xref: /src/sys/arch/mips/include/regdef.h

/*	$NetBSD: regdef.h,v 1.14 2020/07/26 08:08:41 simonb Exp $	*/

/*
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Ralph Campbell. This file is derived from the MIPS RISC
 * Architecture book by Gerry Kane.
 *
 * 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.
 *
 *	@(#)regdef.h	8.1 (Berkeley) 6/10/93
 */

#ifndef _MIPS_REGDEF_H
#define	_MIPS_REGDEF_H

#include <machine/cdefs.h>	/* for API selection */

#define	zero	$0	/* always zero */
#define	AT	$at	/* assembler temporary */
#define	v0	$2	/* return value */
#define	v1	$3
#define	a0	$4	/* argument registers */
#define	a1	$5
#define	a2	$6
#define	a3	$7
#if defined(__mips_n32) || defined(__mips_n64)
#define	a4	$8
#define	a5	$9
#define	a6	$10
#define	a7	$11
#define	t0	$12	/* temp registers (not saved across subroutine calls) */
#define	t1	$13
#define	t2	$14
#define	t3	$15
#else
#define	t0	$8	/* temp registers (not saved across subroutine calls) */
#define	t1	$9
#define	t2	$10
#define	t3	$11
#define	t4	$12
#define	t5	$13
#define	t6	$14
#define	t7	$15
#endif /* __mips_n32 || __mips_n64 */
#define	s0	$16	/* saved across subroutine calls (callee saved) */
#define	s1	$17
#define	s2	$18
#define	s3	$19
#define	s4	$20
#define	s5	$21
#define	s6	$22
#define	s7	$23
#define	t8	$24	/* two more temporary registers */
#define	t9	$25
#define	k0	$26	/* kernel temporary */
#define	k1	$27
#define	gp	$28	/* global pointer */
#define	sp	$29	/* stack pointer */
#define	s8	$30	/* one more callee saved */
#define	ra	$31	/* return address */

/*
 * These are temp registers whose names can be used in either the old
 * or new ABI, although they map to different physical registers.  In
 * the old ABI, they map to t4-t7, and in the new ABI, they map to a4-a7.
 *
 * Because they overlap with the last 4 arg regs in the new ABI, ta0-ta3
 * should be used only when we need more than t0-t3.
 */
#if defined(__mips_n32) || defined(__mips_n64)
#define	ta0	$8
#define	ta1	$9
#define	ta2	$10
#define	ta3	$11
#else
#define	ta0	$12
#define	ta1	$13
#define	ta2	$14
#define	ta3	$15
#endif /* __mips_n32 || __mips_n64 */

#ifdef _KERNEL
#define	MIPS_CURLWP	t8	/* needs to synced with cpu.h */
#endif

#endif /* _MIPS_REGDEF_H */