uclibc-ng/libc/sysdeps/linux/mips/swapcontext.S

/* Save and set current context.
   Copyright (C) 2009 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Maciej W. Rozycki <macro@codesourcery.com>.

   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.

   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, see
   <http://www.gnu.org/licenses/>.  */

#include <sysdep.h>
#include <sys/asm.h>
#include <sys/fpregdef.h>
#include <sys/regdef.h>

#include "ucontext_i.h"

/* int swapcontext (ucontext_t *oucp, const ucontext_t *ucp) */

	.text
LOCALSZ = 0
ARGSZ = 0
MASK = 0x00000000
#ifdef __PIC__
LOCALSZ = 1						/* save gp */
#endif
#if _MIPS_SIM != _ABIO32
ARGSZ = 1						/* save a1 */
# ifdef __PIC__
MASK = 0x10000000
# endif
#endif
FRAMESZ = (((ARGSZ + LOCALSZ) * SZREG) + ALSZ) & ALMASK
GPOFF = FRAMESZ - ((ARGSZ + 1) * SZREG)
#if _MIPS_SIM != _ABIO32
A1OFF = FRAMESZ - (1 * SZREG)				/* callee-allocated */
#else
A1OFF = FRAMESZ + (1 * SZREG)				/* caller-allocated */
#endif

NESTED (__swapcontext, FRAMESZ, ra)
	.mask	MASK, -(ARGSZ * SZREG)
	.fmask	0x00000000, 0

#ifdef __PIC__
	SETUP_GP

	move	a2, sp
# define _SP a2

# if _MIPS_SIM != _ABIO32
	move	a3, gp
#  define _GP a3
# endif

	PTR_ADDIU sp, -FRAMESZ
	SETUP_GP64 (GPOFF, __swapcontext)
	SAVE_GP (GPOFF)

#else  /* ! __PIC__ */
# define _SP sp
# define _GP gp

#endif /* ! __PIC__ */

#ifdef PROF
	.set	noat
	move	AT, ra
	jal	_mcount
	.set	at
#endif

	/* Store a magic flag.	*/
	li	v1, 1
	REG_S	v1, (0 * SZREG + MCONTEXT_GREGS)(a0)	/* zero */

	REG_S	s0, (16 * SZREG + MCONTEXT_GREGS)(a0)
	REG_S	s1, (17 * SZREG + MCONTEXT_GREGS)(a0)
	REG_S	s2, (18 * SZREG + MCONTEXT_GREGS)(a0)
	REG_S	s3, (19 * SZREG + MCONTEXT_GREGS)(a0)
	REG_S	s4, (20 * SZREG + MCONTEXT_GREGS)(a0)
	REG_S	s5, (21 * SZREG + MCONTEXT_GREGS)(a0)
	REG_S	s6, (22 * SZREG + MCONTEXT_GREGS)(a0)
	REG_S	s7, (23 * SZREG + MCONTEXT_GREGS)(a0)
#if ! defined (__PIC__) || _MIPS_SIM != _ABIO32
	REG_S	_GP, (28 * SZREG + MCONTEXT_GREGS)(a0)
#endif
	REG_S	_SP, (29 * SZREG + MCONTEXT_GREGS)(a0)
	REG_S	fp, (30 * SZREG + MCONTEXT_GREGS)(a0)
	REG_S	ra, (31 * SZREG + MCONTEXT_GREGS)(a0)
	REG_S	ra, MCONTEXT_PC(a0)

#ifdef __mips_hard_float
# if _MIPS_SIM == _ABI64
	s.d	fs0, (24 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs1, (25 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs2, (26 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs3, (27 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs4, (28 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs5, (29 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs6, (30 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs7, (31 * SZREG + MCONTEXT_FPREGS)(a0)

# else  /* _MIPS_SIM != _ABI64 */
	s.d	fs0, (20 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs1, (22 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs2, (24 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs3, (26 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs4, (28 * SZREG + MCONTEXT_FPREGS)(a0)
	s.d	fs5, (30 * SZREG + MCONTEXT_FPREGS)(a0)

# endif /* _MIPS_SIM != _ABI64 */

	cfc1	v1, fcr31
	sw	v1, MCONTEXT_FPC_CSR(a0)
#endif /* __mips_hard_float */

	REG_S	a1, A1OFF(sp)

/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, &oucp->uc_sigmask, _NSIG8) */
	li	a3, _NSIG8
	PTR_ADDU a2, a0, UCONTEXT_SIGMASK
	PTR_ADDU a1, a1, UCONTEXT_SIGMASK
	li	a0, SIG_SETMASK

	li	v0, SYS_ify (rt_sigprocmask)
	syscall
	bnez	a3, 99f

	REG_L	v0, A1OFF(sp)

#ifdef __mips_hard_float
# if _MIPS_SIM == _ABI64
	l.d	fs0, (24 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs1, (25 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs2, (26 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs3, (27 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs4, (28 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs5, (29 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs6, (30 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs7, (31 * SZREG + MCONTEXT_FPREGS)(v0)

# else  /* _MIPS_SIM != _ABI64 */
	l.d	fs0, (20 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs1, (22 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs2, (24 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs3, (26 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs4, (28 * SZREG + MCONTEXT_FPREGS)(v0)
	l.d	fs5, (30 * SZREG + MCONTEXT_FPREGS)(v0)

# endif /* _MIPS_SIM != _ABI64 */

	lw	v1, MCONTEXT_FPC_CSR(v0)
	ctc1	v1, fcr31
#endif /* __mips_hard_float */

	/* Note the contents of argument registers will be random
	   unless makecontext() has been called.  */
	REG_L	a0, (4 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	a1, (5 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	a2, (6 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	a3, (7 * SZREG + MCONTEXT_GREGS)(v0)
#if _MIPS_SIM != _ABIO32
	REG_L	a4, (8 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	a5, (9 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	a6, (10 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	a7, (11 * SZREG + MCONTEXT_GREGS)(v0)
#endif

	REG_L	s0, (16 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	s1, (17 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	s2, (18 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	s3, (19 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	s4, (20 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	s5, (21 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	s6, (22 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	s7, (23 * SZREG + MCONTEXT_GREGS)(v0)
#if ! defined (__PIC__) || _MIPS_SIM != _ABIO32
	REG_L	gp, (28 * SZREG + MCONTEXT_GREGS)(v0)
#endif
	REG_L	sp, (29 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	fp, (30 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	ra, (31 * SZREG + MCONTEXT_GREGS)(v0)
	REG_L	t9, MCONTEXT_PC(v0)

	move	v0, zero
	jr	t9

99:
#ifdef __PIC__
	PTR_LA	t9, JUMPTARGET (__syscall_error)
	RESTORE_GP64
	PTR_ADDIU sp, FRAMESZ
	jr	t9

#else  /* ! __PIC__ */

	j	JUMPTARGET (__syscall_error)
#endif /* ! __PIC__ */
PSEUDO_END (__swapcontext)

weak_alias (__swapcontext, swapcontext)