never@1445: /*
stefank@2314:  * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
never@1445:  * Copyright 2007, 2008, 2009 Red Hat, Inc.
never@1445:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
never@1445:  *
never@1445:  * This code is free software; you can redistribute it and/or modify it
never@1445:  * under the terms of the GNU General Public License version 2 only, as
never@1445:  * published by the Free Software Foundation.
never@1445:  *
never@1445:  * This code is distributed in the hope that it will be useful, but WITHOUT
never@1445:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
never@1445:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
never@1445:  * version 2 for more details (a copy is included in the LICENSE file that
never@1445:  * accompanied this code).
never@1445:  *
never@1445:  * You should have received a copy of the GNU General Public License version
never@1445:  * 2 along with this work; if not, write to the Free Software Foundation,
never@1445:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
never@1445:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
never@1445:  *
never@1445:  */
never@1445: 
stefank@2314: #ifndef CPU_ZERO_VM_BYTES_ZERO_HPP
stefank@2314: #define CPU_ZERO_VM_BYTES_ZERO_HPP
stefank@2314: 
stefank@2314: #include "memory/allocation.hpp"
stefank@2314: 
never@1445: typedef union unaligned {
never@1445:   u4 u;
never@1445:   u2 us;
never@1445:   u8 ul;
never@1445: } __attribute__((packed)) unaligned;
never@1445: 
never@1445: class Bytes: AllStatic {
never@1445:  public:
never@1445:   // Returns true if the byte ordering used by Java is different
never@1445:   // from the native byte ordering of the underlying machine.
never@1445:   static inline bool is_Java_byte_ordering_different() {
never@1445: #ifdef VM_LITTLE_ENDIAN
never@1445:     return true;
never@1445: #else
never@1445:     return false;
never@1445: #endif
never@1445:   }
never@1445: 
never@1445:   // Efficient reading and writing of unaligned unsigned data in
never@1445:   // platform-specific byte ordering.
never@1445:   static inline u2 get_native_u2(address p){
never@1445:     unaligned *up = (unaligned *) p;
never@1445:     return up->us;
never@1445:   }
never@1445: 
never@1445:   static inline u4 get_native_u4(address p) {
never@1445:     unaligned *up = (unaligned *) p;
never@1445:     return up->u;
never@1445:   }
never@1445: 
never@1445:   static inline u8 get_native_u8(address p) {
never@1445:     unaligned *up = (unaligned *) p;
never@1445:     return up->ul;
never@1445:   }
never@1445: 
never@1445:   static inline void put_native_u2(address p, u2 x) {
never@1445:     unaligned *up = (unaligned *) p;
never@1445:     up->us = x;
never@1445:   }
never@1445: 
never@1445:   static inline void put_native_u4(address p, u4 x) {
never@1445:     unaligned *up = (unaligned *) p;
never@1445:     up->u = x;
never@1445:   }
never@1445: 
never@1445:   static inline void put_native_u8(address p, u8 x) {
never@1445:     unaligned *up = (unaligned *) p;
never@1445:     up->ul = x;
never@1445:   }
never@1445: 
never@1445:   // Efficient reading and writing of unaligned unsigned data in Java
never@1445:   // byte ordering (i.e. big-endian ordering).
never@1445: #ifdef VM_LITTLE_ENDIAN
never@1445:   // Byte-order reversal is needed
never@1445:   static inline u2 get_Java_u2(address p) {
never@1445:     return (u2(p[0]) << 8) |
never@1445:            (u2(p[1])     );
never@1445:   }
never@1445:   static inline u4 get_Java_u4(address p) {
never@1445:     return (u4(p[0]) << 24) |
never@1445:            (u4(p[1]) << 16) |
never@1445:            (u4(p[2]) <<  8) |
never@1445:            (u4(p[3])      );
never@1445:   }
never@1445:   static inline u8 get_Java_u8(address p) {
never@1445:     u4 hi, lo;
never@1445:     hi = (u4(p[0]) << 24) |
never@1445:          (u4(p[1]) << 16) |
never@1445:          (u4(p[2]) <<  8) |
never@1445:          (u4(p[3])      );
never@1445:     lo = (u4(p[4]) << 24) |
never@1445:          (u4(p[5]) << 16) |
never@1445:          (u4(p[6]) <<  8) |
never@1445:          (u4(p[7])      );
never@1445:     return u8(lo) | (u8(hi) << 32);
never@1445:   }
never@1445: 
never@1445:   static inline void put_Java_u2(address p, u2 x) {
never@1445:     p[0] = x >> 8;
never@1445:     p[1] = x;
never@1445:   }
never@1445:   static inline void put_Java_u4(address p, u4 x) {
never@1445:     p[0] = x >> 24;
never@1445:     p[1] = x >> 16;
never@1445:     p[2] = x >> 8;
never@1445:     p[3] = x;
never@1445:   }
never@1445:   static inline void put_Java_u8(address p, u8 x) {
never@1445:     u4 hi, lo;
never@1445:     lo = x;
never@1445:     hi = x >> 32;
never@1445:     p[0] = hi >> 24;
never@1445:     p[1] = hi >> 16;
never@1445:     p[2] = hi >> 8;
never@1445:     p[3] = hi;
never@1445:     p[4] = lo >> 24;
never@1445:     p[5] = lo >> 16;
never@1445:     p[6] = lo >> 8;
never@1445:     p[7] = lo;
never@1445:   }
never@1445: 
never@1445:   // Efficient swapping of byte ordering
never@1445:   static inline u2 swap_u2(u2 x);
never@1445:   static inline u4 swap_u4(u4 x);
never@1445:   static inline u8 swap_u8(u8 x);
never@1445: #else
never@1445:   // No byte-order reversal is needed
never@1445:   static inline u2 get_Java_u2(address p) {
never@1445:     return get_native_u2(p);
never@1445:   }
never@1445:   static inline u4 get_Java_u4(address p) {
never@1445:     return get_native_u4(p);
never@1445:   }
never@1445:   static inline u8 get_Java_u8(address p) {
never@1445:     return get_native_u8(p);
never@1445:   }
never@1445: 
never@1445:   static inline void put_Java_u2(address p, u2 x) {
never@1445:     put_native_u2(p, x);
never@1445:   }
never@1445:   static inline void put_Java_u4(address p, u4 x) {
never@1445:     put_native_u4(p, x);
never@1445:   }
never@1445:   static inline void put_Java_u8(address p, u8 x) {
never@1445:     put_native_u8(p, x);
never@1445:   }
never@1445: 
never@1445:   // No byte-order reversal is needed
never@1445:   static inline u2 swap_u2(u2 x) { return x; }
never@1445:   static inline u4 swap_u4(u4 x) { return x; }
never@1445:   static inline u8 swap_u8(u8 x) { return x; }
never@1445: #endif // VM_LITTLE_ENDIAN
never@1445: };
never@1445: 
never@1445: #ifdef VM_LITTLE_ENDIAN
never@1445: // The following header contains the implementations of swap_u2,
never@1445: // swap_u4, and swap_u8
stefank@2314: #ifdef TARGET_OS_ARCH_linux_zero
stefank@2314: # include "bytes_linux_zero.inline.hpp"
stefank@2314: #endif
never@3156: #ifdef TARGET_OS_ARCH_bsd_zero
never@3156: # include "bytes_bsd_zero.inline.hpp"
never@3156: #endif
stefank@2314: 
never@1445: #endif // VM_LITTLE_ENDIAN
stefank@2314: 
stefank@2314: #endif // CPU_ZERO_VM_BYTES_ZERO_HPP