[Bug testsuite/55186] New: gcc.dg/const-uniq-1.c fails due to vector expected but not being in the constant pool

[Bug testsuite/55186] New: gcc.dg/const-uniq-1.c fails due to vector expected but not being in the constant pool

[hp at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55186

             Bug #: 55186
           Summary: gcc.dg/const-uniq-1.c fails due to vector expected but
                    not being in the constant pool
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: testsuite
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: hp@gcc.gnu.org
            Target: cris-axis-elf


Created attachment 28601
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28601
const-uniq-1.c.004t.gimple

While technically this is a regression, the reason for the brief PASS period is
likely related to a temporary severe bug in the source tree rather than the
more common sequence: a conscious change foiled by a later bug. This is a rare
event!

This test previously failed, started passing somewhere in the (]-range
193059:193061 (likely due to the bug in r193061) and started failing again
somewhere in the (]-range 193063:193070 (likely due to the bugfix in r193064).
At r193109, the const-uniq-1.c.004t.gimple dump is as attached: no label
present for the expected constant-pool entry.

The assembly output for the vector initializations are piecewise, one for each
element:
        moveq 1,$r9
        move.d $r9,[$sp+4]
The test assumes a single vector in the constant pool supposedly used with some
memcpy-equivalent (call or in-line expansion).  At first glance, the piecewise
initialization might seem suboptimal, but a memcpy call would *not* be better
for -Os for this target, when counting the constant vector (well, twice). 
Piecewise initialization would be optimal - if the storing instructions use
post-increment instead of indexing, as expected by the specified relevant
target macros.  (N.B.: poor autoincdec generation is a long-standing flaw in
gcc covered by PRs elsewhere).
Constant-pool vectors and memcpy are optimal for e.g. vectors four times as
large; will propose such a patch for this test-case.

[Bug testsuite/55186] gcc.dg/const-uniq-1.c fails due to vector expected but not being in the constant pool

[hp at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55186

Hans-Peter Nilsson <hp at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2012-11-03
         AssignedTo|unassigned at gcc dot       |hp at gcc dot gnu.org
                   |gnu.org                     |
     Ever Confirmed|0                           |1

[Bug testsuite/55186] gcc.dg/const-uniq-1.c fails due to vector expected but not being in the constant pool

[hp at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55186

--- Comment #1 from Hans-Peter Nilsson <hp at gcc dot gnu.org> 2012-11-05 22:17:18 UTC ---
Author: hp
Date: Mon Nov  5 22:17:14 2012
New Revision: 193194

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=193194
Log:
    PR testsuite/55186
    * gcc.dg/const-uniq-1.c (a): Increase length four times.

Modified:
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/const-uniq-1.c

[Bug testsuite/55186] gcc.dg/const-uniq-1.c fails due to vector expected but not being in the constant pool

[hp at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55186

Hans-Peter Nilsson <hp at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |4.8.0

[Bug testsuite/55186] gcc.dg/const-uniq-1.c fails due to vector expected but not being in the constant pool

[hp at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55186

Hans-Peter Nilsson <hp at gcc dot gnu.org> changed:

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

--- Comment #2 from Hans-Peter Nilsson <hp at gcc dot gnu.org> 2012-11-06 05:15:46 UTC ---
.