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
;