[PATCH] Fold zero extensions into bit-wise ANDs

[Richard Henderson]

On Mon, Apr 15, 2002 at 06:31:55PM -0600, Roger Sayle wrote:
> long long foo(unsigned char bar)
> {
>   return bar & 0x24;
> }
> 
> with the current mainline CVS we'd generate:
> 
> foo:	movzbl	4(%esp), %ecx
> 	xorl	%edx, %edx
> 	andb	$36, %cl
> 	movzbl	%cl, %eax
> 	ret
> 
> with my patch applied it now generates
> 
> foo:	movzbl	4(%esp), %eax
> 	andl	$36, %eax
> 	cltd
> 	ret

Now that is interesting, and certainly not what I expected.
The patch is ok for mainline then.


r~