1 /* Builtin frame register, for GDB, the GNU debugger. 2 3 Copyright (C) 2002-2019 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 3 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, see <http://www.gnu.org/licenses/>. */ 21 22 #include "defs.h" 23 #include "user-regs.h" 24 #include "frame.h" 25 #include "gdbtypes.h" 26 #include "value.h" 27 static struct value * 28 value_of_builtin_frame_fp_reg (struct frame_info *frame, const void *baton) 29 { 30 struct gdbarch *gdbarch = get_frame_arch (frame); 31 32 if (gdbarch_deprecated_fp_regnum (gdbarch) >= 0) 33 /* NOTE: cagney/2003-04-24: Since the mere presence of "fp" in the 34 register name table overrides this built-in $fp register, there 35 is no real reason for this gdbarch_deprecated_fp_regnum trickery here. 36 An architecture wanting to implement "$fp" as alias for a raw 37 register can do so by adding "fp" to register name table (mind 38 you, doing this is probably a dangerous thing). */ 39 return value_of_register (gdbarch_deprecated_fp_regnum (gdbarch), 40 frame); 41 else 42 { 43 struct type *data_ptr_type = builtin_type (gdbarch)->builtin_data_ptr; 44 struct value *val = allocate_value (data_ptr_type); 45 gdb_byte *buf = value_contents_raw (val); 46 47 gdbarch_address_to_pointer (gdbarch, data_ptr_type, 48 buf, get_frame_base_address (frame)); 49 return val; 50 } 51 } 52 53 static struct value * 54 value_of_builtin_frame_pc_reg (struct frame_info *frame, const void *baton) 55 { 56 struct gdbarch *gdbarch = get_frame_arch (frame); 57 58 if (gdbarch_pc_regnum (gdbarch) >= 0) 59 return value_of_register (gdbarch_pc_regnum (gdbarch), frame); 60 else 61 { 62 struct type *func_ptr_type = builtin_type (gdbarch)->builtin_func_ptr; 63 struct value *val = allocate_value (func_ptr_type); 64 gdb_byte *buf = value_contents_raw (val); 65 66 gdbarch_address_to_pointer (gdbarch, func_ptr_type, 67 buf, get_frame_pc (frame)); 68 return val; 69 } 70 } 71 72 static struct value * 73 value_of_builtin_frame_sp_reg (struct frame_info *frame, const void *baton) 74 { 75 struct gdbarch *gdbarch = get_frame_arch (frame); 76 77 if (gdbarch_sp_regnum (gdbarch) >= 0) 78 return value_of_register (gdbarch_sp_regnum (gdbarch), frame); 79 error (_("Standard register ``$sp'' is not available for this target")); 80 } 81 82 static struct value * 83 value_of_builtin_frame_ps_reg (struct frame_info *frame, const void *baton) 84 { 85 struct gdbarch *gdbarch = get_frame_arch (frame); 86 87 if (gdbarch_ps_regnum (gdbarch) >= 0) 88 return value_of_register (gdbarch_ps_regnum (gdbarch), frame); 89 error (_("Standard register ``$ps'' is not available for this target")); 90 } 91 92 void 93 _initialize_frame_reg (void) 94 { 95 /* Frame based $fp, $pc, $sp and $ps. These only come into play 96 when the target does not define its own version of these 97 registers. */ 98 user_reg_add_builtin ("fp", value_of_builtin_frame_fp_reg, NULL); 99 user_reg_add_builtin ("pc", value_of_builtin_frame_pc_reg, NULL); 100 user_reg_add_builtin ("sp", value_of_builtin_frame_sp_reg, NULL); 101 user_reg_add_builtin ("ps", value_of_builtin_frame_ps_reg, NULL); 102 } 103