Re: [patch 06/10] Immediate Value - i386 Optimization

[Jeremy Fitzhardinge]

Chuck Ebbert wrote:
> On 07/03/2007 04:18 PM, H. Peter Anvin wrote:
>   
> > One could, though, use an indirect jump to achieve, if not as good, at
> > least most of the effect:
> >
> > 	movl	$<patchable>,<reg>
> > 	jmp	*<reg>
> >
> >     
>
> Yeah, but there's this GCC bug:
>
> 	http://gcc.gnu.org/bugzilla/show_bug.cgi?id=22448
>
> You can't even dereference labels in an ASM statement.

I was told in absolute terms that any use of &&label other than to pass 
it to goto was not supported, and would not be supported.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29305

Seems that passing to an asm() falls into the same class of problem I 
had.  I think the underlying problem is that if the code containing the 
label is in an inlined function or unrolled loop, the reference can't be 
resolved properly anyway.

   J
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