[Bug c/11380] New: [ia64] stack frame > 2 GB and no optimization results in SEGV

["edwardsg at sgi dot com" <gcc-bugzilla at gcc dot gnu dot org>]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11380

           Summary: [ia64] stack frame > 2 GB and no optimization results in
                    SEGV
           Product: gcc
           Version: 3.3
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: edwardsg at sgi dot com
                CC: gcc-bugs at gcc dot gnu dot org

On ia64, gcc produces bad code for stack frames greater than 2 GB when no
optimization is used.  It works fine with -O1 and above.  This results in the
application core dumping from a SEGV.  For example:

$ cat test.c
int test() {
        char    buf[4000000000];
        bzero(buf, sizeof(buf));
}

$ gcc -v
Reading specs from /usr/local/lib/gcc-lib/ia64-unknown-linux-gnu/3.3/specs
Configured with: ./configure
Thread model: posix
gcc version 3.3

$ gcc -c test.c
$ objdump -d test.o
 
test.o:     file format elf64-ia64-little
 
Disassembly of section .text:
 
0000000000000000 <test>:
   0:   0c 08 19 08 80 05       [MFI]       alloc r33=ar.pfs,6,4,0
   6:   00 00 00 02 00 40                   nop.f 0x0
   c:   04 60 00 84                         mov r34=r12
  10:   05 00 00 00 01 80       [MLX]       nop.m 0x0
  16:   11 ff ff ff 7f 20                   movl r17=0xffffffff1194d800;;
  1c:   02 80 c2 6e
  20:   00 60 30 22 00 20       [MII]       add r12=r12,r17
  26:   30 02 04 00 42 00                   mov r35=r1
  2c:   04 00 c4 00                         mov r32=b0
  30:   05 00 00 00 01 80       [MLX]       nop.m 0x0
  36:   11 00 00 00 00 80                   movl r36=0x1194d810;;
                                            ^^^^^^^^^^^^^^^^^^^^^
                                            should be 0xffffffff1194d810 
  3c:   04 81 c2 66
  40:   04 20 91 44 00 60       [MLX]       add r36=r36,r34
  46:   ee 00 00 00 00 a0                   movl r37=0xee6b2800
  4c:   04 70 41 61
  50:   1c 00 00 00 01 00       [MFB]       nop.m 0x0
  56:   00 00 00 02 00 00                   nop.f 0x0
  5c:   08 00 00 50                         br.call.sptk.many b0=50 <test+0x50>
  60:   02 08 00 46 00 21       [MII]       mov r1=r35
  66:   80 00 38 00 42 00                   mov r8=r14;;
  6c:   10 02 aa 00                         mov.i ar.pfs=r33
  70:   00 00 00 00 01 00       [MII]       nop.m 0x0
  76:   00 00 05 80 03 80                   mov b0=r32
  7c:   01 10 01 84                         mov r12=r34
  80:   1d 00 00 00 01 00       [MFB]       nop.m 0x0
  86:   00 00 00 02 00 80                   nop.f 0x0
  8c:   08 00 84 00                         br.ret.sptk.many b0;;

Note the movl at offset 36 should be 0xffffffff1194d810 instead of 0x1194d810.

As mentioned before, this only occurs with no optimization, i.e. -O1 and above
work fine.  It also occurs with all previous versions tested - 3.2.x, 2.96, etc.
Tested on Itanium & Itanium2 boxes running Red Hat Advanced Server 2.1.