Commit Graph

9 Commits

Author SHA1 Message Date
Jinsong Ji 3996311ee1 [DAGCombine] reassoc flag shouldn't enable contract
According to IR LangRef, the FMF flag:

contract
Allow floating-point contraction (e.g. fusing a multiply followed by an
addition into a fused multiply-and-add).

reassoc
Allow reassociation transformations for floating-point instructions.
This may dramatically change results in floating-point.

My understanding is that these two flags shouldn't imply each other,
as we might have a SDNode that can be reassociated with others, but
not contractble.

eg: We may want following fmul/fad/fsub to freely reassoc, but don't
want fma being generated here.

   %F = fmul reassoc double %A, %B         ; <double> [#uses=1]
   %G = fmul reassoc double %C, %D         ; <double> [#uses=1]
   %H = fadd reassoc double %F, %G         ; <double> [#uses=1]
   %I = fsub reassoc double %H, %E         ; <double> [#uses=1]

Before https://reviews.llvm.org/D45710, `reassoc` flag actually
did not imply isContratable either.

The current implementation also only check the flag in fadd node,
ignoring fmul node, this patch update that as well.

Reviewed By: spatel, qiucf

Differential Revision: https://reviews.llvm.org/D104247
2021-06-21 21:15:43 +00:00
dfukalov aa77232a63 [NFC][AMDGPU] Improve fused fmul+fadd tests.
Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D84903
2020-07-31 04:00:09 +03:00
Alexander Timofeev 982aee6a38 [AMDGPU] Switch scalarize global loads ON by default
Differential revision: https://reviews.llvm.org/D34407

llvm-svn: 307097
2017-07-04 17:32:00 +00:00
NAKAMURA Takumi e4a741376b Revert r307026, "[AMDGPU] Switch scalarize global loads ON by default"
It broke a testcase.

  Failing Tests (1):
      LLVM :: CodeGen/AMDGPU/alignbit-pat.ll

llvm-svn: 307054
2017-07-04 02:14:18 +00:00
Alexander Timofeev ea7f08bee5 [AMDGPU] Switch scalarize global loads ON by default
Differential revision: https://reviews.llvm.org/D34407

llvm-svn: 307026
2017-07-03 14:54:11 +00:00
Matt Arsenault 3dbeefa978 AMDGPU: Mark all unspecified CC functions in tests as amdgpu_kernel
Currently the default C calling convention functions are treated
the same as compute kernels. Make this explicit so the default
calling convention can be changed to a non-kernel.

Converted with perl -pi -e 's/define void/define amdgpu_kernel void/'
on the relevant test directories (and undoing in one place that actually
wanted a non-kernel).

llvm-svn: 298444
2017-03-21 21:39:51 +00:00
Matt Arsenault 7aad8fd8f4 Enable FeatureFlatForGlobal on Volcanic Islands
This switches to the workaround that HSA defaults to
for the mesa path.

This should be applied to the 4.0 branch.

Patch by Vedran Miletić <vedran@miletic.net>

llvm-svn: 292982
2017-01-24 22:02:15 +00:00
Matt Arsenault 46e6b7adef AMDGPU: Check fast math flags in fadd/fsub combines
llvm-svn: 290312
2016-12-22 04:03:35 +00:00
Matt Arsenault 770ec8680a AMDGPU: Form more FMAs if fusion is allowed
Extend the existing fadd/fsub->fmad combines to produce
FMA if allowed.

llvm-svn: 290311
2016-12-22 03:55:35 +00:00