[m-dev.] for review: improved low-level debugging messages

[Zoltan Somogyi]

> >  incr_hp_debug_msg(Word val, const Word *addr)
> >  {
> >  #ifdef CONSERVATIVE_GC
> > -	printf("allocated %ld words at 0x%p\n", (long) (Integer) val, addr);
> > +	printf("allocated %ld words at %p\n", (long) (Integer) val, addr);
> 
> Both the old code and the new code are buggy, because there is no guarantee
> that (long) is the same size as `void *'.

You seem to be confused. The cast is on the size of the new cell, not
the pointer.

> >  	for (i = 1; &MR_based_framevar(fr,i) > MR_prevfr_slot(fr); i++) {
> > -		printf("\t framevar(%d)  %ld 0x%lx\n",
> > +		printf("\t framevar(%d)  %ld %lx\n",
> >  			i, (long) (Integer) MR_based_framevar(fr,i),
> >  			(unsigned long) MR_based_framevar(fr,i));
> >  	}
> 
> What's the rationale for this change?
> The log message says
> 
>  	Improve the facilities for printing pointers into the det and nondet
>  	stacks for diagnostic purposes.
> 
> but why is removing the "0x" here an improvement?

I was removing the 0x from in front of %p, since the platforms we are using
now, unlike the SGIs, print the 0x for %p, and I don't want to look at
addresses that start with 0x0x. The change above was overzealous removal of
0xs; I will undo it.

> > +print_detstackptr(FILE *fp, const Word *s)
> 
> These new functions should get an `MR_' prefix.
> 
> > +++ mercury_misc.h	1999/03/16 01:19:16
> > +extern	void	printdetstack(const Word *s);
> > +extern	void	printdetstackptr(const Word *s);
> > +extern	void	print_detstackptr(FILE *fp, const Word *s);
> > +extern	void	printnondstack(const Word *s);
> > +extern	void	printnondstackptr(const Word *s);
> > +extern	void	print_nondstackptr(FILE *fp, const Word *s);
> 
> Likewise.

Ah, but some of those are not new functions; their declarations have
just been grouped together.

I will add the prefix for the new functions. The old ones require changes
elsewhere, which will probably conflict with Tyson's changes in progress,
so I will add the prefix for them later. We should have a great renaming
of everything in the runtime anyway.

Zoltan.