------- Comment #2 from jakub at gcc dot gnu dot org 2010-07-23 07:42 -------
This isn't a mere debug info quality regression, a movl $2, (%esp) is now
optimized away, eventhough it is needed by asm volatile following it.
Here is a testcase that at -O1 -m32 now fails at runtime, while it worked well
before:
/* PR debug/36728 */
/* { dg-do run } */
/* { dg-options "-O1" } */
int __attribute__((noinline))
foo (int arg1, int arg2, int arg3, int arg4, int arg5, int arg6, int arg7)
{
char x[30];
int __attribute__ ((aligned(32))) y;
y = 2;
asm volatile ("cmpl $2, %0; je 1f; hlt; 1:" : "=m" (y) : "m" (y));
x[0] = 25;
asm volatile ("" : "=m" (x[0]) : "m" (x[0]));
return y;
}
int
main ()
{
int l = 0;
asm volatile ("" : "=r" (l) : "0" (l));
foo (l + 1, l + 2, l + 3, l + 4, l + 5, l + 6, l + 30);
return 0;
}
The diff is:
@@ -7,7 +7,6 @@ foo:
movl %esp, %ebp
andl $-32, %esp
subl $64, %esp
- movl $2, (%esp)
#APP
# 12 "PP.c" 1
cmpl $2, (%esp); je 1f; hlt; 1:
--
jakub at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever Confirmed|0 |1
Last reconfirmed|0000-00-00 00:00:00 |2010-07-23 07:42:27
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45035
