On Wed, 28 Sep 2016, Richard Biener wrote:
The following patch implements patterns to catch x / abs (x)
and x / -x, taking advantage of undefinedness at x == 0 as
opposed to the PR having testcases with explicit != 0 checks.
Bootstrap / regtest pending on x86_64-unknown-linux-gnu.
Richard.
2016-09-28 Richard Biener <rguent...@suse.de>
PR middle-end/77407
* match.pd: Add X / abs (X) -> X < 0 ? -1 : 1 and
X / -X -> -1 simplifications.
I notice that we still have the following comment a few lines above:
/* Make sure to preserve divisions by zero. This is the reason why
we don't simplify x / x to 1 or 0 / x to 0. */
Did we give up on preserving divisions by 0? Can we now do the 2
simplifications listed by the comment?
--
Marc Glisse
