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
  30 /* Types that describe the various builtin registers.  */
  31
  32 static struct type *builtin_type_frame_reg;
  33
  34 /* Constructors for those types.  */
  35
  36 static void
  37 build_builtin_type_frame_reg (void)
  38 {
  39   /* $frame.  */
  40   if (builtin_type_frame_reg == NULL)
  41     {
  42 #if 0
  43       struct frame
  44       {
  45         void *base;
  46       };
  47 #endif
  48       builtin_type_frame_reg = init_composite_type ("frame", TYPE_CODE_STRUCT);
  49       append_composite_type_field (builtin_type_frame_reg, "base",
  50                                    builtin_type_void_data_ptr);
  51     }
  52 }
  53
  54 static struct value *
  55 value_of_builtin_frame_reg (struct frame_info *frame)
  56 {
  57   struct value *val;
  58   char *buf;
  59   build_builtin_type_frame_reg ();
  60   val = allocate_value (builtin_type_frame_reg);
  61   VALUE_LVAL (val) = not_lval;
  62   buf = VALUE_CONTENTS_RAW (val);
  63   memset (buf, TYPE_LENGTH (VALUE_TYPE (val)), 0);
  64   /* frame.base.  */
  65   if (frame != NULL)
  66     ADDRESS_TO_POINTER (builtin_type_void_data_ptr, buf, frame->frame);
  67   buf += TYPE_LENGTH (builtin_type_void_data_ptr);
  68   /* frame.XXX.  */
  69   return val;
  70 }
  71
  72 static struct value *
  73 value_of_builtin_frame_fp_reg (struct frame_info *frame)
  74 {
  75 #ifdef FP_REGNUM
  76   if (FP_REGNUM >= 0)
  77     return value_of_register (FP_REGNUM, frame);
  78 #endif
  79   {
  80     struct value *val = allocate_value (builtin_type_void_data_ptr);
  81     char *buf = VALUE_CONTENTS_RAW (val);
  82     if (frame == NULL)
  83       memset (buf, TYPE_LENGTH (VALUE_TYPE (val)), 0);
  84     else
  85       ADDRESS_TO_POINTER (builtin_type_void_data_ptr, buf, frame->frame);
  86     return val;
  87   }
  88 }
  89
  90 static struct value *
  91 value_of_builtin_frame_pc_reg (struct frame_info *frame)
  92 {
  93 #ifdef PC_REGNUM
  94   if (PC_REGNUM >= 0)
  95     return value_of_register (PC_REGNUM, frame);
  96 #endif
  97   {
  98     struct value *val = allocate_value (builtin_type_void_data_ptr);
  99     char *buf = VALUE_CONTENTS_RAW (val);
 100     if (frame == NULL)
 101       memset (buf, TYPE_LENGTH (VALUE_TYPE (val)), 0);
 102     else
 103       ADDRESS_TO_POINTER (builtin_type_void_data_ptr, buf, frame->pc);
 104     return val;
 105   }
 106 }
 107
 108 static struct value *
 109 value_of_builtin_frame_sp_reg (struct frame_info *frame)
 110 {
 111 #ifdef SP_REGNUM
 112   if (SP_REGNUM >= 0)
 113     return value_of_register (SP_REGNUM, frame);
 114 #endif
 115   error ("Standard register ``$sp'' is not available for this target");
 116 }
 117
 118 static struct value *
 119 value_of_builtin_frame_ps_reg (struct frame_info *frame)
 120 {
 121 #ifdef PS_REGNUM
 122   if (PS_REGNUM >= 0)
 123     return value_of_register (PS_REGNUM, frame);
 124 #endif
 125   error ("Standard register ``$ps'' is not available for this target");
 126 }
 127
 128 void
 129 _initialize_frame_reg (void)
 130 {
 131   /* FIXME: cagney/2002-02-08: At present the local builtin types
 132      can't be initialized using _initialize*() or gdbarch.  Due mainly
 133      to non-multi-arch targets, GDB initializes things piece meal and,
 134      as a consequence can leave these types NULL.  */
 135   REGISTER_GDBARCH_SWAP (builtin_type_frame_reg);
 136
 137   /* Frame based $fp, $pc, $sp and $ps.  These only come into play
 138      when the target does not define its own version of these
 139      registers.  */
 140   add_builtin_reg ("fp", value_of_builtin_frame_fp_reg);
 141   add_builtin_reg ("pc", value_of_builtin_frame_pc_reg);
 142   add_builtin_reg ("sp", value_of_builtin_frame_sp_reg);
 143   add_builtin_reg ("ps", value_of_builtin_frame_ps_reg);
 144
 145   /* NOTE: cagney/2002-04-05: For moment leave the $frame / $gdbframe
 146      / $gdb.frame disabled.  It isn't yet clear which of the many
 147      options is the best.  */
 148   if (0)
 149     add_builtin_reg ("frame", value_of_builtin_frame_reg);
 150 }