diff -r fd16c54261b3 -r 489c9b5090e2 hotspot/src/cpu/x86/vm/bytes_x86.hpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/hotspot/src/cpu/x86/vm/bytes_x86.hpp Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,70 @@ +/* + * Copyright 1997-2001 Sun Microsystems, Inc. All Rights Reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + */ + +class Bytes: AllStatic { + private: +#ifndef AMD64 + // Helper function for swap_u8 + static inline u8 swap_u8_base(u4 x, u4 y); // compiler-dependent implementation +#endif // AMD64 + + public: + // Returns true if the byte ordering used by Java is different from the native byte ordering + // of the underlying machine. For example, this is true for Intel x86, but false for Solaris + // on Sparc. + static inline bool is_Java_byte_ordering_different(){ return true; } + + + // Efficient reading and writing of unaligned unsigned data in platform-specific byte ordering + // (no special code is needed since x86 CPUs can access unaligned data) + static inline u2 get_native_u2(address p) { return *(u2*)p; } + static inline u4 get_native_u4(address p) { return *(u4*)p; } + static inline u8 get_native_u8(address p) { return *(u8*)p; } + + static inline void put_native_u2(address p, u2 x) { *(u2*)p = x; } + static inline void put_native_u4(address p, u4 x) { *(u4*)p = x; } + static inline void put_native_u8(address p, u8 x) { *(u8*)p = x; } + + + // Efficient reading and writing of unaligned unsigned data in Java + // byte ordering (i.e. big-endian ordering). Byte-order reversal is + // needed since x86 CPUs use little-endian format. + static inline u2 get_Java_u2(address p) { return swap_u2(get_native_u2(p)); } + static inline u4 get_Java_u4(address p) { return swap_u4(get_native_u4(p)); } + static inline u8 get_Java_u8(address p) { return swap_u8(get_native_u8(p)); } + + static inline void put_Java_u2(address p, u2 x) { put_native_u2(p, swap_u2(x)); } + static inline void put_Java_u4(address p, u4 x) { put_native_u4(p, swap_u4(x)); } + static inline void put_Java_u8(address p, u8 x) { put_native_u8(p, swap_u8(x)); } + + + // Efficient swapping of byte ordering + static inline u2 swap_u2(u2 x); // compiler-dependent implementation + static inline u4 swap_u4(u4 x); // compiler-dependent implementation + static inline u8 swap_u8(u8 x); +}; + + +// The following header contains the implementations of swap_u2, swap_u4, and swap_u8[_base] +#include "incls/_bytes_pd.inline.hpp.incl"