[llvm] [VectorCombine] Add a cost model for shuffleToIdentity. (PR #93937)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,66 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -passes=vector-combine -mtriple=x86_64-- -S %s | FileCheck %s --check-prefix=CHECK
+; RUN: opt -passes=vector-combine -mtriple=x86_64-- -mcpu=corei7-avx -S %s | FileCheck %s --check-prefix=CHECK-AVX
+; RUN: opt -passes=vector-combine -mtriple=x86_64-- -mcpu=core-avx2 -S %s | FileCheck %s --check-prefix=CHECK-AVX2
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RKSimon wrote:

By the looks of it you can test both under CHECK-AVX and remove the CHECK-AVX2 duplicates

https://github.com/llvm/llvm-project/pull/93937