xref: /openbsd/gnu/usr.bin/binutils/gdb/frame.h (revision 78b63d65)
1 /* Definitions for dealing with stack frames, for GDB, the GNU debugger.
2    Copyright 1986, 1989, 1991, 1992 Free Software Foundation, Inc.
3 
4 This file is part of GDB.
5 
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10 
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 GNU General Public License for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
19 
20 #if !defined (FRAME_H)
21 #define FRAME_H 1
22 
23 /* Describe the saved registers of a frame.  */
24 
25 struct frame_saved_regs
26   {
27 
28     /* For each register, address of where it was saved on entry to
29        the frame, or zero if it was not saved on entry to this frame.
30        This includes special registers such as pc and fp saved in
31        special ways in the stack frame.  The SP_REGNUM is even more
32        special, the address here is the sp for the next frame, not the
33        address where the sp was saved.  */
34 
35     CORE_ADDR regs[NUM_REGS];
36   };
37 
38 /* We keep a cache of stack frames, each of which is a "struct
39    frame_info".  The innermost one gets allocated (in
40    wait_for_inferior) each time the inferior stops; current_frame
41    points to it.  Additional frames get allocated (in
42    get_prev_frame_info) as needed, and are chained through the next
43    and prev fields.  Any time that the frame cache becomes invalid
44    (most notably when we execute something, but also if we change how
45    we interpret the frames (e.g. "set heuristic-fence-post" in
46    mips-tdep.c, or anything which reads new symbols)), we should call
47    reinit_frame_cache.  */
48 
49 struct frame_info
50   {
51     /* Nominal address of the frame described.  See comments at FRAME_FP
52        about what this means outside the *FRAME* macros; in the *FRAME*
53        macros, it can mean whatever makes most sense for this machine.  */
54     CORE_ADDR frame;
55 
56     /* Address at which execution is occurring in this frame.
57        For the innermost frame, it's the current pc.
58        For other frames, it is a pc saved in the next frame.  */
59     CORE_ADDR pc;
60 
61     /* Nonzero if this is a frame associated with calling a signal handler.
62 
63        Set by machine-dependent code.  On some machines, if
64        the machine-dependent code fails to check for this, the backtrace
65        will look relatively normal.  For example, on the i386
66          #3  0x158728 in sighold ()
67        On other machines (e.g. rs6000), the machine-dependent code better
68        set this to prevent us from trying to print it like a normal frame.  */
69     int signal_handler_caller;
70 
71     /* Anything extra for this structure that may have been defined
72        in the machine dependent files. */
73 #ifdef EXTRA_FRAME_INFO
74     EXTRA_FRAME_INFO
75 #endif
76 
77     /* We should probably also store a "struct frame_saved_regs" here.
78        This is already done by some machines (e.g. config/m88k/tm-m88k.h)
79        but there is no reason it couldn't be general.  */
80 
81     /* Pointers to the next and previous frame_info's in the frame cache.  */
82    struct frame_info *next, *prev;
83   };
84 
85 /* Return the frame address from FR.  Except in the machine-dependent
86    *FRAME* macros, a frame address has no defined meaning other than
87    as a magic cookie which identifies a frame over calls to the
88    inferior.  The only known exception is inferior.h
89    (PC_IN_CALL_DUMMY) [ON_STACK]; see comments there.  You cannot
90    assume that a frame address contains enough information to
91    reconstruct the frame; if you want more than just to identify the
92    frame (e.g. be able to fetch variables relative to that frame),
93    then save the whole struct frame_info (and the next struct
94    frame_info, since the latter is used for fetching variables on some
95    machines).  */
96 
97 #define FRAME_FP(fi) ((fi)->frame)
98 
99 /* Define a default FRAME_CHAIN_VALID, in the form that is suitable for most
100    targets.  If FRAME_CHAIN_VALID returns zero it means that the given frame
101    is the outermost one and has no caller.
102 
103    If a particular target needs a different definition, then it can override
104    the definition here by providing one in the tm file. */
105 
106 #if !defined (FRAME_CHAIN_VALID)
107 
108 #if defined (FRAME_CHAIN_VALID_ALTERNATE)
109 
110 /* Use the alternate method of avoiding running up off the end of the frame
111    chain or following frames back into the startup code.  See the comments
112    in objfiles.h. */
113 
114 #define FRAME_CHAIN_VALID(chain, thisframe)	\
115   ((chain) != 0					\
116    && !inside_main_func ((thisframe) -> pc)	\
117    && !inside_entry_func ((thisframe) -> pc))
118 
119 #else
120 
121 #define FRAME_CHAIN_VALID(chain, thisframe)	\
122   ((chain) != 0					\
123    && !inside_entry_file (FRAME_SAVED_PC (thisframe)))
124 
125 #endif	/* FRAME_CHAIN_VALID_ALTERNATE */
126 
127 #endif	/* FRAME_CHAIN_VALID */
128 
129 /* The stack frame that the user has specified for commands to act on.
130    Note that one cannot assume this is the address of valid data.  */
131 
132 extern struct frame_info *selected_frame;
133 
134 /* Level of the selected frame:
135    0 for innermost, 1 for its caller, ...
136    or -1 for frame specified by address with no defined level.  */
137 
138 extern int selected_frame_level;
139 
140 extern struct frame_info *get_prev_frame_info PARAMS ((struct frame_info *));
141 
142 extern struct frame_info *create_new_frame PARAMS ((CORE_ADDR, CORE_ADDR));
143 
144 extern void flush_cached_frames PARAMS ((void));
145 
146 extern void reinit_frame_cache PARAMS ((void));
147 
148 extern void get_frame_saved_regs PARAMS ((struct frame_info *,
149 					  struct frame_saved_regs *));
150 
151 extern void set_current_frame PARAMS ((struct frame_info *));
152 
153 extern struct frame_info *get_prev_frame PARAMS ((struct frame_info *));
154 
155 extern struct frame_info *get_current_frame PARAMS ((void));
156 
157 extern struct frame_info *get_next_frame PARAMS ((struct frame_info *));
158 
159 extern struct block *get_frame_block PARAMS ((struct frame_info *));
160 
161 extern struct block *get_current_block PARAMS ((void));
162 
163 extern struct block *get_selected_block PARAMS ((void));
164 
165 extern struct symbol *get_frame_function PARAMS ((struct frame_info *));
166 
167 extern CORE_ADDR get_frame_pc PARAMS ((struct frame_info *));
168 
169 extern CORE_ADDR get_pc_function_start PARAMS ((CORE_ADDR));
170 
171 extern struct block * block_for_pc PARAMS ((CORE_ADDR));
172 
173 extern int frameless_look_for_prologue PARAMS ((struct frame_info *));
174 
175 extern void print_frame_args PARAMS ((struct symbol *, struct frame_info *,
176 				      int, GDB_FILE *));
177 
178 extern struct frame_info *find_relative_frame PARAMS ((struct frame_info *, int*));
179 
180 extern void print_stack_frame PARAMS ((struct frame_info *, int, int));
181 
182 extern void select_frame PARAMS ((struct frame_info *, int));
183 
184 extern void record_selected_frame PARAMS ((CORE_ADDR *, int *));
185 
186 extern void print_frame_info PARAMS ((struct frame_info *, int, int, int));
187 
188 extern CORE_ADDR find_saved_register PARAMS ((struct frame_info *, int));
189 
190 extern struct frame_info *block_innermost_frame PARAMS ((struct block *));
191 
192 extern struct frame_info *find_frame_addr_in_frame_chain PARAMS ((CORE_ADDR));
193 
194 extern CORE_ADDR sigtramp_saved_pc PARAMS ((struct frame_info *));
195 
196 #endif /* !defined (FRAME_H)  */
197