1 /* Traditional frame unwind support, for GDB the GNU Debugger.
3 Copyright (C) 2003, 2004, 2007 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/>. */
22 #include "trad-frame.h"
25 struct trad_frame_cache
27 struct frame_info
*next_frame
;
29 struct trad_frame_saved_reg
*prev_regs
;
30 struct frame_id this_id
;
33 struct trad_frame_cache
*
34 trad_frame_cache_zalloc (struct frame_info
*next_frame
)
36 struct trad_frame_cache
*this_trad_cache
;
38 this_trad_cache
= FRAME_OBSTACK_ZALLOC (struct trad_frame_cache
);
39 this_trad_cache
->prev_regs
= trad_frame_alloc_saved_regs (next_frame
);
40 this_trad_cache
->next_frame
= next_frame
;
41 return this_trad_cache
;
44 /* A traditional frame is unwound by analysing the function prologue
45 and using the information gathered to track registers. For
46 non-optimized frames, the technique is reliable (just need to check
47 for all potential instruction sequences). */
49 struct trad_frame_saved_reg
*
50 trad_frame_alloc_saved_regs (struct frame_info
*next_frame
)
53 struct gdbarch
*gdbarch
= get_frame_arch (next_frame
);
54 int numregs
= gdbarch_num_regs (current_gdbarch
)
55 + gdbarch_num_pseudo_regs (current_gdbarch
);
56 struct trad_frame_saved_reg
*this_saved_regs
57 = FRAME_OBSTACK_CALLOC (numregs
, struct trad_frame_saved_reg
);
58 for (regnum
= 0; regnum
< numregs
; regnum
++)
60 this_saved_regs
[regnum
].realreg
= regnum
;
61 this_saved_regs
[regnum
].addr
= -1;
63 return this_saved_regs
;
66 enum { REG_VALUE
= -1, REG_UNKNOWN
= -2 };
69 trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs
[], int regnum
)
71 return (this_saved_regs
[regnum
].realreg
== REG_VALUE
);
75 trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs
[], int regnum
)
77 return (this_saved_regs
[regnum
].realreg
>= 0
78 && this_saved_regs
[regnum
].addr
!= -1);
82 trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs
[],
85 return (this_saved_regs
[regnum
].realreg
>= 0
86 && this_saved_regs
[regnum
].addr
== -1);
90 trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs
[],
91 int regnum
, LONGEST val
)
93 /* Make the REALREG invalid, indicating that the ADDR contains the
95 this_saved_regs
[regnum
].realreg
= REG_VALUE
;
96 this_saved_regs
[regnum
].addr
= val
;
100 trad_frame_set_reg_value (struct trad_frame_cache
*this_trad_cache
,
101 int regnum
, LONGEST val
)
103 /* External interface for users of trad_frame_cache
104 (who cannot access the prev_regs object directly). */
105 trad_frame_set_value (this_trad_cache
->prev_regs
, regnum
, val
);
109 trad_frame_set_reg_realreg (struct trad_frame_cache
*this_trad_cache
,
110 int regnum
, int realreg
)
112 this_trad_cache
->prev_regs
[regnum
].realreg
= realreg
;
113 this_trad_cache
->prev_regs
[regnum
].addr
= -1;
117 trad_frame_set_reg_addr (struct trad_frame_cache
*this_trad_cache
,
118 int regnum
, CORE_ADDR addr
)
120 this_trad_cache
->prev_regs
[regnum
].addr
= addr
;
124 trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs
[],
127 /* Make the REALREG invalid, indicating that the value is not known. */
128 this_saved_regs
[regnum
].realreg
= REG_UNKNOWN
;
129 this_saved_regs
[regnum
].addr
= -1;
133 trad_frame_get_prev_register (struct frame_info
*next_frame
,
134 struct trad_frame_saved_reg this_saved_regs
[],
135 int regnum
, int *optimizedp
,
136 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
137 int *realregp
, gdb_byte
*bufferp
)
139 struct gdbarch
*gdbarch
= get_frame_arch (next_frame
);
140 if (trad_frame_addr_p (this_saved_regs
, regnum
))
142 /* The register was saved in memory. */
144 *lvalp
= lval_memory
;
145 *addrp
= this_saved_regs
[regnum
].addr
;
149 /* Read the value in from memory. */
150 get_frame_memory (next_frame
, this_saved_regs
[regnum
].addr
, bufferp
,
151 register_size (gdbarch
, regnum
));
154 else if (trad_frame_realreg_p (this_saved_regs
, regnum
))
157 *lvalp
= lval_register
;
159 *realregp
= this_saved_regs
[regnum
].realreg
;
160 /* Ask the next frame to return the value of the register. */
162 frame_unwind_register (next_frame
, (*realregp
), bufferp
);
164 else if (trad_frame_value_p (this_saved_regs
, regnum
))
166 /* The register's value is available. */
172 store_unsigned_integer (bufferp
, register_size (gdbarch
, regnum
),
173 this_saved_regs
[regnum
].addr
);
177 error (_("Register %s not available"),
178 gdbarch_register_name (gdbarch
, regnum
));
183 trad_frame_get_register (struct trad_frame_cache
*this_trad_cache
,
184 struct frame_info
*next_frame
,
185 int regnum
, int *optimizedp
,
186 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
187 int *realregp
, gdb_byte
*bufferp
)
189 trad_frame_get_prev_register (next_frame
, this_trad_cache
->prev_regs
,
190 regnum
, optimizedp
, lvalp
, addrp
, realregp
,
195 trad_frame_set_id (struct trad_frame_cache
*this_trad_cache
,
196 struct frame_id this_id
)
198 this_trad_cache
->this_id
= this_id
;
202 trad_frame_get_id (struct trad_frame_cache
*this_trad_cache
,
203 struct frame_id
*this_id
)
205 (*this_id
) = this_trad_cache
->this_id
;
209 trad_frame_set_this_base (struct trad_frame_cache
*this_trad_cache
,
212 this_trad_cache
->this_base
= this_base
;
216 trad_frame_get_this_base (struct trad_frame_cache
*this_trad_cache
)
218 return this_trad_cache
->this_base
;