NetBSD/lib/libpthread/arch/i386/pthread_md.h

109 lines
3.5 KiB
C

/* $NetBSD: pthread_md.h,v 1.19 2011/02/24 04:28:43 joerg Exp $ */
/*-
* Copyright (c) 2001, 2007, 2008 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Nathan J. Williams, and by Andrew Doran.
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#ifndef _LIB_PTHREAD_I386_MD_H
#define _LIB_PTHREAD_I386_MD_H
#include <sys/ucontext.h>
#include <ucontext.h>
static inline unsigned long
pthread__sp(void)
{
unsigned long ret;
__asm("movl %%esp, %0" : "=g" (ret));
return ret;
}
#define pthread__uc_sp(ucp) ((ucp)->uc_mcontext.__gregs[_REG_UESP])
/*
* Set initial, sane values for registers whose values aren't just
* "don't care".
*
* We use the current context instead of a guessed one because we cannot
* assume how the GDT entries are ordered: what is true on i386 is not
* true anymore on amd64.
*/
#define _INITCONTEXT_U_MD(ucp) \
do { \
ucontext_t ucur; \
(void)getcontext(&ucur); \
(ucp)->uc_mcontext.__gregs[_REG_GS] = \
ucur.uc_mcontext.__gregs[_REG_GS], \
(ucp)->uc_mcontext.__gregs[_REG_FS] = \
ucur.uc_mcontext.__gregs[_REG_FS], \
(ucp)->uc_mcontext.__gregs[_REG_ES] = \
ucur.uc_mcontext.__gregs[_REG_ES], \
(ucp)->uc_mcontext.__gregs[_REG_DS] = \
ucur.uc_mcontext.__gregs[_REG_DS], \
(ucp)->uc_mcontext.__gregs[_REG_CS] = \
ucur.uc_mcontext.__gregs[_REG_CS], \
(ucp)->uc_mcontext.__gregs[_REG_SS] = \
ucur.uc_mcontext.__gregs[_REG_SS], \
(ucp)->uc_mcontext.__gregs[_REG_EFL] = \
ucur.uc_mcontext.__gregs[_REG_EFL]; \
} while (/*CONSTCOND*/0);
#define pthread__smt_pause() __asm __volatile("rep; nop" ::: "memory")
/* Don't need additional memory barriers. */
#define PTHREAD__ATOMIC_IS_MEMBAR
static inline void *
_atomic_cas_ptr(volatile void *ptr, void *old, void *new)
{
volatile uintptr_t *cast = ptr;
void *ret;
__asm __volatile ("lock; cmpxchgl %2, %1"
: "=a" (ret), "=m" (*cast)
: "r" (new), "m" (*cast), "0" (old));
return ret;
}
static inline void *
_atomic_cas_ptr_ni(volatile void *ptr, void *old, void *new)
{
volatile uintptr_t *cast = ptr;
void *ret;
__asm __volatile ("cmpxchgl %2, %1"
: "=a" (ret), "=m" (*cast)
: "r" (new), "m" (*cast), "0" (old));
return ret;
}
#endif /* _LIB_PTHREAD_I386_MD_H */