Commit Graph

3282 Commits

Author SHA1 Message Date
Roman Lebedev daa8da1ff4 [InstCombine][NFC] Regenerate select-of-bittest.ll with instnamer pass
As requested by spatel in https://reviews.llvm.org/D45329

llvm-svn: 329349
2018-04-05 21:34:59 +00:00
Roman Lebedev be9a226e21 [InstCombine] [NFC] Add more tests for getting rid of select of bittest (D45108, PR36950 / PR17564)
Summary:
More tests for D45108:
* One use tests
* allow shift to be a variable, too

Reviewers: spatel, craig.topper

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45329

llvm-svn: 329348
2018-04-05 21:34:53 +00:00
Daniel Neilson 367c2aea4e [InstCombine] Properly change GEP type when reassociating loop invariant GEP chains
Summary:
This is a fix to PR37005.

Essentially, rL328539 ([InstCombine] reassociate loop invariant GEP chains to enable LICM) contains a bug
whereby it will convert:
%src = getelementptr inbounds i8, i8* %base, <2 x i64> %val
%res = getelementptr inbounds i8, <2 x i8*> %src, i64 %val2
into:
%src = getelementptr inbounds i8, i8* %base, i64 %val2
%res = getelementptr inbounds i8, <2 x i8*> %src, <2 x i64> %val

By swapping the index operands if the GEPs are in a loop, and %val is loop variant while %val2
is loop invariant.

This fix recreates new GEP instructions if the index operand swap would result in the type
of %src changing from vector to scalar, or vice versa.

Reviewers: sebpop, spatel

Reviewed By: sebpop

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45287

llvm-svn: 329331
2018-04-05 18:51:45 +00:00
Sanjay Patel 37248d35c3 [InstCombine] add test for fneg+fsub with nsz; NFC
There used to be a fold that would handle this case more generally,
but it was removed at rL73243 to fix PR4374:
https://bugs.llvm.org/show_bug.cgi?id=4374

llvm-svn: 329322
2018-04-05 17:40:51 +00:00
Sanjay Patel deaf4f354e [InstCombine] use pattern matchers for fsub --> fadd folds
This allows folding for vectors with undef elements.

llvm-svn: 329316
2018-04-05 17:06:45 +00:00
Sanjay Patel 7becb3ae4b [InstCombine] add tests for fsub --> fadd; NFC
llvm-svn: 329313
2018-04-05 16:51:09 +00:00
Sanjay Patel 2204520e49 [PatternMatch] define m_FNeg using m_FSub
Using cstfp_pred_ty in the definition allows us to match vectors with undef elements.

This replicates the change for m_Not from D44076 / rL326823 and continues
towards making all pattern matchers allow undef elements in vectors.

llvm-svn: 329303
2018-04-05 15:36:55 +00:00
Sanjay Patel 2eaa2a43f8 [InstCombine] add vector and vector undef tests for FP folds; NFC
llvm-svn: 329294
2018-04-05 15:07:35 +00:00
Eric Fiselier 96bbec79b4 [Analysis] Support aligned new/delete functions.
Summary:
Clang's __builtin_operator_new/delete was recently taught about the aligned allocation overloads (r328134). This patch makes LLVM aware of them as well.
This allows the compiler to perform certain optimizations including eliding new/delete calls.

Reviewers: rsmith, majnemer, dblaikie, vsk, bkramer

Reviewed By: bkramer

Subscribers: ckennelly, llvm-commits

Differential Revision: https://reviews.llvm.org/D44769

llvm-svn: 329218
2018-04-04 19:01:51 +00:00
Eric Fiselier e03d45fa8e Revert "[Analysis] Support aligned new/delete functions."
This reverts commit bee3bbd9bdd3ab3364b8fb0cdb6326bc1ae740e0.

llvm-svn: 329217
2018-04-04 18:23:00 +00:00
Eric Fiselier 0d5f3b0281 [Analysis] Support aligned new/delete functions.
Summary:
Clang's __builtin_operator_new/delete was recently taught about the aligned allocation overloads (r328134). This patch makes LLVM aware of them as well.
This allows the compiler to perform certain optimizations including eliding new/delete calls.

Reviewers: rsmith, majnemer, dblaikie, vsk, bkramer

Reviewed By: bkramer

Subscribers: ckennelly, llvm-commits

Differential Revision: https://reviews.llvm.org/D44769

llvm-svn: 329215
2018-04-04 18:12:01 +00:00
Roman Lebedev c0c9ba7ee0 [InstCombine] [NFC] Add tests for getting rid of select of bittest (PR36950 / PR17564)
Summary: See [[ https://bugs.llvm.org/show_bug.cgi?id=36950 | PR36950 ]], [[ https://bugs.llvm.org/show_bug.cgi?id=17564 | PR17564 ]], D45065, D45108

Reviewers: spatel, craig.topper

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45107

llvm-svn: 329198
2018-04-04 14:10:13 +00:00
Sanjay Patel 81b3b10a95 [InstCombine] allow more fmul folds with 'reassoc'
The tests marked with 'FIXME' require loosening the check
in SimplifyAssociativeOrCommutative() to optimize completely;
that's still checking isFast() in Instruction::isAssociative().

llvm-svn: 329121
2018-04-03 22:19:19 +00:00
Daniel Neilson 901acfab0c [InstCombine] Fold compare of int constant against a splatted vector of ints
Summary:
Folding patterns like:
  %vec = shufflevector <4 x i8> %insvec, <4 x i8> undef, <4 x i32> zeroinitializer
  %cast = bitcast <4 x i8> %vec to i32
  %cond = icmp eq i32 %cast, 0
into:
  %ext = extractelement <4 x i8> %insvec, i32 0
  %cond = icmp eq i32 %ext, 0

Combined with existing rules, this allows us to fold patterns like:
  %insvec = insertelement <4 x i8> undef, i8 %val, i32 0
  %vec = shufflevector <4 x i8> %insvec, <4 x i8> undef, <4 x i32> zeroinitializer
  %cast = bitcast <4 x i8> %vec to i32
  %cond = icmp eq i32 %cast, 0
into:
  %cond = icmp eq i8 %val, 0

When we construct a splat vector via a shuffle, and bitcast the vector into an integer type for comparison against an integer constant. Then we can simplify the the comparison to compare the splatted value against the integer constant.

Reviewers: spatel, anna, mkazantsev

Reviewed By: spatel

Subscribers: efriedma, rengolin, llvm-commits

Differential Revision: https://reviews.llvm.org/D44997

llvm-svn: 329087
2018-04-03 17:26:20 +00:00
Reid Kleckner 298ffc609b [InstCombine] Don't strip function type casts from musttail calls
Summary:
The cast simplifications that instcombine does here do not make any
attempt to obey the verifier rules for musttail calls. Therefore we have
to disable them.

Reviewers: efriedma, majnemer, pcc

Subscribers: hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D45186

llvm-svn: 329027
2018-04-02 22:49:44 +00:00
Sanjay Patel cbb0450540 [InstCombine] add folds for icmp + sub (PR36969)
(A - B) >u A --> A <u B
C <u (C - D) --> C <u D

https://rise4fun.com/Alive/e7j

Name: ugt
  %sub = sub i8 %x, %y
  %cmp = icmp ugt i8 %sub, %x
=>
  %cmp = icmp ult i8 %x, %y
  
Name: ult
  %sub = sub i8 %x, %y
  %cmp = icmp ult i8 %x, %sub
=>
  %cmp = icmp ult i8 %x, %y

This should fix:
https://bugs.llvm.org/show_bug.cgi?id=36969

llvm-svn: 329011
2018-04-02 20:37:40 +00:00
Sanjay Patel be0442eeaa [InstCombine] add tests for icmp (sub x, y), x (PR36969); NFC
llvm-svn: 329010
2018-04-02 20:23:54 +00:00
Sebastian Pop d870aea03e [InstCombine] reassociate loop invariant GEP chains to enable LICM
This change brings performance of zlib up by 10%. The example below is from a
hot loop in longest_match() from zlib.

do.body:
  %cur_match.addr.0 = phi i32 [ %cur_match, %entry ], [ %2, %do.cond ]
  %idx.ext = zext i32 %cur_match.addr.0 to i64
  %add.ptr = getelementptr inbounds i8, i8* %win, i64 %idx.ext
  %add.ptr2 = getelementptr inbounds i8, i8* %add.ptr, i64 %idx.ext1
  %add.ptr3 = getelementptr inbounds i8, i8* %add.ptr2, i64 -1

In this example %idx.ext1 is a loop invariant. It will be moved above the use of
loop induction variable %idx.ext such that it can be hoisted out of the loop by
LICM. The operands that have dependences carried by the loop will be sinked down
in the GEP chain. This patch will produce the following output:

do.body:
  %cur_match.addr.0 = phi i32 [ %cur_match, %entry ], [ %2, %do.cond ]
  %idx.ext = zext i32 %cur_match.addr.0 to i64
  %add.ptr = getelementptr inbounds i8, i8* %win, i64 %idx.ext1
  %add.ptr2 = getelementptr inbounds i8, i8* %add.ptr, i64 -1
  %add.ptr3 = getelementptr inbounds i8, i8* %add.ptr2, i64 %idx.ext

llvm-svn: 328539
2018-03-26 16:19:31 +00:00
Sanjay Patel 4fd4fd610c [InstCombine] distribute fmul over fadd/fsub
This replaces a large chunk of code that was looking for compound
patterns that include these sub-patterns. Existing tests ensure that
all of the previous examples are still folded as expected.

We still need to loosen the FMF check.

llvm-svn: 328502
2018-03-26 15:03:57 +00:00
Sanjay Patel 2455fef497 [InstCombine] check uses before creating instructions for fmul distribution
As the tests show, we could create extra instructions without any obvious benefit.

llvm-svn: 328498
2018-03-26 14:25:43 +00:00
Sanjay Patel 93e64dd9a1 [PatternMatch] allow undef elements when matching vector FP +0.0
This continues the FP constant pattern matching improvements from:
https://reviews.llvm.org/rL327627
https://reviews.llvm.org/rL327339
https://reviews.llvm.org/rL327307

Several integer constant matchers also have this ability. I'm
separating matching of integer/pointer null from FP positive zero
and renaming/commenting to make the functionality clearer.

llvm-svn: 328461
2018-03-25 21:16:33 +00:00
Sanjay Patel c84b48ec29 [InstSimplify, InstCombine] add/update tests with FP +0.0 vector with undef; NFC
llvm-svn: 328455
2018-03-25 17:48:20 +00:00
Sanjay Patel e94a85533f [InstCombine] adjust test comments; NFC
llvm-svn: 328450
2018-03-25 14:24:32 +00:00
Sanjay Patel 60d0e119c7 [InstCombine] consolidate casted icmp vector tests
We have thorough coverage of predicates and scalar types,
so we just need a sampling of vector tests to show that
things are working or not with vectors types.

llvm-svn: 328449
2018-03-25 14:19:25 +00:00
Sanjay Patel 841aac04d4 [InstCombine] peek through more icmp of FP cast + bitcast
This is an extension of rL328426 as noted in D44367. 

llvm-svn: 328448
2018-03-25 14:01:42 +00:00
Sanjay Patel 745a9c62c2 [InstCombine] peek through FP casts for sign-bit compares (PR36682)
This pattern came up in PR36682:
https://bugs.llvm.org/show_bug.cgi?id=36682
https://godbolt.org/g/LhuD9A

Equality checks are planned as a follow-up enhancement.

Differential Revision: https://reviews.llvm.org/D44367

llvm-svn: 328426
2018-03-24 15:45:02 +00:00
Sanjay Patel 6a176d527c [InstCombine] add multi-use/vector tests for intrinsic shrinking; NFC
llvm-svn: 328422
2018-03-24 14:45:41 +00:00
Sanjay Patel 9b09fe9f66 [InstCombine] increase test coverage for intrinsic shrinking; NFC
There were no tests with vector types before this.

llvm-svn: 328371
2018-03-23 21:13:53 +00:00
Sanjay Patel cd1f3e7a78 [InstCombine] auto-generate checks; NFC
llvm-svn: 328329
2018-03-23 15:39:03 +00:00
Sanjay Patel 3547dcb3ae [InstSimplify] regenerate checks, move tests; NFC
llvm-svn: 328327
2018-03-23 15:31:31 +00:00
Sanjay Patel d189b596ae [InstCombine] regenerate test checks; NFC
llvm-svn: 328325
2018-03-23 15:19:35 +00:00
Sanjay Patel 94c91b78e7 [InstCombine] add folds for xor-of-icmp signbit tests (PR36682)
This is a retry of r328119 which was reverted at r328145 because
it could crash by trying to combine icmps with different operand
types. This version has a check for that and additional tests.

Original commit message:

This is part of solving:
https://bugs.llvm.org/show_bug.cgi?id=36682

There's also a leftover improvement from the long-ago-closed:
https://bugs.llvm.org/show_bug.cgi?id=5438

https://rise4fun.com/Alive/dC1

llvm-svn: 328197
2018-03-22 14:08:16 +00:00
Sanjay Patel 1d0832d9a3 [InstCombine] move/add tests for fmul distribution; NFC
There are at least 3 problems:
1. We're distributing across large patterns, but fail to do that for the minimal patterns.
2. We're not checking uses, so we may create more instructions than we eliminate.
3. We should be able to do these transforms with less than full 'fast' fmuls.

llvm-svn: 328152
2018-03-21 21:28:19 +00:00
Reid Kleckner 762331be07 Revert r328119 "[InstCombine] add folds for xor-of-icmp signbit tests (PR36682)"
This asserts when compiling safe_numerics_unittest.cpp in Chromium with
MSan.

llvm-svn: 328145
2018-03-21 20:35:36 +00:00
Sanjay Patel 778032f39d [InstCombine] add folds for xor-of-icmp signbit tests (PR36682)
This is part of solving:
https://bugs.llvm.org/show_bug.cgi?id=36682

There's also a leftover improvement from the long-ago-closed:
https://bugs.llvm.org/show_bug.cgi?id=5438

https://rise4fun.com/Alive/dC1

llvm-svn: 328119
2018-03-21 17:17:13 +00:00
Sanjay Patel 3da85ae5a5 [InstCombine] move/add tests for xor-of-icmps (PR36682); NFC
llvm-svn: 328109
2018-03-21 15:54:48 +00:00
Sanjay Patel 0ce3086777 [InstCombine] canonicalize fcmp+select to fabs
This is complicated by -0.0 and nan. This is based on the DAG patterns 
as shown in D44091. I'm hoping that we can just remove those DAG folds 
and always rely on IR canonicalization to handle the matching to fabs.

We would still need to delete the broken code from DAGCombiner to fix 
PR36600:
https://bugs.llvm.org/show_bug.cgi?id=36600

Differential Revision: https://reviews.llvm.org/D44550

llvm-svn: 327858
2018-03-19 15:14:30 +00:00
Roman Lebedev e6da3063a5 [InstCombine] peek through unsigned FP casts for zero-equality compares (PR36682)
Summary:
This pattern came up in PR36682 / D44390
https://bugs.llvm.org/show_bug.cgi?id=36682
https://reviews.llvm.org/D44390
https://godbolt.org/g/oKvT5H

See also D44416

Reviewers: spatel, majnemer, efriedma, arsenm

Reviewed By: spatel

Subscribers: wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D44424

llvm-svn: 327799
2018-03-18 15:53:02 +00:00
Sanjay Patel 63b1028953 [InstCombine] add nnan requirement for sqrt(x) * sqrt(y) -> sqrt(x*y)
This is similar to D43765.

llvm-svn: 327797
2018-03-18 14:32:54 +00:00
Sanjay Patel 2b94927f0d [InstCombine] add nnan requirement to potential fabs folds tests; NFC
As noted in D44550, we can't guarantee preserving the sign-bit of NaN 
if we convert these to fabs().

llvm-svn: 327718
2018-03-16 15:27:39 +00:00
Sanjay Patel 728269c10d [InstCombine] add more tests for fcmp+select -> fabs; NFC
This should correspond to the patterns in D44091 and might
make handling these in the DAG unnecessary.

llvm-svn: 327689
2018-03-16 01:06:33 +00:00
Sanjay Patel 2d568ec0e4 [InstCombine] add tests for fcmp+select -> fabs; NFC
llvm-svn: 327680
2018-03-15 22:48:23 +00:00
Roman Lebedev 6ab60358ca [InstCombine] [NFC] Add tests for peeking through unsigned FP casts for zero-equality compares (PR36682)
Summary:
This pattern came up in PR36682 / D44390
https://bugs.llvm.org/show_bug.cgi?id=36682
https://reviews.llvm.org/D44390
https://godbolt.org/g/oKvT5H

Looking at the IR pattern in question, as per [[ https://github.com/rutgers-apl/alive-nj | alive-nj ]], for all the type combinations i checked
(input: `i16`, `i32`, `i64`; intermediate: `half`/`i16`, `float`/`i32`, `double`/`i64`)
for the following `icmp` comparisons the `uitofp`+`bitcast` can be dropped:
* `eq 0`
* `ne 0`
I did not check vectors, but i'm guessing it's the same there.
{F5889189}

Thus all these cases are in the testcase (along with the vector variant with additional `undef` element in the middle).
There are no negative patterns here (unless alive-nj lied/is broken), all of these should be optimized.

Generated with
{F5889196}

Reviewers: spatel, majnemer, efriedma, arsenm

Reviewed By: spatel

Subscribers: wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D44416

llvm-svn: 327534
2018-03-14 17:31:03 +00:00
Hiroshi Yamauchi e6a3dc7699 Simplify more cases of logical ops of masked icmps.
Summary:
For example,

((X & 255) != 0) && ((X & 15) == 8) -> ((X & 15) == 8).
((X & 7) != 0) && ((X & 15) == 8) -> false.

Reviewers: davidxl

Reviewed By: davidxl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43835

llvm-svn: 327450
2018-03-13 21:13:18 +00:00
Sanjay Patel 204edeca56 [InstCombine] fix fmul reassociation to avoid creating an extra fdiv
This was supposed to be an NFC refactoring that will eventually allow
eliminating the isFast() predicate, but there's a rare possibility
that we would pessimize the code as shown in the test case because
we failed to check 'hasOneUse()' properly. This version also removes
an inefficiency of the old code; we would look for: 
(X * C) * C1 --> X * (C * C1)
...but that pattern is always handled by 
SimplifyAssociativeOrCommutative().

llvm-svn: 327404
2018-03-13 14:46:32 +00:00
Sanjay Patel a71f95404f [InstCombine] add test to show fmul transform creates extra fdiv; NFC
Also, move fmul reassociation tests to the same file as other fmul transforms.

llvm-svn: 327342
2018-03-12 23:10:08 +00:00
Roman Lebedev 92e359ed67 [InstCombine] [NFC] Add tests for peeking through FP casts for sign-bit compares (PR36682)
Summary:
This pattern came up in PR36682:
https://bugs.llvm.org/show_bug.cgi?id=36682
https://godbolt.org/g/LhuD9A

Tests for proposed fix in D44367.

Looking at the IR pattern in question, as per [[ https://github.com/rutgers-apl/alive-nj | alive-nj ]], for all the type combinations i checked
(input: `i16`, `i32`, `i64`; intermediate: `half`/`i16`, `float`/`i32`, `double`/`i64`)
for the following `icmp` comparisons the `sitofp`+`bitcast` can be dropped:
* `eq 0`
* `ne 0`
* `slt 0`
* `sle 0`
* `sge 0`
* `sgt 0`
* `slt 1`
* `sge 1`
* `sle -1`
* `sgt -1`
I did not check vectors, but i'm guessing it's the same there.
{F5887419}

Thus all these cases are in the testcase (along with the vector variant with additional `undef` element in the middle).
There are no negative patterns here (unless alive-nj lied/is broken), all of these should be optimized.

Generated with {F5887551}

Reviewers: spatel, majnemer, efriedma, arsenm

Reviewed By: spatel

Subscribers: nlopes, wdng, llvm-commits

Differential Revision: https://reviews.llvm.org/D44390

llvm-svn: 327301
2018-03-12 17:43:02 +00:00
Sanjay Patel 6ee46702d5 [InstCombine] add tests for casted sign-bit cmp (PR36682); NFC
llvm-svn: 327243
2018-03-11 16:45:31 +00:00
Sanjay Patel 4222716822 [InstSimplify] fp_binop X, undef --> NaN
The variable operand could be NaN, so it's always safe to propagate NaN.

llvm-svn: 327212
2018-03-10 16:51:28 +00:00
Sanjay Patel e5606b4fa5 [ConstantFold] fp_binop AnyConstant, undef --> NaN
With the updated LangRef ( D44216 / rL327138 ) in place, we can proceed with more constant folding.

I'm intentionally taking the conservative path here: no matter what the constant or the FMF, we can 
always fold to NaN. This is because the undef operand can be chosen as NaN, and in our simplified 
default FP env, nothing else happens - NaN just propagates to the result. If we find some way/need 
to propagate undef instead, that can be added subsequently.

The tests show that we always choose the same quiet NaN constant (0x7FF8000000000000 in IR text). 
There were suggestions to improve that with a 'NaN' string token or not always print a 64-bit hex 
value, but those are independent changes. We might also consider setting/propagating the payload of 
NaN constants as an enhancement.

Differential Revision: https://reviews.llvm.org/D44308

llvm-svn: 327208
2018-03-10 15:56:25 +00:00