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From: "hp at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/53508] New: function.c:stack_protect_epilogue call to predict_insn_def with wrong direction of prediction
Date: Mon, 28 May 2012 16:00:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53508

             Bug #: 53508
           Summary: function.c:stack_protect_epilogue call to
                    predict_insn_def with wrong direction of prediction
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
               URL: http://gcc.gnu.org/ml/gcc-patches/2012-05/msg01361.htm
                    l
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: hp@gcc.gnu.org


The message at the URL and the (original) summary says it all; the branch is
*around* a noreturn call, so the call to predict_insn_def has the prediction
direction inverted. The doc wrong too; corrected with revision 187934 on trunk.
The buglet is as far back as the 4.3-branch. The generated code has the call
moved to a "cold" position, so the generated code does not seem to be affected
in the trivial case.