[PATCH] D62357: [IRBuilder] Add CreateUnOp(...) and CreateFNegFMF(...)

[Cameron McInally via Phabricator via llvm-commits]

cameron.mcinally added inline comments.


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Comment at: llvm/include/llvm/IR/IRBuilder.h:1369
                     MDNode *FPMathTag = nullptr) {
-    if (auto *VC = dyn_cast<Constant>(V))
-      return Insert(Folder.CreateFNeg(VC), Name);
+    if (Value *VC = foldConstant(Instruction::FNeg, V, Name)) return VC;
     return Insert(setFPAttrs(BinaryOperator::CreateFNeg(V), FPMathTag, FMF),
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cameron.mcinally wrote:
> craig.topper wrote:
> > Why can't this keep using Folder.CreateFNeg? CreateNot uses Folder.CreateNot.
> I considered this also and went with something more like CreateBinOp (see CreateUnOp too). The UnOps are odd ducks since they’re not really unary operators, but rather they’re implemented with existing BinOps. IMO, we should be moving away from the weirdness of the UnOps...
> 
> I don’t feel very strongly about this though. If you think the current UnOp direction is better, that’s fine with me. 
Oh oh, I just remembered why I went down the BinOps path. If I’m not mistaken, the Folder.CreateFNeg method throws away FMF when there’s no folder. I wanted to avoid that. I’ll confirm in the morning...


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D62357/new/

https://reviews.llvm.org/D62357