Commit Graph

7 Commits

Author SHA1 Message Date
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
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
Daniel Sanders 419efdd55b Revert r300964 + r300970 - [globalisel][tablegen] Import SelectionDAG's rule predicates and support the equivalent in GIRule.
It's causing llvm-clang-x86_64-expensive-checks-win to fail to compile and I
haven't worked out why. Reverting to make it green while I figure it out.

llvm-svn: 300978
2017-04-21 14:09:20 +00:00
Daniel Sanders 279d03527e [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: 300964
2017-04-21 10:27:20 +00:00
Matthias Braun 4a86d456d3 TableGen: Use StringRef instead of const std::string& in return vals.
This will allow to switch to a different string storage in an upcoming
commit.

llvm-svn: 288612
2016-12-04 05:48:16 +00:00
Daniel Sanders 72db2a390a Check that emitted instructions meet their predicates on all targets except ARM, Mips, and X86.
Summary:
* ARM is omitted from this patch because this check appears to expose bugs in this target.
* Mips is omitted from this patch because this check either detects bugs or deliberate
  emission of instructions that don't satisfy their predicates. One deliberate
  use is the SYNC instruction where the version with an operand is correctly
  defined as requiring MIPS32 while the version without an operand is defined
  as an alias of 'SYNC 0' and requires MIPS2.
* X86 is omitted from this patch because it doesn't use the tablegen-erated
  MCCodeEmitter infrastructure.

Patches for ARM and Mips will follow.

Depends on D25617

Reviewers: tstellarAMD, jmolloy

Subscribers: wdng, jmolloy, aemerson, rengolin, arsenm, jyknight, nemanjai, nhaehnle, tstellarAMD, llvm-commits

Differential Revision: https://reviews.llvm.org/D25618

llvm-svn: 287439
2016-11-19 13:05:44 +00:00
Daniel Sanders ea6ef3d3fa [tablegen] Extract portions of AsmMatcherEmitter for re-use by another generator. NFC.
Summary:
This change is preparation for a change that will allow targets to verify that the instructions
they emit meet the predicates they specify. This is useful to ensure that C++
legalization/lowering/instruction-selection doesn't incorrectly select code for a different
subtarget than intended. Such cases are not caught by the integrated assembler when emitting
instructions directly to an object file.

Reviewers: qcolombet

Subscribers: qcolombet, beanz, mgorny, llvm-commits, modocache

Differential Revision: https://reviews.llvm.org/D25614

llvm-svn: 286945
2016-11-15 09:51:02 +00:00