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From: "denis.campredon at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/98026] New: optimization dependant on condition order
Date: Fri, 27 Nov 2020 10:04:35 +0000	[thread overview]
Message-ID: <bug-98026-4@http.gcc.gnu.org/bugzilla/> (raw)

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98026

            Bug ID: 98026
           Summary: optimization dependant on condition order
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: denis.campredon at gmail dot com
  Target Milestone: ---

In all the following functions gcc should recognize that j can't be greater
than 100, and link_error should not appear in assembly. Currently only f3 is
optimized.


-------------------
void link_error();

void f1(int i, int j) {
  if (j > i || i > 100) return;

  if (j > 100) link_error();
}

void f2(int i, int j) {
  if (i > 100 || j > i) return;

  if (j > 100) link_error();
}

void f3(int i, int j) {
  if (i > 100) return;
  if (j > i) return;

  if (j > 100) link_error();
}

void f4(signed int i,unsigned int j) {
  if (i > 100) return;
  if (j > i) return;

  if (j > 100) link_error();
}
------------------

             reply	other threads:[~2020-11-27 10:04 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-27 10:04 denis.campredon at gmail dot com [this message]
2020-11-27 10:52 ` [Bug tree-optimization/98026] " rguenth at gcc dot gnu.org
2021-07-19  4:17 ` pinskia at gcc dot gnu.org
2022-01-12 19:34 ` amacleod at redhat dot com
2022-01-28 23:15 ` amacleod at redhat dot com
2022-01-28 23:18 ` amacleod at redhat dot com

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