memory region documentation

[Eli Zaretskii]

> From: jtc@redback.com (J.T. Conklin)
> Date: 30 Nov 2000 12:08:53 -0800
> 
> The reason I didn't think it fit in the Data chapter was the not yet
> implemented breakpoint attribute.  GDB needs to insert breakpoints for
> step, next, continue, etc.; but it can't do it if the memory region is
> protected (ie, image is running out of ROM, FLASH, etc.).  So there 
> needs to be a mechanism to tell GDB to use hardware breakpoints for
> those internal breakpoints.  This part of the feature isn't really
> "data" related.

That's true, but I don't think this is a reason grave enough to make
this a separate chapter.

I think the right question is: would a user reasonably expect this
feature be described under Data?  If so, we can put it there.  We can
also add a short explanation in the section about breakpoints saying
that in the case of read-only code memory, they need to use memory
regions first, with a cross-reference to the stuff you've written.