Re: [commit] mn10300: Register a dwarf2_reg_to_regnum function

[Mark Kettenis <mark.kettenis@xs4all.nl>]

> Date: Fri, 2 Sep 2005 18:09:15 -0700
> From: Kevin Buettner <kevinb@redhat.com>
> 
> This code used to be in the old version of mn10300-tdep.c.  It's absence
> from the current version of mn10300-tdep.c is an oversight.  When I asked
> Michael Snyder about it a while back, he asked me to reinstate it.  So
> here it is...
> 
> 	* mn10300-tdep.c (mn10300_dwarf2_reg_to_regnum): New function.
> 	(mn10300_gdbarch_init): Register mn10300_dwarf2_reg_to_regnum().
> 
> Index: mn10300-tdep.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/mn10300-tdep.c,v
> retrieving revision 1.128
> diff -u -p -r1.128 mn10300-tdep.c
> --- mn10300-tdep.c	3 Sep 2005 00:49:06 -0000	1.128
> +++ mn10300-tdep.c	3 Sep 2005 01:02:48 -0000
> @@ -937,6 +937,37 @@ mn10300_push_dummy_call (struct gdbarch 
>    return sp;
>  }
>  
> +/* If DWARF2 is a register number appearing in Dwarf2 debug info, then
> +   mn10300_dwarf2_reg_to_regnum (DWARF2) is the corresponding GDB
> +   register number.  Why don't Dwarf2 and GDB use the same numbering?
> +   Who knows?  But since people have object files lying around with
> +   the existing Dwarf2 numbering, and other people have written stubs
> +   to work with the existing GDB, neither of them can change.  So we
> +   just have to cope.  */
> +static int
> +mn10300_dwarf2_reg_to_regnum (int dwarf2)
> +{
> +  /* This table is supposed to be shaped like the REGISTER_NAMES
> +     initializer in gcc/config/mn10300/mn10300.h.  Registers which
> +     appear in GCC's numbering, but have no counterpart in GDB's
> +     world, are marked with a -1.  */
> +  static int dwarf2_to_gdb[] = {
> +    0,  1,  2,  3,  4,  5,  6,  7, -1, 8,
> +    15, 16, 17, 18, 19, 20, 21, 22,
> +    32, 33, 34, 35, 36, 37, 38, 39,
> +    40, 41, 42, 43, 44, 45, 46, 47,
> +    48, 49, 50, 51, 52, 53, 54, 55,
> +    56, 57, 58, 59, 60, 61, 62, 63
> +  };
> +
> +  if (dwarf2 < 0
> +      || dwarf2 >= (sizeof (dwarf2_to_gdb) / sizeof (dwarf2_to_gdb[0]))
> +      || dwarf2_to_gdb[dwarf2] == -1)
> +    internal_error (__FILE__, __LINE__,
> +                    "bogus register number in debug info: %d", dwarf2);
> +
> +  return dwarf2_to_gdb[dwarf2];
> +}

Could you use ARRAY_SIZE here?  And that string should be i18n'd.  or
perhaps it's better to use gdb_assert(); saves the translators some
work ;-).

Hmm, isn't an internal error actually inappropriate here?  The
condition could be triggered by bogus debug info, couldn't it?  That
should be handled more graceful.

Mark