[llvm] [VectorCombine] Add foldShuffleOfIntrinsics. (PR #106502)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,82 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -mtriple=riscv64 -mattr=+v -passes=vector-combine -S %s | FileCheck %s
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RKSimon wrote:

rename to "shuffle-of-intrinsics.ll" to match existing style

Please can you duplicate this test file to X86 with the RUN lines:
```
; RUN: opt -mtriple=x86_64-- -mcpu=x86-64 -passes=vector-combine -S %s | FileCheck %s --check-prefix=SSE,SSE2
; RUN: opt -mtriple=x86_64-- -mcpu=x86-64-v2 -passes=vector-combine -S %s | FileCheck %s --check-prefix=SSE,SSE4
; RUN: opt -mtriple=x86_64-- -mcpu=x86-64-v3 -passes=vector-combine -S %s | FileCheck %s --check-prefix=AVX
; RUN: opt -mtriple=x86_64-- -mcpu=x86-64-v4 -passes=vector-combine -S %s | FileCheck %s --check-prefix=AVX
```


https://github.com/llvm/llvm-project/pull/106502