[PATCH] D25126: [InstCombine] fold select X, (ext X), C

[Bjorn Pettersson via llvm-commits]

bjope added a reviewer: bjope.
bjope added inline comments.


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Comment at: lib/Transforms/InstCombine/InstCombineSelect.cpp:966
+      Constant *AllOnesOrOne = ConstantExpr::getCast(ExtOpcode, One, SelType);
+      NewSel = SelectInst::Create(Cond, AllOnesOrOne, C);
+    } else {
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Why aren't you using the Builder here? Is it to avoid an implicit fold by the CreateSelect?
To me it looks like you are using a different style compared to the optimization above involving the trunc.

And I guess that if you use the Builder, then you won't need to explicitly copyMetadata? Or is that missing from the optimization involving the trunc. There was not a single explicit copyMetadata in this file until now.


https://reviews.llvm.org/D25126