1 /* Frame unwinder for frames with DWARF Call Frame Information.
3 Copyright (C) 2003-2017 Free Software Foundation, Inc.
5 Contributed by Mark Kettenis.
7 This file is part of GDB.
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.
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.
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/>. */
22 #ifndef DWARF2_FRAME_H
23 #define DWARF2_FRAME_H 1
28 struct dwarf2_per_cu_data
;
34 enum dwarf2_frame_reg_rule
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
41 DWARF2_FRAME_REG_UNSPECIFIED
= 0,
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. */
49 DWARF2_FRAME_REG_UNDEFINED
,
50 DWARF2_FRAME_REG_SAVED_OFFSET
,
51 DWARF2_FRAME_REG_SAVED_REG
,
52 DWARF2_FRAME_REG_SAVED_EXP
,
53 DWARF2_FRAME_REG_SAME_VALUE
,
55 /* These are defined in Dwarf3. */
56 DWARF2_FRAME_REG_SAVED_VAL_OFFSET
,
57 DWARF2_FRAME_REG_SAVED_VAL_EXP
,
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. */
70 struct dwarf2_frame_state_reg
72 /* Each register save state can be described in terms of a CFA slot,
73 another register, or a location expression. */
78 struct value
*(*fn
) (struct frame_info
*this_frame
, void **this_cache
,
82 enum dwarf2_frame_reg_rule how
;
92 struct dwarf2_frame_state_reg_info
94 struct dwarf2_frame_state_reg
*reg
;
99 enum cfa_how_kind cfa_how
;
100 const gdb_byte
*cfa_exp
;
102 /* Used to implement DW_CFA_remember_state. */
103 struct dwarf2_frame_state_reg_info
*prev
;
106 /* Structure describing a frame state. */
108 struct dwarf2_frame_state
110 /* Each register save state can be described in terms of a CFA slot,
111 another register, or a location expression. */
112 struct dwarf2_frame_state_reg_info regs
;
114 /* The PC described by the current frame state. */
117 /* Initial register set from the CIE.
118 Used to implement DW_CFA_restore. */
119 struct dwarf2_frame_state_reg_info initial
;
121 /* The information we care about from the CIE. */
124 ULONGEST retaddr_column
;
126 /* Flags for known producer quirks. */
128 /* The ARM compilers, in DWARF2 mode, assume that DW_CFA_def_cfa
129 and DW_CFA_def_cfa_offset takes a factored offset. */
130 int armcc_cfa_offsets_sf
;
132 /* The ARM compilers, in DWARF2 or DWARF3 mode, may assume that
133 the CFA is defined as REG - OFFSET rather than REG + OFFSET. */
134 int armcc_cfa_offsets_reversed
;
137 /* Set the architecture-specific register state initialization
138 function for GDBARCH to INIT_REG. */
140 extern void dwarf2_frame_set_init_reg (struct gdbarch
*gdbarch
,
141 void (*init_reg
) (struct gdbarch
*, int,
142 struct dwarf2_frame_state_reg
*,
143 struct frame_info
*));
145 /* Set the architecture-specific signal trampoline recognition
146 function for GDBARCH to SIGNAL_FRAME_P. */
149 dwarf2_frame_set_signal_frame_p (struct gdbarch
*gdbarch
,
150 int (*signal_frame_p
) (struct gdbarch
*,
151 struct frame_info
*));
153 /* Set the architecture-specific adjustment of .eh_frame and .debug_frame
157 dwarf2_frame_set_adjust_regnum (struct gdbarch
*gdbarch
,
158 int (*adjust_regnum
) (struct gdbarch
*,
161 /* Append the DWARF-2 frame unwinders to GDBARCH's list. */
163 void dwarf2_append_unwinders (struct gdbarch
*gdbarch
);
165 /* Return the frame base methods for the function that contains PC, or
166 NULL if it can't be handled by the DWARF CFI frame unwinder. */
168 extern const struct frame_base
*
169 dwarf2_frame_base_sniffer (struct frame_info
*this_frame
);
171 /* Compute the DWARF CFA for a frame. */
173 CORE_ADDR
dwarf2_frame_cfa (struct frame_info
*this_frame
);
175 /* Assert that the register set RS is large enough to store gdbarch_num_regs
176 columns. If necessary, enlarge the register set. */
178 void dwarf2_frame_state_alloc_regs (struct dwarf2_frame_state_reg_info
*rs
,
181 /* Find the CFA information for PC.
183 Return 1 if a register is used for the CFA, or 0 if another
184 expression is used. Throw an exception on error.
186 GDBARCH is the architecture to use.
187 DATA is the per-CU data.
189 REGNUM_OUT is an out parameter that is set to the register number.
190 OFFSET_OUT is the offset to use from this register.
191 These are only filled in when 1 is returned.
193 TEXT_OFFSET_OUT, CFA_START_OUT, and CFA_END_OUT describe the CFA
194 in other cases. These are only used when 0 is returned. */
196 extern int dwarf2_fetch_cfa_info (struct gdbarch
*gdbarch
, CORE_ADDR pc
,
197 struct dwarf2_per_cu_data
*data
,
198 int *regnum_out
, LONGEST
*offset_out
,
199 CORE_ADDR
*text_offset_out
,
200 const gdb_byte
**cfa_start_out
,
201 const gdb_byte
**cfa_end_out
);
203 #endif /* dwarf2-frame.h */