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/* Copyright (C) 1991, 92, 93, 95, 96 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <sysdeps/unix/sysdep.h>
#ifdef ASSEMBLER
/* Syntactic details of assembler. */
#ifdef HAVE_ELF
/* ELF uses byte-counts for .align, most others use log2 of count of bytes. */
#define ALIGNARG(log2) 1<<log2
/* For ELF we need the `.type' directive to make shared libs work right. */
#define ASM_TYPE_DIRECTIVE(name,typearg) .type name,typearg;
/* In ELF C symbols are asm symbols. */
#undef NO_UNDERSCORES
#define NO_UNDERSCORES
#else
#define ALIGNARG(log2) log2
#define ASM_TYPE_DIRECTIVE(name,type) /* Nothing is specified. */
#endif
/* Define an entry point visible from C. */
#define ENTRY(name) \
ASM_GLOBAL_DIRECTIVE C_SYMBOL_NAME(name); \
ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),@function) \
.align ALIGNARG(4); \
C_LABEL(name) \
CALL_MCOUNT
/* If compiled for profiling, call `mcount' at the start of each function. */
#ifdef PROF
/* The mcount code relies on a normal frame pointer being on the stack
to locate our caller, so push one just for its benefit. */
#define CALL_MCOUNT \
pushl %ebp; movl %esp, %ebp; call JUMPTARGET(mcount); popl %ebp;
#else
#define CALL_MCOUNT /* Do nothing. */
#endif
#ifdef NO_UNDERSCORES
/* Since C identifiers are not normally prefixed with an underscore
on this system, the asm identifier `syscall_error' intrudes on the
C name space. Make sure we use an innocuous name. */
#define syscall_error __syscall_error
#define mcount _mcount
#endif
#define PSEUDO(name, syscall_name, args) \
lose: SYSCALL_PIC_SETUP \
jmp JUMPTARGET(syscall_error) \
.globl syscall_error; \
ENTRY (name) \
DO_CALL (syscall_name, args); \
jb lose
#ifdef PIC
#define JUMPTARGET(name) name##@PLT
#define SYSCALL_PIC_SETUP \
pushl %ebx; \
call 0f; \
0: popl %ebx; \
addl $_GLOBAL_OFFSET_TABLE+[.-0b], %ebx;
#else
#define JUMPTARGET(name) name
#define SYSCALL_PIC_SETUP /* Nothing. */
#endif
/* This is defined as a separate macro so that other sysdep.h files
can include this one and then redefine DO_CALL. */
#define DO_CALL(syscall_name, args) \
lea SYS_ify (syscall_name), %eax; \
/* lcall $7, $0; */ \
/* Above loses; GAS bug. */ \
.byte 0x9a, 0, 0, 0, 0, 7, 0
#define r0 %eax /* Normal return-value register. */
#define r1 %edx /* Secondary return-value register. */
#define scratch %ecx /* Call-clobbered register for random use. */
#define MOVE(x,y) movl x, y
#endif /* ASSEMBLER */
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