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
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
GIM_CheckNonAtomic has been replaced by GIM_CheckAtomicOrdering to allow it to support a wider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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
MSVC doesn't seem to like implicitly instantiating addPredicate and then
explicitly specializing it later. It causes an internal compiler error.
llvm-svn: 315930
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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