xref: /netbsd-src/lib/libpthread/arch/x86_64/pthread_md.h (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: pthread_md.h,v 1.7 2007/11/13 17:20:10 ad Exp $	*/
2 
3 /*-
4  * Copyright (c) 2001 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Nathan J. Williams.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  *
38  * Adapted for x86_64 by fvdl@NetBSD.org
39  */
40 
41 #ifndef _LIB_PTHREAD_X86_64_MD_H
42 #define _LIB_PTHREAD_X86_64_MD_H
43 
44 #include <sys/ucontext.h>
45 
46 static inline long
47 pthread__sp(void)
48 {
49 	long ret;
50 	__asm("movq %%rsp, %0" : "=g" (ret));
51 
52 	return ret;
53 }
54 
55 #define pthread__uc_sp(ucp) ((ucp)->uc_mcontext.__gregs[_REG_URSP])
56 #define pthread__uc_pc(ucp) ((ucp)->uc_mcontext.__gregs[_REG_RIP])
57 
58 /*
59  * Set initial, sane values for registers whose values aren't just
60  * "don't care".
61  * 0x23 is GSEL(GUDATA_SEL, SEL_UPL), and
62  * 0x1b is GSEL(GUCODE_SEL, SEL_UPL).
63  * 0x202 is PSL_USERSET.
64  */
65 #define _INITCONTEXT_U_MD(ucp)						\
66 	(ucp)->uc_mcontext.__gregs[_REG_GS] = 0x23,			\
67 	(ucp)->uc_mcontext.__gregs[_REG_FS] = 0x23,			\
68 	(ucp)->uc_mcontext.__gregs[_REG_ES] = 0x23,			\
69 	(ucp)->uc_mcontext.__gregs[_REG_DS] = 0x23,			\
70 	(ucp)->uc_mcontext.__gregs[_REG_CS] = 0x1b,			\
71 	(ucp)->uc_mcontext.__gregs[_REG_SS] = 0x23,			\
72 	(ucp)->uc_mcontext.__gregs[_REG_RFL] = 0x202;
73 
74 /*
75  * Usable stack space below the ucontext_t.
76  * See comment in pthread_switch.S about STACK_SWITCH.
77  */
78 #define STACKSPACE	64	/* room for 8 long values */
79 
80 /*
81  * Conversions between struct reg and struct mcontext. Used by
82  * libpthread_dbg.
83  */
84 
85 #define PTHREAD_UCONTEXT_TO_REG(reg, uc) \
86 	memcpy(reg, (uc)->uc_mcontext.__gregs, _NGREG * sizeof (long));
87 
88 #define PTHREAD_REG_TO_UCONTEXT(uc, reg) do {				\
89 	memcpy((uc)->uc_mcontext.__gregs, reg, _NGREG * sizeof (long)); \
90 	(uc)->uc_flags = ((uc)->uc_flags | _UC_CPU) & ~_UC_USER; 	\
91 	} while (/*CONSTCOND*/0)
92 
93 
94 #define PTHREAD_UCONTEXT_TO_FPREG(freg, uc)		       		\
95 	(void)memcpy(&(freg)->fxstate,					\
96         (uc)->uc_mcontext.__fpregs, sizeof(struct fpreg))
97 
98 #define PTHREAD_FPREG_TO_UCONTEXT(uc, freg) do {       	       		\
99 	(void)memcpy(							\
100         (uc)->uc_mcontext.__fpregs,					\
101 	&(freg)->fxstate, sizeof(struct fpreg));			\
102 	/*LINTED precision loss */					\
103 	(uc)->uc_flags = ((uc)->uc_flags | _UC_FPU) & ~_UC_USER;	\
104 	} while (/*CONSTCOND*/0)
105 
106 #define	pthread__smt_pause()	__asm __volatile("rep; nop" ::: "memory")
107 #define	PTHREAD__HAVE_ATOMIC
108 
109 static inline void *
110 pthread__atomic_cas_ptr(volatile void *ptr, const void *old, const void *new)
111 {
112 	volatile uintptr_t *cast = ptr;
113 	void *ret;
114 
115 	__asm __volatile ("lock; cmpxchgq %2, %1"
116 		: "=a" (ret), "=m" (*cast)
117 		: "r" (new), "m" (*cast), "0" (old));
118 
119 	return ret;
120 }
121 
122 static inline void *
123 pthread__atomic_cas_ptr_ni(volatile void *ptr, const void *old, const void *new)
124 {
125 	volatile uintptr_t *cast = ptr;
126 	void *ret;
127 
128 	__asm __volatile ("cmpxchgq %2, %1"
129 		: "=a" (ret), "=m" (*cast)
130 		: "r" (new), "m" (*cast), "0" (old));
131 
132 	return ret;
133 }
134 
135 #endif /* _LIB_PTHREAD_X86_64_MD_H */
136