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 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., 51 Franklin Street, Fifth Floor,
20 Boston, MA 02110-1301, 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
= gdbarch_num_regs (current_gdbarch
)
57 + gdbarch_num_pseudo_regs (current_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
*next_frame
,
136 struct trad_frame_saved_reg this_saved_regs
[],
137 int regnum
, int *optimizedp
,
138 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
139 int *realregp
, gdb_byte
*bufferp
)
141 struct gdbarch
*gdbarch
= get_frame_arch (next_frame
);
142 if (trad_frame_addr_p (this_saved_regs
, regnum
))
144 /* The register was saved in memory. */
146 *lvalp
= lval_memory
;
147 *addrp
= this_saved_regs
[regnum
].addr
;
151 /* Read the value in from memory. */
152 get_frame_memory (next_frame
, this_saved_regs
[regnum
].addr
, bufferp
,
153 register_size (gdbarch
, regnum
));
156 else if (trad_frame_realreg_p (this_saved_regs
, regnum
))
159 *lvalp
= lval_register
;
161 *realregp
= this_saved_regs
[regnum
].realreg
;
162 /* Ask the next frame to return the value of the register. */
164 frame_unwind_register (next_frame
, (*realregp
), bufferp
);
166 else if (trad_frame_value_p (this_saved_regs
, regnum
))
168 /* The register's value is available. */
174 store_unsigned_integer (bufferp
, register_size (gdbarch
, regnum
),
175 this_saved_regs
[regnum
].addr
);
179 error (_("Register %s not available"),
180 gdbarch_register_name (gdbarch
, regnum
));
185 trad_frame_get_register (struct trad_frame_cache
*this_trad_cache
,
186 struct frame_info
*next_frame
,
187 int regnum
, int *optimizedp
,
188 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
189 int *realregp
, gdb_byte
*bufferp
)
191 trad_frame_get_prev_register (next_frame
, this_trad_cache
->prev_regs
,
192 regnum
, optimizedp
, lvalp
, addrp
, realregp
,
197 trad_frame_set_id (struct trad_frame_cache
*this_trad_cache
,
198 struct frame_id this_id
)
200 this_trad_cache
->this_id
= this_id
;
204 trad_frame_get_id (struct trad_frame_cache
*this_trad_cache
,
205 struct frame_id
*this_id
)
207 (*this_id
) = this_trad_cache
->this_id
;
211 trad_frame_set_this_base (struct trad_frame_cache
*this_trad_cache
,
214 this_trad_cache
->this_base
= this_base
;
218 trad_frame_get_this_base (struct trad_frame_cache
*this_trad_cache
)
220 return this_trad_cache
->this_base
;