[Bug rtl-optimization/57106] New: [4.8/4.9 Regression] -fcompare-debug failure with -O2 -fschedule-insns -funroll-all-loops

[Bug rtl-optimization/57106] New: [4.8/4.9 Regression] -fcompare-debug failure with -O2 -fschedule-insns -funroll-all-loops

[zsojka at seznam dot cz]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57106

             Bug #: 57106
           Summary: [4.8/4.9 Regression] -fcompare-debug failure with -O2
                    -fschedule-insns -funroll-all-loops
    Classification: Unclassified
           Product: gcc
           Version: 4.9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: zsojka@seznam.cz


Created attachment 29967
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=29967
reduced testcase

Compiler output:
$ gcc -O2 -fschedule-insns -funroll-all-loops -fcompare-debug testcase.c
gcc: error: testcase.c: -fcompare-debug failure

Tested revisions:
r198366 - fail
4.8 r198018 - fail
4.7 r198018 - OK

[Bug rtl-optimization/57106] [4.8/4.9 Regression] -fcompare-debug failure with -O2 -fschedule-insns -funroll-all-loops

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57106

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.8.1

[Bug rtl-optimization/57106] [4.8/4.9 Regression] -fcompare-debug failure with -O2 -fschedule-insns -funroll-all-loops

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57106

Uros Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|ice-on-valid-code           |
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-04-30
     Ever Confirmed|0                           |1

--- Comment #1 from Uros Bizjak <ubizjak at gmail dot com> 2013-04-30 15:16:35 UTC ---
Confirmed.

[Bug rtl-optimization/57106] [4.8/4.9 Regression] -fcompare-debug failure with -O2 -fschedule-insns -funroll-all-loops

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57106

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> 2013-04-30 21:25:07 UTC ---
Started with http://gcc.gnu.org/r196118 , but that just likely made some latent
scheduler bug no longer latent.

[Bug rtl-optimization/57106] [4.8/4.9 Regression] -fcompare-debug failure with -O2 -fschedule-insns -funroll-all-loops

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57106

Uros Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |ubizjak at gmail dot com,
                   |                            |ysrumyan at gmail dot com

--- Comment #3 from Uros Bizjak <ubizjak at gmail dot com> 2013-05-03 11:49:51 UTC ---
The dependence in i386.c:add_parameter_dependencies adds dependence of the
instruction with wrong index. Proposed patch:

--cut here--
Index: i386.c
===================================================================
--- i386.c      (revision 198569)
+++ i386.c      (working copy)
@@ -24662,7 +24662,7 @@ add_parameter_dependencies (rtx call, rtx head)
          /* Add output depdendence between two function arguments if chain
             of output arguments contains likely spilled HW registers.  */
          if (is_spilled)
-           add_dependence (last, insn, REG_DEP_OUTPUT);
+           add_dependence (first_arg, insn, REG_DEP_OUTPUT);
          first_arg = last = insn;
        }
       else
--cut here--

CC'd author.

[Bug target/57106] [4.8/4.9 Regression] -fcompare-debug failure with -O2 -fschedule-insns -funroll-all-loops

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57106

Uros Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
          Component|rtl-optimization            |target

--- Comment #4 from Uros Bizjak <ubizjak at gmail dot com> 2013-05-03 11:53:35 UTC ---
Target issue.

[Bug target/57106] [4.8/4.9 Regression] -fcompare-debug failure with -O2 -fschedule-insns -funroll-all-loops

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57106

Uros Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
                URL|                            |http://gcc.gnu.org/ml/gcc-p
                   |                            |atches/2013-05/msg00131.htm
                   |                            |l
         AssignedTo|unassigned at gcc dot       |ubizjak at gmail dot com
                   |gnu.org                     |

--- Comment #5 from Uros Bizjak <ubizjak at gmail dot com> 2013-05-03 14:01:55 UTC ---
Patch at [1].

[1] http://gcc.gnu.org/ml/gcc-patches/2013-05/msg00131.html

[Bug target/57106] [4.8/4.9 Regression] -fcompare-debug failure with -O2 -fschedule-insns -funroll-all-loops

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57106

--- Comment #6 from Uros Bizjak <ubizjak at gmail dot com> 2013-05-06 18:57:21 UTC ---
Author: uros
Date: Mon May  6 14:53:03 2013
New Revision: 198629

URL: http://gcc.gnu.org/viewcvs?rev=198629&root=gcc&view=rev
Log:
    PR target/57106
    * config/i386/i386.c (add_parameter_dependencies): Add dependence
    between "first_arg" and "insn", not "last" and "insn".

testsuite/ChangeLog:

    PR target/57106
    * gcc.target/i386/pr57106.c: New test.


Added:
    trunk/gcc/testsuite/gcc.target/i386/pr57106.c
Modified:
    trunk/gcc/config/i386/i386.c

Author: uros
Date: Mon May  6 18:52:02 2013
New Revision: 198638

URL: http://gcc.gnu.org/viewcvs?rev=198638&root=gcc&view=rev
Log:
    Backport from mainline
    2013-05-06  Uros Bizjak  <ubizjak@gmail.com>

    PR target/57106
    * config/i386/i386.c (add_parameter_dependencies): Add dependence
    between "first_arg" and "insn", not "last" and "insn".

testsuite/ChangeLog:

    Backport from mainline
    2013-05-06  Uros Bizjak  <ubizjak@gmail.com>

    PR target/57106
    * gcc.target/i386/pr57106.c: New test.


Added:
    branches/gcc-4_8-branch/gcc/testsuite/gcc.target/i386/pr57106.c
Modified:
    branches/gcc-4_8-branch/gcc/ChangeLog
    branches/gcc-4_8-branch/gcc/config/i386/i386.c
    branches/gcc-4_8-branch/gcc/testsuite/ChangeLog

[Bug target/57106] [4.8/4.9 Regression] -fcompare-debug failure with -O2 -fschedule-insns -funroll-all-loops

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57106

Uros Bizjak <ubizjak at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED

--- Comment #7 from Uros Bizjak <ubizjak at gmail dot com> 2013-05-06 18:57:52 UTC ---
Fixed.