[llvm] [InstCombine] Fold operation into select, when one operand is zext of select's condition (PR #166816)

[Andreas Jonson via llvm-commits]

================
@@ -1758,6 +1758,9 @@ static Value *simplifyOperationIntoSelectOperand(Instruction &I, SelectInst *SI,
                                     m_Specific(Op), m_Value(V))) &&
                isGuaranteedNotToBeUndefOrPoison(V)) {
       // Pass
+    } else if (match(Op, m_ZExt(m_Specific(SI->getCondition())))) {
+      V = IsTrueArm ? ConstantInt::get(Op->getType(), 1)
+                    : ConstantInt::getNullValue(Op->getType());
----------------
andjo403 wrote:

I think that it can be a separerat PR when/if there is a use for it

https://github.com/llvm/llvm-project/pull/166816