[llvm] [DAG][X86] Bitfield insertion can combine into SHL + SHRD (PR #220182)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,1614 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=x86_64-- | FileCheck %s --check-prefixes=X64
+; RUN: llc < %s -mtriple=x86_64-- -mattr=+slow-shld | FileCheck %s --check-prefixes=X64-SLOW
+; RUN: llc < %s -mtriple=x86_64-- -mattr=+avx2 | FileCheck %s --check-prefixes=X64-AVX2
+; RUN: llc < %s -mtriple=x86_64-- -mattr=+avx512f,+avx512bw,+avx512vl | FileCheck %s --check-prefixes=X64-AVX512
+; RUN: llc < %s -mtriple=x86_64-- -mattr=+avx512vbmi2,+avx512vl | FileCheck %s --check-prefixes=X64-VBMI2
----------------
RKSimon wrote:

```
; RUN: llc < %s -mtriple=x86_64-- | FileCheck %s --check-prefixes=X64,X64-SSE2
; RUN: llc < %s -mtriple=x86_64-- -mattr=+slow-shld | FileCheck %s --check-prefixes=X64-SLOW
; RUN: llc < %s -mtriple=x86_64-- -mattr=+avx2 | FileCheck %s --check-prefixes=X64,X64-AVX2
; RUN: llc < %s -mtriple=x86_64-- -mattr=+avx512f,+avx512bw,+avx512vl | FileCheck %s --check-prefixes=X64,X64-AVX512
; RUN: llc < %s -mtriple=x86_64-- -mattr=+avx512vbmi2,+avx512vl | FileCheck %s --check-prefixes=X64,X64-VBMI2
```

https://github.com/llvm/llvm-project/pull/220182