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From: "pchang9 at cs dot wisc.edu" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/57810] New: Waste work in validate_const_int()
Date: Wed, 03 Jul 2013 19:00:00 -0000
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X-Bugzilla-Type: new
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X-Bugzilla-Product: gcc
X-Bugzilla-Component: rtl-optimization
X-Bugzilla-Version: 4.9.0
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X-Bugzilla-Severity: normal
X-Bugzilla-Who: pchang9 at cs dot wisc.edu
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57810

            Bug ID: 57810
           Summary: Waste work in validate_const_int()
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pchang9 at cs dot wisc.edu
                CC: nistor1 at illinois dot edu

The problem appears in revision 200588 in version 4.9.

In method "validate_const_int()" in gcc/read-rtl.c, the loop on line 804 should
break immediately after "valid" is set to "0". All the iterations after "valid"
set to "0" do not perform any useful work, at best they just set "valid" again
to "0".