[llvm] [VectorCombine] New folding pattern for extract/binop/shuffle chains (PR #145232)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,18 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt < %s -passes=vector-combine -S | FileCheck %s
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RKSimon wrote:

Rename this to something like shuffle-chain-reduction-umin.ll - move it to x86 and add a variety of cpu targets (x86-64 / x86-64-v2 / x86-64-v3 / x86-64-v4 are often a good base set)  to hopefully show the effect of the cost analysis.

https://github.com/llvm/llvm-project/pull/145232