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/macros.hpp"
30
31 // Assembly code for platforms that need it.
32 extern "C" {
33 void _Copy_conjoint_words(HeapWord* from, HeapWord* to, size_t count);
34 void _Copy_disjoint_words(HeapWord* from, HeapWord* to, size_t count);
35
36 void _Copy_conjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count);
37 void _Copy_disjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count);
38
39 void _Copy_aligned_conjoint_words(HeapWord* from, HeapWord* to, size_t count);
40 void _Copy_aligned_disjoint_words(HeapWord* from, HeapWord* to, size_t count);
41
42 void _Copy_conjoint_bytes(void* from, void* to, size_t count);
43
44 void _Copy_conjoint_bytes_atomic (void* from, void* to, size_t count);
45 void _Copy_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count);
46 void _Copy_conjoint_jints_atomic (jint* from, jint* to, size_t count);
47 void _Copy_conjoint_jlongs_atomic (jlong* from, jlong* to, size_t count);
48 void _Copy_conjoint_oops_atomic (oop* from, oop* to, size_t count);
49
50 void _Copy_arrayof_conjoint_bytes (HeapWord* from, HeapWord* to, size_t count);
51 void _Copy_arrayof_conjoint_jshorts(HeapWord* from, HeapWord* to, size_t count);
52 void _Copy_arrayof_conjoint_jints (HeapWord* from, HeapWord* to, size_t count);
53 void _Copy_arrayof_conjoint_jlongs (HeapWord* from, HeapWord* to, size_t count);
54 void _Copy_arrayof_conjoint_oops (HeapWord* from, HeapWord* to, size_t count);
55 }
56
57 class Copy : AllStatic {
58 public:
59 // Block copy methods have four attributes. We don't define all possibilities.
60 // alignment: aligned to BytesPerLong
61 // arrayof: arraycopy operation with both operands aligned on the same
62 // boundary as the first element of an array of the copy unit.
63 // This is currently a HeapWord boundary on all platforms, except
64 // for long and double arrays, which are aligned on an 8-byte
65 // boundary on all platforms.
66 // arraycopy operations are implicitly atomic on each array element.
67 // overlap: disjoint or conjoint.
68 // copy unit: bytes or words (i.e., HeapWords) or oops (i.e., pointers).
69 // atomicity: atomic or non-atomic on the copy unit.
70 //
71 // Names are constructed thusly:
72 //
73 // [ 'aligned_' | 'arrayof_' ]
74 // ('conjoint_' | 'disjoint_')
75 // ('words' | 'bytes' | 'jshorts' | 'jints' | 'jlongs' | 'oops')
76 // [ '_atomic' ]
77 //
78 // Except in the arrayof case, whatever the alignment is, we assume we can copy
79 // whole alignment units. E.g., if BytesPerLong is 2x word alignment, an odd
80 // count may copy an extra word. In the arrayof case, we are allowed to copy
81 // only the number of copy units specified.
82 //
83 // All callees check count for 0.
84 //
85
86 // HeapWords
87
88 // Word-aligned words, conjoint, not atomic on each word
89 static void conjoint_words(HeapWord* from, HeapWord* to, size_t count) {
90 assert_params_ok(from, to, LogHeapWordSize);
91 pd_conjoint_words(from, to, count);
92 }
93
94 // Word-aligned words, disjoint, not atomic on each word
95 static void disjoint_words(HeapWord* from, HeapWord* to, size_t count) {
96 assert_params_ok(from, to, LogHeapWordSize);
97 assert_disjoint(from, to, count);
98 pd_disjoint_words(from, to, count);
99 }
100
101 // Word-aligned words, disjoint, atomic on each word
102 static void disjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count) {
103 assert_params_ok(from, to, LogHeapWordSize);
104 assert_disjoint(from, to, count);
105 pd_disjoint_words_atomic(from, to, count);
106 }
107
108 // Object-aligned words, conjoint, not atomic on each word
109 static void aligned_conjoint_words(HeapWord* from, HeapWord* to, size_t count) {
110 assert_params_aligned(from, to);
111 pd_aligned_conjoint_words(from, to, count);
112 }
113
114 // Object-aligned words, disjoint, not atomic on each word
115 static void aligned_disjoint_words(HeapWord* from, HeapWord* to, size_t count) {
116 assert_params_aligned(from, to);
117 assert_disjoint(from, to, count);
118 pd_aligned_disjoint_words(from, to, count);
119 }
120
121 // bytes, jshorts, jints, jlongs, oops
122
123 // bytes, conjoint, not atomic on each byte (not that it matters)
124 static void conjoint_jbytes(void* from, void* to, size_t count) {
125 pd_conjoint_bytes(from, to, count);
126 }
127
128 // bytes, conjoint, atomic on each byte (not that it matters)
129 static void conjoint_jbytes_atomic(void* from, void* to, size_t count) {
130 pd_conjoint_bytes(from, to, count);
131 }
132
133 // jshorts, conjoint, atomic on each jshort
134 static void conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
135 assert_params_ok(from, to, LogBytesPerShort);
136 pd_conjoint_jshorts_atomic(from, to, count);
137 }
138
139 // jints, conjoint, atomic on each jint
140 static void conjoint_jints_atomic(jint* from, jint* to, size_t count) {
141 assert_params_ok(from, to, LogBytesPerInt);
142 pd_conjoint_jints_atomic(from, to, count);
143 }
144
145 // jlongs, conjoint, atomic on each jlong
146 static void conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
147 assert_params_ok(from, to, LogBytesPerLong);
148 pd_conjoint_jlongs_atomic(from, to, count);
149 }
150
151 // oops, conjoint, atomic on each oop
152 static void conjoint_oops_atomic(oop* from, oop* to, size_t count) {
153 assert_params_ok(from, to, LogBytesPerHeapOop);
154 pd_conjoint_oops_atomic(from, to, count);
155 }
156
157 // overloaded for UseCompressedOops
158 static void conjoint_oops_atomic(narrowOop* from, narrowOop* to, size_t count) {
159 assert(sizeof(narrowOop) == sizeof(jint), "this cast is wrong");
160 assert_params_ok(from, to, LogBytesPerInt);
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_jbytes(HeapWord* from, HeapWord* to, size_t count) {
172 pd_arrayof_conjoint_bytes(from, to, count);
173 }
174
175 // jshorts, conjoint array, atomic on each jshort
176 static void arrayof_conjoint_jshorts(HeapWord* from, HeapWord* to, size_t count) {
177 assert_params_ok(from, to, LogBytesPerShort);
178 pd_arrayof_conjoint_jshorts(from, to, count);
179 }
180
181 // jints, conjoint array, atomic on each jint
182 static void arrayof_conjoint_jints(HeapWord* from, HeapWord* to, size_t count) {
183 assert_params_ok(from, to, LogBytesPerInt);
184 pd_arrayof_conjoint_jints(from, to, count);
185 }
186
187 // jlongs, conjoint array, atomic on each jlong
188 static void arrayof_conjoint_jlongs(HeapWord* from, HeapWord* to, size_t count) {
189 assert_params_ok(from, to, LogBytesPerLong);
190 pd_arrayof_conjoint_jlongs(from, to, count);
191 }
192
193 // oops, conjoint array, atomic on each oop
194 static void arrayof_conjoint_oops(HeapWord* from, HeapWord* to, size_t count) {
195 assert_params_ok(from, to, LogBytesPerHeapOop);
196 pd_arrayof_conjoint_oops(from, to, count);
197 }
198
199 // Known overlap methods
200
201 // Copy word-aligned words from higher to lower addresses, not atomic on each word
202 inline static void conjoint_words_to_lower(HeapWord* from, HeapWord* to, size_t byte_count) {
203 // byte_count is in bytes to check its alignment
204 assert_params_ok(from, to, LogHeapWordSize);
205 assert_byte_count_ok(byte_count, HeapWordSize);
206
207 size_t count = (size_t)round_to(byte_count, HeapWordSize) >> LogHeapWordSize;
208 assert(to <= from || from + count <= to, "do not overwrite source data");
209
210 while (count-- > 0) {
211 *to++ = *from++;
212 }
213 }
214
215 // Copy word-aligned words from lower to higher addresses, not atomic on each word
216 inline static void conjoint_words_to_higher(HeapWord* from, HeapWord* to, size_t byte_count) {
217 // byte_count is in bytes to check its alignment
218 assert_params_ok(from, to, LogHeapWordSize);
219 assert_byte_count_ok(byte_count, HeapWordSize);
220
221 size_t count = (size_t)round_to(byte_count, HeapWordSize) >> LogHeapWordSize;
222 assert(from <= to || to + count <= from, "do not overwrite source data");
223
224 from += count - 1;
225 to += count - 1;
226 while (count-- > 0) {
227 *to-- = *from--;
228 }
229 }
230
231 /**
232 * Copy and *unconditionally* byte swap elements
233 *
234 * @param src address of source
235 * @param dst address of destination
236 * @param byte_count number of bytes to copy
237 * @param elem_size size of the elements to copy-swap
238 */
239 static void conjoint_swap(address src, address dst, size_t byte_count, size_t elem_size);
240
241 // Fill methods
242
243 // Fill word-aligned words, not atomic on each word
244 // set_words
245 static void fill_to_words(HeapWord* to, size_t count, juint value = 0) {
246 assert_params_ok(to, LogHeapWordSize);
247 pd_fill_to_words(to, count, value);
248 }
249
250 static void fill_to_aligned_words(HeapWord* to, size_t count, juint value = 0) {
251 assert_params_aligned(to);
252 pd_fill_to_aligned_words(to, count, value);
253 }
254
255 // Fill bytes
256 static void fill_to_bytes(void* to, size_t count, jubyte value = 0) {
257 pd_fill_to_bytes(to, count, value);
258 }
259
260 // Fill a span of memory. If the span is an integral number of aligned
261 // longs, words, or ints, store to those units atomically.
262 // The largest atomic transfer unit is 8 bytes, or the largest power
263 // of two which divides both to and size, whichever is smaller.
264 static void fill_to_memory_atomic(void* to, size_t size, jubyte value = 0);
265
266 // Zero-fill methods
267
268 // Zero word-aligned words, not atomic on each word
269 static void zero_to_words(HeapWord* to, size_t count) {
270 assert_params_ok(to, LogHeapWordSize);
271 pd_zero_to_words(to, count);
272 }
273
274 // Zero bytes
275 static void zero_to_bytes(void* to, size_t count) {
276 pd_zero_to_bytes(to, count);
277 }
278
279 private:
280 static bool params_disjoint(HeapWord* from, HeapWord* to, size_t count) {
281 if (from < to) {
282 return pointer_delta(to, from) >= count;
283 }
284 return pointer_delta(from, to) >= count;
285 }
286
287 // These methods raise a fatal if they detect a problem.
288
289 static void assert_disjoint(HeapWord* from, HeapWord* to, size_t count) {
290 #ifdef ASSERT
291 if (!params_disjoint(from, to, count))
292 basic_fatal("source and dest overlap");
293 #endif
294 }
295
296 static void assert_params_ok(void* from, void* to, intptr_t log_align) {
297 #ifdef ASSERT
298 if (mask_bits((uintptr_t)from, right_n_bits(log_align)) != 0)
299 basic_fatal("not aligned");
300 if (mask_bits((uintptr_t)to, right_n_bits(log_align)) != 0)
301 basic_fatal("not aligned");
302 #endif
303 }
304
305 static void assert_params_ok(HeapWord* to, intptr_t log_align) {
306 #ifdef ASSERT
307 if (mask_bits((uintptr_t)to, right_n_bits(log_align)) != 0)
308 basic_fatal("not word aligned");
309 #endif
310 }
311 static void assert_params_aligned(HeapWord* from, HeapWord* to) {
312 #ifdef ASSERT
313 if (mask_bits((uintptr_t)from, BytesPerLong-1) != 0)
314 basic_fatal("not long aligned");
315 if (mask_bits((uintptr_t)to, BytesPerLong-1) != 0)
316 basic_fatal("not long aligned");
317 #endif
318 }
319
320 static void assert_params_aligned(HeapWord* to) {
321 #ifdef ASSERT
322 if (mask_bits((uintptr_t)to, BytesPerLong-1) != 0)
323 basic_fatal("not long aligned");
324 #endif
325 }
326
327 static void assert_byte_count_ok(size_t byte_count, size_t unit_size) {
328 #ifdef ASSERT
329 if ((size_t)round_to(byte_count, unit_size) != byte_count) {
330 basic_fatal("byte count must be aligned");
331 }
332 #endif
333 }
334
335 // Platform dependent implementations of the above methods.
336 #include CPU_HEADER(copy)
337
338 };
339
340 #endif // SHARE_VM_UTILITIES_COPY_HPP