1 /*
2 * Copyright (c) 1997, 2002, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 class Bytes: AllStatic {
26 public:
27 // Efficient reading and writing of unaligned unsigned data in platform-specific byte ordering
28 // Sparc needs to check for alignment.
29
30 // can I count on address always being a pointer to an unsigned char? Yes
31
32 // Returns true, if the byte ordering used by Java is different from the nativ byte ordering
33 // of the underlying machine. For example, true for Intel x86, False, for Solaris on Sparc.
34 static inline bool is_Java_byte_ordering_different() { return false; }
35
36 // Thus, a swap between native and Java ordering is always a no-op:
37 static inline u2 swap_u2(u2 x) { return x; }
38 static inline u4 swap_u4(u4 x) { return x; }
39 static inline u8 swap_u8(u8 x) { return x; }
40
41 static inline u2 get_native_u2(address p){
42 return (intptr_t(p) & 1) == 0
43 ? *(u2*)p
44 : ( u2(p[0]) << 8 )
45 | ( u2(p[1]) );
46 }
47
48 static inline u4 get_native_u4(address p) {
49 switch (intptr_t(p) & 3) {
50 case 0: return *(u4*)p;
51
52 case 2: return ( u4( ((u2*)p)[0] ) << 16 )
53 | ( u4( ((u2*)p)[1] ) );
54
55 default: return ( u4(p[0]) << 24 )
56 | ( u4(p[1]) << 16 )
57 | ( u4(p[2]) << 8 )
58 | u4(p[3]);
59 }
60 }
61
62 static inline u8 get_native_u8(address p) {
63 switch (intptr_t(p) & 7) {
64 case 0: return *(u8*)p;
65
66 case 4: return ( u8( ((u4*)p)[0] ) << 32 )
67 | ( u8( ((u4*)p)[1] ) );
68
69 case 2: return ( u8( ((u2*)p)[0] ) << 48 )
70 | ( u8( ((u2*)p)[1] ) << 32 )
71 | ( u8( ((u2*)p)[2] ) << 16 )
72 | ( u8( ((u2*)p)[3] ) );
73
74 default: return ( u8(p[0]) << 56 )
75 | ( u8(p[1]) << 48 )
76 | ( u8(p[2]) << 40 )
77 | ( u8(p[3]) << 32 )
78 | ( u8(p[4]) << 24 )
79 | ( u8(p[5]) << 16 )
80 | ( u8(p[6]) << 8 )
81 | u8(p[7]);
82 }
83 }
84
85
86
87 static inline void put_native_u2(address p, u2 x) {
88 if ( (intptr_t(p) & 1) == 0 ) *(u2*)p = x;
89 else {
90 p[0] = x >> 8;
91 p[1] = x;
92 }
93 }
94
95 static inline void put_native_u4(address p, u4 x) {
96 switch ( intptr_t(p) & 3 ) {
97 case 0: *(u4*)p = x;
98 break;
99
100 case 2: ((u2*)p)[0] = x >> 16;
101 ((u2*)p)[1] = x;
102 break;
103
104 default: ((u1*)p)[0] = x >> 24;
105 ((u1*)p)[1] = x >> 16;
106 ((u1*)p)[2] = x >> 8;
107 ((u1*)p)[3] = x;
108 break;
109 }
110 }
111
112 static inline void put_native_u8(address p, u8 x) {
113 switch ( intptr_t(p) & 7 ) {
114 case 0: *(u8*)p = x;
115 break;
116
117 case 4: ((u4*)p)[0] = x >> 32;
118 ((u4*)p)[1] = x;
119 break;
120
121 case 2: ((u2*)p)[0] = x >> 48;
122 ((u2*)p)[1] = x >> 32;
123 ((u2*)p)[2] = x >> 16;
124 ((u2*)p)[3] = x;
125 break;
126
127 default: ((u1*)p)[0] = x >> 56;
128 ((u1*)p)[1] = x >> 48;
129 ((u1*)p)[2] = x >> 40;
130 ((u1*)p)[3] = x >> 32;
131 ((u1*)p)[4] = x >> 24;
132 ((u1*)p)[5] = x >> 16;
133 ((u1*)p)[6] = x >> 8;
134 ((u1*)p)[7] = x;
135 }
136 }
137
138
139 // Efficient reading and writing of unaligned unsigned data in Java byte ordering (i.e. big-endian ordering)
140 // (no byte-order reversal is needed since SPARC CPUs are big-endian oriented)
141 static inline u2 get_Java_u2(address p) { return get_native_u2(p); }
142 static inline u4 get_Java_u4(address p) { return get_native_u4(p); }
143 static inline u8 get_Java_u8(address p) { return get_native_u8(p); }
144
145 static inline void put_Java_u2(address p, u2 x) { put_native_u2(p, x); }
146 static inline void put_Java_u4(address p, u4 x) { put_native_u4(p, x); }
147 static inline void put_Java_u8(address p, u8 x) { put_native_u8(p, x); }
148 };
149
150 //Reconciliation History
151 // 1.7 98/02/24 10:18:41 bytes_i486.hpp
152 // 1.10 98/04/08 18:47:57 bytes_i486.hpp
153 // 1.13 98/07/15 17:10:03 bytes_i486.hpp
154 // 1.14 98/08/13 10:38:23 bytes_i486.hpp
155 // 1.15 98/10/05 16:30:21 bytes_i486.hpp
156 // 1.17 99/06/22 16:37:35 bytes_i486.hpp
157 //End