[PATCH][SH] CFI directives patch

[Richard Henderson]

On 05/23/2012 04:57 AM, Chung-Lin Tang wrote:
> With a stack adjustment in the call delay slot, the unwinder will be
> 4-bytes off the correct adjustment when crossing that frame; this
> probably is an issue of how program counters map to FDEs (<  vs<=).
>
> CCing Richard Henderson here, who's probably the one to answer this.
> Richard, I remember seeing related discussion in the archives on this
> issue, as well as comments in the current GCC dwarf2cfi.c:scan_trace()
> code, can you confirm?

FWIW, pushing the unwind data from the delay slot to before the call
is exactly what gcc itself does.  Though, really, we try very hard to
*not* place unwind-related insn in delay slots.


r~