register elimination problem

[Richard Henderson]

On Sun, Dec 16, 2001 at 12:23:55AM +0100, Roman Zippel wrote:
> There can now be a problem with targets using the second version. It can
> happen that the arg pointer can't be eliminated with the stack pointer,
> but the frame pointer can. The result is that the frame pointer isn't
> initialized, but arguments are accessed through it.

This really sounds like

2001-11-20  Brad Kaiser  <bkaiser@acelink.net>

        * reload1.c (elimination_effects): Use function_invariant_p
        instead of CONSTANT_P when considering register equivalences.

but maybe you've got a different case.  Test case?
What target -- m68k doesn't seem to define ELIMINABLE_REGS,
which seems surprising...


r~