[PATCH] D90901: [X86] Don't fold (fneg (fma (fneg X), Y, (fneg Z))) to (fma X, Y, Z)

[Sanjay Patel via Phabricator via llvm-commits]

spatel added inline comments.


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Comment at: llvm/test/CodeGen/X86/avx2-fma-fneg-combine.ll:2
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
-; RUN: llc < %s -mtriple=i686-unknown-unknown -mattr=+avx2,+fma | FileCheck %s --check-prefix=X32
-; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx2,+fma | FileCheck %s --check-prefix=X64
+; RUN: llc < %s -mtriple=i686-unknown-unknown -mattr=+avx2,+fma --enable-no-signed-zeros-fp-math | FileCheck %s --check-prefix=X32
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+avx2,+fma --enable-no-signed-zeros-fp-math | FileCheck %s --check-prefix=X64
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To confirm: this patch is based on a local update with the test changes?

We really want to avoid adding llc options to toggle the FP state as discussed in D99080 (so this diff would invert what we want to do there).

Unfortunately, this is a yak shaving exercise because the tests are using deprecated target-specific intrinsics. I hopefully fixed that for this file at least here:
8854b27b19

Ideally, we can now add tests with FMF (nsz on the appropriate instructions) to preserve the intent of these tests and also demonstrate the bug.

The fma-fneg-combine.ll file has the same problem. Let me know if I should update that or if you want to give that a try.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D90901/new/

https://reviews.llvm.org/D90901