Commit Graph

16 Commits

Author SHA1 Message Date
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
Sanjay Patel 1a6e9ec434 [InstCombine] don't widen an arbitrary sequence of vector ops (PR40032)
The problem is shown specifically for a case with vector multiply here:
https://bugs.llvm.org/show_bug.cgi?id=40032
...and this might mask the original backend bug for ARM shown in:
https://bugs.llvm.org/show_bug.cgi?id=39967

As the test diffs here show, we were (and probably still aren't) doing 
these kinds of transforms in a principled way. We are producing more or 
equal wide instructions than we started with in some cases, so we still 
need to restrict/correct other transforms from overstepping.

If there are perf regressions from this change, we can either carve out 
exceptions to the general IR rules, or improve the backend to do these 
transforms when we know the transform is profitable. That's probably 
similar to a change like D55448.

Differential Revision: https://reviews.llvm.org/D55744

llvm-svn: 349389
2018-12-17 20:27:43 +00:00
Sanjay Patel e49db58616 [InstCombine] regenerate test checks; NFC
llvm-svn: 349307
2018-12-16 16:14:42 +00:00
David Green 184df0c35d Revert commit rL323951
Looks like it's causing timeouts out on at least ppc64le
buildbots.

llvm-svn: 323959
2018-02-01 13:05:25 +00:00
David Green e11f0545db [InstCombine] Allow common type conversions to i8/i16/i32
This, in instcombine, allows conversions to i8/i16/i32 (very
common cases) even if the resulting type is not legal according
to the data layout. This can often open up extra combine
opportunities.

Differential Revision: https://reviews.llvm.org/D42424

llvm-svn: 323951
2018-02-01 11:06:18 +00:00
Sanjay Patel 5f8451afad [InstCombine] use m_APInt to allow ashr folds for vectors with splat constants
llvm-svn: 292064
2017-01-15 16:38:19 +00:00
Sanjay Patel 47e577eb92 [InstCombine] add tests to show likely unwanted select widening; NFC
This is a prerequisite patch for D26556:
https://reviews.llvm.org/D26556

...because there was no direct coverage for these folds (which in some cases are adding instructions).

llvm-svn: 287400
2016-11-18 23:22:00 +00:00
Sanjay Patel da0149dd74 [InstCombine] add tests to show size-increasing select transforms
llvm-svn: 286619
2016-11-11 19:37:54 +00:00
Sanjay Patel 4326c4ac8f [InstCombine] fold select X, (ext X), C
If we're going to canonicalize IR towards select of constants, try harder to create those.
Also, don't lose the metadata.

This is actually 4 related transforms in one patch:
      // select X, (sext X), C --> select X, -1, C
      // select X, (zext X), C --> select X,  1, C
      // select X, C, (sext X) --> select X, C, 0
      // select X, C, (zext X) --> select X, C, 0

Differential Revision: https://reviews.llvm.org/D25126

llvm-svn: 283575
2016-10-07 17:53:07 +00:00
Sanjay Patel f7b851fe84 [InstCombine] allow non-splat folds of select cond (ext X), C
llvm-svn: 282906
2016-09-30 19:49:22 +00:00
Sanjay Patel 75b2518762 [InstCombine] add tests for non-splat select(ext)
llvm-svn: 282901
2016-09-30 19:15:41 +00:00
Sanjay Patel 9685b3eb57 [InstCombine] add tests for select X, (ext X), C
llvm-svn: 282891
2016-09-30 18:10:14 +00:00
Nicolai Haehnle 870bf1788c [InstCombine] try to fold (select C, (sext A), B) into logical ops
Summary:
Turn (select C, (sext A), B) into (sext (select C, A, B')) when A is i1 and
B is a compatible constant, also for zext instead of sext. This will then be
further folded into logical operations.

The transformation would be valid for non-i1 types as well, but other parts of
InstCombine prefer to have sext from non-i1 as an operand of select.

Motivated by the shader compiler frontend in Mesa for AMDGPU, which emits i32
for boolean operations. With this change, the boolean logic is fully
recovered.

Reviewers: majnemer, spatel, tstellarAMD

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D22747

llvm-svn: 277801
2016-08-05 08:22:29 +00:00
Nicolai Haehnle fcac6f8376 [InstCombine] Cleanup select-bitext.ll tests
Follow-up to r277596.

llvm-svn: 277633
2016-08-03 19:10:13 +00:00
Nicolai Haehnle c1f1ad998a [InstCombine] Add select-bitext.ll tests
As requested for D22747.

llvm-svn: 277596
2016-08-03 13:37:56 +00:00