[PATCH] D38369: [InstSimplify] teach SimplifySelectInst() to fold more vector selects

[Haicheng Wu via Phabricator via llvm-commits]

haicheng added inline comments.


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Comment at: lib/Analysis/InstructionSimplify.cpp:3585
+      if (Constant *CF = dyn_cast<Constant>(FalseVal))
+        return ConstantExpr::getSelect(CB, CT, CF);
     if (CB->isAllOnesValue())
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spatel wrote:
> I think we should use ConstantFoldSelectInstruction() here (to be more efficient?). That's the interface for other opcodes from what I can see in other parts of the file.
I think I cannot use ConstantFoldSelectInstruction() which is declared in IR/ConstantFold.h rather than llvm/Analysis/ConstantFolding.h.  From the comments in IR/ConstantFold.h, ConstantFoldSelectInstruction() is used internal to ConstantExpr::get* methods.

Many ConstantFoldxxx methods used in this file are declared in llvm/Analysis/ConstantFolding.h.  I also find several places in this file calling ConstantExpr::get* methods.


Repository:
  rL LLVM

https://reviews.llvm.org/D38369