[RFA patch] PR18749: epilogue not tracked in dwarf2 unwind-info

[Daniel Jacobowitz]

On Mon, Jun 12, 2006 at 11:02:38PM +0200, Michael Matz wrote:
> If you are saying that currently it could happen that CFA-(1) != CFA-(2), 
> then this non-epilogue instruction would need to have an effect on the 
> CFA, without actually producing code (or the next epilogue insn must not 
> produce code), as otherwise you would have the same runtime effect twice 
> (once from the non-epilogue insn, once from the epilogue compensation).  
> Can this happen?

I have no idea :-)  I'm way out in hypothetical cases here, don't worry
about it overmuch.

But here's an example using conditional execution:

  popeq lr
  sub sp, #64
  addeq sp, #68
  bxeq lr

Of course it'd be a somewhat silly thing to generate.

-- 
Daniel Jacobowitz
CodeSourcery