DWARF2 offset for local variables

[BELBACHIR Selim]

Hi,

I'm (still) working on a new gcc-4.5.2 backend for a private processor.
Today i'm concerned about the debug mode using DWARF2.

Here is my problem:
When I use GDB on a executable compiled with -g option I notice that the 
addresses of all my local variables are wrong.
I read gccint doc and tried to use DEBUGGER_AUTO_OFFSET(X) and 
DEBUGGER_ARG_OFFSET(OFFSET, X) but I noticed (thanks to printf) that they were 
never called for DWARF2. (I saw afterward that dwarf2out.c did not use these 
macros)

My stack frame is organized as follow :

Hi mem Address |                   |
               +-------------------+ <= $SP before prologue
               |                   |
               |     Reg save      |
               |                   |
               +-------------------+
               |                   |
               |  Locals / Temps   |
               |                   |
               +-------------------+
               |                   |
               |    Args Block     |
               |                   |
               +-------------------+ <= $SP after prologue
Lo mem Address |                   |
  

With 

#define STACK_GROWS_DOWNWARD 1
#define FRAME_POINTER_CFA_OFFSET(FNDECL) 0
#define STARTING_FRAME_OFFSET crtl->outgoing_args_size
#define FIRST_PARM_OFFSET(FUNDECL) 0
#define DWARF2_DEBUGGING_INFO
#define PREFERRED_DEBUGGING_TYPE DWARF2_DEBUG  
#define ELIMINABLE_REGS \
  {{HARD_FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM}, \
   {FRAME_POINTER_REGNUM, STACK_POINTER_REGNUM}, \
   {FRAME_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM}, \
   {ARG_POINTER_REGNUM, STACK_POINTER_REGNUM}, \
   {ARG_POINTER_REGNUM, HARD_FRAME_POINTER_REGNUM}, \
  }
#define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \
  (OFFSET) = my_initial_elimination_offset ((FROM), (TO))


HOST_WIDE_INT my_initial_elimination_offset (int from, int to ATTRIBUTE_UNUSED)
{
  HOST_WIDE_INT offset;
  switch (from)
  {
  case HARD_FRAME_POINTER_REGNUM:
    offset = 0;
    break;
  case FRAME_POINTER_REGNUM:
    offset = 0;
    break;
  case ARG_POINTER_REGNUM:
    offset = my_stack_frame_size();
    break;
  default:
    gcc_unreachable ();
  }
  return offset;
}


How can I express an offset for local variables in DWARF2 for GDB ?


Regards,

        Selim Belbachir