[llvm] [VectorCombine][AMDGPU] Narrow Phi of Shuffles. (PR #140188)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,2997 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -mtriple=x86_64-- -mcpu=x86-64 -passes=vector-combine -S %s | FileCheck %s --check-prefixes=CHECK-V1
+; RUN: opt -mtriple=x86_64-- -mcpu=x86-64-v2 -passes=vector-combine -S %s | FileCheck %s --check-prefixes=CHECK-V2
+; RUN: opt -mtriple=x86_64-- -mcpu=x86-64-v3 -passes=vector-combine -S %s | FileCheck %s --check-prefixes=CHECK-V3
+; RUN: opt -mtriple=x86_64-- -mcpu=x86-64-v4 -passes=vector-combine -S %s | FileCheck %s --check-prefixes=CHECK-V4
----------------
RKSimon wrote:

Add common prefix to reduce bloat:
```
; RUN: opt -mtriple=x86_64-- -mcpu=x86-64 -passes=vector-combine -S %s | FileCheck %s --check-prefixes=CHECK,CHECK-V1
; RUN: opt -mtriple=x86_64-- -mcpu=x86-64-v2 -passes=vector-combine -S %s | FileCheck %s --check-prefixes=CHECK,CHECK-V2
; RUN: opt -mtriple=x86_64-- -mcpu=x86-64-v3 -passes=vector-combine -S %s | FileCheck %s --check-prefixes=CHECK,CHECK-V3
; RUN: opt -mtriple=x86_64-- -mcpu=x86-64-v4 -passes=vector-combine -S %s | FileCheck %s --check-prefixes=CHECK,CHECK-V4
```

https://github.com/llvm/llvm-project/pull/140188