On Thu, 24 May 2001, Ignatios Souvatzis wrote:

> On Thu, May 24, 2001 at 11:22:51AM +0100, Richard Earnshaw wrote:
> > No, because by the time the fault happens you no-longer know where the
> > faulty instruction is.
> >
> > Remember the problem occurs when
> >
> > 1) The last instruction in the page is ldr or ldm that writes the PC
> > 2) The next page is not mapped
>
> Evil idea: "always map the next page when the last longword is a ldr or ldm
> that writes the PC."
>
> Of course, an option.
> Wasn't somebody rewriting the pmap?

	I think the only clean guaranteed way to avoid the problem would
	be to have a compiler option to use the instructions to load the
	individual registers. A more complex variation would be to handle
	it in the linker based on the alignment of the instruction insert
	a nop to shift the ldm to the next page.

	Of course given the small number of machines with that hardware
	it may be difficult to get it back into the gcc mainline.

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