lib/libc/arch/sparc/SYS.h
/*-
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This software was developed by the Computer Systems Engineering group
 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
 * contributed to Berkeley.
 *
 * 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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 *	@(#)SYS.h	8.1 (Berkeley) 6/4/93
 *
 *	from: Header: SYS.h,v 1.2 92/07/03 18:57:00 torek Exp
 *	$NetBSD: SYS.h,v 1.18 2011/03/28 11:19:12 martin Exp $
 */

#include <machine/asm.h>
#include <sys/syscall.h>
#include <machine/trap.h>

#ifdef __STDC__
#define _CAT(x,y) x##y
#else
#define _CAT(x,y) x/**/y
#endif

#ifdef __ELF__
#define CERROR		_C_LABEL(__cerror)
#define CURBRK		_C_LABEL(__curbrk)
#else
#define CERROR		_ASM_LABEL(cerror)
#define CURBRK		_ASM_LABEL(curbrk)
#endif

/*
 * ERROR branches to cerror.
 */
#ifdef PIC
#define CALL(name)				\
	PIC_PROLOGUE(%g1, %g5);			\
	set	name, %g5;			\
	ld	[%g1 + %g5], %g5;		\
	jmp	%g5;				\
	 nop
#else
#define	CALL(name)				\
	set	name, %g1;			\
	jmp	%g1;				\
	 nop
#endif
#define	ERROR() CALL(CERROR)

/*
 * SYSCALL is used when further action must be taken before returning.
 * Note that it adds a `nop' over what we could do, if we only knew
 * what came at label 1....
 */
#define	_SYSCALL(x,y)				\
ENTRY(x);					\
	mov	_CAT(SYS_,y), %g1;		\
	t	ST_SYSCALL;			\
	bcc	1f;				\
	 nop;					\
	ERROR();				\
1:	/* next insn */

#define	SYSCALL(x)				\
	_SYSCALL(x,x)

/*
 * RSYSCALL is used when the system call should just return.  Here we
 * use the SYSCALL_G5RFLAG to put the `success' return address in %g5
 * and avoid a branch.
 *
 * PSEUDO(x,y) is like RSYSCALL(y), except that the name is x.
 */
#define	_RSYSCALL(x,y)					\
ENTRY(x);						\
	mov	(_CAT(SYS_,y)) | SYSCALL_G5RFLAG, %g1;	\
	add	%o7, 8, %g5;				\
	t	ST_SYSCALL;				\
	ERROR()

#define	RSYSCALL(x)	_RSYSCALL(x,x)
#define	PSEUDO(x,y)	_RSYSCALL(x,y)

/*
 * WSYSCALL(weak,strong) is like RSYSCALL(weak),
 * except that weak is a weak internal alias for the strong symbol.
 */
#ifdef WEAK_ALIAS
#define	WSYSCALL(weak,strong)			\
	WEAK_ALIAS(weak,strong);		\
	PSEUDO(strong,weak)
#else
#define	WSYSCALL(weak,strong)			\
	RSYSCALL(weak)
#endif

/*
 * SYSCALL_NOERROR is like SYSCALL, except it's used for syscalls that
 * never fail.
 *
 * XXX - This should be optimized.
 */
#define SYSCALL_NOERROR(x)			\
ENTRY(x);					\
	mov	_CAT(SYS_,x), %g1;		\
	t	ST_SYSCALL

/*
 * RSYSCALL_NOERROR is like RSYSCALL, except it's used for syscalls
 * that never fail.
 *
 * PSEUDO_NOERROR(x,y) is like RSYSCALL_NOERROR(y), except that the
 * name is x.
 *
 * XXX - This should be optimized.
 */
#define _RSYSCALL_NOERROR(x,y)				\
ENTRY(x);						\
	mov	(_CAT(SYS_,y)) | SYSCALL_G5RFLAG, %g1;	\
	add	%o7, 8, %g5;				\
	t	ST_SYSCALL

#define RSYSCALL_NOERROR(x)	_RSYSCALL_NOERROR(x,x)
#define PSEUDO_NOERROR(x,y)	_RSYSCALL_NOERROR(x,y)

	.globl	CERROR
