Commit Graph

21 Commits

Author SHA1 Message Date
Clement Courbet fb4aa30f27 [ExpandMemCmp] Allow overlaping loads in the zero-relational case.
Summary:
This allows doing `memcmp(p, q, 7)` with 2 loads instead of a call to
memcmp.
This fixes part of PR45147.

Reviewers: spatel

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D76133
2020-04-02 11:20:47 +02:00
Juneyoung Lee 7aecf2323c [ExpandMemCmp] Correctly set alignment of generated loads
Summary:
This is a part of the series of efforts for correcting alignment of memory operations.
(Another related bugs: https://bugs.llvm.org/show_bug.cgi?id=44388 , https://bugs.llvm.org/show_bug.cgi?id=44543 )

This fixes https://bugs.llvm.org/show_bug.cgi?id=43880 by giving default alignment of loads to 1.

The test CodeGen/AArch64/bcmp-inline-small.ll should have been changed; it was introduced by https://reviews.llvm.org/D64805 . I talked with @evandro, and confirmed that the test is okay to be changed.
Other two tests from PowerPC needed changes as well, but fixes were straightforward.

Reviewers: courbet

Reviewed By: courbet

Subscribers: nlopes, gchatelet, wuzish, nemanjai, kristof.beyls, hiraditya, steven.zhang, danielkiss, llvm-commits, evandro

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D76113
2020-03-16 22:39:48 +09:00
Juneyoung Lee acdcd23b7b Add tests to ExpandMemCmp/X86/memcmp.ll before submitting D76113 2020-03-16 22:19:37 +09:00
Clement Courbet 6518b72f93 [ExpandMemCmp] Properly constant-fold all compares.
Summary:
This gets rid of duplicated code and diverging behaviour w.r.t.
constants.
Fixes PR45086.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75519
2020-03-09 10:40:52 +01:00
Clement Courbet f7e6f5f8e3 [ExpandMemCmp] Properly constant-fold all compares.
Summary:
This gets rid of duplicated code and diverging behaviour w.r.t.
constants.
Fixes PR45086.

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D75519
2020-03-09 09:10:34 +01:00
David Zarzycki f68925d450
[X86] Make memcmp vector lowering handle arbitrary expansions
Teach combineVectorSizedSetCCEquality() to handle arbitrary memcmp
expansions but do not change any default policy for now.

This also fixes a bug in the memcmp expansion itself when large
displacements are needed.

https://reviews.llvm.org/D69507
2019-10-30 09:12:57 +02:00
Dmitri Gribenko 2bf8d77453 Revert "Reland "r364412 [ExpandMemCmp][MergeICmps] Move passes out of CodeGen into opt pipeline.""
This reverts commit r371502, it broke tests
(clang/test/CodeGenCXX/auto-var-init.cpp).

llvm-svn: 371507
2019-09-10 10:39:09 +00:00
Clement Courbet 664d9d2da2 [ExpandMemCmp] Add lit.local.cfg
To prevent AArch64 tests from running when the target is not compiled.

Fixes r371502:

/home/buildslave/ps4-buildslave4/llvm-clang-lld-x86_64-scei-ps4-ubuntu-fast/llvm.src/test/Transforms/ExpandMemCmp/AArch64/memcmp.ll:11:15: error: CHECK-NEXT: expected string not found in input
; CHECK-NEXT: [[TMP0:%.*]] = bitcast i8* [[S1:%.*]] to i64*

llvm-svn: 371503
2019-09-10 10:00:15 +00:00
Clement Courbet 612c260ec3 Reland "r364412 [ExpandMemCmp][MergeICmps] Move passes out of CodeGen into opt pipeline."
With a fix for sanitizer breakage (see explanation in D60318).

llvm-svn: 371502
2019-09-10 09:18:00 +00:00
Clement Courbet 2851248fa1 Revert "r364412 [ExpandMemCmp][MergeICmps] Move passes out of CodeGen into opt pipeline."
Breaks sanitizers:
    libFuzzer :: cxxstring.test
    libFuzzer :: memcmp.test
    libFuzzer :: recommended-dictionary.test
    libFuzzer :: strcmp.test
    libFuzzer :: value-profile-mem.test
    libFuzzer :: value-profile-strcmp.test

llvm-svn: 364416
2019-06-26 12:13:13 +00:00
Clement Courbet 7b3a5f0e6d [ExpandMemCmp][MergeICmps] Move passes out of CodeGen into opt pipeline.
This allows later passes (in particular InstCombine) to optimize more
cases.

One that's important to us is `memcmp(p, q, constant) < 0` and memcmp(p, q, constant) > 0.

llvm-svn: 364412
2019-06-26 11:50:18 +00:00
Fangrui Song ac14f7b10c [lit] Delete empty lines at the end of lit.local.cfg NFC
llvm-svn: 363538
2019-06-17 09:51:07 +00:00
Eric Christopher cee313d288 Revert "Temporarily Revert "Add basic loop fusion pass.""
The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
2019-04-17 04:52:47 +00:00
Eric Christopher a863435128 Temporarily Revert "Add basic loop fusion pass."
As it's causing some bot failures (and per request from kbarton).

This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.

llvm-svn: 358546
2019-04-17 02:12:23 +00:00
Clement Courbet 36a3480385 Re-land r349731 "[CodeGen][ExpandMemcmp] Add an option for allowing overlapping loads.
Update PPC ir following GEP->bitcat to bitcat->GEP->bitcat change.

llvm-svn: 349747
2018-12-20 13:01:04 +00:00
Clement Courbet e22cf4d7cb Revert r349731 "[CodeGen][ExpandMemcmp] Add an option for allowing overlapping loads."
Forgot to update PowerPC tests for the GEP->bitcast change.

llvm-svn: 349733
2018-12-20 09:58:33 +00:00
Clement Courbet 1bb6e1b0f2 [CodeGen][ExpandMemcmp] Add an option for allowing overlapping loads.
Summary:
This allows expanding {7,11,13,14,15,21,22,23,25,26,27,28,29,30,31}-byte memcmp
in just two loads on X86. These were previously calling memcmp.

Reviewers: spatel, gchatelet

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D55263

llvm-svn: 349731
2018-12-20 09:13:47 +00:00
Sanjay Patel 5a48aef3f0 [x86, MemCmpExpansion] allow 2 pairs of loads per block (PR33325)
This is the last step needed to fix PR33325:
https://bugs.llvm.org/show_bug.cgi?id=33325

We're trading branch and compares for loads and logic ops. 
This makes the code smaller and hopefully faster in most cases.

The 24-byte test shows an interesting construct: we load the trailing scalar 
elements into vector registers and generate the same pcmpeq+movmsk code that 
we expected for a pair of full vector elements (see the 32- and 64-byte tests).

Differential Revision: https://reviews.llvm.org/D41714

llvm-svn: 321934
2018-01-06 16:16:04 +00:00
Clement Courbet 063bed9baf re-land [ExpandMemCmp] Split ExpandMemCmp from CodeGen into its own pass."
Fix undefined references: ExpandMemCmp belongs to CodeGen/, not Scalar/.

llvm-svn: 317318
2017-11-03 12:12:27 +00:00
Clement Courbet 82bade615b Revert "[ExpandMemCmp] Split ExpandMemCmp from CodeGen into its own pass."
undefined reference to `llvm::TargetPassConfig::ID' on
clang-ppc64le-linux-multistage

This reverts commit eea333c33fa73ad225ef28607795984829f65688.

llvm-svn: 317213
2017-11-02 15:53:10 +00:00
Clement Courbet 1dc37b9c3b [ExpandMemCmp] Split ExpandMemCmp from CodeGen into its own pass.
Summary:
This is mostly a noop (most of the test diffs are renamed blocks).
There are a few temporary register renames (eax<->ecx) and a few blocks are
shuffled around.

See the discussion in PR33325 for more details.

Reviewers: spatel

Subscribers: mgorny

Differential Revision: https://reviews.llvm.org/D39456

llvm-svn: 317211
2017-11-02 15:02:51 +00:00