[llvm] [X86] Lower scalar llvm.clmul intrinsics to PCLMULQDQ (#175189) (PR #175216)

[Simon Pilgrim via llvm-commits]

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@@ -3,6 +3,8 @@
 ; RUN: llc < %s -mtriple=x86_64-- -mcpu=x86-64-v2 | FileCheck %s --check-prefixes=CHECK,SSE
 ; RUN: llc < %s -mtriple=x86_64-- -mcpu=x86-64-v3 | FileCheck %s --check-prefixes=CHECK,AVX
 ; RUN: llc < %s -mtriple=x86_64-- -mcpu=x86-64-v4 | FileCheck %s --check-prefixes=CHECK,AVX
+; RUN: llc < %s -mtriple=x86_64-- -mcpu=x86-64 -mattr=+pclmul | FileCheck %s --check-prefixes=PCLMUL,PCLMUL-SSE
+; RUN: llc < %s -mtriple=x86_64-- -mcpu=x86-64 -mattr=+pclmul,+avx | FileCheck %s --check-prefixes=PCLMUL,PCLMUL-AVX
 
 define i8 @clmul_i8(i8 %a, i8 %b) nounwind {
----------------
RKSimon wrote:

Add basic i686 coverage:
```
; RUN: llc < %s -mtriple=i686-- -mattr=+sse2,+pclmul | FileCheck %s --check-prefixes=PCLMUL-X86
```

https://github.com/llvm/llvm-project/pull/175216