[Bug target/37010] -Os passes __m128 on stack with wrong alignment

["hjl dot tools at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #4 from hjl dot tools at gmail dot com  2008-08-03 20:11 -------
A run-time testcase:

bash-3.2$ cat y.c
/* PR middle-end/37010 */
/* { dg-do run { target { { i?86-*-* x86_64-*-* } && ilp32 } } } */
/* { dg-options "-msse2" } */

typedef __PTRDIFF_TYPE__ ptrdiff_t;
extern void abort (void);

int
__attribute__ ((noinline))
check_int (int *i, int align)
{
  *i = 20;
  if ((((ptrdiff_t) i) & (align - 1)) != 0)
    {
      abort ();
    }
  return *i;
}
typedef float __m128 __attribute__ ((__vector_size__ (16), __may_alias__));

typedef int aligned __attribute__((aligned(16)));

__m128 r;

void
__attribute__ ((noinline))
foo (__m128 x, __m128 y ,__m128 z ,__m128 a, int size)
{
  aligned i;

  if (check_int (&i, __alignof__(i)) != i)
    abort ();
  r = a;
}

int
main (void)
{
  __m128 x = { 1.0 };

  foo (x, x, x, x, 5);

  if (__builtin_memcmp (&r, &x, sizeof (r)))
    abort ();

  return 0;
}
bash-3.2$ make y
/export/build/gnu/gcc-avx/build-x86_64-linux/gcc/xgcc
-B/export/build/gnu/gcc-avx/build-x86_64-linux/gcc/ -m32 -msse2 -DDEBUG -Os
-mpreferred-stack-boundary=2    y.c   -o y
bash-3.2$ ./y
Segmentation fault
bash-3.2$ /export/build/gnu/gcc-avx/build-x86_64-linux/gcc/xgcc
-B/export/build/gnu/gcc-avx/build-x86_64-linux/gcc/ -m32 -msse2 -DDEBUG -O
-mpreferred-stack-boundary=2    y.c   -o y
bash-3.2$ ./y
bash-3.2$ 


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37010