freebsd-dev/sys/sys/linker_set.h
1999-08-28 01:08:13 +00:00

86 lines
3.0 KiB
C

/*-
* Copyright (c) 1999 John D. Polstra
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _SYS_LINKER_SET_H_
#define _SYS_LINKER_SET_H_
/*
* The following macros are used to declare global sets of objects, which
* are collected by the linker into a `struct linker_set' as defined below.
* For ELF, this is done by constructing a separate segment for each set.
* For a.out, it is done automatically by the linker.
*/
#ifdef __ELF__
/*
* Alpha GAS needs an align before the section change. It seems to assume
* that after the .previous, it is aligned, so the following .align 3 is
* ignored. Since the previous instructions often contain strings, this is
* a problem.
*/
#ifdef __alpha__
#define MAKE_SET(set, sym) \
static void const * const __set_##set##_sym_##sym = &sym; \
__asm(".align 3"); \
__asm(".section .set." #set ",\"aw\""); \
__asm(".quad " #sym); \
__asm(".previous")
#else
#define MAKE_SET(set, sym) \
static void const * const __set_##set##_sym_##sym = &sym; \
__asm(".section .set." #set ",\"aw\""); \
__asm(".long " #sym); \
__asm(".previous")
#endif
#define TEXT_SET(set, sym) MAKE_SET(set, sym)
#define DATA_SET(set, sym) MAKE_SET(set, sym)
#else
/*
* NB: the constants defined below must match those defined in
* ld/ld.h. Since their calculation requires arithmetic, we
* can't name them symbolically (e.g., 23 is N_SETT | N_EXT).
*/
#define MAKE_SET(set, sym, type) \
static void const * const __set_##set##_sym_##sym = &sym; \
__asm(".stabs \"_" #set "\", " #type ", 0, 0, _" #sym)
#define TEXT_SET(set, sym) MAKE_SET(set, sym, 23)
#define DATA_SET(set, sym) MAKE_SET(set, sym, 25)
#endif
struct linker_set {
int ls_length;
void *ls_items[1]; /* really ls_length of them,
* trailing NULL */
};
#endif /* _SYS_LINKER_SET_H_ */