https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70087
David Malcolm <dmalcolm at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |dmalcolm at gcc dot gnu.org
--- Comment #3 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
FWIW, doing it as a switch leads to a branch also:
int baz ()
{
switch (at)
{
case 2:
case 4:
case 7:
return 1;
default:
return 0;
}
}
baz:
.LFB2:
.cfi_startproc
movl at(%rip), %ecx
xorl %eax, %eax
cmpl $7, %ecx
ja .L7
movl $1, %eax
salq %cl, %rax
testb $-108, %al
setne %al
.L7:
movzbl %al, %eax
ret
.cfi_endproc
where switchconv printed "expanding as bit test is preferable".
