http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17994
Anitha Boyapati <anitha.boyapati at atmel dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |anitha.boyapati at atmel
| |dot com
--- Comment #4 from Anitha Boyapati <anitha.boyapati at atmel dot com>
2010-12-29 07:05:09 UTC ---
(In reply to comment #1)
> 3.) There seems to be only one little part missing in order to add the call
> stack information as well: The back-end needs to provide the information at
> which memory address the debugger could localize the return address. This
> would
> require to implement the target hook INCOMING_RETURN_ADDR_RTX and use the
> RTX_FRAME_RELATED_P predicate for all of the prologue/epilogue insn.
I know this has been delayed for too long. But I thought a small update would
perhaps help.
Looks like to get call-stack debug info, all we require to do is define
INCOMING_RETURN_ADDR_RTX. In AVR, since the return address is pushed onto the
stack for every call instruction, the above hook is defined to
avr_incoming_return_addr_rtx() of dwarf2out.c:
rtx
avr_incoming_return_addr_rtx(void) {
return gen_rtx_MEM (HImode, stack_pointer_rtx);
}
And this gives an ICE in dwarf2out_frame_debug_expr(). Modifying the above
function to pre decrement the stack pointer gives an ICE in
initial_return_save()
gen_rtx_MEM (HImode, gen_rtx_PRE_DEC (HImode, stack_pointer_rtx))
