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 "user-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, 0, TYPE_LENGTH (VALUE_TYPE (val))); 65 /* frame.base. */ 66 if (frame != NULL) 67 ADDRESS_TO_POINTER (builtin_type_void_data_ptr, buf, 68 get_frame_base (frame)); 69 buf += TYPE_LENGTH (builtin_type_void_data_ptr); 70 /* frame.XXX. */ 71 return val; 72 } 73 74 static struct value * 75 value_of_builtin_frame_fp_reg (struct frame_info *frame) 76 { 77 if (DEPRECATED_FP_REGNUM >= 0) 78 /* NOTE: cagney/2003-04-24: Since the mere presence of "fp" in the 79 register name table overrides this built-in $fp register, there 80 is no real reason for this DEPRECATED_FP_REGNUM trickery here. 81 An architecture wanting to implement "$fp" as alias for a raw 82 register can do so by adding "fp" to register name table (mind 83 you, doing this is probably a dangerous thing). */ 84 return value_of_register (DEPRECATED_FP_REGNUM, frame); 85 else 86 { 87 struct value *val = allocate_value (builtin_type_void_data_ptr); 88 char *buf = VALUE_CONTENTS_RAW (val); 89 if (frame == NULL) 90 memset (buf, 0, TYPE_LENGTH (VALUE_TYPE (val))); 91 else 92 ADDRESS_TO_POINTER (builtin_type_void_data_ptr, buf, 93 get_frame_base_address (frame)); 94 return val; 95 } 96 } 97 98 static struct value * 99 value_of_builtin_frame_pc_reg (struct frame_info *frame) 100 { 101 if (PC_REGNUM >= 0) 102 return value_of_register (PC_REGNUM, frame); 103 else 104 { 105 struct value *val = allocate_value (builtin_type_void_data_ptr); 106 char *buf = VALUE_CONTENTS_RAW (val); 107 if (frame == NULL) 108 memset (buf, 0, TYPE_LENGTH (VALUE_TYPE (val))); 109 else 110 ADDRESS_TO_POINTER (builtin_type_void_data_ptr, buf, 111 get_frame_pc (frame)); 112 return val; 113 } 114 } 115 116 static struct value * 117 value_of_builtin_frame_sp_reg (struct frame_info *frame) 118 { 119 #ifdef SP_REGNUM 120 if (SP_REGNUM >= 0) 121 return value_of_register (SP_REGNUM, frame); 122 #endif 123 error ("Standard register ``$sp'' is not available for this target"); 124 } 125 126 static struct value * 127 value_of_builtin_frame_ps_reg (struct frame_info *frame) 128 { 129 #ifdef PS_REGNUM 130 if (PS_REGNUM >= 0) 131 return value_of_register (PS_REGNUM, frame); 132 #endif 133 error ("Standard register ``$ps'' is not available for this target"); 134 } 135 136 extern initialize_file_ftype _initialize_frame_reg; /* -Wmissing-prototypes */ 137 138 void 139 _initialize_frame_reg (void) 140 { 141 /* FIXME: cagney/2002-02-08: At present the local builtin types 142 can't be initialized using _initialize*() or gdbarch. Due mainly 143 to non-multi-arch targets, GDB initializes things piece meal and, 144 as a consequence can leave these types NULL. */ 145 DEPRECATED_REGISTER_GDBARCH_SWAP (builtin_type_frame_reg); 146 147 /* Frame based $fp, $pc, $sp and $ps. These only come into play 148 when the target does not define its own version of these 149 registers. */ 150 user_reg_add_builtin ("fp", value_of_builtin_frame_fp_reg); 151 user_reg_add_builtin ("pc", value_of_builtin_frame_pc_reg); 152 user_reg_add_builtin ("sp", value_of_builtin_frame_sp_reg); 153 user_reg_add_builtin ("ps", value_of_builtin_frame_ps_reg); 154 155 /* NOTE: cagney/2002-04-05: For moment leave the $frame / $gdbframe 156 / $gdb.frame disabled. It isn't yet clear which of the many 157 options is the best. */ 158 if (0) 159 user_reg_add_builtin ("frame", value_of_builtin_frame_reg); 160 } 161