1 /* Traditional frame unwind support, for GDB the GNU Debugger.
3 Copyright 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GDB.
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.
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.
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. */
24 #include "trad-frame.h"
27 struct trad_frame_cache
29 struct frame_info *next_frame;
31 struct trad_frame_saved_reg *prev_regs;
32 struct frame_id this_id;
35 struct trad_frame_cache *
36 trad_frame_cache_zalloc (struct frame_info *next_frame)
38 struct trad_frame_cache *this_trad_cache;
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;
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). */
51 struct trad_frame_saved_reg *
52 trad_frame_alloc_saved_regs (struct frame_info *next_frame)
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++)
61 this_saved_regs[regnum].realreg = regnum;
62 this_saved_regs[regnum].addr = -1;
64 return this_saved_regs;
67 enum { REG_VALUE = -1, REG_UNKNOWN = -2 };
70 trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs[], int regnum)
72 return (this_saved_regs[regnum].realreg == REG_VALUE);
76 trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs[], int regnum)
78 return (this_saved_regs[regnum].realreg >= 0
79 && this_saved_regs[regnum].addr != -1);
83 trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs[],
86 return (this_saved_regs[regnum].realreg >= 0
87 && this_saved_regs[regnum].addr == -1);
91 trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs[],
92 int regnum, LONGEST val)
94 /* Make the REALREG invalid, indicating that the ADDR contains the
96 this_saved_regs[regnum].realreg = REG_VALUE;
97 this_saved_regs[regnum].addr = val;
101 trad_frame_set_reg_addr (struct trad_frame_cache *this_trad_cache,
102 int regnum, CORE_ADDR addr)
104 this_trad_cache->prev_regs[regnum].addr = addr;
108 trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs[],
111 /* Make the REALREG invalid, indicating that the value is not known. */
112 this_saved_regs[regnum].realreg = REG_UNKNOWN;
113 this_saved_regs[regnum].addr = -1;
117 trad_frame_prev_register (struct frame_info *next_frame,
118 struct trad_frame_saved_reg this_saved_regs[],
119 int regnum, int *optimizedp,
120 enum lval_type *lvalp, CORE_ADDR *addrp,
121 int *realregp, void *bufferp)
123 struct gdbarch *gdbarch = get_frame_arch (next_frame);
124 if (trad_frame_addr_p (this_saved_regs, regnum))
126 /* The register was saved in memory. */
128 *lvalp = lval_memory;
129 *addrp = this_saved_regs[regnum].addr;
133 /* Read the value in from memory. */
134 get_frame_memory (next_frame, this_saved_regs[regnum].addr, bufferp,
135 register_size (gdbarch, regnum));
138 else if (trad_frame_realreg_p (this_saved_regs, regnum))
140 /* Ask the next frame to return the value of the register. */
141 frame_register_unwind (next_frame, this_saved_regs[regnum].realreg,
142 optimizedp, lvalp, addrp, realregp, bufferp);
144 else if (trad_frame_value_p (this_saved_regs, regnum))
146 /* The register's value is available. */
152 store_unsigned_integer (bufferp, register_size (gdbarch, regnum),
153 this_saved_regs[regnum].addr);
157 error ("Register %s not available",
158 gdbarch_register_name (gdbarch, regnum));
163 trad_frame_get_register (struct trad_frame_cache *this_trad_cache,
164 struct frame_info *next_frame,
165 int regnum, int *optimizedp,
166 enum lval_type *lvalp, CORE_ADDR *addrp,
167 int *realregp, void *bufferp)
169 trad_frame_prev_register (next_frame, this_trad_cache->prev_regs,
170 regnum, optimizedp, lvalp, addrp, realregp,
175 trad_frame_set_id (struct trad_frame_cache *this_trad_cache,
176 struct frame_id this_id)
178 this_trad_cache->this_id = this_id;
182 trad_frame_get_id (struct trad_frame_cache *this_trad_cache,
183 struct frame_id *this_id)
185 (*this_id) = this_trad_cache->this_id;