Commit Graph

263 Commits

Author SHA1 Message Date
Ulrich Weigand 81ee484484 [FPEnv] Fix chain handling regression after 04a8696
Code in getRoot made the assumption that every node in PendingLoads
must always itself have a dependency on the current DAG root node.

After the changes in 04a8696, it turns out that this assumption no
longer holds true, causing wrong codegen in some cases (e.g. stores
after constrained FP intrinsics might get deleted).

To fix this, we now need to make sure that the TokenFactor created
by getRoot always includes the previous root, if there is no implicit
dependency already present.

The original getControlRoot code already has exactly this check,
so this patch simply reuses that code now for getRoot as well.
This fixes the regression.

NFC if no constrained FP intrinsic is present.
2020-01-14 14:10:57 +01:00
Ulrich Weigand 04a86966fb [FPEnv] Fix chain handling for fpexcept.strict nodes
We need to ensure that fpexcept.strict nodes are not optimized away even if
the result is unused. To do that, we need to chain them into the block's
terminator nodes, like already done for PendingExcepts.

This patch adds two new lists of pending chains, PendingConstrainedFP and
PendingConstrainedFPStrict to hold constrained FP intrinsic nodes without
and with fpexcept.strict markers. This allows not only to solve the above
problem, but also to relax chains a bit further by no longer flushing all
FP nodes before a store or other memory access. (They are still flushed
before nodes with other side effects.)

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D72341
2020-01-13 14:38:49 +01:00
aqjune e87d71668e [IR] Redefine Freeze instruction
Summary:
This patch redefines freeze instruction from being UnaryOperator to a subclass of UnaryInstruction.

ConstantExpr freeze is removed, as discussed in the previous review.
FreezeOperator is not added because there's no ConstantExpr freeze.
`freeze i8* null` test is added to `test/Bindings/llvm-c/freeze.ll` as well, because the null pointer-related bug in `tools/llvm-c/echo.cpp` is now fixed.
InstVisitor has visitFreeze now because freeze is not unaryop anymore.

Reviewers: whitequark, deadalnix, craig.topper, jdoerfert, lebedev.ri

Reviewed By: craig.topper, lebedev.ri

Subscribers: regehr, nlopes, mehdi_amini, hiraditya, steven_wu, dexonsmith, jfb, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69932
2019-11-12 10:49:00 +09:00
aqjune 58acbce3de [IR] Add Freeze instruction
Summary:
- Define Instruction::Freeze, let it be UnaryOperator
- Add support for freeze to LLLexer/LLParser/BitcodeReader/BitcodeWriter
  The format is `%x = freeze <ty> %v`
- Add support for freeze instruction to llvm-c interface.
- Add m_Freeze in PatternMatch.
- Erase freeze when lowering IR to SelDag.

Reviewers: deadalnix, hfinkel, efriedma, lebedev.ri, nlopes, jdoerfert, regehr, filcab, delcypher, whitequark

Reviewed By: lebedev.ri, jdoerfert

Subscribers: jfb, kristof.beyls, hiraditya, lebedev.ri, steven_wu, dexonsmith, xbolva00, delcypher, spatel, regehr, trentxintong, vsk, filcab, nlopes, mehdi_amini, deadalnix, llvm-commits

Differential Revision: https://reviews.llvm.org/D29011
2019-11-05 15:54:56 +09:00
Jonas Devlieghere 0eaee545ee [llvm] Migrate llvm::make_unique to std::make_unique
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013
2019-08-15 15:54:37 +00:00
Amara Emerson 829037a914 Factor out SelectionDAG's switch analysis and lowering into a separate component.
In order for GlobalISel to re-use the significant amount of analysis and
optimization code in SDAG's switch lowering, we first have to extract it and
create an interface to be used by both frameworks.

No test changes as it's NFC.

Differential Revision: https://reviews.llvm.org/D62745

llvm-svn: 362857
2019-06-08 00:05:17 +00:00
Tim Northover 3d7a057b0d CodeGen: factor out swifterror value tracking.
llvm-svn: 361607
2019-05-24 08:39:43 +00:00
Guillaume Chatelet e386a01e84 [NFC] Refactor visitIntrinsicCall so it doesn't return a const char*
Summary: API simplification

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61306

llvm-svn: 361140
2019-05-20 11:01:30 +00:00
Guillaume Chatelet a760e69840 Revert "[NFC] Refactor visitIntrinsicCall so it doesn't return a const char*"
This reverts commit 706d3cd6388cc3446aab282f3af879862b10cbed.

llvm-svn: 361130
2019-05-20 09:00:12 +00:00
Guillaume Chatelet fa8c152576 [NFC] Refactor visitIntrinsicCall so it doesn't return a const char*
Summary: API simplification

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61306

llvm-svn: 361129
2019-05-20 08:52:10 +00:00
Hans Wennborg 800b12f90a Switch lowering: exploit unreachable fall-through when lowering case range cluster
In the example below, we would previously emit two range checks, one for cases
1--3 and one for 4--6. This patch makes us exploit the fact that the
fall-through is unreachable and only one range check is necessary.

  switch i32 %i, label %default [
    i32 1,  label %bb1
    i32 2,  label %bb1
    i32 3,  label %bb1
    i32 4,  label %bb2
    i32 5,  label %bb2
    i32 6,  label %bb2
  ]
  default: unreachable

llvm-svn: 357252
2019-03-29 13:40:05 +00:00
Hans Wennborg 5c0d7a24e8 Re-commit r355490 "[CodeGen] Omit range checks from jump tables when lowering switches with unreachable default"
Original commit by Ayonam Ray.

This commit adds a regression test for the issue discovered in the
previous commit: that the range check for the jump table can only be
omitted if the fall-through destination of the jump table is
unreachable, which isn't necessarily true just because the default of
the switch is unreachable.

This addresses the missing optimization in PR41242.

> During the lowering of a switch that would result in the generation of a
> jump table, a range check is performed before indexing into the jump
> table, for the switch value being outside the jump table range and a
> conditional branch is inserted to jump to the default block. In case the
> default block is unreachable, this conditional jump can be omitted. This
> patch implements omitting this conditional branch for unreachable
> defaults.
>
> Differential Revision: https://reviews.llvm.org/D52002
> Reviewers: Hans Wennborg, Eli Freidman, Roman Lebedev

llvm-svn: 357067
2019-03-27 14:10:11 +00:00
Yi Kong 74b874ac4c Fix nondeterminism introduced in r353954
DenseMap iteration order is not guaranteed, use MapVector instead.

Fix provided by srhines.

Differential Revision: https://reviews.llvm.org/D59807

llvm-svn: 356988
2019-03-26 12:18:08 +00:00
Alexander Kornienko 3d467a890e Revert "[CodeGen] Omit range checks from jump tables when lowering switches with unreachable default"
This reverts commit 2a0f2c5ef3 (r355490).

The commit causes an assertion failure when compiling LLVM code:
$ cat repro.cpp
class QQQ {
public:
  bool x() const;
  bool y() const;
  unsigned getSizeInBits() const {
    if (y() || x())
      return getScalarSizeInBits();
    return getScalarSizeInBits() * 2;
  }
  unsigned getScalarSizeInBits() const;
};
int f(const QQQ &Ty) {
  switch (Ty.getSizeInBits()) {
    case 1:
    case 8:
      return 0;
    case 16:
      return 1;
    case 32:
      return 2;
    case 64:
      return 3;
    default:
      __builtin_unreachable();
  }
}
$ clang -O2 -o repro.o repro.cpp
assert.h assertion failed at llvm/include/llvm/ADT/ilist_iterator.h:139 in llvm::ilist_iterator::reference llvm::ilist_iterator<llvm::ilist_detail::node_options<llvm::MachineInstr, true, true, void>, true, false>::operator*() const [OptionsT = llvm::ilist_detail::node_options<llvm::MachineInstr, true, true, void>, IsReverse = true, IsConst = false]: !NodePtr->isKnownSentinel()
*** Check failure stack trace: ***
    @     0x558aab4afc10  __assert_fail
    @     0x558aa885479b  llvm::ilist_iterator<>::operator*()
    @     0x558aa8854715  llvm::MachineInstrBundleIterator<>::operator*()
    @     0x558aa92c33c3  llvm::X86InstrInfo::optimizeCompareInstr()
    @     0x558aa9a9c251  (anonymous namespace)::PeepholeOptimizer::optimizeCmpInstr()
    @     0x558aa9a9b371  (anonymous namespace)::PeepholeOptimizer::runOnMachineFunction()
    @     0x558aa99a4fc8  llvm::MachineFunctionPass::runOnFunction()
    @     0x558aab019fc4  llvm::FPPassManager::runOnFunction()
    @     0x558aab01a3a5  llvm::FPPassManager::runOnModule()
    @     0x558aab01aa9b  (anonymous namespace)::MPPassManager::runOnModule()
    @     0x558aab01a635  llvm::legacy::PassManagerImpl::run()
    @     0x558aab01afe1  llvm::legacy::PassManager::run()
    @     0x558aa5914769  (anonymous namespace)::EmitAssemblyHelper::EmitAssembly()
    @     0x558aa5910f44  clang::EmitBackendOutput()
    @     0x558aa5906135  clang::BackendConsumer::HandleTranslationUnit()
    @     0x558aa6d165ad  clang::ParseAST()
    @     0x558aa6a94e22  clang::ASTFrontendAction::ExecuteAction()
    @     0x558aa590255d  clang::CodeGenAction::ExecuteAction()
    @     0x558aa6a94840  clang::FrontendAction::Execute()
    @     0x558aa6a38cca  clang::CompilerInstance::ExecuteAction()
    @     0x558aa4e2294b  clang::ExecuteCompilerInvocation()
    @     0x558aa4df6200  cc1_main()
    @     0x558aa4e1b37f  ExecuteCC1Tool()
    @     0x558aa4e1a725  main
    @     0x7ff20d56abbd  __libc_start_main
    @     0x558aa4df51c9  _start

llvm-svn: 355515
2019-03-06 15:23:50 +00:00
Ayonam Ray 2a0f2c5ef3 [CodeGen] Omit range checks from jump tables when lowering switches with unreachable default
During the lowering of a switch that would result in the generation of a
jump table, a range check is performed before indexing into the jump
table, for the switch value being outside the jump table range and a
conditional branch is inserted to jump to the default block. In case the
default block is unreachable, this conditional jump can be omitted. This
patch implements omitting this conditional branch for unreachable
defaults.

Differential Revision: https://reviews.llvm.org/D52002
Reviewers: Hans Wennborg, Eli Freidman, Roman Lebedev

llvm-svn: 355490
2019-03-06 10:01:02 +00:00
Ayonam Ray af92b7a3b8 Reversing the commit of revision 355483 since it is giving a regression on a newly added test.
llvm-svn: 355487
2019-03-06 07:51:28 +00:00
Ayonam Ray 6025fa8e30 [CodeGen] Omit range checks from jump tables when lowering switches with unreachable default
During the lowering of a switch that would result in the generation of a
jump table, a range check is performed before indexing into the jump
table, for the switch value being outside the jump table range and a
conditional branch is inserted to jump to the default block. In case the
default block is unreachable, this conditional jump can be omitted. This
patch implements omitting this conditional branch for unreachable
defaults.

Differential Revision: https://reviews.llvm.org/D52002
Reviewers: Hans Wennborg, Eli Freidman, Roman Lebedev

llvm-svn: 355483
2019-03-06 07:27:45 +00:00
Jeremy Morse 291713a596 [DebugInfo][DAG] Either salvage dangling debug info or emit Undef DBG_VALUEs
In this patch SelectionDAG tries to salvage any dbg.values that are going to be
dropped, in case they can be recovered from Values in the current BB. It also
strengthens SelectionDAGs handling of dangling debug data, so that dbg.values
are *always* emitted (as Undef or otherwise) instead of dangling forever.

The motivation behind this patch exists in the new test case: a memory address
(here a bitcast and GEP) exist in one basic block, and a dbg.value referring to
the address is left in the 'next' block. The base pointer is live across all
basic blocks. In current llvm trunk the dbg.value cannot be encoded, and it
isn't even emitted as an Undef DBG_VALUE.

The change is simply: if we're definitely going to drop a dbg.value, repeatedly
apply salvageDebugInfo to its operand until either we find something that can
be encoded, or we can't salvage any further in which case we produce an Undef
DBG_VALUE. To know when we're "definitely going to drop a dbg.value",
SelectionDAG signals SelectionDAGBuilder when all IR instructions have been
encoded to force salvaging. This ensures that any dbg.value that's dangling
after DAG creation will have a corresponding DBG_VALUE encoded. 

Differential Revision: https://reviews.llvm.org/D57694

llvm-svn: 353954
2019-02-13 16:33:05 +00:00
Jeremy Morse 6d3cd3b4ec [DebugInfo][DAG] Refactor dbg.value lowering into its own method
This is a pure copy-and-paste job, moving the logic for lowering dbg.value
intrinsics to SDDbgValues into its own function. This is ahead of adding some
more users of this logic.

Differential Revision: https://reviews.llvm.org/D57697

llvm-svn: 353950
2019-02-13 15:53:10 +00:00
Bjorn Pettersson ecd0960718 [SelectionDAG] Clean up comments in SelectionDAGBuilder.h. NFC
Remove redundant function/variable names from doxygen
comments (as suggested in https://reviews.llvm.org/D57697).

llvm-svn: 353886
2019-02-12 22:11:20 +00:00
Chandler Carruth 3160734af1 [CallSite removal] Migrate the statepoint GC infrastructure to use the
`CallBase` class rather than `CallSite` wrappers.

I pushed this change down through most of the statepoint infrastructure,
completely removing the use of CallSite where I could reasonably do so.
I ended up making a couple of cut-points: generic call handling
(instcombine, TLI, SDAG). As soon as it hit truly generic handling with
users outside the immediate code, I simply transitioned into or out of
a `CallSite` to make this a reasonable sized chunk.

Differential Revision: https://reviews.llvm.org/D56122

llvm-svn: 353660
2019-02-11 07:42:30 +00:00
Craig Topper 784929d045 Implementation of asm-goto support in LLVM
This patch accompanies the RFC posted here:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/127239.html

This patch adds a new CallBr IR instruction to support asm-goto
inline assembly like gcc as used by the linux kernel. This
instruction is both a call instruction and a terminator
instruction with multiple successors. Only inline assembly
usage is supported today.

This also adds a new INLINEASM_BR opcode to SelectionDAG and
MachineIR to represent an INLINEASM block that is also
considered a terminator instruction.

There will likely be more bug fixes and optimizations to follow
this, but we felt it had reached a point where we would like to
switch to an incremental development model.

Patch by Craig Topper, Alexander Ivchenko, Mikhail Dvoretckii

Differential Revision: https://reviews.llvm.org/D53765

llvm-svn: 353563
2019-02-08 20:48:56 +00:00
Bjorn Pettersson 350352c8a5 [SelectionDAG] Cleanup some code comments. NFC
Don't repeat the function name in some doxygen
comments.

(Just a minor cleanup, while testing to push
from the git monorepo setup.)

llvm-svn: 353317
2019-02-06 17:36:18 +00:00
Ayonam Ray a1f6973ade Reversing the checkin for version 352484 as tests are failing.
llvm-svn: 352504
2019-01-29 15:00:50 +00:00
Ayonam Ray 4272af9b3e [CodeGen] Omit range checks from jump tables when lowering switches with unreachable default
During the lowering of a switch that would result in the generation of a 
jump table, a range check is performed before indexing into the jump 
table, for the switch value being outside the jump table range and a 
conditional branch is inserted to jump to the default block. In case the 
default block is unreachable, this conditional jump can be omitted. This 
patch implements omitting this conditional branch for unreachable 
defaults.

Review ID: D52002
Reviewers: Hans Wennborg, Eli Freidman, Roman Lebedev

llvm-svn: 352484
2019-01-29 12:01:32 +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
Ayonam Ray e00606a1b2 Reversing the commit in revision 350186. Revision causes regression in 4
tests.

llvm-svn: 350187
2019-01-01 07:28:55 +00:00
Ayonam Ray c471bb2e67 Omit range checks from jump tables when lowering switches with unreachable
default

During the lowering of a switch that would result in the generation of a jump
table, a range check is performed before indexing into the jump table, for the
switch value being outside the jump table range and a conditional branch is
inserted to jump to the default block. In case the default block is
unreachable, this conditional jump can be omitted. This patch implements
omitting this conditional branch for unreachable defaults.

Review Reference: D52002

llvm-svn: 350186
2019-01-01 06:37:50 +00:00
Cameron McInally cbde0d9c7b [IR] Add a dedicated FNeg IR Instruction
The IEEE-754 Standard makes it clear that fneg(x) and
fsub(-0.0, x) are two different operations. The former is a bitwise
operation, while the latter is an arithmetic operation. This patch
creates a dedicated FNeg IR Instruction to model that behavior.

Differential Revision: https://reviews.llvm.org/D53877

llvm-svn: 346774
2018-11-13 18:15:47 +00:00
Matt Arsenault 81920b0a25 DAG: Add calling convention argument to calling convention funcs
This seems like a pretty glaring omission, and AMDGPU
wants to treat kernels differently from other calling
conventions.

llvm-svn: 338194
2018-07-28 13:25:19 +00:00
Fangrui Song cb0bab86b3 [CodeGen] Fix inconsistent declaration parameter name
llvm-svn: 337200
2018-07-16 18:51:40 +00:00
Sanjay Patel 8652c53d29 [DAG] propagate FMF for all FPMathOperators
This is a simple hack based on what's proposed in D37686, but we can extend it if needed in follow-ups. 
It gets us most of the FMF functionality that we want without adding any state bits to the flags. It 
also intentionally leaves out non-FMF flags (nsw, etc) to minimize the patch.

It should provide a superset of the functionality from D46563 - the extra tests show propagation and 
codegen diffs for fcmp, vecreduce, and FP libcalls.

The PPC log2() test shows the limits of this most basic approach - we only applied 'afn' to the last 
node created for the call. AFAIK, there aren't any libcall optimizations based on the flags currently, 
so that shouldn't make any difference.

Differential Revision: https://reviews.llvm.org/D46854

llvm-svn: 332358
2018-05-15 14:16:24 +00:00
Sanjay Patel c4e4c5b076 [DAG] clean up flag propagation for binops; NFCI
llvm-svn: 332150
2018-05-11 22:45:22 +00:00
Bjorn Pettersson 27a841fe83 [SelectionDAG] Refactor code by adding RegsForValue::getRegsAndSizes(). NFCI
Summary:
Added a helper method in RegsForValue to get a list with
all the <RegNumber, RegSize> pairs that we want to iterate
over in SelectionDAGBuilder::EmitFuncArgumentDbgValue and
in SelectionDAGBuilder::visitIntrinsicCall.

Reviewers: vsk

Reviewed By: vsk

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46360

llvm-svn: 331510
2018-05-04 08:50:48 +00:00
Bjorn Pettersson 304877e5ec Reapply "[SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)"
Summary:
This reverts SVN r331441 (reapplies r331337), together with a fix
in to handle an already existing fragment expression in the
dbg.value that must be fragmented due to a split PHI node.

This should solve the problem seen in PR37321, which was the
reason for the revert of r331337.

The situation in PR37321 is that we have a PHI node like this

   %u.sroa = phi i80 [ %u.sroa.x, %if.x ],
                     [ %u.sroa.y, %if.y ],
                     [ %u.sroa.z, %if.z ]

and a dbg.value like this

  call void @llvm.dbg.value(metadata i80 %u.sroa,
                            metadata !13,
                            metadata !DIExpression(DW_OP_LLVM_fragment, 0, 80))

The phi node is split into three 32-bit PHI nodes

  %30:gr32 = PHI %11:gr32, %bb.4, %14:gr32, %bb.5, %27:gr32, %bb.8
  %31:gr32 = PHI %12:gr32, %bb.4, %15:gr32, %bb.5, %28:gr32, %bb.8
  %32:gr32 = PHI %13:gr32, %bb.4, %16:gr32, %bb.5, %29:gr32, %bb.8

but since the original value only is 80 bits we need to adjust the size
of the last fragment expression, and with this patch we get

  DBG_VALUE debug-use %30:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 0, 32)
  DBG_VALUE debug-use %31:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 32, 32)
  DBG_VALUE debug-use %32:gr32, debug-use $noreg, !"u", !DIExpression(DW_OP_LLVM_fragment, 64, 16)

Reviewers: vsk, aprantl, mstorsjo

Reviewed By: aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D46384

llvm-svn: 331464
2018-05-03 17:04:16 +00:00
Martin Storsjo 67fdea490d Revert "[SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)"
This reverts SVN r331337, see PR37321 for details on the regression
it introduced.

llvm-svn: 331441
2018-05-03 07:09:33 +00:00
Bjorn Pettersson 1c5a05f32c [SelectionDAG] Selection of DBG_VALUE using a PHI node result (pt 2)
Summary:
This is a follow up to rL331182. A PHI node can be split up into
several MIR PHI nodes when being selected. When there is a
dbg.value intrinsic that uses the result of such a PHI node we
need to select several DBG_VALUE instructions, with fragment
expressions, in order to do a correct selection.

Reviewers: rnk, aprantl, vsk

Reviewed By: vsk

Subscribers: mattd, llvm-commits, JDevlieghere, aprantl, gbedwell, rnk

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D46329

llvm-svn: 331337
2018-05-02 06:56:38 +00:00
Craig Topper 2fa1436206 [IR][CodeGen] Remove dependency on EVT from IR/Function.cpp. Move EVT to CodeGen layer.
Currently EVT is in the IR layer only because of Function.cpp needing a very small piece of the functionality of EVT::getEVTString(). The rest of EVT is used in codegen making CodeGen a better place for it.

The previous code converted a Type* to EVT and then called getEVTString. This was only expected to handle the primitive types from Type*. Since there only a few primitive types, we can just print them as strings directly.

Differential Revision: https://reviews.llvm.org/D45017

llvm-svn: 328806
2018-03-29 17:21:10 +00:00
David Blaikie 36a0f226b1 Fix layering by moving ValueTypes.h from CodeGen to IR
ValueTypes.h is implemented in IR already.

llvm-svn: 328397
2018-03-23 23:58:31 +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
Bjorn Pettersson 5c25f88536 [SelectionDAG] Support multiple dangling debug info for one value
Summary:
When building the selection DAG we sometimes need to postpone
the handling of a dbg.value until the value it should refer to
is created. This is done by using the DanglingDebugInfoMap.
In the past this map has been limited to hold one dangling
dbg.value per value. This patch removes that restriction.

Reviewers: aprantl, rnk, probinson, vsk

Reviewed By: aprantl

Subscribers: Ka-Ka, llvm-commits, JDevlieghere

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D44610

llvm-svn: 328084
2018-03-21 09:44:34 +00:00
Bjorn Pettersson a223f815dd [SelectionDAG] Improve handling of dangling debug info
Summary:
1) Make sure to discard dangling debug info if the variable (or
variable fragment) is mapped to something new before we had a
chance to resolve the dangling debug info.

2) When resolving debug info, make sure to bump the associated
SDNodeOrder to ensure that the DBG_VALUE is emitted after the
instruction that defines the value used in the DBG_VALUE.
This will avoid a debug-use before def scenario as seen in
https://bugs.llvm.org/show_bug.cgi?id=36417.

The new test case, test/DebugInfo/X86/sdag-dangling-dbgvalue.ll,
show some other limitations in how dangling debug info is
handled in the SelectionDAG. Since we currently only support
having one dangling dbg.value per Value, we will end up dropping
debug info when there are more than one variable that is described
by the same "dangling value".

Reviewers: aprantl

Reviewed By: aprantl

Subscribers: aprantl, eraman, llvm-commits, JDevlieghere

Tags: #debug-info

Differential Revision: https://reviews.llvm.org/D44369

llvm-svn: 327303
2018-03-12 18:02:39 +00:00
David Blaikie b3bde2ea50 Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).

llvm-svn: 318490
2017-11-17 01:07:10 +00:00
Rong Xu 3573d8da36 [CodeGen] Peel off the dominant case in switch statement in lowering
This patch peels off the top case in switch statement into a branch if the
probability exceeds a threshold. This will help the branch prediction and
avoids the extra compares when lowering into chain of branches.

Differential Revision: http://reviews.llvm.org/D39262

llvm-svn: 318202
2017-11-14 21:44:09 +00:00
Eugene Zelenko fa57bd0ced [CodeGen] Fix some Clang-tidy modernize-use-default-member-init and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 314363
2017-09-27 23:26:01 +00:00
Adrian Prantl 6a57daad81 Improve line debug info when translating a CaseBlock to SDNodes.
The SelectionDAGBuilder translates various conditional branches into
CaseBlocks which are then translated into SDNodes. If a conditional
branch results in multiple CaseBlocks only the first CaseBlock is
translated into SDNodes immediately, the rest of the CaseBlocks are
put in a queue and processed when all LLVM IR instructions in the
basic block have been processed.

When a CaseBlock is transformed into SDNodes the SelectionDAGBuilder
is queried for the current LLVM IR instruction and the resulting
SDNodes are annotated with the debug info of the current
instruction (if it exists and has debug metadata).

When the deferred CaseBlocks are processed, the SelectionDAGBuilder
does not have a current LLVM IR instruction, and the resulting SDNodes
will not have any debuginfo. As DwarfDebug::beginInstruction() outputs
a .loc directive for the first instruction in a labeled
block (typically the case for something coming from a CaseBlock) this
tends to produce a line-0 directive.

This patch changes the handling of CaseBlocks to store the current
instruction's debug info into the CaseBlock when it is created (and the
SelectionDAGBuilder knows the current instruction) and to always use
the stored debug info when translating a CaseBlock to SDNodes.

Patch by Frej Drejhammar!

Differential Revision: https://reviews.llvm.org/D36671

llvm-svn: 311097
2017-08-17 16:57:13 +00:00
Adrian Prantl a617576bb1 Remove the unused dbg.value offset from SelectionDAG (NFC)
Followup to r309426.
rdar://problem/33580047

llvm-svn: 309436
2017-07-28 21:27:35 +00:00
Simon Pilgrim 55a4b6700f Handle ConstantExpr correctly in SelectionDAGBuilder
This change fixes a bug in SelectionDAGBuilder::visitInsertValue and SelectionDAGBuilder::visitExtractValue where constant expressions (InsertValueConstantExpr and ExtractValueConstantExpr) would be treated as non-constant instructions (InsertValueInst and ExtractValueInst). This bug resulted in an incorrect memory access, which manifested as an assertion failure in SDValue::SDValue.

Fixes PR#33094.

Submitted on behalf of @Praetonus (Benoit Vey)

Differential Revision: https://reviews.llvm.org/D34538

llvm-svn: 307502
2017-07-09 16:01:04 +00:00
Simon Dardis 212cccb2f4 Reland "[SelectionDAG] Enable target specific vector scalarization of calls and returns"
By target hookifying getRegisterType, getNumRegisters, getVectorBreakdown,
backends can request that LLVM to scalarize vector types for calls
and returns.

The MIPS vector ABI requires that vector arguments and returns are passed in
integer registers. With SelectionDAG's new hooks, the MIPS backend can now
handle LLVM-IR with vector types in calls and returns. E.g.
'call @foo(<4 x i32> %4)'.

Previously these cases would be scalarized for the MIPS O32/N32/N64 ABI for
calls and returns if vector types were not legal. If vector types were legal,
a single 128bit vector argument would be assigned to a single 32 bit / 64 bit
integer register.

By teaching the MIPS backend to inspect the original types, it can now
implement the MIPS vector ABI which requires a particular method of
scalarizing vectors.

Previously, the MIPS backend relied on clang to scalarize types such as "call
@foo(<4 x float> %a) into "call @foo(i32 inreg %1, i32 inreg %2, i32 inreg %3,
i32 inreg %4)".

This patch enables the MIPS backend to take either form for vector types.

The previous version of this patch had a "conditional move or jump depends on
uninitialized value".

Reviewers: zoran.jovanovic, jaydeep, vkalintiris, slthakur

Differential Revision: https://reviews.llvm.org/D27845

llvm-svn: 305083
2017-06-09 14:37:08 +00:00
Andrew Kaylor f466001eef Add constrained intrinsics for some libm-equivalent operations
Differential revision: https://reviews.llvm.org/D32319

llvm-svn: 303922
2017-05-25 21:31:00 +00:00