| /* 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. |
| |
| In addition to the permissions in the GNU Lesser General Public |
| License, the Free Software Foundation gives you unlimited |
| permission to link the compiled version of this file with other |
| programs, and to distribute those programs without any restriction |
| coming from the use of this file. (The GNU Lesser General Public |
| License restrictions do apply in other respects; for example, they |
| cover modification of the file, and distribution when not linked |
| into another program.) |
| |
| Note that people who make modified versions of this file are not |
| obligated to grant this special exception for their modified |
| versions; it is their choice whether to do so. The GNU Lesser |
| General Public License gives permission to release a modified |
| version without this exception; this exception also makes it |
| possible to release a modified version which carries forward this |
| exception. |
| |
| 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 __attribute__ ((section (".init"))) _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 __attribute__ ((section (".fini"))) _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. */ |