use of extended asm on ppc for long long data types

[Kumar Gala]

On Apr 6, 2005, at 2:11 PM, David Edelsohn wrote:

> >>>>> Kumar Gala writes:
>
> Kumar> Is there anyway to specify a long long data type as a 
> constraint to
> Kumar> extended asm for powerpc32.  If so, how does one specify the 
> registers
> Kumar> that would have the upper and lower bits
>
>         The rs6000.md machine description has examples of patterns
>  implementing 64-bit (DImode) operations in 32-bit mode.  The 
> constraint is
>  a normal "r" or "b" GPR constraint.  GCC allocates pairs of 
> consecutive
>  registers to hold the 64-bit value in 32-bit mode.
>
>         When operating in big-endian, the MSB is in the first register 
> and
>  the LSB is the second register (R+1); in little-endian mode, the two
>  registers are reversed.  The PowerPC port defines a special 
> print_operand
>  modifier %L to refer to R+1, e.g., for operand 0, one would write 
> assembly
> code referring to %0 and %L0.

This is great, can I beg of you to update the gcc docs to include this 
note for the rs6000 extended asm section.

thanks

- kumar