[PATCH] D27932: InstSimplify: Eliminate fabs on known positive

[Matt Arsenault via Phabricator via llvm-commits]

arsenm added inline comments.


================
Comment at: lib/Analysis/ValueTracking.cpp:2614
     if (I->getOperand(0) == I->getOperand(1))
       return true;
     LLVM_FALLTHROUGH;
----------------
efriedma wrote:
> IIRC, A*A->A if A is a NaN, so fabs(x*x) isn't equivalent to x*x.
I think the sign of a NaN is OK to ignore


https://reviews.llvm.org/D27932