1 /* Traditional frame unwind support, for GDB the GNU Debugger.
3 Copyright 2003 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., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
24 #include "trad-frame.h"
27 /* A traditional frame is unwound by analysing the function prologue
28 and using the information gathered to track registers. For
29 non-optimized frames, the technique is reliable (just need to check
30 for all potential instruction sequences). */
32 struct trad_frame_saved_reg
*
33 trad_frame_alloc_saved_regs (struct frame_info
*next_frame
)
36 struct gdbarch
*gdbarch
= get_frame_arch (next_frame
);
37 int numregs
= NUM_REGS
+ NUM_PSEUDO_REGS
;
38 struct trad_frame_saved_reg
*this_saved_regs
39 = FRAME_OBSTACK_CALLOC (numregs
, struct trad_frame_saved_reg
);
40 for (regnum
= 0; regnum
< numregs
; regnum
++)
42 this_saved_regs
[regnum
].realreg
= regnum
;
43 this_saved_regs
[regnum
].addr
= -1;
45 return this_saved_regs
;
48 enum { REG_VALUE
= -1, REG_UNKNOWN
= -2 };
51 trad_frame_value_p (struct trad_frame_saved_reg this_saved_regs
[], int regnum
)
53 return (this_saved_regs
[regnum
].realreg
== REG_VALUE
);
57 trad_frame_addr_p (struct trad_frame_saved_reg this_saved_regs
[], int regnum
)
59 return (this_saved_regs
[regnum
].realreg
>= 0
60 && this_saved_regs
[regnum
].addr
!= -1);
64 trad_frame_realreg_p (struct trad_frame_saved_reg this_saved_regs
[],
67 return (this_saved_regs
[regnum
].realreg
>= 0
68 && this_saved_regs
[regnum
].addr
== -1);
72 trad_frame_set_value (struct trad_frame_saved_reg this_saved_regs
[],
73 int regnum
, LONGEST val
)
75 /* Make the REALREG invalid, indicating that the ADDR contains the
77 this_saved_regs
[regnum
].realreg
= REG_VALUE
;
78 this_saved_regs
[regnum
].addr
= val
;
82 trad_frame_set_unknown (struct trad_frame_saved_reg this_saved_regs
[],
85 /* Make the REALREG invalid, indicating that the value is not known. */
86 this_saved_regs
[regnum
].realreg
= REG_UNKNOWN
;
87 this_saved_regs
[regnum
].addr
= -1;
91 trad_frame_prev_register (struct frame_info
*next_frame
,
92 struct trad_frame_saved_reg this_saved_regs
[],
93 int regnum
, int *optimizedp
,
94 enum lval_type
*lvalp
, CORE_ADDR
*addrp
,
95 int *realregp
, void *bufferp
)
97 struct gdbarch
*gdbarch
= get_frame_arch (next_frame
);
98 if (trad_frame_addr_p (this_saved_regs
, regnum
))
100 /* The register was saved in memory. */
102 *lvalp
= lval_memory
;
103 *addrp
= this_saved_regs
[regnum
].addr
;
107 /* Read the value in from memory. */
108 get_frame_memory (next_frame
, this_saved_regs
[regnum
].addr
, bufferp
,
109 register_size (gdbarch
, regnum
));
112 else if (trad_frame_realreg_p (this_saved_regs
, regnum
))
114 /* Ask the next frame to return the value of the register. */
115 frame_register_unwind (next_frame
, this_saved_regs
[regnum
].realreg
,
116 optimizedp
, lvalp
, addrp
, realregp
, bufferp
);
118 else if (trad_frame_value_p (this_saved_regs
, regnum
))
120 /* The register's value is available. */
126 store_unsigned_integer (bufferp
, register_size (gdbarch
, regnum
),
127 this_saved_regs
[regnum
].addr
);
131 error ("Register %s not available",
132 gdbarch_register_name (gdbarch
, regnum
));