[llvm] [SelectOpt] Add handling for Select-like operations. (PR #77284)

[David Green via llvm-commits]

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@@ -378,6 +378,15 @@ class TargetTransformInfoImplBase {
 
   bool enableSelectOptimize() const { return true; }
 
+  bool shouldTreatInstructionLikeSelect(Instruction *I) {
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davemgreen wrote:

The new select-like `or(zext(c), x)` is currently only enabled for AArch64. I haven't verified the performance on any other systems. The default is still currently just selects, minus the "logical-and/or" from https://reviews.llvm.org/D138490. I think that adding the option to disable the new or(zext) sounds like a good idea, I've added it for AArch64. Let me know if you thing this should add another option to enable it more generally in this function too.

https://github.com/llvm/llvm-project/pull/77284