Re: gas fix for ia64 target

[Nick Clifton <nickc at cambridge dot redhat dot com>]

Hi David,

> Unrelated but trivial: the patch adds documentation for the 
> -mconstant-gp and -mauto-pic command-line options.

Note - although these options are now documented in the executable
they are still missing from the gas/doc directory... [hint hint]

> 2002-02-20  David Mosberger  <davidm@hpl.hp.com>
> 
> 	* config/tc-ia64.c (dot_restore): Issue error message of epilogue
> 	count exceeds prologue count.
> 	(md_show_usage): Describe -mconstant-gp and -mauto-pic.
> 	(unwind.label_prologue_count): New member.
> 
> 	Based on a patch by Hans Boehm <hboehm@hpl.hp.com>:
> 
> 	(get_saved_prologue_count): New function.
> 	(save_prologue_count): New function.
> 	(free_saved_prologue_count): New function.
> 	(dot_label_state): Record state label by calling save_prologue_count().
> 	(dot_copy_state): Restore prologue count by calling
> 	get_saved_prologue_count().
> 	(generate_unwind_image): Free up list of saved prologue
> 	counts by calling free_saved_prologue_counts().

Approved * applied (mainline & branch).

Note - your patch had a bug which I fixed whilst applying:

> +static void
> +save_prologue_count (lbl, count)
> +     unsigned long lbl;
> +     unsigned int count;
> +{
> +  label_prologue_count *lpc = unwind.saved_prologue_counts;
> +  while (lpc != 0 && lpc->label_number != lbl)
> +    lpc = lpc->next;
> +  if (lpc != 0)
> +    lpc->prologue_count = count;
> +  else
> +    {
> +      label_prologue_count * new_lpc = xmalloc (sizeof (label_prologue_count));
> +      new_lpc->next = lpc;
> +      new_lpc->label_number = lbl;
> +      new_lpc->prologue_count = count;
> +      unwind.saved_prologue_counts = new_lpc;
> +    }
> +}

The assignment of 'lpc' to the 'next' field of the newly created
'new_lpc' structure means that any current elements on the
unwind.saved_prologue_counts list will be discarded.  I assumed that
you meant to write:

         new_lpc->next = unwind.saved_prologue_counts;

Cheers
        Nick