[PATCH] D47348: [LoopIdiomRecognize] Only convert loops to ctlz if we can prove that the input is non-negative.

[Craig Topper via Phabricator via llvm-commits]

craig.topper added a comment.

The original motivating code is something like the loop in the htest_one_block function here https://github.com/mozilla/mozjpeg/blob/master/jchuff.c


https://reviews.llvm.org/D47348