Commit Graph

274 Commits

Author SHA1 Message Date
Sanjay Patel 5e13cd2e61 [InstCombine] canonicalize fdiv after fmul if reassociation is allowed
(X / Y) * Z --> (X * Z) / Y

This can allow other optimizations/reassociations as shown in the test diffs.

llvm-svn: 358404
2019-04-15 13:23:38 +00:00
Chen Zheng 87dd0e06dc [InstCombine] Canonicalize (-X srem Y) to -(X srem Y).
Differential Revision: https://reviews.llvm.org/D60647

llvm-svn: 358328
2019-04-13 09:21:22 +00:00
Chen Zheng 5e13ff1da2 [InstCombine] Canonicalize (-X s/ Y) to -(X s/ Y).
Differential Revision: https://reviews.llvm.org/D60395

llvm-svn: 358050
2019-04-10 06:52:09 +00:00
Nikita Popov 2f5e9de8d1 Revert "[InstCombine] [InstCombine] Canonicalize (-X s/ Y) to -(X s/ Y)."
This reverts commit 1383a91689.

sdiv-canonicalize.ll fails after this revision. The fold needs to be
moved outside the branch handling constant operands. However when this
is done there are further test changes, so I'm reverting this in the
meantime.

llvm-svn: 358026
2019-04-09 18:32:38 +00:00
Chen Zheng 1383a91689 [InstCombine] [InstCombine] Canonicalize (-X s/ Y) to -(X s/ Y).
Differential Revision: https://reviews.llvm.org/D60395

llvm-svn: 358017
2019-04-09 16:34:31 +00:00
Sanjay Patel 49d9d17a77 [InstCombine] prevent possible miscompile with sdiv+negate of vector op
Similar to:
rL358005

Forego folding arbitrary vector constants to fix a possible miscompile bug.
We can enhance the transform if we do want to handle the more complicated
vector case.

llvm-svn: 358013
2019-04-09 15:13:03 +00:00
Sanjay Patel 773e04c883 [InstCombine] peek through fdiv to find a squared sqrt
A more general canonicalization between fdiv and fmul would not
handle this case because that would have to be limited by uses
to prevent 2 values from becoming 3 values:
(x/y) * (x/y) --> (x*x) / (y*y)

(But we probably should still have that limited -- but more general --
canonicalization independently of this change.)

llvm-svn: 357943
2019-04-08 21:23:50 +00:00
Craig Topper c1892ec15a [CallSite removal] Remove CallSite uses from InstCombine.
Reviewers: chandlerc

Reviewed By: chandlerc

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D57494

llvm-svn: 352771
2019-01-31 17:23:29 +00:00
Dmitry Venikov 8817658836 [InstCombine] Missed optimization in math expression: simplify calls exp functions
Summary: This patch enables folding following expressions under -ffast-math flag: exp(X) * exp(Y) -> exp(X + Y), exp2(X) * exp2(Y) -> exp2(X + Y). Motivation: https://bugs.llvm.org/show_bug.cgi?id=35594

Reviewers: hfinkel, spatel, efriedma, lebedev.ri

Reviewed By: spatel, lebedev.ri

Subscribers: lebedev.ri, llvm-commits

Differential Revision: https://reviews.llvm.org/D41342

llvm-svn: 352730
2019-01-31 06:28:10 +00:00
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Chen Zheng 4952e668f8 [InstCombine] canonicalize MUL with NEG operand
-X * Y --> -(X * Y)
X * -Y --> -(X * Y)

Differential Revision: https://reviews.llvm.org/D55961

llvm-svn: 350185
2019-01-01 01:09:20 +00:00
Mikael Holmen e3605d0f70 Add a emitUnaryFloatFnCall version that fetches the function name from TLI
Summary:
In several places in the code we use the following pattern:

  if (hasUnaryFloatFn(&TLI, Ty, LibFunc_tan, LibFunc_tanf, LibFunc_tanl)) {
    [...]
    Value *Res = emitUnaryFloatFnCall(X, TLI.getName(LibFunc_tan), B, Attrs);
    [...]
  }

In short, we check if there is a lib-function for a certain type, and then
we _always_ fetch the name of the "double" version of the lib function and
construct a call to the appropriate function, that we just checked exists,
using that "double" name as a basis.

This is of course a problem in cases where the target doesn't support the
"double" version, but e.g. only the "float" version.

In that case TLI.getName(LibFunc_tan) returns "", and
emitUnaryFloatFnCall happily appends an "f" to "", and we erroneously end
up with a call to a function called "f".

To solve this, the above pattern is changed to

  if (hasUnaryFloatFn(&TLI, Ty, LibFunc_tan, LibFunc_tanf, LibFunc_tanl)) {
    [...]
    Value *Res = emitUnaryFloatFnCall(X, &TLI, LibFunc_tan, LibFunc_tanf,
                                      LibFunc_tanl, B, Attrs);
    [...]
  }

I.e instead of first fetching the name of the "double" version and then
letting emitUnaryFloatFnCall() add the final "f" or "l", we let
emitUnaryFloatFnCall() fetch the right name from TLI.

Reviewers: eli.friedman, efriedma

Reviewed By: efriedma

Subscribers: efriedma, bjope, llvm-commits

Differential Revision: https://reviews.llvm.org/D53370

llvm-svn: 344725
2018-10-18 06:27:53 +00:00
Neil Henning 57f5d0a885 [IRBuilder] Fixup CreateIntrinsic to allow specifying Types to Mangle.
The IRBuilder CreateIntrinsic method wouldn't allow you to specify the
types that you wanted the intrinsic to be mangled with. To fix this
I've:

- Added an ArrayRef<Type *> member to both CreateIntrinsic overloads.
- Used that array to pass into the Intrinsic::getDeclaration call.
- Added a CreateUnaryIntrinsic to replace the most common use of
  CreateIntrinsic where the type was auto-deduced from operand 0.
- Added a bunch more unit tests to test Create*Intrinsic calls that
  weren't being tested (including the FMF flag that wasn't checked).

This was suggested as part of the AMDGPU specific atomic optimizer
review (https://reviews.llvm.org/D51969).

Differential Revision: https://reviews.llvm.org/D52087

llvm-svn: 343962
2018-10-08 10:32:33 +00:00
Sanjay Patel 79dceb2903 [InstCombine] name change: foldShuffledBinop -> foldVectorBinop; NFC
This function will deal with more than shuffles with D50992, and I 
have another potential per-element fold that could live here.

llvm-svn: 343692
2018-10-03 15:20:58 +00:00
Sanjay Patel 90a36346bc [InstCombine] refactor mul narrowing folds; NFCI
Similar to rL342278:
The test diffs are all cosmetic due to the change in
value naming, but I'm including that to show that the
new code does perform these folds rather than something
else in instcombine.

D52075 should be able to use this code too rather than
duplicating all of the logic.

llvm-svn: 342292
2018-09-14 22:23:35 +00:00
Craig Topper 4e63db8387 [InstCombine] Fix incorrect usage of getPrimitiveSizeInBits when we should be using the element size for vectors
For vectors, getPrimitiveSizeInBits returns the full vector width. This code should using the element size for vectors. This could be fixed by calling getScalarSizeInBits, but its even easier to just get it from the APInt we're checking.

Differential Revision: https://reviews.llvm.org/D51938

llvm-svn: 341971
2018-09-11 17:57:20 +00:00
Craig Topper a57bb61a3e [InstCombine] Support (mul (sext x), cst) --> (sext (mul x, cst')) and (mul (zext x), cst) --> (zext (mul x, cst')) for vectors constants.
Similar to D51236, but for mul instead of add.

Differential Revision: https://reviews.llvm.org/D51900

llvm-svn: 341961
2018-09-11 16:51:24 +00:00
Sanjay Patel 6d6eab66e0 [InstCombine] fold udiv with common factor from muls with nuw
Unfortunately, sdiv isn't as simple because of UB due to overflow.

This fold is mentioned in PR38239:
https://bugs.llvm.org/show_bug.cgi?id=38239

llvm-svn: 338059
2018-07-26 19:22:41 +00:00
Sanjay Patel 9d2099cc03 [InstCombine] Corrections in comments for division transformation (NFC)
The actual code seems to be correct, but the comments were misleading.

Patch by Aaron Puchert!

Differential Revision: https://reviews.llvm.org/D49276

llvm-svn: 337131
2018-07-15 17:06:59 +00:00
Sanjay Patel 70043b7e9a [InstCombine] return when SimplifyAssociativeOrCommutative makes a change
This bug was created by rL335258 because we used to always call instsimplify
after trying the associative folds. After that change it became possible
for subsequent folds to encounter unsimplified code (and potentially assert
because of it). 

Instead of carrying changed state through instcombine, we can just return 
immediately. This allows instsimplify to run, so we can continue assuming
that easy folds have already occurred.

llvm-svn: 336965
2018-07-13 01:18:07 +00:00
Sanjay Patel 9adea01c9f [InstCombine] simplify code for urem fold; NFCI
llvm-svn: 335623
2018-06-26 16:39:29 +00:00
Sanjay Patel 3575f0c0b3 [InstCombine] fold urem with sext bool divisor
Similar to other patches in this series:
https://reviews.llvm.org/rL335512
https://reviews.llvm.org/rL335527
https://reviews.llvm.org/rL335597
https://reviews.llvm.org/rL335616

...this is filling a gap in analysis that is exposed by an unrelated select-of-constants transform.
I didn't see a way to unify the sext cases because each div/rem opcode results in a different fold.

Note that in this case, the backend might want to convert the select into math:
Name: sext urem
%e = sext i1 %x to i32
%r = urem i32 %y, %e
=>
%c = icmp eq i32 %y, -1
%z = zext i1 %c to i32
%r = add i32 %z, %y

llvm-svn: 335622
2018-06-26 16:30:00 +00:00
Sanjay Patel 7c45debaea [InstCombine] fold udiv with sext bool divisor
Note: I didn't add a hasOneUse() check because the existing,
related fold doesn't have that check. I suspect that the
improved analysis and codegen make these some of the rare
canonicalization cases where we allow an increase in
instructions.

llvm-svn: 335597
2018-06-26 12:41:15 +00:00
Sanjay Patel 38a86d3136 [InstCombine] cleanup udiv folds; NFCI
This removes a "UDivFoldAction" in favor of a simple constant
matcher. In theory, the existing code could do more matching,
but I don't see any evidence or need for it. I've left a TODO
about using ValueTracking in case we see any regressions.

llvm-svn: 335545
2018-06-25 22:50:26 +00:00
Sanjay Patel 6a96d90acd [InstCombine] fold sdiv with sext bool divisor
llvm-svn: 335527
2018-06-25 21:39:41 +00:00
Sanjay Patel 7b0fc75f73 [InstCombine] simplify binops before trying other folds
This is outwardly NFC from what I can tell, but it should be more efficient 
to simplify first (despite the name, SimplifyAssociativeOrCommutative does
not actually simplify as InstSimplify does - it creates/morphs instructions).

This should make it easier to refactor duplicated code that runs for all binops.

llvm-svn: 335258
2018-06-21 17:06:36 +00:00
Serguei Katkov d894fb4288 [InstCombine] Fix div handling
When we optimize select basing on fact that div by 0 is undef
we should not traverse the instruction which are not guaranteed to
transfer execution to next instruction. Guard intrinsic is an example.

Reviewers: spatel, craig.topper
Reviewed By: spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D47576

llvm-svn: 333864
2018-06-04 02:52:36 +00:00
Sanjay Patel bbc6d60677 [InstCombine] call simplify before trying vector folds
As noted in the review thread for rL333782, we could have
made a bug harder to hit if we were simplifying instructions
before trying other folds. 

The shuffle transform in question isn't ever a simplification;
it's just a canonicalization. So I've renamed that to make that 
clearer.

This is NFCI at this point, but I've regenerated the test file 
to show the cosmetic value naming difference of using 
instcombine's RAUW vs. the builder.

Possible follow-ups:
1. Move reassociation folds after simplifies too.
2. Refactor common code; we shouldn't have so much repetition.

llvm-svn: 333820
2018-06-02 16:27:44 +00:00
Omer Paparo Bivas fbb83deef7 [InstCombine] Moving overflow computation logic from InstCombine to ValueTracking; NFC
Differential Revision: https://reviews.llvm.org/D46704

Change-Id: Ifabcbe431a2169743b3cc310f2a34fd706f13f02
llvm-svn: 332026
2018-05-10 19:46:19 +00:00
Adrian Prantl 4dfcc4a788 Remove @brief commands from doxygen comments, too.
This is a follow-up to r331272.

We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by
  for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done

https://reviews.llvm.org/D46290

llvm-svn: 331275
2018-05-01 16:10:38 +00:00
Adrian Prantl 5f8f34e459 Remove \brief commands from doxygen comments.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

  for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
2018-05-01 15:54:18 +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
Sanjay Patel 0e3167cb30 [InstCombine] improve code comment; NFC
llvm-svn: 328560
2018-03-26 17:52:02 +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 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 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 e29375d04c [InstCombine] rearrange visitFMul; NFCI
Put the simplest non-FMF folds first, so it's easier to
see what's left to fix/group/add with the FMF folds.

llvm-svn: 326632
2018-03-02 23:06:45 +00:00
Sanjay Patel 2fd0acf05a [InstCombine] partly fix FMF for fmul+log2 fold
The code was checking that all of the instructions in the 
sequence are 'fast', but that's not necessary. The final 
multiply is all that we need to check (tests adjusted). 
The fmul doesn't need to be fully 'fast' either, but that 
can be another patch.

llvm-svn: 326608
2018-03-02 20:32:46 +00:00
Sanjay Patel d0cdb2f861 [InstCombine] allow fmul fold with less than 'fast'
This is a retry of r326502 with updates to the reassociate 
test file that I missed the first time.

@test15_reassoc in the supposed -reassociate test file 
(except that it tests 2 other passes too...) shows that
there's no clear responsiblity for reassociation transforms.

Instcombine now gets that case, but only because the
constant values are identical. Otherwise, it would still
miss that pattern. 

Reassociate doesn't get that case because it hasn't been 
updated to use less than 'fast' FMF.

llvm-svn: 326513
2018-03-02 00:14:51 +00:00
Sanjay Patel eb5d046890 revert r326502: [InstCombine] allow fmul fold with less than 'fast'
I forgot that I added tests for 'reassoc' to -reassociate, but
suprisingly that file calls -instcombine too, so it is affected.
I'll update that file and try again.

llvm-svn: 326510
2018-03-01 23:39:24 +00:00
Sanjay Patel 7373ae5c9a [InstCombine] allow fmul fold with less than 'fast'
llvm-svn: 326502
2018-03-01 22:53:47 +00:00
Sanjay Patel f3b1af7aa4 [InstCombine] simplify code for (X*Y) * X => (X*X) * Y ; NFCI
llvm-svn: 326444
2018-03-01 15:50:26 +00:00
Sanjay Patel eaf5a120ed [InstCombine] simplify code for X * -1.0 --> -X; NFC
I've added random FMF to one of the tests to show those are propagated.

llvm-svn: 326377
2018-02-28 22:30:04 +00:00
Sanjay Patel b3f4f62698 [InstCombine] move invariant call out of loop; NFC
We really shouldn't need a 2-loop here at all, but that's another cleanup.

llvm-svn: 326330
2018-02-28 16:50:51 +00:00
Sanjay Patel 8fdd87f929 [InstCombine] move constant check into foldBinOpIntoSelectOrPhi; NFCI
Also, rename 'foldOpWithConstantIntoOperand' because that's annoyingly 
vague. The constant check is redundant in some cases, but it allows 
removing duplication for most of the calls.

llvm-svn: 326329
2018-02-28 16:36:24 +00:00
Sanjay Patel 31a90468e1 [InstCombine] allow fdiv folds with less than fully 'fast' ops
Note: gcc appears to allow this fold with -freciprocal-math alone, 
but clang/llvm require more than that with this patch. The wording
in the definitions seems fuzzy enough that it could go either way,
but we'll err on the conservative side of FMF interpretation.

This patch also changes the newly created fmul to have FMF propagated
by the last fdiv rather than intersecting the FMF of the fdivs. This
matches the behavior of other folds near here. The new fmul is only 
used to produce an intermediate op for the final fdiv result, so it
shouldn't be any stricter than that result. The previous behavior
could result in dropping FMF via other folds in instcombine or CSE.

Differential Revision: https://reviews.llvm.org/D43398

llvm-svn: 326098
2018-02-26 16:02:45 +00:00
Sanjay Patel 2db2769499 [InstCombine] simplify code for fabs(X) * fabs(X) -> X * X; NFC
llvm-svn: 325968
2018-02-23 22:38:10 +00:00
Sanjay Patel db53d1847b [InstSimplify] sqrt(X) * sqrt(X) --> X
This was misplaced in InstCombine. We can loosen the FMF as a follow-up step.

llvm-svn: 325965
2018-02-23 22:20:13 +00:00
Sanjay Patel d32104e1b2 [InstCombine] allow fmul-sqrt folds with less than full -ffast-math
Also, add a Builder method for intrinsics to reduce code duplication for clients.

llvm-svn: 325960
2018-02-23 21:16:12 +00:00