[llvm] [InstSimplify] Use multi-op replacement when simplify `select` (PR #121708)

[Nikita Popov via llvm-commits]

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@@ -4372,7 +4383,9 @@ static Value *simplifyWithOpReplaced(Value *V, Value *Op, Value *RepOp,
       // by assumption and this case never wraps, so nowrap flags can be
       // ignored.
       if ((Opcode == Instruction::Sub || Opcode == Instruction::Xor) &&
-          NewOps[0] == RepOp && NewOps[1] == RepOp)
+          any_of(ValidReplacements, [=](const auto &Rep) {
+            return NewOps[0] == NewOps[1] && NewOps[0] == Rep.second;
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nikic wrote:

You can move NewOps[0] == NewOps[1] out of the any_of.

https://github.com/llvm/llvm-project/pull/121708