------- Comment #1 from dennis at conus dot info 2010-05-24 13:30 -------
The code 4.4.1 x86 generating (with -O3 option) for bswap() function I
mentioned earlier is strange too:
; bswap(unsigned int)
public _Z5bswapj
_Z5bswapj proc near
var_4 = dword ptr -4
arg_0 = dword ptr 8
push ebp
mov ebp, esp
sub esp, 10h
mov eax, [ebp+arg_0]
mov edx, eax
sar edx, 18h
mov byte ptr [ebp+var_4], dl
mov edx, eax
shr edx, 10h
mov byte ptr [ebp+var_4+1], dl
movsx edx, ah
mov byte ptr [ebp+var_4+3], al
mov eax, [ebp+var_4] ; returning var_4
mov byte ptr [ebp+var_4+2], dl ; set last byte to var_4
leave
retn
_Z5bswapj endp
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44260
