[llvm-commits] [llvm] r46499 - in /llvm/trunk: lib/Transforms/Scalar/InstructionCombining.cpp test/Transforms/InstCombine/zero-point-zero-add.ll

[Nick Lewycky]

Chris Lattner wrote:
> +    if (const IntrinsicInst *II = dyn_cast<IntrinsicInst>(I))
> +      if (II->getIntrinsicID() == Intrinsic::sqrt)
> +        return CannotBeNegativeZero(II->getOperand(1));

"Unlike sqrt in libm, however, llvm.sqrt has undefined behavior for 
negative numbers (which allows for better optimization)."

I think you can safely return true here.

Nick