Re: PA-RISC bug in gas

[Nick Clifton]

Hi Dan,

> Hi - I'm trying to use gas 2.15 on PA-RISC, and I want to issue an ldcws 
> instruction like:
>
>     ldcws,co 0(%r20), %r19
>
> which is accepted by the HP assembler, but gas barfs with:
>
>    Error: Invalid Short Load/Store Completer.
>
> gas apparently doesn't like the cache control hint completor, which is 
> critical for semaphore performance on PA-RISC. I've tried every 
> reasonable combination of characters for the completer that I can think 
> of, and nothing seems to work.

I passed this question and your proposed patch onto the HPPA binutils 
port maintainer.  This is what he had to say about it:

: One problem is you are mixing PA 1.x and 2.0 assembler semantics.
: The co completer is a PA 2.0 feature.  PA 1.x processors don't
: support this completer.  The PA 2.0 semantics is ldcw,co.  I guess
: the HP assembler accepts ldcws as a synonym for ldcw when generating
: PA 2.0 code.

: I suspect that if Dan changes ldcws to ldcw and specifies .level
: correctly, the assembler will accept the co completer.

I hope that this helps.

Cheers
  Nick