1 /* Copyright (C) 2005 Free Software Foundation, Inc. 2 Contributed by Richard Henderson <rth@redhat.com>. 3 4 This file is part of the GNU OpenMP Library (libgomp). 5 6 Libgomp is free software; you can redistribute it and/or modify it 7 under the terms of the GNU Lesser General Public License as published by 8 the Free Software Foundation; either version 2.1 of the License, or 9 (at your option) any later version. 10 11 Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY 12 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 13 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for 14 more details. 15 16 You should have received a copy of the GNU Lesser General Public License 17 along with libgomp; see the file COPYING.LIB. If not, write to the 18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, 19 MA 02110-1301, USA. */ 20 21 /* As a special exception, if you link this library with other files, some 22 of which are compiled with GCC, to produce an executable, this library 23 does not by itself cause the resulting executable to be covered by the 24 GNU General Public License. This exception does not however invalidate 25 any other reasons why the executable file might be covered by the GNU 26 General Public License. */ 27 28 /* Provide target-specific access to the futex system call. */ 29 30 #define FUTEX_WAIT 0 31 #define FUTEX_WAKE 1 32 33 #ifdef __LP64__ 34 # ifndef SYS_futex 35 # define SYS_futex 202 36 # endif 37 38 static inline void 39 futex_wait (int *addr, int val) 40 { 41 register long r10 __asm__("%r10") = 0; 42 long res; 43 44 __asm volatile ("syscall" 45 : "=a" (res) 46 : "0"(SYS_futex), "D" (addr), "S"(FUTEX_WAIT), 47 "d"(val), "r"(r10) 48 : "r11", "rcx", "memory"); 49 } 50 51 static inline void 52 futex_wake (int *addr, int count) 53 { 54 long res; 55 56 __asm volatile ("syscall" 57 : "=a" (res) 58 : "0"(SYS_futex), "D" (addr), "S"(FUTEX_WAKE), "d"(count) 59 : "r11", "rcx", "memory"); 60 } 61 #else 62 # ifndef SYS_futex 63 # define SYS_futex 240 64 # endif 65 66 # ifdef __PIC__ 67 68 static inline void 69 sys_futex0 (int *addr, int op, int val) 70 { 71 long res; 72 73 __asm volatile ("xchgl\t%%ebx, %2\n\t" 74 "int\t$0x80\n\t" 75 "xchgl\t%%ebx, %2" 76 : "=a" (res) 77 : "0"(SYS_futex), "r" (addr), "c"(op), 78 "d"(val), "S"(0) 79 : "memory"); 80 } 81 82 # else 83 84 static inline void 85 sys_futex0 (int *addr, int op, int val) 86 { 87 long res; 88 89 __asm volatile ("int $0x80" 90 : "=a" (res) 91 : "0"(SYS_futex), "b" (addr), "c"(op), 92 "d"(val), "S"(0) 93 : "memory"); 94 } 95 96 # endif /* __PIC__ */ 97 98 static inline void 99 futex_wait (int *addr, int val) 100 { 101 sys_futex0 (addr, FUTEX_WAIT, val); 102 } 103 104 static inline void 105 futex_wake (int *addr, int count) 106 { 107 sys_futex0 (addr, FUTEX_WAKE, count); 108 } 109 110 #endif /* __LP64__ */ 111