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From: "z.zhanghaijian at huawei dot com" <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: Tue, 21 Apr 2020 10:38:53 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D94665

--- Comment #12 from z.zhanghaijian at huawei dot com <z.zhanghaijian at hu=
awei dot com> ---
(In reply to Segher Boessenkool from comment #11)
> Confirmed the comment 4 problem, on all archs.  This is a very old bug.

Ok to me, can this optimization change flag_unsafe_math_optimizations to
flag_finite_math_only?

Like the patch:

diff --git a/gcc/combine.c b/gcc/combine.c
index cff76cd3303..f394d8dfd03 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -6643,7 +6643,7 @@ simplify_if_then_else (rtx x)

   /* Look for MIN or MAX.  */

-  if ((! FLOAT_MODE_P (mode) || flag_unsafe_math_optimizations)
+  if ((! FLOAT_MODE_P (mode) || flag_finite_math_only)
       && comparison_p
       && rtx_equal_p (XEXP (cond, 0), true_rtx)
       && rtx_equal_p (XEXP (cond, 1), false_rtx)

Can this fix the bug=EF=BC=9F=