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/tmp/gdb-8.1/gdb/macroscope.c
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1 /* Functions for deciding which macros are currently in scope.
2 Copyright (C) 2002-2018 Free Software Foundation, Inc.
3 Contributed by Red Hat, Inc.
4
5 This file is part of GDB.
6
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 3 of the License, or
10 (at your option) any later version.
11
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.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19
20 #include "defs.h"
21
22 #include "macroscope.h"
23 #include "symtab.h"
24 #include "source.h"
25 #include "target.h"
26 #include "frame.h"
27 #include "inferior.h"
28 #include "complaints.h"
29
30 /* A table of user-defined macros. Unlike the macro tables used for
31 symtabs, this one uses xmalloc for all its allocation, not an
32 obstack, and it doesn't bcache anything; it just xmallocs things. So
33 it's perfectly possible to remove things from this, or redefine
34 things. */
35 struct macro_table *macro_user_macros;
36
37
38 struct macro_scope *
39 sal_macro_scope (struct symtab_and_line sal)
40 {
41 struct macro_source_file *main_file, *inclusion;
42 struct macro_scope *ms;
43 struct compunit_symtab *cust;
44
45 if (sal.symtab == NULL)
46 return NULL;
47 cust = SYMTAB_COMPUNIT (sal.symtab);
48 if (COMPUNIT_MACRO_TABLE (cust) == NULL)
49 return NULL;
50
51 ms = XNEW (struct macro_scope);
52
53 main_file = macro_main (COMPUNIT_MACRO_TABLE (cust));
54 inclusion = macro_lookup_inclusion (main_file, sal.symtab->filename);
55
56 if (inclusion)
57 {
58 ms->file = inclusion;
59 ms->line = sal.line;
60 }
61 else
62 {
63 /* There are, unfortunately, cases where a compilation unit can
64 have a symtab for a source file that doesn't appear in the
65 macro table. For example, at the moment, Dwarf doesn't have
66 any way in the .debug_macinfo section to describe the effect
67 of #line directives, so if you debug a YACC parser you'll get
68 a macro table which only mentions the .c files generated by
69 YACC, but symtabs that mention the .y files consumed by YACC.
70
71 In the long run, we should extend the Dwarf macro info
72 representation to handle #line directives, and get GCC to
73 emit it.
74
75 For the time being, though, we'll just treat these as
76 occurring at the end of the main source file. */
77 ms->file = main_file;
78 ms->line = -1;
79
80 complaint (&symfile_complaints,
81 _("symtab found for `%s', but that file\n"
82 "is not covered in the compilation unit's macro information"),
83 symtab_to_filename_for_display (sal.symtab));
84 }
85
86 return ms;
87 }
88
89
90 struct macro_scope *
91 user_macro_scope (void)
92 {
93 struct macro_scope *ms;
94
95 ms = XNEW (struct macro_scope);
96 ms->file = macro_main (macro_user_macros);
97 ms->line = -1;
98 return ms;
99 }
100
101 struct macro_scope *
102 default_macro_scope (void)
103 {
104 struct symtab_and_line sal;
105 struct macro_scope *ms;
106 struct frame_info *frame;
107 CORE_ADDR pc;
108
109 /* If there's a selected frame, use its PC. */
110 frame = deprecated_safe_get_selected_frame ();
111 if (frame && get_frame_pc_if_available (frame, &pc))
112 sal = find_pc_line (pc, 0);
113
114 /* Fall back to the current listing position. */
115 else
116 {
117 /* Don't call select_source_symtab here. That can raise an
118 error if symbols aren't loaded, but GDB calls the expression
119 evaluator in all sorts of contexts.
120
121 For example, commands like `set width' call the expression
122 evaluator to evaluate their numeric arguments. If the
123 current language is C, then that may call this function to
124 choose a scope for macro expansion. If you don't have any
125 symbol files loaded, then get_current_or_default would raise an
126 error. But `set width' shouldn't raise an error just because
127 it can't decide which scope to macro-expand its argument in. */
128 struct symtab_and_line cursal =
129 get_current_source_symtab_and_line ();
130
131 sal.symtab = cursal.symtab;
132 sal.line = cursal.line;
133 }
134
135 ms = sal_macro_scope (sal);
136 if (! ms)
137 ms = user_macro_scope ();
138
139 return ms;
140 }
141
142
143 /* Look up the definition of the macro named NAME in scope at the source
144 location given by BATON, which must be a pointer to a `struct
145 macro_scope' structure. */
146 struct macro_definition *
147 standard_macro_lookup (const char *name, void *baton)
148 {
149 struct macro_scope *ms = (struct macro_scope *) baton;
150 struct macro_definition *result;
151
152 /* Give user-defined macros priority over all others. */
153 result = macro_lookup_definition (macro_main (macro_user_macros), -1, name);
154 if (! result)
155 result = macro_lookup_definition (ms->file, ms->line, name);
156 return result;
157 }
158
159 void
160 _initialize_macroscope (void)
161 {
162 macro_user_macros = new_macro_table (NULL, NULL, NULL);
163 macro_set_main (macro_user_macros, "<user-defined>");
164 macro_allow_redefinitions (macro_user_macros);
165 }
symtab_to_filename_for_display
const char * symtab_to_filename_for_display(struct symtab *symtab)
Definition: source.c:1168
macro_source_file
Definition: macrotab.h:124
SYMTAB_COMPUNIT
#define SYMTAB_COMPUNIT(symtab)
Definition: symtab.h:1331
macro_scope::file
struct macro_source_file * file
Definition: macroscope.h:34
CORE_ADDR
bfd_vma CORE_ADDR
Definition: common-types.h:41
macro_scope
Definition: macroscope.h:33
macro_lookup_inclusion
struct macro_source_file * macro_lookup_inclusion(struct macro_source_file *source, const char *name)
Definition: macrotab.c:511
get_current_source_symtab_and_line
struct symtab_and_line get_current_source_symtab_and_line(void)
Definition: source.c:171
COMPUNIT_MACRO_TABLE
#define COMPUNIT_MACRO_TABLE(cust)
Definition: symtab.h:1470
standard_macro_lookup
struct macro_definition * standard_macro_lookup(const char *name, void *baton)
Definition: macroscope.c:147
get_frame_pc_if_available
int get_frame_pc_if_available(struct frame_info *frame, CORE_ADDR *pc)
Definition: frame.c:2383
frame_info
Definition: frame.c:85
compunit_symtab
Definition: symtab.h:1380
symtab::filename
const char * filename
Definition: symtab.h:1309
_
#define _(String)
Definition: gdb_locale.h:35
sal_macro_scope
struct macro_scope * sal_macro_scope(struct symtab_and_line sal)
Definition: macroscope.c:39
defs.h
macro_table
Definition: macrotab.c:35
default_macro_scope
struct macro_scope * default_macro_scope(void)
Definition: macroscope.c:102
macroscope.h
macro_user_macros
struct macro_table * macro_user_macros
Definition: macroscope.c:35
XNEW
#define XNEW(T)
Definition: poison.h:109
symtab.h
name
const char *const name
Definition: aarch64-tdep.c:76
find_pc_line
struct symtab_and_line find_pc_line(CORE_ADDR pc, int notcurrent)
Definition: symtab.c:3288
macro_definition
Definition: macrotab.h:288
macro_lookup_definition
struct macro_definition * macro_lookup_definition(struct macro_source_file *source, int line, const char *name)
Definition: macrotab.c:922
frame.h
inferior.h
deprecated_safe_get_selected_frame
struct frame_info * deprecated_safe_get_selected_frame(void)
Definition: frame.c:1667
complaint
#define complaint(COMPLAINTS, FMT,...)
Definition: complaints.h:40
symtab_and_line::symtab
struct symtab * symtab
Definition: symtab.h:1751
complaints.h
_initialize_macroscope
void _initialize_macroscope(void)
Definition: macroscope.c:160
symtab_and_line
Definition: symtab.h:1746
source.h
symfile_complaints
struct complaints * symfile_complaints
Definition: complaints.c:96
macro_scope::line
int line
Definition: macroscope.h:35
target.h
macro_set_main
struct macro_source_file * macro_set_main(struct macro_table *t, const char *filename)
Definition: macrotab.c:419
macro_allow_redefinitions
void macro_allow_redefinitions(struct macro_table *t)
Definition: macrotab.c:442
macro_main
struct macro_source_file * macro_main(struct macro_table *t)
Definition: macrotab.c:433
symtab_and_line::line
int line
Definition: symtab.h:1757
new_macro_table
struct macro_table * new_macro_table(struct obstack *obstack, struct bcache *b, struct compunit_symtab *cust)
Definition: macrotab.c:1048
user_macro_scope
struct macro_scope * user_macro_scope(void)
Definition: macroscope.c:91