[llvm] [SLP] Check the Operands of Copyable elements as well in getBestOperand() (PR #182443)

[Ryan Buchner via llvm-commits]

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@@ -0,0 +1,335 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -passes=slp-vectorizer -slp-threshold=-200 -mtriple=x86_64-unknown-linux -mcpu=core-avx2 -S | FileCheck %s
+
+define i32 @test_commutative() {
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bababuck wrote:

This test hits the `commutative` case, but no reordering occurs. Still working to improve.

https://github.com/llvm/llvm-project/pull/182443