[all-commits] [llvm/llvm-project] 67caff: [msan] Improve handling of Intrinsic::is_fpclass a...

[Vitaly Buka via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 67caff6f32bd7846bf2fe9310a789c6729939f37
      https://github.com/llvm/llvm-project/commit/67caff6f32bd7846bf2fe9310a789c6729939f37
  Author: Vitaly Buka <vitalybuka at google.com>
  Date:   2023-04-28 (Fri, 28 Apr 2023)

  Changed paths:
    M llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
    M llvm/test/Instrumentation/MemorySanitizer/is-fpclass.ll

  Log Message:
  -----------
  [msan] Improve handling of Intrinsic::is_fpclass after c55fffe

c55fffe replaced fcmp with fpclass.

```
declare i1 @llvm.is.fpclass(<fptype> <op>, i32 <test>)
declare <N x i1> @llvm.is.fpclass(<vector-fptype> <op>, i32 <test>)
```

Perfect fix will require checking bits of <op> corresponding to <test>
argument. For now just propagate shadow without reporting before
intrinsic. Still existing handling of fcmp is also simple OR, so it's
not making it worse.

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D149491