-svn: 316463
2017-10-24 17:08:43 +00:00
Daniel Sanders bd83ad4a87 [globalisel][tablegen] Remove unused InstructionMatcher's. NFC
llvm-svn: 316407
2017-10-24 01:48:34 +00:00
Daniel Sanders d66e0901ae [globalisel][tablegen] Import stores and allow GISel to automatically substitute zero regs like WZR/XZR/$zero.
This patch enables the import of stores. Unfortunately, doing so by itself,
loses an optimization where storing 0 to memory makes use of WZR/XZR.

To mitigate this, this patch also introduces a new feature that allows register
operands to nominate a zero register. When this is done, GlobalISel will
substitute (G_CONSTANT 0) with the nominated register automatically. This
is currently configured to only apply to the stores.

Applying it to GPR32/GPR64 register classes in general will be done after
review see (https://reviews.llvm.org/D39150).

llvm-svn: 316360
2017-10-23 18:19:24 +00:00
Daniel Sanders 1e4569fdc1 [globalisel][tablegen] Fix small spelling nits. NFC
ComplexRendererFn -> ComplexRendererFns
Corrected a couple lingering references to tied operands that were missed.

llvm-svn: 316237
2017-10-20 20:55:29 +00:00
Reid Kleckner cfdd4a2699 Revert MSVC 2017 build fix and fix it by moving the method that implicitly instantiates addPredicate out of line
llvm-svn: 315932
2017-10-16 20:31:16 +00:00
Reid Kleckner 46e0918f83 Fix the build of GlobalISelEmitter with MSVC 2017 by specializing earlier
MSVC doesn't seem to like implicitly instantiating addPredicate and then
explicitly specializing it later. It causes an internal compiler error.

llvm-svn: 315930
2017-10-16 20:23:16 +00:00
Daniel Sanders ea8711b88e Re-commit r315885: [globalisel][tblgen] Add support for iPTR and implement am_unscaled* and am_indexed*
Summary:
iPTR is a pointer of subtarget-specific size to any address space. Therefore
type checks on this size derive the SizeInBits from a subtarget hook.

At this point, we can import the simplests G_LOAD rules and select load
instructions using them. Further patches will support for the predicates to
enable additional loads as well as the stores.

The previous commit failed on MSVC due to a failure to convert an
initializer_list to a std::vector. Hopefully, MSVC will accept this version.

Depends on D37457

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: kristof.beyls, javed.absar, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37458

llvm-svn: 315887
2017-10-16 03:36:29 +00:00
Daniel Sanders ce72d611af Revert r315885: [globalisel][tblgen] Add support for iPTR and implement am_unscaled* and am_indexed*
MSVC doesn't like one of the constructors.

llvm-svn: 315886
2017-10-16 02:15:39 +00:00
Daniel Sanders 6735ea86cd [globalisel][tblgen] Add support for iPTR and implement am_unscaled* and am_indexed*
Summary:
iPTR is a pointer of subtarget-specific size to any address space. Therefore
type checks on this size derive the SizeInBits from a subtarget hook.

At this point, we can import the simplests G_LOAD rules and select load
instructions using them. Further patches will support for the predicates to
enable additional loads as well as the stores.

Depends on D37457

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: kristof.beyls, javed.absar, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37458

llvm-svn: 315885
2017-10-16 01:16:35 +00:00
Daniel Sanders a71f454765 [globalisel][tablegen] Implement unindexed load, non-extending load, and MemVT checks
Summary:
This includes some context-sensitivity in the MVT to LLT conversion so that
pointer types are tested correctly.
FIXME: I'm not happy with the way this is done since everything is a
       special-case. I've yet to find a reasonable way to implement it.

select-load.mir fails because <1 x s64> loads in tablegen get priority over s64
loads. This is fixed in the next patch and as such they should be committed
together, I've posted them separately to help with the review.

Depends on D37456

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Subscribers: kristof.beyls, javed.absar, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37457

llvm-svn: 315884
2017-10-16 00:56:30 +00:00
Daniel Sanders df39cbae2f Re-commit r315863: [globalisel][tablegen] Import ComplexPattern when used as an operator
Summary:
It's possible for a ComplexPattern to be used as an operator in a match
pattern. This is used by the load/store patterns in AArch64 to name the
suboperands returned by ComplexPattern predicate so that they can be broken
apart and referenced independently in the result pattern.

This patch adds support for this in order to enable the import of load/store
patterns.

Depends on D37445

Hopefully fixed the ambiguous constructor that a large number of bots reported.

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: aemerson, javed.absar, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D37456

llvm-svn: 315869
2017-10-15 18:22:54 +00:00
Daniel Sanders bb082a36d3 Revert r315863: [globalisel][tablegen] Import ComplexPattern when used as an operator
A large number of bots are failing on an ambiguous constructor call.

llvm-svn: 315866
2017-10-15 17:51:07 +00:00
Daniel Sanders b95b867dd8 [globalisel][tablegen] Import ComplexPattern when used as an operator
Summary:
It's possible for a ComplexPattern to be used as an operator in a match
pattern. This is used by the load/store patterns in AArch64 to name the
suboperands returned by ComplexPattern predicate so that they can be broken
apart and referenced independently in the result pattern.

This patch adds support for this in order to enable the import of load/store
patterns.

Depends on D37445

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: aemerson, javed.absar, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D37456

llvm-svn: 315863
2017-10-15 17:03:36 +00:00
Daniel Sanders 39690bdf42 [globalisel][tablegen] Map ld and st to G_LOAD and G_STORE. NFC
Summary:
There is an important mismatch between ISD::LOAD and G_LOAD (and likewise for
ISD::STORE and G_STORE). In SelectionDAG, ISD::LOAD is a non-atomic load
and atomic loads are handled by a separate node. However, this is not true of
GlobalISel's G_LOAD. For G_LOAD, the MachineMemOperand indicates the atomicity
of the operation. As a result, this mapping must also add a predicate that
checks for non-atomic MachineMemOperands.

This is NFC since these nodes always have predicates in practice and are
therefore always rejected at the moment.

Depends on D37443

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: kristof.beyls, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37445

llvm-svn: 315843
2017-10-15 02:41:12 +00:00
Daniel Sanders 3f267bf769 [tablegen] Handle common load/store predicates inside tablegen. NFC.
Summary:
GlobalISel and SelectionDAG require different code for the common
load/store predicates due to differences in the representation.
For example:
   SelectionDAG: (load<signext,i8>:i32 GPR32:$addr) // The <> denote properties of the SDNode that are not printed in the DAG
   GlobalISel: (G_SEXT:s32 (G_LOAD:s8 GPR32:$addr))
Even without that, differences in the IR (SDNode vs MachineInstr) require
differences in the C++ predicate.

This patch moves the implementation of the common load/store predicates
into tablegen so that it can handle these differences.

It's NFC for SelectionDAG since it emits equivalent code and it's NFC for
GlobalISel since the rules involving the relevant predicates are still
rejected by the importer.

Depends on D36618

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Subscribers: llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D37443

Includes a partial revert of r315826 since this patch makes it necessary for
getPredCode() to return a std::string and getImmCode() should have the same
interface as getPredCode().

llvm-svn: 315841
2017-10-15 02:06:44 +00:00
Simon Pilgrim 6ecae9fc97 [TableGen] Avoid unnecessary std::string creations
Avoid unnecessary std::string creations in the TreePredicateFn getters.

llvm-svn: 315826
2017-10-14 21:27:53 +00:00
Daniel Sanders bfa9e2cae7 [globalisel][tablegen] Simplify named operand/operator lookups and fix a wrong-code bug this revealed.
Summary:
Operand variable lookups are now performed by the RuleMatcher rather than
searching the whole matcher hierarchy for a match. This revealed a wrong-code
bug that currently affects ARM and X86 where patterns that use a variable more
than once in the match pattern will be imported but won't check that the
operands are identical. This can cause the tablegen-erated matcher to
accept matches that should be rejected.

Depends on D36569

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Subscribers: aemerson, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D36618

llvm-svn: 315780
2017-10-14 00:31:58 +00:00
Daniel Sanders 2fed4ffa9e [globalisel][tablegen] Fix a use-after free bug that manifests on non-macOS machines.
llvm-svn: 315765
2017-10-13 21:51:20 +00:00
Daniel Sanders 11300cead8 [globalisel][tablegen] Add support for fpimm and import of APInt/APFloat based ImmLeaf.
Summary:
There's only a tablegen testcase for IntImmLeaf and not a CodeGen one
because the relevant rules are rejected for other reasons at the moment.
On AArch64, it's because there's an SDNodeXForm attached to the operand.
On X86, it's because the rule either emits multiple instructions or has
another predicate using PatFrag which cannot easily be supported at the
same time.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: aemerson, javed.absar, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D36569

llvm-svn: 315761
2017-10-13 21:28:03 +00:00
Daniel Sanders 649c585710 [aarch64] Support APInt and APFloat in ImmLeaf subclasses and make AArch64 use them.
Summary:
The purpose of this patch is to expose more information about ImmLeaf-like
PatLeaf's so that GlobalISel can learn to import them. Previously, ImmLeaf
could only be used to test int64_t's produced by sign-extending an APInt.
Other tests on immediates had to use the generic PatLeaf and extract the
constant using C++.

With this patch, tablegen will know how to generate predicates for APInt,
and APFloat. This will allow it to 'do the right thing' for both SelectionDAG
and GlobalISel which require different methods of extracting the immediate
from the IR.

This is NFC for SelectionDAG since the new code is equivalent to the
previous code. It's also NFC for FastISel because FastIselShouldIgnore is 1
for the ImmLeaf subclasses. Enabling FastIselShouldIgnore == 0 for these new
subclasses will require a significant re-factor of FastISel.

For GlobalISel, it's currently NFC because the relevant code to import the
affected rules is not yet present. This will be added in a later patch.

Depends on D36086

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: bjope, aemerson, rengolin, javed.absar, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D36534

llvm-svn: 315747
2017-10-13 20:42:18 +00:00
Daniel Sanders 4d4e7650dc [globalisel] Add support for ValueType operands in patterns.
It's rare but there are a small number of patterns like this:
    (set i64:$dst, (add i64:$src1, i64:$src2))
These should be equivalent to register classes except they shouldn't check for
a specific register bank.

This doesn't occur in AArch64/ARM/X86 but does occasionally come up in other
in-tree targets such as BPF.

llvm-svn: 315226
2017-10-09 18:14:53 +00:00
Daniel Sanders 28887fe548 [globalisel] Add support for intrinsic_w_chain.
This maps directly to G_INTRINSIC_W_SIDE_EFFECTS.

llvm-svn: 313627
2017-09-19 12:56:36 +00:00
Krzysztof Parzyszek 779d98e1c0 TableGen support for parameterized register class information
This replaces TableGen's type inference to operate on parameterized
types instead of MVTs, and as a consequence, some interfaces have
changed:
- Uses of MVTs are replaced by ValueTypeByHwMode.
- EEVT::TypeSet is replaced by TypeSetByHwMode.

This affects the way that types and type sets are printed, and the
tests relying on that have been updated.

There are certain users of the inferred types outside of TableGen
itself, namely FastISel and GlobalISel. For those users, the way
that the types are accessed have changed. For typical scenarios,
these replacements can be used:
- TreePatternNode::getType(ResNo) -> getSimpleType(ResNo)
- TreePatternNode::hasTypeSet(ResNo) -> hasConcreteType(ResNo)
- TypeSet::isConcrete -> TypeSetByHwMode::isValueTypeByHwMode(false)

For more information, please refer to the review page.

Differential Revision: https://reviews.llvm.org/D31951

llvm-svn: 313271
2017-09-14 16:56:21 +00:00
Daniel Sanders 069bb8d45f [globalisel][tablegen] Predicates should start from GIPFP_Invalid+1 not GIPFP_Invalid
This fixes a warning when there are zero defined predicates and also fixes an
unnoticed bug where the first predicate in the table was unusable.

llvm-svn: 311684
2017-08-24 18:54:16 +00:00
Daniel Sanders 2c269f6bf8 Re-commit: [globalisel][tablegen] Add support for ImmLeaf without SDNodeXForm
Summary:
This patch adds support for predicates on imm nodes but only for ImmLeaf and not
for PatLeaf or PatFrag and only where the value does not need to be transformed
before being rendered into the instruction.

The limitation on PatLeaf/PatFrag/SDNodeXForm is due to differences in the
necessary target-supplied C++ for GlobalISel.

Depends on D36085

The previous commit was reverted for breaking the build but this appears to have
been the recurring problem on the Windows bots with tablegen not being re-run
when llvm-tblgen is changed but the .td's aren't. If it re-occurs then forcing a
build with clean=True should fix it but this string should do this in advance:
    Requires a clean build.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36086

llvm-svn: 311645
2017-08-24 09:11:20 +00:00
Victor Leschuk 3697ebe25f Revert r311546 as it breaks build
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/4394

llvm-svn: 311560
2017-08-23 15:21:10 +00:00
Daniel Sanders c3885c4589 [globalisel][tablegen] Add support for ImmLeaf without SDNodeXForm
Summary:
This patch adds support for predicates on imm nodes but only for ImmLeaf and not for PatLeaf or PatFrag and only where the value does not need to be transformed before being rendered into the instruction.

The limitation on PatLeaf/PatFrag/SDNodeXForm is due to differences in the necessary target-supplied C++ for GlobalISel.

Depends on D36085

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36086

llvm-svn: 311546
2017-08-23 12:14:18 +00:00
Daniel Sanders 499807079b [globalisel][tablegen] Add tests for FeatureBitsets and ComplexPattern predicates.
llvm-svn: 311542
2017-08-23 10:09:25 +00:00
Daniel Sanders 032e7f2cad [globalisel][tablegen] Generate TypeObject table. NFC
Summary:
Generate the type table from the types used by a target rather than hard-coding
the union of types used by all targets.

Depends on D36084

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36085

llvm-svn: 311084
2017-08-17 13:18:35 +00:00
Daniel Sanders edd0784be6 Re-commit: [globalisel][tablegen] Support zero-instruction emission.
Summary:
Support the case where an operand of a pattern is also the whole of the
result pattern. In this case the original result and all its uses must be
replaced by the operand. However, register class restrictions can require
a COPY. This patch handles both cases by always emitting the copy and
leaving it for the register allocator to optimize.

The previous commit failed on Windows machines due to a flaw in the sort
predicate which allowed both A < B < C and B == C to be satisfied
simultaneously. The cause of this was some sloppiness in the priority order of
G_CONSTANT instructions compared to other instructions. These had equal priority
because it makes no difference, however there were operands had higher priority
than G_CONSTANT but lower priority than any other instruction. As a result, a
priority order between G_CONSTANT and other instructions must be enforced to
ensure the predicate defines a strict weak order.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Subscribers: javed.absar, kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36084

llvm-svn: 311076
2017-08-17 09:26:14 +00:00
Daniel Sanders eb2f5f3256 Revert r310919 - [globalisel][tablegen] Support zero-instruction emission.
As expected, this failed on the windows bots but the instrumentation showed
something interesting. The ADD8ri and INC8r rules are never directly compared
on the windows machines. That implies that the issue lies in transitivity of
the Compare predicate. I believe I've already verified that but maybe I missed
something.

llvm-svn: 310922
2017-08-15 15:10:31 +00:00
Daniel Sanders 16e6dd3cd6 Re-commit with some instrumentation: [globalisel][tablegen] Support zero-instruction emission.
Summary:
Support the case where an operand of a pattern is also the whole of the
result pattern. In this case the original result and all its uses must be
replaced by the operand. However, register class restrictions can require
a COPY. This patch handles both cases by always emitting the copy and
leaving it for the register allocator to optimize.

The previous commit failed on the windows bots and this one is likely to fail
on those same bots. However, the added instrumentation should reveal a particular
isHigherPriorityThan() evaluation which I'm expecting to expose that
these machines are weighing priority of two rules differently from the
non-windows machines.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Subscribers: javed.absar, kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36084

llvm-svn: 310919
2017-08-15 13:50:09 +00:00
Daniel Sanders e6c216ed5b Revert r310716 (and r310735): [globalisel][tablegen] Support zero-instruction emission.
Two of the Windows bots are failing test\CodeGen\X86\GlobalISel\select-inc.mir
which should not have been affected by the change. Reverting while I investigate.

Also reverted r310735 because it builds on r310716.

llvm-svn: 310745
2017-08-11 19:19:21 +00:00
Daniel Sanders 6ac981151e [globalisel][tablegen] Generate TypeObject table. NFC
Summary:
Generate the type table from the types used by a target rather than hard-coding
the union of types used by all targets.

Depends on D36084

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36085

llvm-svn: 310735
2017-08-11 17:30:37 +00:00
Daniel Sanders 1fb1ce0c87 [globalisel][tablegen] Support zero-instruction emission.
Summary:
Support the case where an operand of a pattern is also the whole of the
result pattern. In this case the original result and all its uses must be
replaced by the operand. However, register class restrictions can require
a COPY. This patch handles both cases by always emitting the copy and
leaving it for the register allocator to optimize.

Depends on D35833

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Subscribers: javed.absar, kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36084

llvm-svn: 310716
2017-08-11 15:40:32 +00:00
Daniel Sanders 75b84fc5ce [globalisel][tablegen] Remove unnecessary ; to satisfy ubuntu-gcc7.1-werror.
llvm-svn: 310357
2017-08-08 13:21:26 +00:00
Daniel Sanders 0554004698 [globalisel][tablegen] Add support for importing 'imm' operands.
Summary:
This patch enables the import of rules containing 'imm' operands that do not
constrain the acceptable values using predicates. Support for ImmLeaf will
arrive in a later patch.

Depends on D35681

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D35833

llvm-svn: 310343
2017-08-08 10:44:31 +00:00
Florian Hahn 3bc3ec661c [GlobalISel] Only merge memory ops for mayLoad or mayStore instrs.
Summary:
We only need to merge memory operands for instructions that access
 memory. This slightly reduces the number of actions executed. 

Reviewers: MatzeB, rovka, dsanders

Reviewed By: dsanders

Subscribers: aemerson, igorb, kristof.beyls, llvm-commits

Differential Revision: https://reviews.llvm.org/D36151

llvm-svn: 309944
2017-08-03 14:48:22 +00:00
Daniel Sanders 078572b6b1 [globalisel][tablegen] Do not merge memoperands from instructions that weren't in the match.
Summary:
Fix a bug discovered in an out-of-tree target where memoperands from
pseudo-instructions that weren't part of the match were being merged into the
result instructions as part of GIR_MergeMemOperands.

This bug was caused by a change to the handling of State.MIs between rules when
the state machine tables were fused into a single table. Previously, each rule
would reset State.MIs using State.MIs.resize(1) but this is no longer done, as a
result stale data is occasionally left in some elements of State.MIs. Most
opcodes aren't affected by this but GIR_MergeMemOperands merges all memoperands
from the intructions recorded in State.MIs into the result instruction.

Suppose for example, we processed but rejected the following pattern:
  (signextend (load x))
at this point, State.MIs contains the signextend and the load. Now suppose we
process and accept this pattern:
  (add x, y)
at this point, State.MIs contains the add as well as the (now irrelevant) load.
When GIR_MergeMemOperands is processed, the memoperands from that irrelevant
load will be merged into the result instruction even though it was not part of
the match.

Bringing back the State.MIs.resize(1) would fix the problem but it would limit
our ability to optimize the table in the future. Instead, this patch fixes the
problem by explicitly stating which instructions should be merged into the result.

There's no direct test case in this commit because a test case would be very brittle.
However, at the time of writing this should fix the failures in
http://green.lab.llvm.org/green/job/Compiler_Verifiers_GlobalISEL/ as well as a
failure in test/CodeGen/ARM/GlobalISel/arm-isel.ll when expensive checks are enabled.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Subscribers: fhahn, kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D36094

llvm-svn: 309804
2017-08-02 11:03:36 +00:00
Daniel Sanders cbbbfe4033 [globalisel][tablegen] Ensure MatchTable's are compile-time constants with constexpr. NFC.
This should prevent any re-occurence of the problem where the table was
initialized at run-time.

llvm-svn: 309267
2017-07-27 12:47:31 +00:00
Daniel Sanders 8e82af2be6 Re-commit: r309094 [globalisel][tablegen] Fuse the generated tables together.
Summary:
Now that we have control flow in place, fuse the per-rule tables into a
single table. This is a compile-time saving at this point. However, this will
also enable the optimization of a table so that similar instructions can be
tested together, reducing the time spent on the matching the code.

This is NFC in terms of externally visible behaviour but some internals have
changed slightly. State.MIs is no longer reset between each rule that is
attempted because it's not necessary to do so. As a consequence of this the
restriction on the order that instructions are added to State.MIs has been
relaxed to only affect recorded instructions that require new elements to be
added to the vector. GIM_RecordInsn can now write to any element from 1 to
State.MIs.size() instead of just State.MIs.size().

The compile-time regressions from the last commit were caused by the ARM target
including a non-const variable (zero_reg) in the table and therefore generating
an initializer for it. That variable is now const.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D35681

llvm-svn: 309264
2017-07-27 11:03:45 +00:00
Daniel Sanders d3077a94a8 Revert r309094: [globalisel][tablegen] Fuse the generated tables together.
The ARM bots have started failing and while this patch should be an improvement
for these bots, it's also the only suspect in the blamelist. Reverting while
Diana and I investigate the problem.

llvm-svn: 309111
2017-07-26 13:28:40 +00:00
Daniel Sanders d83817ad6e [globalisel][tablegen] Fuse the generated tables together.
Summary:
Now that we have control flow in place, fuse the per-rule tables into a
single table. This is a compile-time saving at this point. However, this will
also enable the optimization of a table so that similar instructions can be
tested together, reducing the time spent on the matching the code.

This is NFC in terms of externally visible behaviour but some internals have
changed slightly. State.MIs is no longer reset between each rule that is
attempted because it's not necessary to do so. As a consequence of this the
restriction on the order that instructions are added to State.MIs has been
relaxed to only affect recorded instructions that require new elements to be
added to the vector. GIM_RecordInsn can now write to any element from 1 to
State.MIs.size() instead of just State.MIs.size().

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D35681

llvm-svn: 309094
2017-07-26 10:20:56 +00:00
Daniel Sanders 7aac7cc57f [globalisel][tablegen] Add control-flow to the MatchTable.
Summary:
This will allow us to merge the various sub-tables into a single table. This is a
compile-time saving at this point. However, this will also enable the optimization
of a table so that similar instructions can be tested together, reducing the time
spent on the matching the code.

The bulk of this patch is a mechanical conversion to the new MatchTable object
which is responsible for tracking label definitions and filling in the index of
the jump targets. It is also responsible for nicely formatting the table.

This was necessary to support the new GIM_Try opcode which takes the index to
jump to if the match should fail. This value is unknown during table
construction and is filled in during emission. To support nesting try-blocks
(although we currently don't emit tables with nested try-blocks), GIM_Reject
has been re-introduced to explicitly exit a try-block or fail the overall match
if there are no active try-blocks.

Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D35117

llvm-svn: 308596
2017-07-20 09:25:44 +00:00
Daniel Sanders 57938df813 [globalisel][tablegen] Fix an multi-insn match bug where ComplexPattern is used on multiple insns.
In each rule, each use of ComplexPattern is assigned an element in the Renderers
array. The matcher then collects renderer functions in this array and they are
used to render instructions. This works well for a single instruction but a
bug in the allocation mechanism causes the elements to be assigned on a
per-instruction basis rather than a per-rule basis.

So in the case of:
  (set GPR32:$dst, (Op complex:$src1, complex:$src2))
tablegen currently assigns elements 0 and 1 to $src1 and $src2 respectively,
but for:
  (set GPR32:$dst, (Op complex:$src1, (Op complex:$src2)))
it currently assigned both $src1 and $src2 the same element (0). This results in
one complex operand being rendered twice and the other being forgotten.
This patch corrects the allocation such that $src1 and $src2 are still allocated
different elements in this case.

llvm-svn: 307646
2017-07-11 10:40:18 +00:00
Daniel Sanders fe12c0fa56 [globalisel][tablegen] Correct matching of intrinsic ID's.
TreePatternNode considers them to be plain integers but MachineInstr considers
them to be a distinct kind of operand.

The tweak to AArch64InstrInfo.td to produce a simple test case is a NFC for
everything except GlobalISelEmitter (confirmed by diffing the tablegenerated
files). GlobalISelEmitter is currently unable to infer the type of operands in
the Dst pattern from the operands in the Src pattern.

llvm-svn: 307634
2017-07-11 08:57:29 +00:00
Daniel Sanders 3ae33209cc [globalisel][tablegen] Rename and re-comment render functions to match the new MatchTables. NFC.
The conversion to MatchTable left the function names and comments referring to
C++ statements and expressions. Updated the names and comments to account for
the fact that they're no longer unconstrained statements/expressions.

llvm-svn: 307248
2017-07-06 10:37:17 +00:00
Daniel Sanders 9d662d2486 [globalisel][tablegen] Rename and re-comment to match the new MatchTables. NFC.
The conversion to MatchTable left the function names and comments referring to
C++ statements and expressions. Updated the names and comments to account for
the fact that they're no longer unconstrained statements/expressions.

llvm-svn: 307246
2017-07-06 10:06:12 +00:00
Daniel Sanders 85ffd3609f [globalisel][tablegen] Import rules containing intrinsic_wo_chain.
Summary:
As of this patch, 1018 out of 3938 rules are currently imported.

Depends on D32275

Reviewers: qcolombet, kristof.beyls, rovka, t.p.northover, ab, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: dberris, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D32278

llvm-svn: 307240
2017-07-06 08:12:20 +00:00
Daniel Sanders a6cfce6863 [globalisel][tablegen] Finish fixing compile-time regressions by merging the matcher and emitter state machines.
Summary:
Also, made a few minor tweaks to shave off a little more cumulative memory consumption:
* All rules share a single NewMIs instead of constructing their own. Only one
  will end up using it.
* Use MIs.resize(1) instead of MIs.clear();MIs.push_back(I) and prevent
  GIM_RecordInsn from changing MIs[0].

Depends on D33764

Reviewers: rovka, vitalybuka, ab, t.p.northover, qcolombet, aditya_nandakumar

Reviewed By: ab

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D33766

llvm-svn: 307159
2017-07-05 14:50:18 +00:00
Daniel Sanders 805e9cb3fc [globalisel][tablegen] Fix the misuse of STATISTICS() on release builds (like r307088) after r307133.
r307133 brought back a couple instances of the same mistake that was already
fixed by r307088. Fixed it again.

Using NumPatternEmitted as a unique id for the tables is not valid on release
builds since the counters don't count in that case.

llvm-svn: 307146
2017-07-05 12:14:18 +00:00
Daniel Sanders d93a35ae40 [globalisel][tablegen] Added instruction emission to the state-machine-based matcher.
Summary:
This further improves the compile-time regressions that will be caused by a
re-commit of r303259.

Also added included preliminary work in preparation for the multi-insn emitter
since I needed to change the relevant part of the API for this patch anyway.

Depends on D33758

Reviewers: rovka, vitalybuka, ab, t.p.northover, qcolombet, aditya_nandakumar

Reviewed By: ab

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D33764

llvm-svn: 307133
2017-07-05 09:39:33 +00:00
Daniel Sanders c60abe37f2 [globalisel][tablegen] Fix release builds after r307079
Using NumPatternEmitted as a unique id for the tables is not valid on release
builds since the counters don't count in that case.

Also fix an unused variable warning.

llvm-svn: 307088
2017-07-04 15:31:50 +00:00
Daniel Sanders 6ab0daade8 [globalisel][tablegen] Partially fix compile-time regressions by converting matcher to state-machine(s)
Summary:
Replace the matcher if-statements for each rule with a state-machine. This
significantly reduces compile time, memory allocations, and cumulative memory
allocation when compiling AArch64InstructionSelector.cpp.o after r303259 is
recommitted.

The following patches will expand on this further to fully fix the regressions.

Reviewers: rovka, ab, t.p.northover, qcolombet, aditya_nandakumar

Reviewed By: ab

Subscribers: vitalybuka, aemerson, javed.absar, igorb, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D33758

llvm-svn: 307079
2017-07-04 14:35:06 +00:00
Daniel Sanders 320390bab8 [globalisel][tablegen] Post-commit review nits for r306388. NFC
One early exit and a missing assert string.

llvm-svn: 306552
2017-06-28 15:16:03 +00:00
Daniel Sanders 3229198ecd [globalisel][tablegen] Multiple 80-col corrections.
llvm-svn: 306544
2017-06-28 13:50:04 +00:00
Daniel Sanders cc36dbf55d [globalisel][tablegen] Add support for EXTRACT_SUBREG.
Summary:
After this patch, we finally have test cases that require multiple
instruction emission.

Depends on D33590

Reviewers: ab, qcolombet, t.p.northover, rovka, kristof.beyls

Subscribers: javed.absar, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D33596

llvm-svn: 306388
2017-06-27 10:11:39 +00:00
Daniel Sanders a6e2cebf98 [globalisel][tablegen] Add support for COPY_TO_REGCLASS.
Summary:
As part of this
* Emitted instructions now have named MachineInstr variables associated
  with them. This isn't particularly important yet but it's a small step
  towards multiple-insn emission.
* constrainSelectedInstRegOperands() is no longer hardcoded. It's now added
  as the ConstrainOperandsToDefinitionAction() action. COPY_TO_REGCLASS uses
  an alternate constraint mechanism ConstrainOperandToRegClassAction() which
  supports arbitrary constraints such as that defined by COPY_TO_REGCLASS.

Reviewers: ab, qcolombet, t.p.northover, rovka, kristof.beyls, aditya_nandakumar

Reviewed By: ab

Subscribers: javed.absar, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D33590

llvm-svn: 305791
2017-06-20 12:36:34 +00:00
Craig Topper 2b8419a22d [TableGen] Make Record::getValueAsString and getValueAsListOfStrings return StringRefs instead of std::string
Internally both these methods just return the result of getValue on either a StringInit or a CodeInit object. In both cases this returns a StringRef pointing to a string allocated in the BumpPtrAllocator so its not going anywhere. So we can just pass that StringRef along.

This is a fairly naive patch that targets just the build failures caused by this change. There's additional work that can be done to avoid creating std::string at call sites that still think getValueAsString returns a std::string. I'll try to clean those up in future patches.

Differential Revision: https://reviews.llvm.org/D33710

llvm-svn: 304325
2017-05-31 19:01:11 +00:00
Craig Topper 481ff7087f [TableGen] Introduce DagInit::getArgs that returns an ArrayRef. Use it to fix 80 column violations in arg_begin/arg_end. Remove DagInit::args and use getArgs instead. NFC
llvm-svn: 304177
2017-05-29 21:49:34 +00:00
Galina Kistanova 1754fee864 Fixed nondeterminism in RuleMatcher::emit.
llvm-svn: 303829
2017-05-25 01:51:53 +00:00
Daniel Sanders 3334cc017e Fix unused variable warnings after r303678
This should fix lld-x86_64-darwin13

llvm-svn: 303683
2017-05-23 20:02:48 +00:00
Daniel Sanders 452c8aec61 [globalisel][tablegen] Add support for (set $dst, 1) and test X86's OptForSize predicate.
Summary:
It's rare but a small number of patterns use IntInit's at the root of the match.
On X86, one such rule is enabled by the OptForSize predicate and causes the
compiler to use the smaller:
	%0 = MOV32r1
instead of the usual:
	%0 = MOV32ri 1

This patch adds support for matching IntInit's at the root and uses this as a
test case for the optsize attribute that was implemented in r301750

Reviewers: qcolombet, ab, t.p.northover, rovka, kristof.beyls, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D32791

llvm-svn: 303678
2017-05-23 19:33:16 +00:00
Daniel Sanders c244ff6a1e Revert r303259 - [globalisel][tablegen] Import rules containing intrinsic_wo_chain.
It's causing some buildbots to timeout whenever tablegen needs re-compilation,
particularly those with -fsanitize=memory but not only them. A compile time
regression was expected since it triples the amount of SelectionDAG rules we
are able to import but it's currently too high.

llvm-svn: 303542
2017-05-22 10:14:33 +00:00
Daniel Sanders 89e9308623 Re-commit: [globalisel][tablegen] Import rules containing intrinsic_wo_chain.
Summary:
As of this patch, 1018 out of 3938 rules are currently imported.

Depends on D32275

Reviewers: qcolombet, kristof.beyls, rovka, t.p.northover, ab, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: dberris, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D32278

The previous commit failed on test-suite/Bitcode/simd_ops/AArch64_halide_runtime.bc
because isImmOperandEqual() assumed MO was a register operand and that's not
always true.

llvm-svn: 303341
2017-05-18 10:33:36 +00:00
Quentin Colombet a072d13e54 Revert "[globalisel][tablegen] Import rules containing intrinsic_wo_chain."
This reverts commit r303259.

This breaks the GISel bot:
http://lab.llvm.org:8080/green/job/Compiler_Verifiers_GlobalISEL/5163/consoleFull#-134276167849ba4694-19c4-4d7e-bec5-911270d8a58c

llvm-svn: 303313
2017-05-17 23:17:29 +00:00
Daniel Sanders 52c9a0c9f2 [globalisel][tablegen] Import rules containing intrinsic_wo_chain.
Summary:
As of this patch, 1018 out of 3938 rules are currently imported.

Depends on D32275

Reviewers: qcolombet, kristof.beyls, rovka, t.p.northover, ab, aditya_nandakumar

Reviewed By: qcolombet

Subscribers: dberris, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D32278

llvm-svn: 303259
2017-05-17 13:39:49 +00:00
Daniel Sanders ed205a090d [globalisel][tablegen] Require that all registers between instructions of a match are virtual.
Summary:
Without this, it's possible to encounter multiple defs for a register.

This is triggered by the current version of D32868 when applied to trunk.

Reviewers: qcolombet, ab, t.p.northover, rovka, kristof.beyls

Reviewed By: qcolombet

Subscribers: llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D32869

llvm-svn: 303253
2017-05-17 12:43:30 +00:00
Diana Picus eb2057ce1d Fixup r303240: Use llvm::to_string instead of std::to_string
It turns out some of the buildbots don't have std::to_string around,
even in this day and age...

llvm-svn: 303243
2017-05-17 09:25:08 +00:00
Diana Picus 382602f176 [GlobalISel][TableGen] Fix handling of default operands
When looping through a destination pattern's operands to decide how many
default operands we need to introduce, we used to count the "expanded"
number of operands. So if one default operand would be rendered as 2
values, we'd count it as 2 operands, when in fact it needs to count as
only 1 operand regardless of how many values it expands to.

This turns out to be a problem only in some very specific cases, e.g.
when we have one operand with multiple default values followed by more
operands with default values (see the new test). In such a situation
we'd stop looping before looking at all the operands, and then error out
assuming that we don't have enough default operands to make up the
shortfall.

At the moment this only affects ARM.

The patch removes the loop counting default operands entirely and
assumes that we'll have to introduce values for any default operand that
we find (i.e. we're assuming it cannot be given as a child at all). It
also extracts the code for adding renderers for default operands into a
helper method.

Differential Revision: https://reviews.llvm.org/D33031

llvm-svn: 303240
2017-05-17 08:57:28 +00:00
Diana Picus 8abcbbb24b [ARM] GlobalISel: Use TableGen instruction selector
Emit and use the TableGen instruction selector for ARM. At the moment,
this allows us to remove the hand-written code for selecting G_SDIV and
G_UDIV.

Future commits will focus on increasing the code coverage for it and
removing more dead code from the current instruction selector.

llvm-svn: 301905
2017-05-02 09:40:49 +00:00
Daniel Sanders ce9443df23 [globalisel][tablegen] Silence unused variable warning.
llvm-svn: 301755
2017-04-29 19:10:19 +00:00
Daniel Sanders e9fdba39e0 [globalisel][tablegen] Compute available feature bits correctly.
Summary:
Predicate<> now has a field to indicate how often it must be recomputed.
Currently, there are two frequencies, per-module (RecomputePerFunction==0)
and per-function (RecomputePerFunction==1). Per-function predicates are
currently recomputed more frequently than necessary since the only predicate
in this category is cheap to test. Per-module predicates are now computed in
getSubtargetImpl() while per-function predicates are computed in selectImpl().

Tablegen now manages the PredicateBitset internally. It should only be
necessary to add the required includes.

Also fixed a problem revealed by the test case where
constrainSelectedInstRegOperands() would attempt to tie operands that
BuildMI had already tied.

Reviewers: ab, qcolombet, t.p.northover, rovka, aditya_nandakumar

Reviewed By: rovka

Subscribers: kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D32491

llvm-svn: 301750
2017-04-29 17:30:09 +00:00
Igor Breger 1593a741a4 [globalisel][tablegen] Fix vector element size
Summary: Fix vector element size.

Reviewers: dsanders

Reviewed By: dsanders

Subscribers: rovka, llvm-commits, kristof.beyls

Differential Revision: https://reviews.llvm.org/D32537

llvm-svn: 301421
2017-04-26 15:59:05 +00:00
Daniel Sanders 658541fe69 [globalisel][tablegen] Add support for RegisterOperand.
Summary:
It functions just like RegisterClass except that the class is obtained
from a field.

Depends on D31761.

Reviewers: ab, qcolombet, t.p.northover, rovka, kristof.beyls, aditya_nandakumar

Reviewed By: ab

Subscribers: dberris, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D32229

llvm-svn: 301080
2017-04-22 15:53:21 +00:00
Daniel Sanders 2deea1878e [globalisel][tablegen] Revise API for ComplexPattern operands to improve flexibility.
Summary:
Some targets need to be able to do more complex rendering than just adding an
operand or two to an instruction. For example, it may need to insert an
instruction to extract a subreg first, or it may need to perform an operation
on the operand.

In SelectionDAG, targets would create SDNode's to achieve the desired effect
during the complex pattern predicate. This worked because SelectionDAG had a
form of garbage collection that would take care of SDNode's that were created
but not used due to a later predicate rejecting a match. This doesn't translate
well to GlobalISel and the churn was wasteful.

The API changes in this patch enable GlobalISel to accomplish the same thing
without the waste. The API is now:
	InstructionSelector::OptionalComplexRendererFn selectArithImmed(MachineOperand &Root) const;
where Root is the root of the match. The return value can be omitted to
indicate that the predicate failed to match, or a function with the signature
ComplexRendererFn can be returned. For example:
	return OptionalComplexRendererFn(
	       [=](MachineInstrBuilder &MIB) { MIB.addImm(Immed).addImm(ShVal); });
adds two immediate operands to the rendered instruction. Immed and ShVal are
captured from the predicate function.

As an added bonus, this also reduces the amount of information we need to
provide to GIComplexOperandMatcher.

Depends on D31418

Reviewers: aditya_nandakumar, t.p.northover, qcolombet, rovka, ab, javed.absar

Reviewed By: ab

Subscribers: dberris, kristof.beyls, igorb, llvm-commits

Differential Revision: https://reviews.llvm.org/D31761

llvm-svn: 301079
2017-04-22 15:11:04 +00:00
Daniel Sanders 3016d3c6c9 [globalisel][tablegen] Fix PR32733 by checking which instruction operands belong to.
canMutate() was returning true when the operands were all in the same order as
the matched instruction. However, it wasn't checking the operands were actually
on that instruction. This worked when we could only match a single instruction
but the addition of nested instruction matching led to cases where the operands
could be split across multiple instructions. canMutate() now returns false if
operands belong to instructions other than the root of the match.

llvm-svn: 301077
2017-04-22 14:31:28 +00:00
Daniel Sanders e7b0d66080 [globalisel][tablegen] Import SelectionDAG's rule predicates and support the equivalent in GIRule.
Summary:
The SelectionDAG importer now imports rules with Predicate's attached via
Requires, PredicateControl, etc. These predicates are implemented as
bitset's to allow multiple predicates to be tested together. However,
unlike the MC layer subtarget features, each target only pays for it's own
predicates (e.g. AArch64 doesn't have 192 feature bits just because X86
needs a lot).

Both AArch64 and X86 derive at least one predicate from the MachineFunction
or Function so they must re-initialize AvailableFeatures before each
function. They also declare locals in <Target>InstructionSelector so that
computeAvailableFeatures() can use the code from SelectionDAG without
modification.

Reviewers: rovka, qcolombet, aditya_nandakumar, t.p.northover, ab

Reviewed By: rovka

Subscribers: aemerson, rengolin, dberris, kristof.beyls, llvm-commits, igorb

Differential Revision: https://reviews.llvm.org/D31418

llvm-svn: 300993
2017-04-21 15:59:56 +00:00