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author | Ulrich Drepper <drepper@redhat.com> | 1997-04-18 00:20:23 +0000 |
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committer | Ulrich Drepper <drepper@redhat.com> | 1997-04-18 00:20:23 +0000 |
commit | 307bcd77838a5546a4fa65e7a88258a6ea78898c (patch) | |
tree | a0df3b4ed5d08f34b204955332c533c0114ee407 /csu/initfini.c | |
parent | dd33e89fb2693e88ba64e6b947184c5abf70ff00 (diff) | |
download | glibc-307bcd77838a5546a4fa65e7a88258a6ea78898c.zip glibc-307bcd77838a5546a4fa65e7a88258a6ea78898c.tar.gz glibc-307bcd77838a5546a4fa65e7a88258a6ea78898c.tar.bz2 |
Rewrite by Zack Weinberg.cvs/libc-ud-970417
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.
Diffstat (limited to 'csu/initfini.c')
-rw-r--r-- | csu/initfini.c | 127 |
1 files changed, 48 insertions, 79 deletions
diff --git a/csu/initfini.c b/csu/initfini.c index 0fdfe5d..96ee7bc 100644 --- a/csu/initfini.c +++ b/csu/initfini.c @@ -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"))); - -#define SECTION(x) /* Put nothing extra before the defn. */ - -#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 +/* Embed an #include to pull in the alignment and .end directives. */ +asm ("\n#include \"defs.h\""); -/* 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"); -void -useless_function (void) -{ - return; -} -asm ("\nEOF.end\n"); +/* The initial common code ends here. */ +asm ("\n/*@HEADER_ENDS*/"); -/* Find out how much alignment is produced by the compiler. */ -asm ("align=`awk '$1==\".align\" { if ($2>max) max=$2; } END { print max; }' \ -<<\\EOF.align"); +/* To determine whether we need .end and .align: */ +asm ("\n/*@TESTS_BEGIN*/"); void -useless_function2 (void (*foo) (void)) +dummy (void (*foo) (void)) { if (foo) (*foo) (); } -asm ("\nEOF.align\n`\n"); +asm ("\n/*@TESTS_END*/"); -/* Append the .init prologue to crti.s-new. */ -asm ("cat >> crti.s-new <<\\EOF.crti.init"); +/* The beginning of _init: */ +asm ("\n/*@_init_PROLOG_BEGINS*/"); SECTION (".init") void @@ -99,38 +71,32 @@ _init (void) gcrt1.o to reference a symbol which would be defined by some library module which has a constructor; but then user code's constructors would come first, and not be profiled. */ - extern void __gmon_start__ (void); weak_extern (__gmon_start__) + extern void __gmon_start__ (void) __attribute__ ((weak)); /*weak_extern (__gmon_start__);*/ + if (__gmon_start__) __gmon_start__ (); - /* End the here document containing the .init prologue code. - Then fetch the .section directive just written and append that - to crtn.s-new, followed by the function epilogue. */ - asm ("\n\ -EOF.crti.init\n\ - test -n \"$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 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 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 file. */ |