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/* Special .init and .fini section support.
Copyright (C) 1995, 1996, 1997, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
/* This file is compiled into assembly code which is then munged by a sed
script into two files: crti.s and crtn.s.
* crti.s puts a function prologue at the beginning of the
.init and .fini sections and defines global symbols for
those addresses, so they can be called as functions.
* crtn.s puts the corresponding function epilogues
in the .init and .fini sections. */
#include <stdlib.h>
/* We use embedded asm for .section unconditionally, as this makes it
easier to insert the necessary directives into crtn.S. */
#define SECTION(x) asm (".section " x )
/* Embed an #include to pull in the alignment and .end directives. */
asm ("\n#include \"defs.h\"");
/* The initial common code ends here. */
asm ("\n/*@HEADER_ENDS*/");
/* To determine whether we need .end and .align: */
asm ("\n/*@TESTS_BEGIN*/");
extern void dummy (void (*foo) (void));
void
dummy (void (*foo) (void))
{
if (foo)
(*foo) ();
}
asm ("\n/*@TESTS_END*/");
/* The beginning of _init: */
asm ("\n/*@_init_PROLOG_BEGINS*/");
static void
call_gmon_start(void)
{
extern void __gmon_start__ (void) __attribute__ ((weak)); /*weak_extern (__gmon_start__);*/
void (*gmon_start) (void) = __gmon_start__;
if (gmon_start)
gmon_start ();
}
SECTION (".init");
extern void _init (void);
void
_init (void)
{
/* We cannot use the normal constructor mechanism in gcrt1.o because it
appears before crtbegin.o in the link, so the header elt of .ctors
would come after the elt for __gmon_start__. One approach is for
gcrt1.o to reference a symbol which would be defined by some library
module which has a constructor; but then user code's constructors
would come first, and not be profiled. */
call_gmon_start ();
asm ("ALIGN");
asm("END_INIT");
/* Now the epilog. */
asm ("\n/*@_init_PROLOG_ENDS*/");
asm ("\n/*@_init_EPILOG_BEGINS*/");
SECTION(".init");
}
asm ("END_INIT");
/* End of the _init epilog, beginning of the _fini prolog. */
asm ("\n/*@_init_EPILOG_ENDS*/");
asm ("\n/*@_fini_PROLOG_BEGINS*/");
SECTION (".fini");
extern void _fini (void);
void
_fini (void)
{
/* End of the _fini prolog. */
asm ("ALIGN");
asm ("END_FINI");
asm ("\n/*@_fini_PROLOG_ENDS*/");
{
/* Let GCC know that _fini is not a leaf function by having a dummy
function call here. We arrange for this call to be omitted from
either crt file. */
extern void i_am_not_a_leaf (void);
i_am_not_a_leaf ();
}
/* Beginning of the _fini epilog. */
asm ("\n/*@_fini_EPILOG_BEGINS*/");
SECTION (".fini");
}
asm ("END_FINI");
/* End of the _fini epilog. Any further generated assembly (e.g. .ident)
is shared between both crt files. */
asm ("\n/*@_fini_EPILOG_ENDS*/");
asm ("\n/*@TRAILER_BEGINS*/");
/* End of file. */
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