[Bug bootstrap/47187] New: [4.6 Regression] profiledbootstrap failure on i386

[Bug bootstrap/47187] New: [4.6 Regression] profiledbootstrap failure on i386

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47187

           Summary: [4.6 Regression] profiledbootstrap failure on i386
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: bootstrap
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: jakub@gcc.gnu.org


profiledbootstrap currently fails on i386, with --enable-checking=release rtl.c
(copy_rtx) is miscompiled (after giving a bogus warning that copy is
uninitialized (well, in the generated code it is), with checking it ICEs:
../../gcc/rtl.c: In function ‘copy_rtx’:
../../gcc/rtl.c:236:1: error: SSA_NAME_DEF_STMT is wrong
Expected definition statement:
# .MEM_93 = VDEF <.MEM_91>
    D.27976_89 = memcpy (copy.26_86, orig.25_85, 12);

Actual definition statement:
# .MEM_92 = VDEF <.MEM_91>
    D.27976_89 = memcpy (copy.26_86, orig.25_85, D.27973_83);
../../gcc/rtl.c:236:1: internal compiler error: verify_ssa failed
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

This is caused by a bug in gimple_stringop_fixed_value where it doesn't handle
lhs properly.  Small testcase:
char buf[64];
char buf2[64];

void *
foo (char *p, long size)
{
  return __builtin_memcpy (buf, p, size);
}

int
main (void)
{
  long i;
  for (i = 0; i < 65536; i++)
    if (foo ("abcdefghijkl", 12) != buf)
      __builtin_abort ();
  if (foo (buf2, 64) != buf)
    __builtin_abort ();
  return 0;
}

./xgcc -B ./ -O2 -fprofile-generate test.c -o test
./test
./xgcc -B ./ -O2 -fprofile-use test.c -o test

[Bug bootstrap/47187] [4.6 Regression] profiledbootstrap failure on i386

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47187

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1
             Status|UNCONFIRMED                 |ASSIGNED
           Keywords|                            |ice-checking, wrong-code
   Last reconfirmed|                            |2011.01.06 10:06:53
         AssignedTo|unassigned at gcc dot       |jakub at gcc dot gnu.org
                   |gnu.org                     |
     Ever Confirmed|0                           |1
   Target Milestone|---                         |4.6.0

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-01-06 10:06:53 UTC ---
I'll take care of it.

[Bug bootstrap/47187] [4.6 Regression] profiledbootstrap failure on i386

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47187

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-01-06 10:29:49 UTC ---
Created attachment 22911
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=22911
gcc46-pr47187.patch

Very lightly tested fix.

[Bug bootstrap/47187] [4.6 Regression] profiledbootstrap failure on i386

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47187

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-01-07 18:39:14 UTC ---
Author: jakub
Date: Fri Jan  7 18:39:11 2011
New Revision: 168581

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=168581
Log:
    PR bootstrap/47187
    * value-prof.c (gimple_stringop_fixed_value): Handle
    lhs of the call properly.

    * gcc.dg/tree-prof/pr47187.c: New test.

Added:
    trunk/gcc/testsuite/gcc.dg/tree-prof/pr47187.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/value-prof.c

[Bug bootstrap/47187] [4.6 Regression] profiledbootstrap failure on i386

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47187

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

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

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-01-07 18:44:16 UTC ---
Fixed.