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 // HeapWords 78 79 // Word-aligned words, conjoint, not atomic on each word 80 static void conjoint_words(HeapWord* from, HeapWord* to, size_t count) { 81 assert_params_ok(from, to, LogHeapWordSize); 82 pd_conjoint_words(from, to, count); 83 } 84 85 // Word-aligned words, disjoint, not atomic on each word 86 static void disjoint_words(HeapWord* from, HeapWord* to, size_t count) { 87 assert_params_ok(from, to, LogHeapWordSize); 88 assert_disjoint(from, to, count); 89 pd_disjoint_words(from, to, count); 90 } 91 92 // Word-aligned words, disjoint, atomic on each word 93 static void disjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count) { 94 assert_params_ok(from, to, LogHeapWordSize); 95 assert_disjoint(from, to, count); 96 pd_disjoint_words_atomic(from, to, count); 97 } 98 99 // Object-aligned words, conjoint, not atomic on each word 100 static void aligned_conjoint_words(HeapWord* from, HeapWord* to, size_t count) { 101 assert_params_aligned(from, to); 102 assert_non_zero(count); 103 pd_aligned_conjoint_words(from, to, count); 104 } 105 106 // Object-aligned words, disjoint, not atomic on each word 107 static void aligned_disjoint_words(HeapWord* from, HeapWord* to, size_t count) { 108 assert_params_aligned(from, to); 109 assert_disjoint(from, to, count); 110 assert_non_zero(count); 111 pd_aligned_disjoint_words(from, to, count); 112 } 113 114 // bytes, jshorts, jints, jlongs, oops 115 116 // bytes, conjoint, not atomic on each byte (not that it matters) 117 static void conjoint_bytes(void* from, void* to, size_t count) { 118 assert_non_zero(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_bytes_atomic(void* from, void* to, size_t count) { 124 assert_non_zero(count); 125 pd_conjoint_bytes(from, to, count); 126 } 127 128 // jshorts, conjoint, atomic on each jshort 129 static void conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) { 130 assert_params_ok(from, to, LogBytesPerShort); 131 assert_non_zero(count); 132 pd_conjoint_jshorts_atomic(from, to, count); 133 } 134 135 // jints, conjoint, atomic on each jint 136 static void conjoint_jints_atomic(jint* from, jint* to, size_t count) { 137 assert_params_ok(from, to, LogBytesPerInt); 138 assert_non_zero(count); 139 pd_conjoint_jints_atomic(from, to, count); 140 } 141 142 // jlongs, conjoint, atomic on each jlong 143 static void conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) { 144 assert_params_ok(from, to, LogBytesPerLong); 145 assert_non_zero(count); 146 pd_conjoint_jlongs_atomic(from, to, count); 147 } 148 149 // oops, conjoint, atomic on each oop 150 static void conjoint_oops_atomic(oop* from, oop* to, size_t count) { 151 assert_params_ok(from, to, LogBytesPerHeapOop); 152 assert_non_zero(count); 153 pd_conjoint_oops_atomic(from, to, count); 154 } 155 156 // overloaded for UseCompressedOops 157 static void conjoint_oops_atomic(narrowOop* from, narrowOop* to, size_t count) { 158 assert(sizeof(narrowOop) == sizeof(jint), "this cast is wrong"); 159 assert_params_ok(from, to, LogBytesPerInt); 160 assert_non_zero(count); 161 pd_conjoint_jints_atomic((jint*)from, (jint*)to, count); 162 } 163 164 // Copy a span of memory. If the span is an integral number of aligned 165 // longs, words, or ints, copy those units atomically. 166 // The largest atomic transfer unit is 8 bytes, or the largest power 167 // of two which divides all of from, to, and size, whichever is smaller. 168 static void conjoint_memory_atomic(void* from, void* to, size_t size); 169 170 // bytes, conjoint array, atomic on each byte (not that it matters) 171 static void arrayof_conjoint_bytes(HeapWord* from, HeapWord* to, size_t count) { 172 assert_non_zero(count); 173 pd_arrayof_conjoint_bytes(from, to, count); 174 } 175 176 // jshorts, conjoint array, atomic on each jshort 177 static void arrayof_conjoint_jshorts(HeapWord* from, HeapWord* to, size_t count) { 178 assert_params_ok(from, to, LogBytesPerShort); 179 assert_non_zero(count); 180 pd_arrayof_conjoint_jshorts(from, to, count); 181 } 182 183 // jints, conjoint array, atomic on each jint 184 static void arrayof_conjoint_jints(HeapWord* from, HeapWord* to, size_t count) { 185 assert_params_ok(from, to, LogBytesPerInt); 186 assert_non_zero(count); 187 pd_arrayof_conjoint_jints(from, to, count); 188 } 189 190 // jlongs, conjoint array, atomic on each jlong 191 static void arrayof_conjoint_jlongs(HeapWord* from, HeapWord* to, size_t count) { 192 assert_params_ok(from, to, LogBytesPerLong); 193 assert_non_zero(count); 194 pd_arrayof_conjoint_jlongs(from, to, count); 195 } 196 197 // oops, conjoint array, atomic on each oop 198 static void arrayof_conjoint_oops(HeapWord* from, HeapWord* to, size_t count) { 199 assert_params_ok(from, to, LogBytesPerHeapOop); 200 assert_non_zero(count); 201 pd_arrayof_conjoint_oops(from, to, count); 202 } 203 204 // Known overlap methods 205 206 // Copy word-aligned words from higher to lower addresses, not atomic on each word 207 inline static void conjoint_words_to_lower(HeapWord* from, HeapWord* to, size_t byte_count) { 208 // byte_count is in bytes to check its alignment 209 assert_params_ok(from, to, LogHeapWordSize); 210 assert_byte_count_ok(byte_count, HeapWordSize); 211 212 size_t count = (size_t)round_to(byte_count, HeapWordSize) >> LogHeapWordSize; 213 assert(to <= from || from + count <= to, "do not overwrite source data"); 214 215 while (count-- > 0) { 216 *to++ = *from++; 217 } 218 } 219 220 // Copy word-aligned words from lower to higher addresses, not atomic on each word 221 inline static void conjoint_words_to_higher(HeapWord* from, HeapWord* to, size_t byte_count) { 222 // byte_count is in bytes to check its alignment 223 assert_params_ok(from, to, LogHeapWordSize); 224 assert_byte_count_ok(byte_count, HeapWordSize); 225 226 size_t count = (size_t)round_to(byte_count, HeapWordSize) >> LogHeapWordSize; 227 assert(from <= to || to + count <= from, "do not overwrite source data"); 228 229 from += count - 1; 230 to += count - 1; 231 while (count-- > 0) { 232 *to-- = *from--; 233 } 234 } 235 236 // Fill methods 237 238 // Fill word-aligned words, not atomic on each word 239 // set_words 240 static void fill_to_words(HeapWord* to, size_t count, juint value = 0) { 241 assert_params_ok(to, LogHeapWordSize); 242 pd_fill_to_words(to, count, value); 243 } 244 245 static void fill_to_aligned_words(HeapWord* to, size_t count, juint value = 0) { 246 assert_params_aligned(to); 247 pd_fill_to_aligned_words(to, count, value); 248 } 249 250 // Fill bytes 251 static void fill_to_bytes(void* to, size_t count, jubyte value = 0) { 252 pd_fill_to_bytes(to, count, value); 253 } 254 255 // Fill a span of memory. If the span is an integral number of aligned 256 // longs, words, or ints, store to those units atomically. 257 // The largest atomic transfer unit is 8 bytes, or the largest power 258 // of two which divides both to and size, whichever is smaller. 259 static void fill_to_memory_atomic(void* to, size_t size, jubyte value = 0); 260 261 // Zero-fill methods 262 263 // Zero word-aligned words, not atomic on each word 264 static void zero_to_words(HeapWord* to, size_t count) { 265 assert_params_ok(to, LogHeapWordSize); 266 pd_zero_to_words(to, count); 267 } 268 269 // Zero bytes 270 static void zero_to_bytes(void* to, size_t count) { 271 pd_zero_to_bytes(to, count); 272 } 273 274 private: 275 static bool params_disjoint(HeapWord* from, HeapWord* to, size_t count) { 276 if (from < to) { 277 return pointer_delta(to, from) >= count; 278 } 279 return pointer_delta(from, to) >= count; 280 } 281 282 // These methods raise a fatal if they detect a problem. 283 284 static void assert_disjoint(HeapWord* from, HeapWord* to, size_t count) { 285 #ifdef ASSERT 286 if (!params_disjoint(from, to, count)) 287 basic_fatal("source and dest overlap"); 288 #endif 289 } 290 291 static void assert_params_ok(void* from, void* to, intptr_t log_align) { 292 #ifdef ASSERT 293 if (mask_bits((uintptr_t)from, right_n_bits(log_align)) != 0) 294 basic_fatal("not aligned"); 295 if (mask_bits((uintptr_t)to, right_n_bits(log_align)) != 0) 296 basic_fatal("not aligned"); 297 #endif 298 } 299 300 static void assert_params_ok(HeapWord* to, intptr_t log_align) { 301 #ifdef ASSERT 302 if (mask_bits((uintptr_t)to, right_n_bits(log_align)) != 0) 303 basic_fatal("not word aligned"); 304 #endif 305 } 306 static void assert_params_aligned(HeapWord* from, HeapWord* to) { 307 #ifdef ASSERT 308 if (mask_bits((uintptr_t)from, BytesPerLong-1) != 0) 309 basic_fatal("not long aligned"); 310 if (mask_bits((uintptr_t)to, BytesPerLong-1) != 0) 311 basic_fatal("not long aligned"); 312 #endif 313 } 314 315 static void assert_params_aligned(HeapWord* to) { 316 #ifdef ASSERT 317 if (mask_bits((uintptr_t)to, BytesPerLong-1) != 0) 318 basic_fatal("not long aligned"); 319 #endif 320 } 321 322 static void assert_non_zero(size_t count) { 323 #ifdef ASSERT 324 if (count == 0) { 325 basic_fatal("count must be non-zero"); 326 } 327 #endif 328 } 329 330 static void assert_byte_count_ok(size_t byte_count, size_t unit_size) { 331 #ifdef ASSERT 332 if ((size_t)round_to(byte_count, unit_size) != byte_count) { 333 basic_fatal("byte count must be aligned"); 334 } 335 #endif 336 } 337 338 // Platform dependent implementations of the above methods. 339 #include "incls/_copy_pd.hpp.incl" 340 };