[PATCH] D74484: [AggressiveInstCombine] Add support for ICmp instr that feeds a select intsr's condition operand.

[Ayman Musa via Phabricator via llvm-commits]

aymanmus added inline comments.


================
Comment at: llvm/lib/Transforms/AggressiveInstCombine/TruncInstCombine.cpp:356
+      Type *SrcTy = cast<CastInst>(I)->getSrcTy();
+      return Ty->getIntegerBitWidth() >= SrcTy->getIntegerBitWidth();
+    }
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nikic wrote:
> Doesn't the sext/zext case have to check the IsSigned flag as well? I don't think it's as simple as IsSigned => sext and !IsSigned => zext (e.g. it's fine if you have an equality comparison and both use same extension type), but same correctness checks are needed here.
The IsSigned is not relevant in this part of the code.
IsSigned only indicates whether the use of the constant (in case the given Value is a constant) was in a signed or unsigned context. If the Value is not a constant, we don't care about IsSigned.
I'll change the name of the operand to avoid such confusion.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D74484/new/

https://reviews.llvm.org/D74484