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[Bug target/52415] memcpy to local variable generates unnecessary stack frame for armv7


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52415

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

           What    |Removed                     |Added
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                 CC|                            |jakub at gcc dot gnu.org

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-02-28 12:29:14 UTC ---
But to answer your question, how you can assert it is properly aligned, in gcc
4.7.0 you can write:
  __builtin_memcpy (&i, __builtin_assume_aligned (p, sizeof *p), sizeof i);
which will assert that p is sizeof (float) bytes aligned and then you get code
without the stack frame.  Or you can use a union instead of memcpy:
  union U { float f; int i; } u;
  u.f = *p;
  return u.i;


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