[PATCH][PowerPC] Fix BlockAddress access on ppc64

[Anton Blanchard]

Hi Uli,

> Anton noticed that code using the GCC extension to take the address
> of a block label (which is used e.g. in Linux kernel code):
> 
>   __label__ here;
> here:
>   printf ("current address: %p\n", &&here);
> 
> is miscompiled on ppc64 since it directly accesses the label value
> via @l / @ha, which fails if the code is linked to an address > 2GB.
> 
> The attached patch fixes this by loading such values from the TOC, as
> is done for any other global symbol.

Thanks! I verified this fixed the issue for me.

Anton