1 | /* Code to enable profiling at program startup. |
2 | Copyright (C) 1995-2018 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | In addition to the permissions in the GNU Lesser General Public |
11 | License, the Free Software Foundation gives you unlimited |
12 | permission to link the compiled version of this file with other |
13 | programs, and to distribute those programs without any restriction |
14 | coming from the use of this file. (The GNU Lesser General Public |
15 | License restrictions do apply in other respects; for example, they |
16 | cover modification of the file, and distribution when not linked |
17 | into another program.) |
18 | |
19 | Note that people who make modified versions of this file are not |
20 | obligated to grant this special exception for their modified |
21 | versions; it is their choice whether to do so. The GNU Lesser |
22 | General Public License gives permission to release a modified |
23 | version without this exception; this exception also makes it |
24 | possible to release a modified version which carries forward this |
25 | exception. |
26 | |
27 | The GNU C Library is distributed in the hope that it will be useful, |
28 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
29 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
30 | Lesser General Public License for more details. |
31 | |
32 | You should have received a copy of the GNU Lesser General Public |
33 | License along with the GNU C Library; if not, see |
34 | <http://www.gnu.org/licenses/>. */ |
35 | |
36 | #include <sys/types.h> |
37 | #include <sys/gmon.h> |
38 | #include <stdlib.h> |
39 | #include <unistd.h> |
40 | #define __ASSEMBLY__ |
41 | #include <entry.h> |
42 | |
43 | /* Beginning and end of our code segment. We cannot declare them |
44 | as the external functions since we want the addresses of those |
45 | labels. Taking the address of a function may have different |
46 | meanings on different platforms. */ |
47 | #ifdef ENTRY_POINT_DECL |
48 | ENTRY_POINT_DECL(extern) |
49 | #else |
50 | extern char ENTRY_POINT[]; |
51 | #endif |
52 | extern char etext[]; |
53 | |
54 | #ifndef TEXT_START |
55 | # ifdef ENTRY_POINT_DECL |
56 | # define TEXT_START ENTRY_POINT |
57 | # else |
58 | # define TEXT_START &ENTRY_POINT |
59 | # endif |
60 | #endif |
61 | |
62 | #ifdef GMON_START_ARRAY_SECTION |
63 | static void __gmon_start__ (void); |
64 | static void (*const gmon_start_initializer) (void) |
65 | __attribute__ ((used, section (GMON_START_ARRAY_SECTION))) = &__gmon_start__; |
66 | static |
67 | #else |
68 | /* We cannot use the normal constructor mechanism to call |
69 | __gmon_start__ because gcrt1.o appears before crtbegin.o in the link. |
70 | Instead crti.o calls it specially. */ |
71 | extern void __gmon_start__ (void); |
72 | #endif |
73 | |
74 | void |
75 | __gmon_start__ (void) |
76 | { |
77 | /* Protect from being called more than once. Since crti.o is linked |
78 | into every shared library, each of their init functions will call us. */ |
79 | static int called; |
80 | |
81 | if (called) |
82 | return; |
83 | |
84 | called = 1; |
85 | |
86 | /* Start keeping profiling records. */ |
87 | __monstartup ((u_long) TEXT_START, (u_long) &etext); |
88 | |
89 | /* Call _mcleanup before exiting; it will write out gmon.out from the |
90 | collected data. */ |
91 | atexit (&_mcleanup); |
92 | } |
93 | |