[llvm] [X86] Recognise VPMADD52L pattern with AVX512IFMA/AVXIFMA (#153787) (PR #156714)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,217 @@
+; RUN: llc < %s -O1 -mtriple=x86_64-unknown-unknown | FileCheck %s --check-prefixes=X64
----------------
RKSimon wrote:

don't use attributes (which should allow you to remove alot of duplicate tests below) - we need to use a selection of RUN lines:
```
; RUN: llc < %s -mtriple=x86_64-- -mattr=+avxifma | FileCheck %s --check-prefixes=X64,AVX
; RUN: llc < %s -mtriple=x86_64-- -mattr=+avx512ifma | FileCheck %s --check-prefixes=X64,AVX512,AVX512-NOVL
; RUN: llc < %s -mtriple=x86_64-- -mattr=+avx512ifma,+avx512vl | FileCheck %s --check-prefixes=X64,AVX512,AVX512VL
```

https://github.com/llvm/llvm-project/pull/156714