1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
|
/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 2012. All Rights Reserved.
*
* The contents of this file are subject to the Erlang Public License,
* Version 1.1, (the "License"); you may not use this file except in
* compliance with the License. You should have received a copy of the
* Erlang Public License along with this software. If not, it can be
* retrieved online at http://www.erlang.org/.
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
* the License for the specific language governing rights and limitations
* under the License.
*
* %CopyrightEnd%
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "sys.h"
#include "erl_vm.h"
#include "global.h"
#include "beam_load.h"
static void lookup_loc(FunctionInfo* fi, BeamInstr* pc,
BeamInstr* modp, int idx);
/*
* The following variables keep a sorted list of address ranges for
* each module. It allows us to quickly find a function given an
* instruction pointer.
*/
static Range* modules = NULL; /* Sorted lists of module addresses. */
static int num_loaded_modules; /* Number of loaded modules. */
static int allocated_modules; /* Number of slots allocated. */
static Range* mid_module = NULL; /* Cached search start point */
void
erts_init_ranges(void)
{
allocated_modules = 128;
modules = (Range *) erts_alloc(ERTS_ALC_T_MODULE_REFS,
allocated_modules*sizeof(Range));
mid_module = modules;
num_loaded_modules = 0;
}
void
erts_update_ranges(BeamInstr* code, Uint size)
{
int i;
if (num_loaded_modules == allocated_modules) {
allocated_modules *= 2;
modules = (Range *) erts_realloc(ERTS_ALC_T_MODULE_REFS,
(void *) modules,
allocated_modules * sizeof(Range));
}
for (i = num_loaded_modules; i > 0; i--) {
if (code > modules[i-1].start) {
break;
}
modules[i] = modules[i-1];
}
modules[i].start = code;
modules[i].end = (BeamInstr *) (((byte *)code) + size);
num_loaded_modules++;
mid_module = &modules[num_loaded_modules/2];
}
void
erts_remove_from_ranges(BeamInstr* code)
{
int i;
for (i = 0; i < num_loaded_modules; i++) {
if (modules[i].start == code) {
num_loaded_modules--;
while (i < num_loaded_modules) {
modules[i] = modules[i+1];
i++;
}
mid_module = &modules[num_loaded_modules/2];
return;
}
}
ASSERT(0); /* Not found? */
}
Uint
erts_ranges_sz(void)
{
return allocated_modules*sizeof(Range);
}
/*
* Find a function from the given pc and fill information in
* the FunctionInfo struct. If the full_info is non-zero, fill
* in all available information (including location in the
* source code). If no function is found, the 'current' field
* will be set to NULL.
*/
void
erts_lookup_function_info(FunctionInfo* fi, BeamInstr* pc, int full_info)
{
Range* low = modules;
Range* high = low + num_loaded_modules;
Range* mid = mid_module;
fi->current = NULL;
fi->needed = 5;
fi->loc = LINE_INVALID_LOCATION;
while (low < high) {
if (pc < mid->start) {
high = mid;
} else if (pc > mid->end) {
low = mid + 1;
} else {
BeamInstr** low1 = (BeamInstr **) (mid->start + MI_FUNCTIONS);
BeamInstr** high1 = low1 + mid->start[MI_NUM_FUNCTIONS];
BeamInstr** mid1;
while (low1 < high1) {
mid1 = low1 + (high1-low1) / 2;
if (pc < mid1[0]) {
high1 = mid1;
} else if (pc < mid1[1]) {
mid_module = mid;
fi->current = mid1[0]+2;
if (full_info) {
BeamInstr** fp = (BeamInstr **) (mid->start +
MI_FUNCTIONS);
int idx = mid1 - fp;
lookup_loc(fi, pc, mid->start, idx);
}
return;
} else {
low1 = mid1 + 1;
}
}
return;
}
mid = low + (high-low) / 2;
}
}
static void
lookup_loc(FunctionInfo* fi, BeamInstr* orig_pc, BeamInstr* modp, int idx)
{
Eterm* line = (Eterm *) modp[MI_LINE_TABLE];
Eterm* low;
Eterm* high;
Eterm* mid;
Eterm pc;
if (line == 0) {
return;
}
pc = (Eterm) (BeamInstr) orig_pc;
fi->fname_ptr = (Eterm *) (BeamInstr) line[MI_LINE_FNAME_PTR];
low = (Eterm *) (BeamInstr) line[MI_LINE_FUNC_TAB+idx];
high = (Eterm *) (BeamInstr) line[MI_LINE_FUNC_TAB+idx+1];
while (high > low) {
mid = low + (high-low) / 2;
if (pc < mid[0]) {
high = mid;
} else if (pc < mid[1]) {
int file;
int index = mid - (Eterm *) (BeamInstr) line[MI_LINE_FUNC_TAB];
if (line[MI_LINE_LOC_SIZE] == 2) {
Uint16* loc_table =
(Uint16 *) (BeamInstr) line[MI_LINE_LOC_TAB];
fi->loc = loc_table[index];
} else {
Uint32* loc_table =
(Uint32 *) (BeamInstr) line[MI_LINE_LOC_TAB];
ASSERT(line[MI_LINE_LOC_SIZE] == 4);
fi->loc = loc_table[index];
}
if (fi->loc == LINE_INVALID_LOCATION) {
return;
}
fi->needed += 3+2+3+2;
file = LOC_FILE(fi->loc);
if (file == 0) {
/* Special case: Module name with ".erl" appended */
Atom* mod_atom = atom_tab(atom_val(fi->current[0]));
fi->needed += 2*(mod_atom->len+4);
} else {
Atom* ap = atom_tab(atom_val((fi->fname_ptr)[file-1]));
fi->needed += 2*ap->len;
}
return;
} else {
low = mid + 1;
}
}
}
|
