1/* Traditional frame unwind support, for GDB the GNU Debugger. 2 3 Copyright 2003, 2004 Free Software Foundation, Inc. 4 5 This file is part of GDB. 6 7 This program is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 2 of the License, or 10 (at your option) any later version. 11 12 This program is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with this program; if not, write to the Free Software 19 Foundation, Inc., 59 Temple Place - Suite 330, 20 Boston, MA 02111-1307, USA. */ 21 22#include "defs.h" 23#include "frame.h" 24#include "trad-frame.h" 25#include "regcache.h" 26 27struct trad_frame_cache 28{ 29 struct frame_info *next_frame; 30 CORE_ADDR this_base; 31 struct trad_frame_saved_reg *prev_regs; 32 struct frame_id this_id; 33}; 34 35struct trad_frame_cache * 36trad_frame_cache_zalloc (struct frame_info *next_frame) 37{ 38 struct trad_frame_cache *this_trad_cache; 39 40 this_trad_cache = FRAME_OBSTACK_ZALLOC (struct trad_frame_cache); 41 this_trad_cache->prev_regs = trad_frame_alloc_saved_regs (next_frame); 42 this_trad_cache->next_frame = next_frame; 43 return this_trad_cache; 44} 45 46/* A traditional frame is unwound by analysing the function prologue 47 and using the information gathered to track registers. For 48 non-optimized frames, the technique is reliable (just need to check 49 for all potential instruction sequences). */ 50 51struct trad_frame_saved_reg * 52trad_frame_alloc_saved_regs (struct frame_info *next_frame) 53{ 54 int regnum; 55 struct gdbarch *gdbarch = get_frame_arch (next_frame); 56 int numregs = NUM_REGS + NUM_PSEUDO_REGS; 57 struct trad_frame_saved_reg *this_saved_regs 58 = FRAME_OBSTACK_CALLOC (numregs, struct trad_frame_saved_reg); 59 for (regnum = 0; regnum < numregs; regnum++) 60 { 61 this_saved_regs[regnum].realreg = regnum; 62 this_saved_regs[regnum].addr = -1; 63 } 64 return this_saved_regs; 65} 66 67enum { REG_VALUE = -1, REG_UNKNOWN = -2 }; 68 69int 70trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs[], int regnum) 71{ 72 return (this_saved_regs[regnum].realreg == REG_VALUE); 73} 74 75int 76trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs[], int regnum) 77{ 78 return (this_saved_regs[regnum].realreg >= 0 79 && this_saved_regs[regnum].addr != -1); 80} 81 82int 83trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs[], 84 int regnum) 85{ 86 return (this_saved_regs[regnum].realreg >= 0 87 && this_saved_regs[regnum].addr == -1); 88} 89 90void 91trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs[], 92 int regnum, LONGEST val) 93{ 94 /* Make the REALREG invalid, indicating that the ADDR contains the 95 register's value. */ 96 this_saved_regs[regnum].realreg = REG_VALUE; 97 this_saved_regs[regnum].addr = val; 98} 99 100void 101trad_frame_set_reg_realreg (struct trad_frame_cache *this_trad_cache, 102 int regnum, int realreg) 103{ 104 this_trad_cache->prev_regs[regnum].realreg = realreg; 105 this_trad_cache->prev_regs[regnum].addr = -1; 106} 107 108void 109trad_frame_set_reg_addr (struct trad_frame_cache *this_trad_cache, 110 int regnum, CORE_ADDR addr) 111{ 112 this_trad_cache->prev_regs[regnum].addr = addr; 113} 114 115void 116trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs[], 117 int regnum) 118{ 119 /* Make the REALREG invalid, indicating that the value is not known. */ 120 this_saved_regs[regnum].realreg = REG_UNKNOWN; 121 this_saved_regs[regnum].addr = -1; 122} 123 124void 125trad_frame_get_prev_register (struct frame_info *next_frame, 126 struct trad_frame_saved_reg this_saved_regs[], 127 int regnum, int *optimizedp, 128 enum lval_type *lvalp, CORE_ADDR *addrp, 129 int *realregp, void *bufferp) 130{ 131 struct gdbarch *gdbarch = get_frame_arch (next_frame); 132 if (trad_frame_addr_p (this_saved_regs, regnum)) 133 { 134 /* The register was saved in memory. */ 135 *optimizedp = 0; 136 *lvalp = lval_memory; 137 *addrp = this_saved_regs[regnum].addr; 138 *realregp = -1; 139 if (bufferp != NULL) 140 { 141 /* Read the value in from memory. */ 142 get_frame_memory (next_frame, this_saved_regs[regnum].addr, bufferp, 143 register_size (gdbarch, regnum)); 144 } 145 } 146 else if (trad_frame_realreg_p (this_saved_regs, regnum)) 147 { 148 /* Ask the next frame to return the value of the register. */ 149 frame_register_unwind (next_frame, this_saved_regs[regnum].realreg, 150 optimizedp, lvalp, addrp, realregp, bufferp); 151 } 152 else if (trad_frame_value_p (this_saved_regs, regnum)) 153 { 154 /* The register's value is available. */ 155 *optimizedp = 0; 156 *lvalp = not_lval; 157 *addrp = 0; 158 *realregp = -1; 159 if (bufferp != NULL) 160 store_unsigned_integer (bufferp, register_size (gdbarch, regnum), 161 this_saved_regs[regnum].addr); 162 } 163 else 164 { 165 error ("Register %s not available", 166 gdbarch_register_name (gdbarch, regnum)); 167 } 168} 169 170void 171trad_frame_get_register (struct trad_frame_cache *this_trad_cache, 172 struct frame_info *next_frame, 173 int regnum, int *optimizedp, 174 enum lval_type *lvalp, CORE_ADDR *addrp, 175 int *realregp, void *bufferp) 176{ 177 trad_frame_get_prev_register (next_frame, this_trad_cache->prev_regs, 178 regnum, optimizedp, lvalp, addrp, realregp, 179 bufferp); 180} 181 182void 183trad_frame_set_id (struct trad_frame_cache *this_trad_cache, 184 struct frame_id this_id) 185{ 186 this_trad_cache->this_id = this_id; 187} 188 189void 190trad_frame_get_id (struct trad_frame_cache *this_trad_cache, 191 struct frame_id *this_id) 192{ 193 (*this_id) = this_trad_cache->this_id; 194} 195 196void 197trad_frame_set_this_base (struct trad_frame_cache *this_trad_cache, 198 CORE_ADDR this_base) 199{ 200 this_trad_cache->this_base = this_base; 201} 202 203CORE_ADDR 204trad_frame_get_this_base (struct trad_frame_cache *this_trad_cache) 205{ 206 return this_trad_cache->this_base; 207} 208