1 /*
  2  * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
  3  * Copyright (c) 2012, 2016 SAP SE. All rights reserved.
  4  * Copyright (c) 2020, 2021, Huawei Technologies Co., Ltd. All rights reserved.
  5  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  6  *
  7  * This code is free software; you can redistribute it and/or modify it
  8  * under the terms of the GNU General Public License version 2 only, as
  9  * published by the Free Software Foundation.
 10  *
 11  * This code is distributed in the hope that it will be useful, but WITHOUT
 12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 14  * version 2 for more details (a copy is included in the LICENSE file that
 15  * accompanied this code).
 16  *
 17  * You should have received a copy of the GNU General Public License version
 18  * 2 along with this work; if not, write to the Free Software Foundation,
 19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 20  *
 21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 22  * or visit www.oracle.com if you need additional information or have any
 23  * questions.
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 25  */
 26 
 27 #ifndef CPU_RISCV_BYTES_RISCV_HPP
 28 #define CPU_RISCV_BYTES_RISCV_HPP
 29 
 30 #include "memory/allocation.hpp"
 31 
 32 class Bytes: AllStatic {
 33  public:
 34   // Efficient reading and writing of unaligned unsigned data in platform-specific byte ordering
 35   // RISCV needs to check for alignment.
 36 
 37   // Forward declarations of the compiler-dependent implementation
 38   static inline u2 swap_u2(u2 x);
 39   static inline u4 swap_u4(u4 x);
 40   static inline u8 swap_u8(u8 x);
 41 
 42   static inline u2 get_native_u2(address p) {
 43     if ((intptr_t(p) & 1) == 0) {
 44       return *(u2*)p;
 45     } else {
 46       return ((u2)(p[1]) << 8) |
 47              ((u2)(p[0]));
 48     }
 49   }
 50 
 51   static inline u4 get_native_u4(address p) {
 52     switch (intptr_t(p) & 3) {
 53       case 0:
 54         return *(u4*)p;
 55 
 56       case 2:
 57         return ((u4)(((u2*)p)[1]) << 16) |
 58                ((u4)(((u2*)p)[0]));
 59 
 60       default:
 61         return ((u4)(p[3]) << 24) |
 62                ((u4)(p[2]) << 16) |
 63                ((u4)(p[1]) <<  8) |
 64                ((u4)(p[0]));
 65     }
 66   }
 67 
 68   static inline u8 get_native_u8(address p) {
 69     switch (intptr_t(p) & 7) {
 70       case 0:
 71         return *(u8*)p;
 72 
 73       case 4:
 74         return ((u8)(((u4*)p)[1]) << 32) |
 75                ((u8)(((u4*)p)[0]));
 76 
 77       case 2:
 78         return ((u8)(((u2*)p)[3]) << 48) |
 79                ((u8)(((u2*)p)[2]) << 32) |
 80                ((u8)(((u2*)p)[1]) << 16) |
 81                ((u8)(((u2*)p)[0]));
 82 
 83       default:
 84         return ((u8)(p[7]) << 56) |
 85                ((u8)(p[6]) << 48) |
 86                ((u8)(p[5]) << 40) |
 87                ((u8)(p[4]) << 32) |
 88                ((u8)(p[3]) << 24) |
 89                ((u8)(p[2]) << 16) |
 90                ((u8)(p[1]) <<  8) |
 91                ((u8)(p[0]));
 92     }
 93   }
 94 
 95   static inline void put_native_u2(address p, u2 x) {
 96     if ((intptr_t(p) & 1) == 0) {
 97       *(u2*)p = x;
 98     } else {
 99       p[1] = x >> 8;
100       p[0] = x;
101     }
102   }
103 
104   static inline void put_native_u4(address p, u4 x) {
105     switch (intptr_t(p) & 3) {
106       case 0:
107         *(u4*)p = x;
108         break;
109 
110       case 2:
111         ((u2*)p)[1] = x >> 16;
112         ((u2*)p)[0] = x;
113         break;
114 
115       default:
116         ((u1*)p)[3] = x >> 24;
117         ((u1*)p)[2] = x >> 16;
118         ((u1*)p)[1] = x >>  8;
119         ((u1*)p)[0] = x;
120         break;
121     }
122   }
123 
124   static inline void put_native_u8(address p, u8 x) {
125     switch (intptr_t(p) & 7) {
126       case 0:
127         *(u8*)p = x;
128         break;
129 
130       case 4:
131         ((u4*)p)[1] = x >> 32;
132         ((u4*)p)[0] = x;
133         break;
134 
135       case 2:
136         ((u2*)p)[3] = x >> 48;
137         ((u2*)p)[2] = x >> 32;
138         ((u2*)p)[1] = x >> 16;
139         ((u2*)p)[0] = x;
140         break;
141 
142       default:
143         ((u1*)p)[7] = x >> 56;
144         ((u1*)p)[6] = x >> 48;
145         ((u1*)p)[5] = x >> 40;
146         ((u1*)p)[4] = x >> 32;
147         ((u1*)p)[3] = x >> 24;
148         ((u1*)p)[2] = x >> 16;
149         ((u1*)p)[1] = x >>  8;
150         ((u1*)p)[0] = x;
151         break;
152     }
153   }
154 
155   // Efficient reading and writing of unaligned unsigned data in Java byte ordering (i.e. big-endian ordering)
156   static inline u2 get_Java_u2(address p) { return swap_u2(get_native_u2(p)); }
157   static inline u4 get_Java_u4(address p) { return swap_u4(get_native_u4(p)); }
158   static inline u8 get_Java_u8(address p) { return swap_u8(get_native_u8(p)); }
159 
160   static inline void put_Java_u2(address p, u2 x) { put_native_u2(p, swap_u2(x)); }
161   static inline void put_Java_u4(address p, u4 x) { put_native_u4(p, swap_u4(x)); }
162   static inline void put_Java_u8(address p, u8 x) { put_native_u8(p, swap_u8(x)); }
163 };
164 
165 #include OS_CPU_HEADER(bytes)
166 
167 #endif // CPU_RISCV_BYTES_RISCV_HPP