[Bug tree-optimization/33576] New: segfault in extract_muldiv for cpu2006 benchmark

[Bug tree-optimization/33576] New: segfault in extract_muldiv for cpu2006 benchmark

[pthaugen at gcc dot gnu dot org]

The following trimmed testcase from 464.h264ref is segfaulting.

int a1[6][4][4];
short b1[16];

int c1;
void CalculateQuantParam(void)
{
  int i, j, k, temp;

   for(k=0; k<6; k++)
      for(j=0; j<4; j++)
        for(i=0; i<4; i++)
        {
          temp = (i<<2)+j;
          a1[k][j][i]  = c1/b1[temp];
        }
}


$ /home/pthaugen/install/gcc/trunk/bin/gcc -c -m32 -O2 -ftree-loop-linear
junk.c
junk.c: In function #CalculateQuantParam#:
junk.c:6: internal compiler error: Segmentation fault
Please submit a full bug report,


Program received signal SIGSEGV, Segmentation fault.
extract_muldiv (t=0xf6efa1c0, c=0xf7de0f60, code=MULT_EXPR,
wide_type=0xf6e60150, 
    strict_overflow_p=0xffaaee08 "")
    at /home/pthaugen/src/gcc/trunk/gcc/gcc/fold-const.c:6008
6008                                       > GET_MODE_SIZE (TYPE_MODE (type)))
(gdb) bt 10
#0  extract_muldiv (t=0xf6efa1c0, c=0xf7de0f60, code=MULT_EXPR,
wide_type=0xf6e60150, 
    strict_overflow_p=0xffaaee08 "")
    at /home/pthaugen/src/gcc/trunk/gcc/gcc/fold-const.c:6008
#1  0x42084484 in ?? ()
#2  0x10212c6c in extract_muldiv (t=<value optimized out>, c=0xf7de0f60, 
    code=MULT_EXPR, wide_type=0xf6e60460, strict_overflow_p=0xffaaeee0 "")
    at /home/pthaugen/src/gcc/trunk/gcc/gcc/fold-const.c:6150
#3  0x22084442 in ?? ()
#4  0x10212f58 in extract_muldiv (t=0xf6f2adc0, c=0xf7de0480, code=MULT_EXPR, 
    wide_type=0xf6e60150, strict_overflow_p=0xffaaeee0 "")
    at /home/pthaugen/src/gcc/trunk/gcc/gcc/fold-const.c:6066
#5  0x42084442 in ?? ()
#6  0x101f1e34 in fold_binary (code=MULT_EXPR, type=0xf6e60150, op0=0xf6f2adc0, 
    op1=0xf7de0480) at /home/pthaugen/src/gcc/trunk/gcc/gcc/fold-const.c:10359
#7  0x42008482 in ?? ()
#8  0x101fcb40 in fold_build2_stat (code=ERROR_MARK, type=0xf7de0f60, op0=0x43, 
    op1=0xf6e60150) at /home/pthaugen/src/gcc/trunk/gcc/gcc/fold-const.c:13560
#9  0x106d5730 in chrec_fold_multiply (type=0xf6e60150, op0=0xf6f2adc0,
op1=0xf7de0480)
    at /home/pthaugen/src/gcc/trunk/gcc/gcc/tree-chrec.c:426


-- 
           Summary: segfault in extract_muldiv for cpu2006 benchmark
           Product: gcc
           Version: 4.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pthaugen at gcc dot gnu dot org
 GCC build triplet: powerpc64-linux
  GCC host triplet: powerpc64-linux
GCC target triplet: powerpc64-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33576

[Bug tree-optimization/33576] segfault in extract_muldiv for cpu2006 benchmark

[rguenth at gcc dot gnu dot org]

------- Comment #1 from rguenth at gcc dot gnu dot org  2007-09-28 09:39 -------
Confirmed.  Also happens on x86_64, -O -ftree-loop-linear.  We have a freed
SSA_NAME in use:

Program received signal SIGSEGV, Segmentation fault.
0x000000000067da2a in extract_muldiv_1 (t=0x2b5d06c1af60, c=0x2b5d062ab180, 
    code=MULT_EXPR, wide_type=0x2b5d06282000, 
    strict_overflow_p=0x7fffa488a0f7 "")
    at /space/rguenther/src/svn/pointer_plus/gcc/fold-const.c:6008
6008                                       > GET_MODE_SIZE (TYPE_MODE (type)))
(gdb) print type
$2 = (tree) 0x0
(gdb) call debug_tree (t)
 <ssa_name 0x2b5d06c1af60 nothrow var <var_decl 0x2b5d06343370 j> def_stmt
<ssa_name 0x2b5d06c1a240>
    version 36 in-free-list>

but linear loop transforms are known to be somewhat broken.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dberlin at gcc dot gnu dot
                   |                            |org, spop at gcc dot gnu dot
                   |                            |org
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
  GCC build triplet|powerpc64-linux             |
   GCC host triplet|powerpc64-linux             |
 GCC target triplet|powerpc64-linux             |powerpc64-linux, x86_64-*-*
   Last reconfirmed|0000-00-00 00:00:00         |2007-09-28 09:39:21
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33576

[Bug tree-optimization/33576] segfault in extract_muldiv for cpu2006 benchmark

[spop at gcc dot gnu dot org]

------- Comment #2 from spop at gcc dot gnu dot org  2007-10-02 19:58 -------
The problem is linked to the fact that we eliminate old induction variables
too early, so we end up with SSA names that were freed in the chrecs.
I'm testing a patch fixing this problem.


-- 

spop at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |spop at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2007-09-28 09:39:21         |2007-10-02 19:58:44
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33576

[Bug tree-optimization/33576] segfault in extract_muldiv for cpu2006 benchmark

[spop at gcc dot gnu dot org]

------- Comment #3 from spop at gcc dot gnu dot org  2007-10-03 15:45 -------
Subject: Bug 33576

Author: spop
Date: Wed Oct  3 15:45:10 2007
New Revision: 128986

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=128986
Log:
2007-10-03  Sebastian Pop  <sebastian.pop@amd.com>

        PR tree-optimization/33576
        * testsuite/gcc.dg/tree-ssa/pr33576.c: New.
        * tree-loop-linear.c (linear_transform_loops): Call remove_iv.
        * lambda.h (lambda_loopnest_to_gcc_loopnest): New parameter.
        (remove_iv): Declared.
        * lambda-code.c (remove_iv): Not static.
        (lambda_loopnest_to_gcc_loopnest): New parameter remove_ivs.
        Don't remove ivs there, save ivs in the buffer.


Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr33576.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/lambda-code.c
    trunk/gcc/lambda.h
    trunk/gcc/tree-loop-linear.c


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33576

[Bug tree-optimization/33576] segfault in extract_muldiv for cpu2006 benchmark

[spop at gcc dot gnu dot org]

------- Comment #4 from spop at gcc dot gnu dot org  2007-10-03 15:47 -------
Fixed.


-- 

spop at gcc dot gnu dot org changed:

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


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33576