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Rewrite by Zack Weinberg.

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1997-04-18 02:18  Ulrich Drepper  <drepper@cygnus.com>

	* csu/initfini.c: Rewrite by Zack Weinberg
	<zack@rabi.phys.columbia.edu>.
	* csu/Makefile: Add rules for rewrite.
	* csu/defs.awk: Helper script to generate derived header.
This commit is contained in:
Ulrich Drepper
1997-04-18 00:20:23 +00:00
parent dd33e89fb2
commit 307bcd7783
4 changed files with 99 additions and 99 deletions
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127
csu/initfini.c
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@ -1,5 +1,5 @@
/* Special .init and .fini section support.
Copyright (C) 1995, 1996 Free Software Foundation, Inc.
Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it
@ -26,68 +26,40 @@
write to the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
/* This file is compiled into assembly code which is then surrounded by the
lines `cat > crtcommon.tmp <<\EOF_common' and `EOF_common' and thus
becomes a shell script which creates three files of assembly code.
/* This file is compiled into assembly code which is then munged by a sed
script into two files: crti.s and crtn.s.
* The first file is crti.s-new; this puts a function prologue at the
beginning of the .init and .fini sections and defines global symbols for
* 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.
* The second file is crtn.s-new; this puts the corresponding function
epilogues in the .init and .fini sections.
* The third file is crtcommon.tmp, which is whatever miscellaneous cruft
the compiler generated at the end; it should be appended to both crti.s-new
and crtn.s-new. */
* 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 "\"");
#ifdef HAVE_ELF
/* These declarations make the functions go in the right sections when
we define them below. GCC syntax does not allow the attribute
specifications to be in the function definitions themselves. */
void _init (void) __attribute__ ((section (".init")));
void _fini (void) __attribute__ ((section (".fini")));
/* Embed an #include to pull in the alignment and .end directives. */
asm ("\n#include \"defs.h\"");
#define SECTION(x) /* Put nothing extra before the defn. */
/* The initial common code ends here. */
asm ("\n/*@HEADER_ENDS*/");
#else
/* Some non-ELF systems support .init and .fini sections,
but the __attribute__ syntax only works for ELF. */
#define SECTION(x) asm (".section " x);
#endif
/* End the here document containing the initial common code.
Then move the output file crtcommon.tmp to crti.s-new and crtn.s-new. */
asm ("\nEOF_common\n\
rm -f crti.s-new crtn.s-new\n\
mv crtcommon.tmp crti.s-new\n\
cp crti.s-new crtn.s-new");
/* Extract a `.end' if one is produced by the compiler. */
asm ("fgrep .end >/dev/null 2>&1 <<\\EOF.end && need_end=yes");
/* To determine whether we need .end and .align: */
asm ("\n/*@TESTS_BEGIN*/");
void
useless_function (void)
{
return;
}
asm ("\nEOF.end\n");
/* Find out how much alignment is produced by the compiler. */
asm ("align=`awk '$1==\".align\" { if ($2>max) max=$2; } END { print max; }' \
<<\\EOF.align");
void
useless_function2 (void (*foo) (void))
dummy (void (*foo) (void))
{
if (foo)
(*foo) ();
}
asm ("\nEOF.align\n`\n");
asm ("\n/*@TESTS_END*/");
/* Append the .init prologue to crti.s-new. */
asm ("cat >> crti.s-new <<\\EOF.crti.init");
/* The beginning of _init: */
asm ("\n/*@_init_PROLOG_BEGINS*/");
SECTION (".init")
void
@ -99,38 +71,32 @@ _init (void)
gcrt1.o to reference a symbol which would be defined by some library
module which has a constructor; but then user code's constructors
would come first, and not be profiled. */
extern void __gmon_start__ (void); weak_extern (__gmon_start__)
extern void __gmon_start__ (void) __attribute__ ((weak)); /*weak_extern (__gmon_start__);*/
if (__gmon_start__)
__gmon_start__ ();
/* End the here document containing the .init prologue code.
Then fetch the .section directive just written and append that
to crtn.s-new, followed by the function epilogue. */
asm ("\n\
EOF.crti.init\n\
test -n \"$align\" && echo .align $align >> crti.s-new\n\
test -n \"$need_end\" && echo .end _init >> crti.s-new\n\
fgrep .init crti.s-new >>crtn.s-new\n\
fgrep -v .end >> crtn.s-new <<\\EOF.crtn.init");
asm("END_INIT");
/* Now the epilog. */
asm ("\n/*@_init_PROLOG_ENDS*/");
asm ("\n/*@_init_EPILOG_BEGINS*/");
SECTION(".init");
asm ("ALIGN");
}
asm ("END_INIT");
/* End the here document containing the .init epilogue code.
Then append the .fini prologue to crti.s-new. */
asm ("\nEOF.crtn.init\
\n\
cat >> crti.s-new <<\\EOF.crti.fini");
/* End of the _init epilog, beginning of the _fini prolog. */
asm ("\n/*@_init_EPILOG_ENDS*/");
asm ("\n/*@_fini_PROLOG_BEGINS*/");
SECTION (".fini")
void
_fini (void)
{
/* End the here document containing the .fini prologue code.
Then fetch the .section directive just written and append that
to crtn.s-new, followed by the function epilogue. */
asm ("\nEOF.crti.fini\n\
test -n \"$align\" && echo .align $align >> crti.s-new\n\
test -n \"$need_end\" && echo .end _fini >> crti.s-new\n\
cat > /dev/null <<\\EOF.fini.skip");
/* End of the _fini prolog. */
asm ("END_FINI");
asm ("\n/*@_fini_PROLOG_ENDS*/");
{
/* Let GCC know that _fini is not a leaf function by having a dummy
@ -140,14 +106,17 @@ cat > /dev/null <<\\EOF.fini.skip");
i_am_not_a_leaf ();
}
asm ("\nEOF.fini.skip\
\n\
fgrep .fini crti.s-new >>crtn.s-new\n\
fgrep -v .end >> crtn.s-new <<\\EOF.crtn.fini");
/* Beginning of the _fini epilog. */
asm ("\n/*@_fini_EPILOG_BEGINS*/");
SECTION (".fini");
asm ("ALIGN");
}
asm ("END_FINI");
/* End the here document containing the .fini epilogue code.
Finally, put the remainder of the generated assembly into crtcommon.tmp. */
asm ("\nEOF.crtn.fini\
\n\
cat > crtcommon.tmp <<\\EOF_common");
/* 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*/");
asm ("ALIGN");
/* End of file. */