1 /* 2 * Copyright (c) 2003, 2008, 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 // Assembly code for platforms that need it. 26 extern "C" { 27 void _Copy_conjoint_words(HeapWord* from, HeapWord* to, size_t count); 28 void _Copy_disjoint_words(HeapWord* from, HeapWord* to, size_t count); 29 30 void _Copy_conjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count); 31 void _Copy_disjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count); 32 33 void _Copy_aligned_conjoint_words(HeapWord* from, HeapWord* to, size_t count); 34 void _Copy_aligned_disjoint_words(HeapWord* from, HeapWord* to, size_t count); 35 36 void _Copy_conjoint_bytes(void* from, void* to, size_t count); 37 38 void _Copy_conjoint_bytes_atomic (void* from, void* to, size_t count); 39 void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count); 40 void _Copy_conjoint_jints_atomic (jint* from, jint* to, size_t count); 41 void _Copy_conjoint_jlongs_atomic (jlong* from, jlong* to, size_t count); 42 void _Copy_conjoint_oops_atomic (oop* from, oop* to, size_t count); 43 44 void _Copy_arrayof_conjoint_bytes (HeapWord* from, HeapWord* to, size_t count); 45 void _Copy_arrayof_conjoint_jshorts(HeapWord* from, HeapWord* to, size_t count); 46 void _Copy_arrayof_conjoint_jints (HeapWord* from, HeapWord* to, size_t count); 47 void _Copy_arrayof_conjoint_jlongs (HeapWord* from, HeapWord* to, size_t count); 48 void _Copy_arrayof_conjoint_oops (HeapWord* from, HeapWord* to, size_t count); 49 } 50 51 class Copy : AllStatic { 52 public: 53 // Block copy methods have four attributes. We don't define all possibilities. 54 // alignment: aligned to BytesPerLong 55 // arrayof: arraycopy operation with both operands aligned on the same 56 // boundary as the first element of an array of the copy unit. 57 // This is currently a HeapWord boundary on all platforms, except 58 // for long and double arrays, which are aligned on an 8-byte 59 // boundary on all platforms. 60 // arraycopy operations are implicitly atomic on each array element. 61 // overlap: disjoint or conjoint. 62 // copy unit: bytes or words (i.e., HeapWords) or oops (i.e., pointers). 63 // atomicity: atomic or non-atomic on the copy unit. 64 // 65 // Names are constructed thusly: 66 // 67 // [ 'aligned_' | 'arrayof_' ] 68 // ('conjoint_' | 'disjoint_') 69 // ('words' | 'bytes' | 'jshorts' | 'jints' | 'jlongs' | 'oops') 70 // [ '_atomic' ] 71 // 72 // Except in the arrayof case, whatever the alignment is, we assume we can copy 73 // whole alignment units. E.g., if BytesPerLong is 2x word alignment, an odd 74 // count may copy an extra word. In the arrayof case, we are allowed to copy 75 // only the number of copy units specified. 76 // 77 // All callees check count for 0. 78 // 79 80 // HeapWords 81 82 // Word-aligned words, conjoint, not atomic on each word 83 static void conjoint_words(HeapWord* from, HeapWord* to, size_t count) { 84 assert_params_ok(from, to, LogHeapWordSize); 85 pd_conjoint_words(from, to, count); 86 } 87 88 // Word-aligned words, disjoint, not atomic on each word 89 static void disjoint_words(HeapWord* from, HeapWord* to, size_t count) { 90 assert_params_ok(from, to, LogHeapWordSize); 91 assert_disjoint(from, to, count); 92 pd_disjoint_words(from, to, count); 93 } 94 95 // Word-aligned words, disjoint, atomic on each word 96 static void disjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count) { 97 assert_params_ok(from, to, LogHeapWordSize); 98 assert_disjoint(from, to, count); 99 pd_disjoint_words_atomic(from, to, count); 100 } 101 102 // Object-aligned words, conjoint, not atomic on each word 103 static void aligned_conjoint_words(HeapWord* from, HeapWord* to, size_t count) { 104 assert_params_aligned(from, to); 105 pd_aligned_conjoint_words(from, to, count); 106 } 107 108 // Object-aligned words, disjoint, not atomic on each word 109 static void aligned_disjoint_words(HeapWord* from, HeapWord* to, size_t count) { 110 assert_params_aligned(from, to); 111 assert_disjoint(from, to, count); 112 pd_aligned_disjoint_words(from, to, count); 113 } 114 115 // bytes, jshorts, jints, jlongs, oops 116 117 // bytes, conjoint, not atomic on each byte (not that it matters) 118 static void conjoint_jbytes(void* from, void* to, size_t count) { 119 pd_conjoint_bytes(from, to, count); 120 } 121 122 // bytes, conjoint, atomic on each byte (not that it matters) 123 static void conjoint_jbytes_atomic(void* from, void* to, size_t count) { 124 pd_conjoint_bytes(from, to, count); 125 } 126 127 // jshorts, conjoint, atomic on each jshort 128 static void conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) { 129 assert_params_ok(from, to, LogBytesPerShort); 130 pd_conjoint_jshorts_atomic(from, to, count); 131 } 132 133 // jints, conjoint, atomic on each jint 134 static void conjoint_jints_atomic(jint* from, jint* to, size_t count) { 135 assert_params_ok(from, to, LogBytesPerInt); 136 pd_conjoint_jints_atomic(from, to, count); 137 } 138 139 // jlongs, conjoint, atomic on each jlong 140 static void conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) { 141 assert_params_ok(from, to, LogBytesPerLong); 142 pd_conjoint_jlongs_atomic(from, to, count); 143 } 144 145 // oops, conjoint, atomic on each oop 146 static void conjoint_oops_atomic(oop* from, oop* to, size_t count) { 147 assert_params_ok(from, to, LogBytesPerHeapOop); 148 pd_conjoint_oops_atomic(from, to, count); 149 } 150 151 // overloaded for UseCompressedOops 152 static void conjoint_oops_atomic(narrowOop* from, narrowOop* to, size_t count) { 153 assert(sizeof(narrowOop) == sizeof(jint), "this cast is wrong"); 154 assert_params_ok(from, to, LogBytesPerInt); 155 pd_conjoint_jints_atomic((jint*)from, (jint*)to, count); 156 } 157 158 // Copy a span of memory. If the span is an integral number of aligned 159 // longs, words, or ints, copy those units atomically. 160 // The largest atomic transfer unit is 8 bytes, or the largest power 161 // of two which divides all of from, to, and size, whichever is smaller. 162 static void conjoint_memory_atomic(void* from, void* to, size_t size); 163 164 // bytes, conjoint array, atomic on each byte (not that it matters) 165 static void arrayof_conjoint_jbytes(HeapWord* from, HeapWord* to, size_t count) { 166 pd_arrayof_conjoint_bytes(from, to, count); 167 } 168 169 // jshorts, conjoint array, atomic on each jshort 170 static void arrayof_conjoint_jshorts(HeapWord* from, HeapWord* to, size_t count) { 171 assert_params_ok(from, to, LogBytesPerShort); 172 pd_arrayof_conjoint_jshorts(from, to, count); 173 } 174 175 // jints, conjoint array, atomic on each jint 176 static void arrayof_conjoint_jints(HeapWord* from, HeapWord* to, size_t count) { 177 assert_params_ok(from, to, LogBytesPerInt); 178 pd_arrayof_conjoint_jints(from, to, count); 179 } 180 181 // jlongs, conjoint array, atomic on each jlong 182 static void arrayof_conjoint_jlongs(HeapWord* from, HeapWord* to, size_t count) { 183 assert_params_ok(from, to, LogBytesPerLong); 184 pd_arrayof_conjoint_jlongs(from, to, count); 185 } 186 187 // oops, conjoint array, atomic on each oop 188 static void arrayof_conjoint_oops(HeapWord* from, HeapWord* to, size_t count) { 189 assert_params_ok(from, to, LogBytesPerHeapOop); 190 pd_arrayof_conjoint_oops(from, to, count); 191 } 192 193 // Known overlap methods 194 195 // Copy word-aligned words from higher to lower addresses, not atomic on each word 196 inline static void conjoint_words_to_lower(HeapWord* from, HeapWord* to, size_t byte_count) { 197 // byte_count is in bytes to check its alignment 198 assert_params_ok(from, to, LogHeapWordSize); 199 assert_byte_count_ok(byte_count, HeapWordSize); 200 201 size_t count = (size_t)round_to(byte_count, HeapWordSize) >> LogHeapWordSize; 202 assert(to <= from || from + count <= to, "do not overwrite source data"); 203 204 while (count-- > 0) { 205 *to++ = *from++; 206 } 207 } 208 209 // Copy word-aligned words from lower to higher addresses, not atomic on each word 210 inline static void conjoint_words_to_higher(HeapWord* from, HeapWord* to, size_t byte_count) { 211 // byte_count is in bytes to check its alignment 212 assert_params_ok(from, to, LogHeapWordSize); 213 assert_byte_count_ok(byte_count, HeapWordSize); 214 215 size_t count = (size_t)round_to(byte_count, HeapWordSize) >> LogHeapWordSize; 216 assert(from <= to || to + count <= from, "do not overwrite source data"); 217 218 from += count - 1; 219 to += count - 1; 220 while (count-- > 0) { 221 *to-- = *from--; 222 } 223 } 224 225 // Fill methods 226 227 // Fill word-aligned words, not atomic on each word 228 // set_words 229 static void fill_to_words(HeapWord* to, size_t count, juint value = 0) { 230 assert_params_ok(to, LogHeapWordSize); 231 pd_fill_to_words(to, count, value); 232 } 233 234 static void fill_to_aligned_words(HeapWord* to, size_t count, juint value = 0) { 235 assert_params_aligned(to); 236 pd_fill_to_aligned_words(to, count, value); 237 } 238 239 // Fill bytes 240 static void fill_to_bytes(void* to, size_t count, jubyte value = 0) { 241 pd_fill_to_bytes(to, count, value); 242 } 243 244 // Fill a span of memory. If the span is an integral number of aligned 245 // longs, words, or ints, store to those units atomically. 246 // The largest atomic transfer unit is 8 bytes, or the largest power 247 // of two which divides both to and size, whichever is smaller. 248 static void fill_to_memory_atomic(void* to, size_t size, jubyte value = 0); 249 250 // Zero-fill methods 251 252 // Zero word-aligned words, not atomic on each word 253 static void zero_to_words(HeapWord* to, size_t count) { 254 assert_params_ok(to, LogHeapWordSize); 255 pd_zero_to_words(to, count); 256 } 257 258 // Zero bytes 259 static void zero_to_bytes(void* to, size_t count) { 260 pd_zero_to_bytes(to, count); 261 } 262 263 private: 264 static bool params_disjoint(HeapWord* from, HeapWord* to, size_t count) { 265 if (from < to) { 266 return pointer_delta(to, from) >= count; 267 } 268 return pointer_delta(from, to) >= count; 269 } 270 271 // These methods raise a fatal if they detect a problem. 272 273 static void assert_disjoint(HeapWord* from, HeapWord* to, size_t count) { 274 #ifdef ASSERT 275 if (!params_disjoint(from, to, count)) 276 basic_fatal("source and dest overlap"); 277 #endif 278 } 279 280 static void assert_params_ok(void* from, void* to, intptr_t log_align) { 281 #ifdef ASSERT 282 if (mask_bits((uintptr_t)from, right_n_bits(log_align)) != 0) 283 basic_fatal("not aligned"); 284 if (mask_bits((uintptr_t)to, right_n_bits(log_align)) != 0) 285 basic_fatal("not aligned"); 286 #endif 287 } 288 289 static void assert_params_ok(HeapWord* to, intptr_t log_align) { 290 #ifdef ASSERT 291 if (mask_bits((uintptr_t)to, right_n_bits(log_align)) != 0) 292 basic_fatal("not word aligned"); 293 #endif 294 } 295 static void assert_params_aligned(HeapWord* from, HeapWord* to) { 296 #ifdef ASSERT 297 if (mask_bits((uintptr_t)from, BytesPerLong-1) != 0) 298 basic_fatal("not long aligned"); 299 if (mask_bits((uintptr_t)to, BytesPerLong-1) != 0) 300 basic_fatal("not long aligned"); 301 #endif 302 } 303 304 static void assert_params_aligned(HeapWord* to) { 305 #ifdef ASSERT 306 if (mask_bits((uintptr_t)to, BytesPerLong-1) != 0) 307 basic_fatal("not long aligned"); 308 #endif 309 } 310 311 static void assert_byte_count_ok(size_t byte_count, size_t unit_size) { 312 #ifdef ASSERT 313 if ((size_t)round_to(byte_count, unit_size) != byte_count) { 314 basic_fatal("byte count must be aligned"); 315 } 316 #endif 317 } 318 319 // Platform dependent implementations of the above methods. 320 #include "incls/_copy_pd.hpp.incl" 321 };