http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25290
Marc Glisse <glisse at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |glisse at gcc dot gnu.org
--- Comment #6 from Marc Glisse <glisse at gcc dot gnu.org> ---
I assume it would help with this?
int f(int a,int b){
return (a<0)&(b<0);
}
int g(int a,int b){
return (a<0)?(b<0):0;
}
int h(int a,int b){
if (a<0) return (b<0);
return 0;
}
where (on x86) we turn g into f, but we don't notice that h is the same. In
asm, that is:
movl %esi, %eax
andl %edi, %eax
shrl $31, %eax
((a<0)&(b<0) is later optimized to (a&b)<0)
vs
shrl $31, %esi
xorl %eax, %eax
testl %edi, %edi
cmovs %esi, %eax
