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From: "segher at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/94665] missed minmax optimization opportunity
 for if/else structure.
Date: Wed, 22 Apr 2020 17:04:11 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94665

--- Comment #17 from Segher Boessenkool <segher at gcc dot gnu.org> ---
[ Please don't add other email addresses for me; I get enough mail already,
  I don't need all bugzilla mail in duplicate :-) ]

(In reply to z.zhanghaijian@huawei.com from comment #16)
> Ok, I will create a new PR to track this bug, and I will submit a bugfix
> patch whit that PR.

You can make this PR RESOLVED again, after you made a new PR.

> In addition, I tracked the process of generating fmaxnm/fminnm and found
> that it was generated in phiopt (minmax_replacement) and if-conversion
> (noce_try_minmax). In the rtl combine, only fminnm can be generated. Is it
> necessary for us to improve this optimization in the rtl combine using the
> above patch in stage1?

Yeah, ifcvt will often do it.

combine can handle max just fine as well; you'll need to track down why
it doesn't here (I noticed it doesn't as well, it wasn't immediately
obvious to me what the difference with the min case is).=