1 /*
2 * Copyright (c) 2003, 2016, 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 #ifndef SHARE_VM_UTILITIES_COPY_HPP
26 #define SHARE_VM_UTILITIES_COPY_HPP
27
28 #include "runtime/stubRoutines.hpp"
29 #include "utilities/align.hpp"
30 #include "utilities/macros.hpp"
31
32 // Assembly code for platforms that need it.
33 extern "C" {
34 void _Copy_conjoint_words(HeapWord* from, HeapWord* to, size_t count);
35 void _Copy_disjoint_words(HeapWord* from, HeapWord* to, size_t count);
36
37 void _Copy_conjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count);
38 void _Copy_disjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count);
39
40 void _Copy_aligned_conjoint_words(HeapWord* from, HeapWord* to, size_t count);
41 void _Copy_aligned_disjoint_words(HeapWord* from, HeapWord* to, size_t count);
42
43 void _Copy_conjoint_bytes(void* from, void* to, size_t count);
44
45 void _Copy_conjoint_bytes_atomic (void* from, void* to, size_t count);
46 void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count);
47 void _Copy_conjoint_jints_atomic (jint* from, jint* to, size_t count);
48 void _Copy_conjoint_jlongs_atomic (jlong* from, jlong* to, size_t count);
49 void _Copy_conjoint_oops_atomic (oop* from, oop* to, size_t count);
50
51 void _Copy_arrayof_conjoint_bytes (HeapWord* from, HeapWord* to, size_t count);
52 void _Copy_arrayof_conjoint_jshorts(HeapWord* from, HeapWord* to, size_t count);
53 void _Copy_arrayof_conjoint_jints (HeapWord* from, HeapWord* to, size_t count);
54 void _Copy_arrayof_conjoint_jlongs (HeapWord* from, HeapWord* to, size_t count);
55 void _Copy_arrayof_conjoint_oops (HeapWord* from, HeapWord* to, size_t count);
56 }
57
58 class Copy : AllStatic {
59 public:
60 // Block copy methods have four attributes. We don't define all possibilities.
61 // alignment: aligned to BytesPerLong
62 // arrayof: arraycopy operation with both operands aligned on the same
63 // boundary as the first element of an array of the copy unit.
64 // This is currently a HeapWord boundary on all platforms, except
65 // for long and double arrays, which are aligned on an 8-byte
66 // boundary on all platforms.
67 // arraycopy operations are implicitly atomic on each array element.
68 // overlap: disjoint or conjoint.
69 // copy unit: bytes or words (i.e., HeapWords) or oops (i.e., pointers).
70 // atomicity: atomic or non-atomic on the copy unit.
71 //
72 // Names are constructed thusly:
73 //
74 // [ 'aligned_' | 'arrayof_' ]
75 // ('conjoint_' | 'disjoint_')
76 // ('words' | 'bytes' | 'jshorts' | 'jints' | 'jlongs' | 'oops')
77 // [ '_atomic' ]
78 //
79 // Except in the arrayof case, whatever the alignment is, we assume we can copy
80 // whole alignment units. E.g., if BytesPerLong is 2x word alignment, an odd
81 // count may copy an extra word. In the arrayof case, we are allowed to copy
82 // only the number of copy units specified.
83 //
84 // All callees check count for 0.
85 //
86
87 // HeapWords
88
89 // Word-aligned words, conjoint, not atomic on each word
90 static void conjoint_words(HeapWord* from, HeapWord* to, size_t count) {
91 assert_params_ok(from, to, LogHeapWordSize);
92 pd_conjoint_words(from, to, count);
93 }
94
95 // Word-aligned words, disjoint, not atomic on each word
96 static void disjoint_words(HeapWord* from, HeapWord* to, size_t count) {
97 assert_params_ok(from, to, LogHeapWordSize);
98 assert_disjoint(from, to, count);
99 pd_disjoint_words(from, to, count);
100 }
101
102 // Word-aligned words, disjoint, atomic on each word
103 static void disjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count) {
104 assert_params_ok(from, to, LogHeapWordSize);
105 assert_disjoint(from, to, count);
106 pd_disjoint_words_atomic(from, to, count);
107 }
108
109 // Object-aligned words, conjoint, not atomic on each word
110 static void aligned_conjoint_words(HeapWord* from, HeapWord* to, size_t count) {
111 assert_params_aligned(from, to);
112 pd_aligned_conjoint_words(from, to, count);
113 }
114
115 // Object-aligned words, disjoint, not atomic on each word
116 static void aligned_disjoint_words(HeapWord* from, HeapWord* to, size_t count) {
117 assert_params_aligned(from, to);
118 assert_disjoint(from, to, count);
119 pd_aligned_disjoint_words(from, to, count);
120 }
121
122 // bytes, jshorts, jints, jlongs, oops
123
124 // bytes, conjoint, not atomic on each byte (not that it matters)
125 static void conjoint_jbytes(void* from, void* to, size_t count) {
126 pd_conjoint_bytes(from, to, count);
127 }
128
129 // bytes, conjoint, atomic on each byte (not that it matters)
130 static void conjoint_jbytes_atomic(void* from, void* to, size_t count) {
131 pd_conjoint_bytes(from, to, count);
132 }
133
134 // jshorts, conjoint, atomic on each jshort
135 static void conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
136 assert_params_ok(from, to, LogBytesPerShort);
137 pd_conjoint_jshorts_atomic(from, to, count);
138 }
139
140 // jints, conjoint, atomic on each jint
141 static void conjoint_jints_atomic(jint* from, jint* to, size_t count) {
142 assert_params_ok(from, to, LogBytesPerInt);
143 pd_conjoint_jints_atomic(from, to, count);
144 }
145
146 // jlongs, conjoint, atomic on each jlong
147 static void conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
148 assert_params_ok(from, to, LogBytesPerLong);
149 pd_conjoint_jlongs_atomic(from, to, count);
150 }
151
152 // oops, conjoint, atomic on each oop
153 static void conjoint_oops_atomic(oop* from, oop* to, size_t count) {
154 assert_params_ok(from, to, LogBytesPerHeapOop);
155 pd_conjoint_oops_atomic(from, to, count);
156 }
157
158 // overloaded for UseCompressedOops
159 static void conjoint_oops_atomic(narrowOop* from, narrowOop* to, size_t count) {
160 assert(sizeof(narrowOop) == sizeof(jint), "this cast is wrong");
161 assert_params_ok(from, to, LogBytesPerInt);
162 pd_conjoint_jints_atomic((jint*)from, (jint*)to, count);
163 }
164
165 // Copy a span of memory. If the span is an integral number of aligned
166 // longs, words, or ints, copy those units atomically.
167 // The largest atomic transfer unit is 8 bytes, or the largest power
168 // of two which divides all of from, to, and size, whichever is smaller.
169 static void conjoint_memory_atomic(void* from, void* to, size_t size);
170
171 // bytes, conjoint array, atomic on each byte (not that it matters)
172 static void arrayof_conjoint_jbytes(HeapWord* from, HeapWord* to, size_t 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 pd_arrayof_conjoint_jshorts(from, to, count);
180 }
181
182 // jints, conjoint array, atomic on each jint
183 static void arrayof_conjoint_jints(HeapWord* from, HeapWord* to, size_t count) {
184 assert_params_ok(from, to, LogBytesPerInt);
185 pd_arrayof_conjoint_jints(from, to, count);
186 }
187
188 // jlongs, conjoint array, atomic on each jlong
189 static void arrayof_conjoint_jlongs(HeapWord* from, HeapWord* to, size_t count) {
190 assert_params_ok(from, to, LogBytesPerLong);
191 pd_arrayof_conjoint_jlongs(from, to, count);
192 }
193
194 // oops, conjoint array, atomic on each oop
195 static void arrayof_conjoint_oops(HeapWord* from, HeapWord* to, size_t count) {
196 assert_params_ok(from, to, LogBytesPerHeapOop);
197 pd_arrayof_conjoint_oops(from, to, count);
198 }
199
200 // Known overlap methods
201
202 // Copy word-aligned words from higher to lower addresses, not atomic on each word
203 inline static void conjoint_words_to_lower(HeapWord* from, HeapWord* to, size_t byte_count) {
204 // byte_count is in bytes to check its alignment
205 assert_params_ok(from, to, LogHeapWordSize);
206 assert_byte_count_ok(byte_count, HeapWordSize);
207
208 size_t count = align_up(byte_count, HeapWordSize) >> LogHeapWordSize;
209 assert(to <= from || from + count <= to, "do not overwrite source data");
210
211 while (count-- > 0) {
212 *to++ = *from++;
213 }
214 }
215
216 // Copy word-aligned words from lower to higher addresses, not atomic on each word
217 inline static void conjoint_words_to_higher(HeapWord* from, HeapWord* to, size_t byte_count) {
218 // byte_count is in bytes to check its alignment
219 assert_params_ok(from, to, LogHeapWordSize);
220 assert_byte_count_ok(byte_count, HeapWordSize);
221
222 size_t count = align_up(byte_count, HeapWordSize) >> LogHeapWordSize;
223 assert(from <= to || to + count <= from, "do not overwrite source data");
224
225 from += count - 1;
226 to += count - 1;
227 while (count-- > 0) {
228 *to-- = *from--;
229 }
230 }
231
232 /**
233 * Copy elements
234 *
235 * @param src address of source
236 * @param dst address of destination
237 * @param byte_count number of bytes to copy
238 * @param elem_size size of the elements to copy-swap
239 */
240 static void conjoint_copy(const void* src, void* dst, size_t byte_count, size_t elem_size);
241
242 /**
243 * Copy and *unconditionally* byte swap elements
244 *
245 * @param src address of source
246 * @param dst address of destination
247 * @param byte_count number of bytes to copy
248 * @param elem_size size of the elements to copy-swap
249 */
250 static void conjoint_swap(const void* src, void* dst, size_t byte_count, size_t elem_size);
251
252 /**
253 * Copy and byte swap elements from the specified endian to the native (cpu) endian if needed (if they differ)
254 *
255 * @param src address of source
256 * @param dst address of destination
257 * @param byte_count number of bytes to copy
258 * @param elem_size size of the elements to copy-swap
259 */
260 template <Endian::Order endian>
261 static void conjoint_swap_if_needed(const void* src, void* dst, size_t byte_count, size_t elem_size) {
262 if (Endian::NATIVE != endian) {
263 conjoint_swap(src, dst, byte_count, elem_size);
264 } else {
265 conjoint_copy(src, dst, byte_count, elem_size);
266 }
267 }
268
269 // Fill methods
270
271 // Fill word-aligned words, not atomic on each word
272 // set_words
273 static void fill_to_words(HeapWord* to, size_t count, juint value = 0) {
274 assert_params_ok(to, LogHeapWordSize);
275 pd_fill_to_words(to, count, value);
276 }
277
278 static void fill_to_aligned_words(HeapWord* to, size_t count, juint value = 0) {
279 assert_params_aligned(to);
280 pd_fill_to_aligned_words(to, count, value);
281 }
282
283 // Fill bytes
284 static void fill_to_bytes(void* to, size_t count, jubyte value = 0) {
285 pd_fill_to_bytes(to, count, value);
286 }
287
288 // Fill a span of memory. If the span is an integral number of aligned
289 // longs, words, or ints, store to those units atomically.
290 // The largest atomic transfer unit is 8 bytes, or the largest power
291 // of two which divides both to and size, whichever is smaller.
292 static void fill_to_memory_atomic(void* to, size_t size, jubyte value = 0);
293
294 // Zero-fill methods
295
296 // Zero word-aligned words, not atomic on each word
297 static void zero_to_words(HeapWord* to, size_t count) {
298 assert_params_ok(to, LogHeapWordSize);
299 pd_zero_to_words(to, count);
300 }
301
302 // Zero bytes
303 static void zero_to_bytes(void* to, size_t count) {
304 pd_zero_to_bytes(to, count);
305 }
306
307 private:
308 static bool params_disjoint(HeapWord* from, HeapWord* to, size_t count) {
309 if (from < to) {
310 return pointer_delta(to, from) >= count;
311 }
312 return pointer_delta(from, to) >= count;
313 }
314
315 // These methods raise a fatal if they detect a problem.
316
317 static void assert_disjoint(HeapWord* from, HeapWord* to, size_t count) {
318 #ifdef ASSERT
319 if (!params_disjoint(from, to, count))
320 basic_fatal("source and dest overlap");
321 #endif
322 }
323
324 static void assert_params_ok(void* from, void* to, intptr_t log_align) {
325 #ifdef ASSERT
326 if (mask_bits((uintptr_t)from, right_n_bits(log_align)) != 0)
327 basic_fatal("not aligned");
328 if (mask_bits((uintptr_t)to, right_n_bits(log_align)) != 0)
329 basic_fatal("not aligned");
330 #endif
331 }
332
333 static void assert_params_ok(HeapWord* to, intptr_t log_align) {
334 #ifdef ASSERT
335 if (mask_bits((uintptr_t)to, right_n_bits(log_align)) != 0)
336 basic_fatal("not word aligned");
337 #endif
338 }
339 static void assert_params_aligned(HeapWord* from, HeapWord* to) {
340 #ifdef ASSERT
341 if (mask_bits((uintptr_t)from, BytesPerLong-1) != 0)
342 basic_fatal("not long aligned");
343 if (mask_bits((uintptr_t)to, BytesPerLong-1) != 0)
344 basic_fatal("not long aligned");
345 #endif
346 }
347
348 static void assert_params_aligned(HeapWord* to) {
349 #ifdef ASSERT
350 if (mask_bits((uintptr_t)to, BytesPerLong-1) != 0)
351 basic_fatal("not long aligned");
352 #endif
353 }
354
355 static void assert_byte_count_ok(size_t byte_count, size_t unit_size) {
356 #ifdef ASSERT
357 if (!is_aligned(byte_count, unit_size)) {
358 basic_fatal("byte count must be aligned");
359 }
360 #endif
361 }
362
363 // Platform dependent implementations of the above methods.
364 #include CPU_HEADER(copy)
365
366 };
367
368 #endif // SHARE_VM_UTILITIES_COPY_HPP