os_linux_zero.hpp revision 13147:5eaba310927e
1/* 2 * Copyright (c) 2003, 2017, Oracle and/or its affiliates. All rights reserved. 3 * Copyright 2007, 2008, 2010 Red Hat, Inc. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 * 24 */ 25 26#ifndef OS_CPU_LINUX_ZERO_VM_OS_LINUX_ZERO_HPP 27#define OS_CPU_LINUX_ZERO_VM_OS_LINUX_ZERO_HPP 28 29 static void setup_fpu() {} 30 31 static bool is_allocatable(size_t bytes); 32 33 // Used to register dynamic code cache area with the OS 34 // Note: Currently only used in 64 bit Windows implementations 35 static bool register_code_area(char *low, char *high) { return true; } 36 37 // Atomically copy 64 bits of data 38 static void atomic_copy64(const volatile void *src, volatile void *dst) { 39#if defined(PPC32) 40 double tmp; 41 asm volatile ("lfd %0, 0(%1)\n" 42 "stfd %0, 0(%2)\n" 43 : "=f"(tmp) 44 : "b"(src), "b"(dst)); 45#elif defined(S390) && !defined(_LP64) 46 double tmp; 47 asm volatile ("ld %0, 0(%1)\n" 48 "std %0, 0(%2)\n" 49 : "=r"(tmp) 50 : "a"(src), "a"(dst)); 51#else 52 *(jlong *) dst = *(const jlong *) src; 53#endif 54 } 55 56#endif // OS_CPU_LINUX_ZERO_VM_OS_LINUX_ZERO_HPP 57