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/tmp/gdb-7.10/gdb/dwarf2-frame.h
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1 /* Frame unwinder for frames with DWARF Call Frame Information.
2 
3  Copyright (C) 2003-2015 Free Software Foundation, Inc.
4 
5  Contributed by Mark Kettenis.
6 
7  This file is part of GDB.
8 
9  This program is free software; you can redistribute it and/or modify
10  it under the terms of the GNU General Public License as published by
11  the Free Software Foundation; either version 3 of the License, or
12  (at your option) any later version.
13 
14  This program is distributed in the hope that it will be useful,
15  but WITHOUT ANY WARRANTY; without even the implied warranty of
16  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17  GNU General Public License for more details.
18 
19  You should have received a copy of the GNU General Public License
20  along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 
22 #ifndef DWARF2_FRAME_H
23 #define DWARF2_FRAME_H 1
24 
25 struct gdbarch;
26 struct objfile;
27 struct frame_info;
28 struct dwarf2_per_cu_data;
29 struct agent_expr;
30 struct axs_value;
31 
32 /* Register rule. */
33 
35 {
36  /* Make certain that 0 maps onto the correct enum value; the
37  corresponding structure is being initialized using memset zero.
38  This indicates that CFI didn't provide any information at all
39  about a register, leaving how to obtain its value totally
40  unspecified. */
42 
43  /* The term "undefined" comes from the DWARF2 CFI spec which this
44  code is moddeling; it indicates that the register's value is
45  "undefined". GCC uses the less formal term "unsaved". Its
46  definition is a combination of REG_UNDEFINED and REG_UNSPECIFIED.
47  The failure to differentiate the two helps explain a few problems
48  with the CFI generated by GCC. */
54 
55  /* These are defined in Dwarf3. */
58 
59  /* These aren't defined by the DWARF2 CFI specification, but are
60  used internally by GDB. */
61  DWARF2_FRAME_REG_FN, /* Call a registered function. */
62  DWARF2_FRAME_REG_RA, /* Return Address. */
63  DWARF2_FRAME_REG_RA_OFFSET, /* Return Address with offset. */
64  DWARF2_FRAME_REG_CFA, /* Call Frame Address. */
65  DWARF2_FRAME_REG_CFA_OFFSET /* Call Frame Address with offset. */
66 };
67 
68 /* Register state. */
69 
71 {
72  /* Each register save state can be described in terms of a CFA slot,
73  another register, or a location expression. */
74  union {
77  const gdb_byte *exp;
78  struct value *(*fn) (struct frame_info *this_frame, void **this_cache,
79  int regnum);
80  } loc;
83 };
84 
85 /* Set the architecture-specific register state initialization
86  function for GDBARCH to INIT_REG. */
87 
88 extern void dwarf2_frame_set_init_reg (struct gdbarch *gdbarch,
89  void (*init_reg) (struct gdbarch *, int,
90  struct dwarf2_frame_state_reg *,
91  struct frame_info *));
92 
93 /* Set the architecture-specific signal trampoline recognition
94  function for GDBARCH to SIGNAL_FRAME_P. */
95 
96 extern void
97  dwarf2_frame_set_signal_frame_p (struct gdbarch *gdbarch,
98  int (*signal_frame_p) (struct gdbarch *,
99  struct frame_info *));
100 
101 /* Set the architecture-specific adjustment of .eh_frame and .debug_frame
102  register numbers. */
103 
104 extern void
105  dwarf2_frame_set_adjust_regnum (struct gdbarch *gdbarch,
106  int (*adjust_regnum) (struct gdbarch *,
107  int, int));
108 
109 /* Append the DWARF-2 frame unwinders to GDBARCH's list. */
110 
111 void dwarf2_append_unwinders (struct gdbarch *gdbarch);
112 
113 /* Return the frame base methods for the function that contains PC, or
114  NULL if it can't be handled by the DWARF CFI frame unwinder. */
115 
116 extern const struct frame_base *
117  dwarf2_frame_base_sniffer (struct frame_info *this_frame);
118 
119 /* Compute the DWARF CFA for a frame. */
120 
121 CORE_ADDR dwarf2_frame_cfa (struct frame_info *this_frame);
122 
123 /* Find the CFA information for PC.
124 
125  Return 1 if a register is used for the CFA, or 0 if another
126  expression is used. Throw an exception on error.
127 
128  GDBARCH is the architecture to use.
129  DATA is the per-CU data.
130 
131  REGNUM_OUT is an out parameter that is set to the register number.
132  OFFSET_OUT is the offset to use from this register.
133  These are only filled in when 1 is returned.
134 
135  TEXT_OFFSET_OUT, CFA_START_OUT, and CFA_END_OUT describe the CFA
136  in other cases. These are only used when 0 is returned. */
137 
138 extern int dwarf2_fetch_cfa_info (struct gdbarch *gdbarch, CORE_ADDR pc,
139  struct dwarf2_per_cu_data *data,
140  int *regnum_out, LONGEST *offset_out,
141  CORE_ADDR *text_offset_out,
142  const gdb_byte **cfa_start_out,
143  const gdb_byte **cfa_end_out);
144 
145 #endif /* dwarf2-frame.h */
bfd_vma CORE_ADDR
Definition: common-types.h:41
void dwarf2_frame_set_signal_frame_p(struct gdbarch *gdbarch, int(*signal_frame_p)(struct gdbarch *, struct frame_info *))
Definition: dwarf2-frame.c:806
dwarf2_frame_reg_rule
Definition: dwarf2-frame.h:34
union dwarf2_frame_state_reg::@51 loc
Definition: ax.h:95
void dwarf2_frame_set_adjust_regnum(struct gdbarch *gdbarch, int(*adjust_regnum)(struct gdbarch *, int, int))
CORE_ADDR dwarf2_frame_cfa(struct frame_info *this_frame)
int dwarf2_fetch_cfa_info(struct gdbarch *gdbarch, CORE_ADDR pc, struct dwarf2_per_cu_data *data, int *regnum_out, LONGEST *offset_out, CORE_ADDR *text_offset_out, const gdb_byte **cfa_start_out, const gdb_byte **cfa_end_out)
Definition: dwarf2-frame.c:893
const gdb_byte * exp
Definition: dwarf2-frame.h:77
void dwarf2_append_unwinders(struct gdbarch *gdbarch)
int regnum
Definition: aarch64-tdep.c:69
const struct frame_base * dwarf2_frame_base_sniffer(struct frame_info *this_frame)
Definition: value.c:172
void dwarf2_frame_set_init_reg(struct gdbarch *gdbarch, void(*init_reg)(struct gdbarch *, int, struct dwarf2_frame_state_reg *, struct frame_info *))
Definition: dwarf2-frame.c:780
bfd_byte gdb_byte
Definition: common-types.h:38
unsigned long long ULONGEST
Definition: common-types.h:53
enum dwarf2_frame_reg_rule how
Definition: dwarf2-frame.h:82
long long LONGEST
Definition: common-types.h:52