merge from gcc
[gdb/gnu.git] / gdb / trad-frame.c
blobb0129da906d2c596bea5c143d4629ed5c073c902
1 /* Traditional frame unwind support, for GDB the GNU Debugger.
3 Copyright (C) 2003-2013 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 3 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, see <http://www.gnu.org/licenses/>. */
20 #include "defs.h"
21 #include "frame.h"
22 #include "trad-frame.h"
23 #include "regcache.h"
24 #include "frame-unwind.h"
25 #include "value.h"
27 struct trad_frame_cache
29 struct frame_info *this_frame;
30 CORE_ADDR this_base;
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 *this_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 (this_frame);
42 this_trad_cache->this_frame = this_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 *this_frame)
54 int regnum;
55 struct gdbarch *gdbarch = get_frame_arch (this_frame);
56 int numregs = gdbarch_num_regs (gdbarch) + gdbarch_num_pseudo_regs (gdbarch);
57 struct trad_frame_saved_reg *this_saved_regs
58 = 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 { TF_REG_VALUE = -1, TF_REG_UNKNOWN = -2 };
70 int
71 trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs[], int regnum)
73 return (this_saved_regs[regnum].realreg == TF_REG_VALUE);
76 int
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);
83 int
84 trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs[],
85 int regnum)
87 return (this_saved_regs[regnum].realreg >= 0
88 && this_saved_regs[regnum].addr == -1);
91 void
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
96 register's value. */
97 this_saved_regs[regnum].realreg = TF_REG_VALUE;
98 this_saved_regs[regnum].addr = val;
101 void
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);
110 void
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;
118 void
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;
125 void
126 trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs[],
127 int regnum)
129 /* Make the REALREG invalid, indicating that the value is not known. */
130 this_saved_regs[regnum].realreg = TF_REG_UNKNOWN;
131 this_saved_regs[regnum].addr = -1;
134 struct value *
135 trad_frame_get_prev_register (struct frame_info *this_frame,
136 struct trad_frame_saved_reg this_saved_regs[],
137 int regnum)
139 if (trad_frame_addr_p (this_saved_regs, regnum))
140 /* The register was saved in memory. */
141 return frame_unwind_got_memory (this_frame, regnum,
142 this_saved_regs[regnum].addr);
143 else if (trad_frame_realreg_p (this_saved_regs, regnum))
144 return frame_unwind_got_register (this_frame, regnum,
145 this_saved_regs[regnum].realreg);
146 else if (trad_frame_value_p (this_saved_regs, regnum))
147 /* The register's value is available. */
148 return frame_unwind_got_constant (this_frame, regnum,
149 this_saved_regs[regnum].addr);
150 else
151 return frame_unwind_got_optimized (this_frame, regnum);
154 struct value *
155 trad_frame_get_register (struct trad_frame_cache *this_trad_cache,
156 struct frame_info *this_frame,
157 int regnum)
159 return trad_frame_get_prev_register (this_frame, this_trad_cache->prev_regs,
160 regnum);
163 void
164 trad_frame_set_id (struct trad_frame_cache *this_trad_cache,
165 struct frame_id this_id)
167 this_trad_cache->this_id = this_id;
170 void
171 trad_frame_get_id (struct trad_frame_cache *this_trad_cache,
172 struct frame_id *this_id)
174 (*this_id) = this_trad_cache->this_id;
177 void
178 trad_frame_set_this_base (struct trad_frame_cache *this_trad_cache,
179 CORE_ADDR this_base)
181 this_trad_cache->this_base = this_base;
184 CORE_ADDR
185 trad_frame_get_this_base (struct trad_frame_cache *this_trad_cache)
187 return this_trad_cache->this_base;