[PATCH] D60224: [TargetLowering] Extend bool args to inline-asm according to getBooleanType

Mon May 6 13:54:35 PDT 2019

nickdesaulniers added inline comments.

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Comment at: lib/CodeGen/SelectionDAG/TargetLowering.cpp:3376
+        bool IsBool = C->getConstantIntValue()->getBitWidth() == 1;
+        BooleanContent BCont = getBooleanContents(MVT::i64);
+        ISD::NodeType ExtOpc = IsBool ? getExtendForContent(BCont)
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efriedma wrote:
> Is getBooleanContents really the predicate here?  Despite the name, it's not really an ABI hook; it's specifically supposed to describe the behavior of a few SelectionDAG instructions like ISD::SELECT.  I'd prefer to just say booleans are always zero-extended, unless we come across some case where gcc doesn't do that.
Ok, sounds like ZExt'ing bools when asked to SExt is not the way to go.  We'll have to rebase this or https://reviews.llvm.org/D61560, depending on which lands first ;) . I agree that always Zextending is probably simpler while being correct.

IIUC, the code in the patch and the previous one this is based on only Zext if the boolean is not zero.

Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D60224/new/

https://reviews.llvm.org/D60224