[Bug middle-end/27567] [4.0/4.1 Regression] __builtin_memcpy generates redundant stores/moves.
pluto at agmk dot net
gcc-bugzilla@gcc.gnu.org
Wed Feb 14 22:24:00 GMT 2007
------- Comment #8 from pluto at agmk dot net 2007-02-14 22:24 -------
still bad :/
float convert( unsigned in )
{
float f;
__builtin_memcpy( &f, &in, sizeof( in ) );
return f;
}
unsigned short load( void* p )
{
unsigned short v;
__builtin_memcpy( &v, p, sizeof( v ) );
return v;
}
convert:
movl %edi, -4(%rsp)
movss -4(%rsp), %xmm1
movaps %xmm1, %xmm0
ret
load:
movzwl (%rdi), %eax
movw %ax, -2(%rsp)
movzwl %ax, %eax
ret
gcc-42 (20070207)
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27567
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