1 /* Special .init and .fini section support.
2 Copyright (C) 1995, 1996, 1997, 2000 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
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.
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.)
19 The GNU C Library is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
22 Lesser General Public License for more details.
24 You should have received a copy of the GNU Lesser General Public
25 License along with the GNU C Library; if not, write to the Free
26 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
29 /* This file is compiled into assembly code which is then munged by a sed
30 script into two files: crti.s and crtn.s.
32 * crti.s puts a function prologue at the beginning of the
33 .init and .fini sections and defines global symbols for
34 those addresses, so they can be called as functions.
36 * crtn.s puts the corresponding function epilogues
37 in the .init and .fini sections. */
43 /* We use embedded asm for .section unconditionally, as this makes it
44 easier to insert the necessary directives into crtn.S. */
45 #define SECTION(x) asm (".section " x );
47 /* Declare symbols as hidden. Hidden symbols are only seen by
48 * the link editor and not by the dynamic loader. */
49 #ifdef __HAVE_DOT_HIDDEN__
50 # define HIDDEN(func) asm (".hidden " #func );
55 /* The initial common code ends here. */
56 asm ("\n/*@HEADER_ENDS*/");
58 /* To determine whether we need .end and .align: */
59 //asm ("\n/*@TESTS_BEGIN*/");
60 extern void dummy (void (*foo) (void));
62 dummy (void (*foo) (void))
67 //asm ("\n/*@TESTS_END*/");
69 /* The beginning of _init: */
70 asm ("\n/*@_init_PROLOG_BEGINS*/");
76 extern void __gmon_start__ (void) __attribute__ ((weak)); /*weak_extern (__gmon_start__);*/
77 void (*gmon_start) (void) = __gmon_start__;
87 extern void i_am_not_a_leaf (void);
88 extern void _init (void);
92 /* We cannot use the normal constructor mechanism in gcrt1.o because it
93 appears before crtbegin.o in the link, so the header elt of .ctors
94 would come after the elt for __gmon_start__. One approach is for
95 gcrt1.o to reference a symbol which would be defined by some library
96 module which has a constructor; but then user code's constructors
97 would come first, and not be profiled. */
100 asm ("\n/*@_init_PROLOG_PAUSES*/");
102 /* Let GCC know that _init is not a leaf function by having a dummy
103 * function call here. We arrange for this call to be omitted from
104 * either crt file. */
107 asm ("\n/*@_init_PROLOG_UNPAUSES*/");
112 /* Now the epilog. */
113 asm ("\n/*@_init_PROLOG_ENDS*/");
114 asm ("\n/*@_init_EPILOG_BEGINS*/");
117 /* End of the _init epilog, beginning of the _fini prolog. */
118 asm ("\n/*@_init_EPILOG_ENDS*/");
119 asm ("\n/*@_fini_PROLOG_BEGINS*/");
124 extern void i_am_not_a_leaf2 (void);
125 extern void _fini (void);
129 /* End of the _fini prolog. */
132 asm ("\n/*@_fini_PROLOG_ENDS*/");
135 /* Let GCC know that _fini is not a leaf function by having a dummy
136 function call here. We arrange for this call to be omitted from
141 /* Beginning of the _fini epilog. */
142 asm ("\n/*@_fini_EPILOG_BEGINS*/");
145 /* End of the _fini epilog. Any further generated assembly (e.g. .ident)
146 is shared between both crt files. */
147 asm ("\n/*@_fini_EPILOG_ENDS*/");
148 asm ("\n/*@TRAILER_BEGINS*/");