6 Commits

Author SHA1 Message Date
Wang, Pengfei
c22dc71b12 [CodeGen][X86] Remove unused trivial check-prefixes from all CodeGen/X86 directory.
I had manually removed unused prefixes from CodeGen/X86 directory for more than 100 tests.
I checked the change history for each of them at the beginning, and then I mainly focused on the format since I found all of the unused prefixes were result from either insensible copy or residuum after functional update.
I think it's OK to remove the remaining X86 tests by script now. I wrote a rough script which works for me in most tests. I put it in llvm/utils temporarily for review and hope it may help other components owners.
The tests in this patch are all generated by the tool and checked by update tool for the autogenerated tests. I skimmed them and checked about 30 tests and didn't find any unexpected changes.

Reviewed By: mtrofin, MaskRay

Differential Revision: https://reviews.llvm.org/D91496
2020-11-16 09:45:55 +08:00
Simon Pilgrim
b3b4727a3e [X86] Replace (most) X86ISD::SHLD/SHRD usage with ISD::FSHL/FSHR generic opcodes (PR39467)
For i32 and i64 cases, X86ISD::SHLD/SHRD are close enough to ISD::FSHL/FSHR that we can use them directly, we just need to account for the operand commutation for SHRD.

The i16 SHLD/SHRD case is annoying as the shift amount is modulo-32 (vs funnel shift modulo-16), so I've added X86ISD::FSHL/FSHR equivalents, which matches the generic implementation in all other terms.

Something I'm slightly concerned with is that ISD::FSHL/FSHR legality is controlled by the Subtarget.isSHLDSlow() feature flag - we don't normally use non-ISA features for this but it allows the DAG combines to continue to operate after legalization in a lot more cases.

The X86 *bits.ll changes are all affected by the same issue - we now have a "FSHR(-1,-1,amt) -> ROTR(-1,amt) -> (-1)" simplification that reduces the dependencies enough for the branch fall through code to mess up.

Differential Revision: https://reviews.llvm.org/D75748
2020-03-11 11:17:49 +00:00
Simon Pilgrim
fb8149cac8 [X86] Add CMOV to i686 BMI/TBM tests
As mentioned on D75748, there is no such target that has BMI/TBM support but not the much older CMOV.
2020-03-06 17:26:20 +00:00
Simon Pilgrim
2d0f20cc04 [X86] Handle COPYs of physregs better (regalloc hints)
Enable enableMultipleCopyHints() on X86.

Original Patch by @jonpa:

While enabling the mischeduler for SystemZ, it was discovered that for some reason a test needed one extra seemingly needless COPY (test/CodeGen/SystemZ/call-03.ll). The handling for that is resulted in this patch, which improves the register coalescing by providing not just one copy hint, but a sorted list of copy hints. On SystemZ, this gives ~12500 less register moves on SPEC, as well as marginally less spilling.

Instead of improving just the SystemZ backend, the improvement has been implemented in common-code (calculateSpillWeightAndHint(). This gives a lot of test failures, but since this should be a general improvement I hope that the involved targets will help and review the test updates.

Differential Revision: https://reviews.llvm.org/D38128

llvm-svn: 342578
2018-09-19 18:59:08 +00:00
Roman Lebedev
5ccae1750b [X86][TLI] DAGCombine: Unfold variable bit-clearing mask to two shifts.
Summary:
This adds a reverse transform for the instcombine canonicalizations
that were added in D47980, D47981.

As discussed later, that was worse at least for the code size,
and potentially for the performance, too.

https://rise4fun.com/Alive/Zmpl

Reviewers: craig.topper, RKSimon, spatel

Reviewed By: spatel

Subscribers: reames, llvm-commits

Differential Revision: https://reviews.llvm.org/D48768

llvm-svn: 336585
2018-07-09 19:06:42 +00:00
Roman Lebedev
93357f52c6 [X86] Add tests for low/high bit clearing with different attributes.
D48768 may turn some of these into shifts.

Reviewers: spatel

Reviewed By: spatel

Subscribers: spatel, RKSimon, llvm-commits, craig.topper

Differential Revision: https://reviews.llvm.org/D48767

llvm-svn: 336224
2018-07-03 19:12:37 +00:00