1 /* Traditional frame unwind support, for GDB the GNU Debugger.
3 Copyright (C) 2003, 2004, 2007, 2008, 2009, 2010
4 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
23 #include "trad-frame.h"
25 #include "frame-unwind.h"
28 struct trad_frame_cache
30 struct frame_info *this_frame;
32 struct trad_frame_saved_reg *prev_regs;
33 struct frame_id this_id;
36 struct trad_frame_cache *
37 trad_frame_cache_zalloc (struct frame_info *this_frame)
39 struct trad_frame_cache *this_trad_cache;
41 this_trad_cache = FRAME_OBSTACK_ZALLOC (struct trad_frame_cache);
42 this_trad_cache->prev_regs = trad_frame_alloc_saved_regs (this_frame);
43 this_trad_cache->this_frame = this_frame;
44 return this_trad_cache;
47 /* A traditional frame is unwound by analysing the function prologue
48 and using the information gathered to track registers. For
49 non-optimized frames, the technique is reliable (just need to check
50 for all potential instruction sequences). */
52 struct trad_frame_saved_reg *
53 trad_frame_alloc_saved_regs (struct frame_info *this_frame)
56 struct gdbarch *gdbarch = get_frame_arch (this_frame);
57 int numregs = gdbarch_num_regs (gdbarch) + gdbarch_num_pseudo_regs (gdbarch);
58 struct trad_frame_saved_reg *this_saved_regs
59 = FRAME_OBSTACK_CALLOC (numregs, struct trad_frame_saved_reg);
60 for (regnum = 0; regnum < numregs; regnum++)
62 this_saved_regs[regnum].realreg = regnum;
63 this_saved_regs[regnum].addr = -1;
65 return this_saved_regs;
68 enum { REG_VALUE = -1, REG_UNKNOWN = -2 };
71 trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs[], int regnum)
73 return (this_saved_regs[regnum].realreg == REG_VALUE);
77 trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs[], int regnum)
79 return (this_saved_regs[regnum].realreg >= 0
80 && this_saved_regs[regnum].addr != -1);
84 trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs[],
87 return (this_saved_regs[regnum].realreg >= 0
88 && this_saved_regs[regnum].addr == -1);
92 trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs[],
93 int regnum, LONGEST val)
95 /* Make the REALREG invalid, indicating that the ADDR contains the
97 this_saved_regs[regnum].realreg = REG_VALUE;
98 this_saved_regs[regnum].addr = val;
102 trad_frame_set_reg_value (struct trad_frame_cache *this_trad_cache,
103 int regnum, LONGEST val)
105 /* External interface for users of trad_frame_cache
106 (who cannot access the prev_regs object directly). */
107 trad_frame_set_value (this_trad_cache->prev_regs, regnum, val);
111 trad_frame_set_reg_realreg (struct trad_frame_cache *this_trad_cache,
112 int regnum, int realreg)
114 this_trad_cache->prev_regs[regnum].realreg = realreg;
115 this_trad_cache->prev_regs[regnum].addr = -1;
119 trad_frame_set_reg_addr (struct trad_frame_cache *this_trad_cache,
120 int regnum, CORE_ADDR addr)
122 this_trad_cache->prev_regs[regnum].addr = addr;
126 trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs[],
129 /* Make the REALREG invalid, indicating that the value is not known. */
130 this_saved_regs[regnum].realreg = REG_UNKNOWN;
131 this_saved_regs[regnum].addr = -1;
135 trad_frame_get_prev_register (struct frame_info *this_frame,
136 struct trad_frame_saved_reg this_saved_regs[],
139 struct gdbarch *gdbarch = get_frame_arch (this_frame);
140 if (trad_frame_addr_p (this_saved_regs, regnum))
141 /* The register was saved in memory. */
142 return frame_unwind_got_memory (this_frame, regnum,
143 this_saved_regs[regnum].addr);
144 else if (trad_frame_realreg_p (this_saved_regs, regnum))
145 return frame_unwind_got_register (this_frame, regnum,
146 this_saved_regs[regnum].realreg);
147 else if (trad_frame_value_p (this_saved_regs, regnum))
148 /* The register's value is available. */
149 return frame_unwind_got_constant (this_frame, regnum,
150 this_saved_regs[regnum].addr);
152 return frame_unwind_got_optimized (this_frame, regnum);
156 trad_frame_get_register (struct trad_frame_cache *this_trad_cache,
157 struct frame_info *this_frame,
160 return trad_frame_get_prev_register (this_frame, this_trad_cache->prev_regs,
165 trad_frame_set_id (struct trad_frame_cache *this_trad_cache,
166 struct frame_id this_id)
168 this_trad_cache->this_id = this_id;
172 trad_frame_get_id (struct trad_frame_cache *this_trad_cache,
173 struct frame_id *this_id)
175 (*this_id) = this_trad_cache->this_id;
179 trad_frame_set_this_base (struct trad_frame_cache *this_trad_cache,
182 this_trad_cache->this_base = this_base;
186 trad_frame_get_this_base (struct trad_frame_cache *this_trad_cache)
188 return this_trad_cache->this_base;