gdb/std-regs.c

   1 /* Builtin frame register, for GDB, the GNU debugger.
   2
   3    Copyright 2002 Free Software Foundation, Inc.
   4
   5    Contributed by Red Hat.
   6
   7    This file is part of GDB.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 59 Temple Place - Suite 330,
  22    Boston, MA 02111-1307, USA.  */
  23
  24 #include "defs.h"
  25 #include "builtin-regs.h"
  26 #include "frame.h"
  27 #include "gdbtypes.h"
  28 #include "value.h"
  29 #include "gdb_string.h"
  30
  31 /* Types that describe the various builtin registers.  */
  32
  33 static struct type *builtin_type_frame_reg;
  34
  35 /* Constructors for those types.  */
  36
  37 static void
  38 build_builtin_type_frame_reg (void)
  39 {
  40   /* $frame.  */
  41   if (builtin_type_frame_reg == NULL)
  42     {
  43 #if 0
  44       struct frame
  45       {
  46         void *base;
  47       };
  48 #endif
  49       builtin_type_frame_reg = init_composite_type ("frame", TYPE_CODE_STRUCT);
  50       append_composite_type_field (builtin_type_frame_reg, "base",
  51                                    builtin_type_void_data_ptr);
  52     }
  53 }
  54
  55 static struct value *
  56 value_of_builtin_frame_reg (struct frame_info *frame)
  57 {
  58   struct value *val;
  59   char *buf;
  60   build_builtin_type_frame_reg ();
  61   val = allocate_value (builtin_type_frame_reg);
  62   VALUE_LVAL (val) = not_lval;
  63   buf = VALUE_CONTENTS_RAW (val);
  64   memset (buf, TYPE_LENGTH (VALUE_TYPE (val)), 0);
  65   /* frame.base.  */
  66   if (frame != NULL)
  67     ADDRESS_TO_POINTER (builtin_type_void_data_ptr, buf, frame->frame);
  68   buf += TYPE_LENGTH (builtin_type_void_data_ptr);
  69   /* frame.XXX.  */
  70   return val;
  71 }
  72
  73 static struct value *
  74 value_of_builtin_frame_fp_reg (struct frame_info *frame)
  75 {
  76 #ifdef FP_REGNUM
  77   if (FP_REGNUM >= 0)
  78     return value_of_register (FP_REGNUM, frame);
  79 #endif
  80   {
  81     struct value *val = allocate_value (builtin_type_void_data_ptr);
  82     char *buf = VALUE_CONTENTS_RAW (val);
  83     if (frame == NULL)
  84       memset (buf, TYPE_LENGTH (VALUE_TYPE (val)), 0);
  85     else
  86       ADDRESS_TO_POINTER (builtin_type_void_data_ptr, buf, frame->frame);
  87     return val;
  88   }
  89 }
  90
  91 static struct value *
  92 value_of_builtin_frame_pc_reg (struct frame_info *frame)
  93 {
  94 #ifdef PC_REGNUM
  95   if (PC_REGNUM >= 0)
  96     return value_of_register (PC_REGNUM, frame);
  97 #endif
  98   {
  99     struct value *val = allocate_value (builtin_type_void_data_ptr);
 100     char *buf = VALUE_CONTENTS_RAW (val);
 101     if (frame == NULL)
 102       memset (buf, TYPE_LENGTH (VALUE_TYPE (val)), 0);
 103     else
 104       ADDRESS_TO_POINTER (builtin_type_void_data_ptr, buf, frame->pc);
 105     return val;
 106   }
 107 }
 108
 109 static struct value *
 110 value_of_builtin_frame_sp_reg (struct frame_info *frame)
 111 {
 112 #ifdef SP_REGNUM
 113   if (SP_REGNUM >= 0)
 114     return value_of_register (SP_REGNUM, frame);
 115 #endif
 116   error ("Standard register ``$sp'' is not available for this target");
 117 }
 118
 119 static struct value *
 120 value_of_builtin_frame_ps_reg (struct frame_info *frame)
 121 {
 122 #ifdef PS_REGNUM
 123   if (PS_REGNUM >= 0)
 124     return value_of_register (PS_REGNUM, frame);
 125 #endif
 126   error ("Standard register ``$ps'' is not available for this target");
 127 }
 128
 129 void
 130 _initialize_frame_reg (void)
 131 {
 132   /* FIXME: cagney/2002-02-08: At present the local builtin types
 133      can't be initialized using _initialize*() or gdbarch.  Due mainly
 134      to non-multi-arch targets, GDB initializes things piece meal and,
 135      as a consequence can leave these types NULL.  */
 136   REGISTER_GDBARCH_SWAP (builtin_type_frame_reg);
 137
 138   /* Frame based $fp, $pc, $sp and $ps.  These only come into play
 139      when the target does not define its own version of these
 140      registers.  */
 141   add_builtin_reg ("fp", value_of_builtin_frame_fp_reg);
 142   add_builtin_reg ("pc", value_of_builtin_frame_pc_reg);
 143   add_builtin_reg ("sp", value_of_builtin_frame_sp_reg);
 144   add_builtin_reg ("ps", value_of_builtin_frame_ps_reg);
 145
 146   /* NOTE: cagney/2002-04-05: For moment leave the $frame / $gdbframe
 147      / $gdb.frame disabled.  It isn't yet clear which of the many
 148      options is the best.  */
 149   if (0)
 150     add_builtin_reg ("frame", value_of_builtin_frame_reg);
 151 }