1 /*
2 * Copyright (c) 2000, 2021, 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 #include "precompiled.hpp"
26 #include "jni.h"
27 #include "jvm.h"
28 #include "classfile/classFileStream.hpp"
29 #include "classfile/classLoader.hpp"
30 #include "classfile/classLoadInfo.hpp"
31 #include "classfile/javaClasses.inline.hpp"
32 #include "classfile/systemDictionary.hpp"
33 #include "classfile/vmSymbols.hpp"
34 #include "jfr/jfrEvents.hpp"
35 #include "memory/allocation.inline.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "logging/log.hpp"
38 #include "logging/logStream.hpp"
39 #include "oops/access.inline.hpp"
40 #include "oops/fieldStreams.inline.hpp"
41 #include "oops/flatArrayKlass.hpp"
42 #include "oops/flatArrayOop.inline.hpp"
43 #include "oops/inlineKlass.inline.hpp"
44 #include "oops/instanceKlass.inline.hpp"
45 #include "oops/klass.inline.hpp"
46 #include "oops/objArrayOop.inline.hpp"
47 #include "oops/oop.inline.hpp"
48 #include "oops/typeArrayOop.inline.hpp"
49 #include "prims/jvmtiExport.hpp"
50 #include "prims/unsafe.hpp"
51 #include "runtime/fieldDescriptor.inline.hpp"
52 #include "runtime/globals.hpp"
53 #include "runtime/handles.inline.hpp"
54 #include "runtime/interfaceSupport.inline.hpp"
55 #include "runtime/jniHandles.inline.hpp"
56 #include "runtime/orderAccess.hpp"
57 #include "runtime/reflection.hpp"
58 #include "runtime/sharedRuntime.hpp"
59 #include "runtime/stubRoutines.hpp"
60 #include "runtime/thread.hpp"
61 #include "runtime/threadSMR.hpp"
62 #include "runtime/vmOperations.hpp"
63 #include "runtime/vm_version.hpp"
64 #include "services/threadService.hpp"
65 #include "utilities/align.hpp"
66 #include "utilities/copy.hpp"
67 #include "utilities/dtrace.hpp"
68 #include "utilities/macros.hpp"
69
70 /**
71 * Implementation of the jdk.internal.misc.Unsafe class
72 */
73
74
75 #define MAX_OBJECT_SIZE \
76 ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
77 + ((julong)max_jint * sizeof(double)) )
78
79
80 #define UNSAFE_ENTRY(result_type, header) \
81 JVM_ENTRY(static result_type, header)
82
83 #define UNSAFE_LEAF(result_type, header) \
84 JVM_LEAF(static result_type, header)
85
86 #define UNSAFE_END JVM_END
87
88
89 static inline void* addr_from_java(jlong addr) {
90 // This assert fails in a variety of ways on 32-bit systems.
91 // It is impossible to predict whether native code that converts
92 // pointers to longs will sign-extend or zero-extend the addresses.
93 //assert(addr == (uintptr_t)addr, "must not be odd high bits");
94 return (void*)(uintptr_t)addr;
95 }
96
97 static inline jlong addr_to_java(void* p) {
98 assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
99 return (uintptr_t)p;
100 }
101
102
103 // Note: The VM's obj_field and related accessors use byte-scaled
104 // ("unscaled") offsets, just as the unsafe methods do.
105
106 // However, the method Unsafe.fieldOffset explicitly declines to
107 // guarantee this. The field offset values manipulated by the Java user
108 // through the Unsafe API are opaque cookies that just happen to be byte
109 // offsets. We represent this state of affairs by passing the cookies
110 // through conversion functions when going between the VM and the Unsafe API.
111 // The conversion functions just happen to be no-ops at present.
112
113 static inline jlong field_offset_to_byte_offset(jlong field_offset) {
114 return field_offset;
115 }
116
117 static inline jlong field_offset_from_byte_offset(jlong byte_offset) {
118 return byte_offset;
119 }
120
121 static inline void assert_field_offset_sane(oop p, jlong field_offset) {
122 #ifdef ASSERT
123 jlong byte_offset = field_offset_to_byte_offset(field_offset);
124
125 if (p != NULL) {
126 assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
127 if (byte_offset == (jint)byte_offset) {
128 void* ptr_plus_disp = cast_from_oop<address>(p) + byte_offset;
129 assert(p->field_addr<void>((jint)byte_offset) == ptr_plus_disp,
130 "raw [ptr+disp] must be consistent with oop::field_addr");
131 }
132 jlong p_size = HeapWordSize * (jlong)(p->size());
133 assert(byte_offset < p_size, "Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, (int64_t)byte_offset, (int64_t)p_size);
134 }
135 #endif
136 }
137
138 static inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
139 assert_field_offset_sane(p, field_offset);
140 jlong byte_offset = field_offset_to_byte_offset(field_offset);
141
142 if (sizeof(char*) == sizeof(jint)) { // (this constant folds!)
143 return cast_from_oop<address>(p) + (jint) byte_offset;
144 } else {
145 return cast_from_oop<address>(p) + byte_offset;
146 }
147 }
148
149 // Externally callable versions:
150 // (Use these in compiler intrinsics which emulate unsafe primitives.)
151 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
152 return field_offset;
153 }
154 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
155 return byte_offset;
156 }
157
158 ///// Data read/writes on the Java heap and in native (off-heap) memory
159
160 /**
161 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access()
162 */
163 class GuardUnsafeAccess {
164 JavaThread* _thread;
165
166 public:
167 GuardUnsafeAccess(JavaThread* thread) : _thread(thread) {
168 // native/off-heap access which may raise SIGBUS if accessing
169 // memory mapped file data in a region of the file which has
170 // been truncated and is now invalid.
171 _thread->set_doing_unsafe_access(true);
172 }
173
174 ~GuardUnsafeAccess() {
175 _thread->set_doing_unsafe_access(false);
176 }
177 };
178
179 /**
180 * Helper class for accessing memory.
181 *
182 * Normalizes values and wraps accesses in
183 * JavaThread::doing_unsafe_access() if needed.
184 */
185 template <typename T>
186 class MemoryAccess : StackObj {
187 JavaThread* _thread;
188 oop _obj;
189 ptrdiff_t _offset;
190
191 // Resolves and returns the address of the memory access.
192 // This raw memory access may fault, so we make sure it happens within the
193 // guarded scope by making the access volatile at least. Since the store
194 // of Thread::set_doing_unsafe_access() is also volatile, these accesses
195 // can not be reordered by the compiler. Therefore, if the access triggers
196 // a fault, we will know that Thread::doing_unsafe_access() returns true.
197 volatile T* addr() {
198 void* addr = index_oop_from_field_offset_long(_obj, _offset);
199 return static_cast<volatile T*>(addr);
200 }
201
202 template <typename U>
203 U normalize_for_write(U x) {
204 return x;
205 }
206
207 jboolean normalize_for_write(jboolean x) {
208 return x & 1;
209 }
210
211 template <typename U>
212 U normalize_for_read(U x) {
213 return x;
214 }
215
216 jboolean normalize_for_read(jboolean x) {
217 return x != 0;
218 }
219
220 public:
221 MemoryAccess(JavaThread* thread, jobject obj, jlong offset)
222 : _thread(thread), _obj(JNIHandles::resolve(obj)), _offset((ptrdiff_t)offset) {
223 assert_field_offset_sane(_obj, offset);
224 }
225
226 T get() {
227 GuardUnsafeAccess guard(_thread);
228 return normalize_for_read(*addr());
229 }
230
231 void put(T x) {
232 GuardUnsafeAccess guard(_thread);
233 assert(_obj == NULL || !_obj->is_inline_type() || _obj->mark().is_larval_state(), "must be an object instance or a larval inline type");
234 *addr() = normalize_for_write(x);
235 }
236
237 T get_volatile() {
238 GuardUnsafeAccess guard(_thread);
239 volatile T ret = RawAccess<MO_SEQ_CST>::load(addr());
240 return normalize_for_read(ret);
241 }
242
243 void put_volatile(T x) {
244 GuardUnsafeAccess guard(_thread);
245 RawAccess<MO_SEQ_CST>::store(addr(), normalize_for_write(x));
246 }
247 };
248
249 #ifdef ASSERT
250 /*
251 * Get the field descriptor of the field of the given object at the given offset.
252 */
253 static bool get_field_descriptor(oop p, jlong offset, fieldDescriptor* fd) {
254 bool found = false;
255 Klass* k = p->klass();
256 if (k->is_instance_klass()) {
257 InstanceKlass* ik = InstanceKlass::cast(k);
258 found = ik->find_field_from_offset((int)offset, false, fd);
259 if (!found && ik->is_mirror_instance_klass()) {
260 Klass* k2 = java_lang_Class::as_Klass(p);
261 if (k2->is_instance_klass()) {
262 ik = InstanceKlass::cast(k2);
263 found = ik->find_field_from_offset((int)offset, true, fd);
264 }
265 }
266 }
267 return found;
268 }
269 #endif // ASSERT
270
271 static void assert_and_log_unsafe_value_access(oop p, jlong offset, InlineKlass* vk) {
272 Klass* k = p->klass();
273 #ifdef ASSERT
274 if (k->is_instance_klass()) {
275 assert_field_offset_sane(p, offset);
276 fieldDescriptor fd;
277 bool found = get_field_descriptor(p, offset, &fd);
278 if (found) {
279 assert(found, "value field not found");
280 assert(fd.is_inlined(), "field not flat");
281 } else {
282 if (log_is_enabled(Trace, valuetypes)) {
283 log_trace(valuetypes)("not a field in %s at offset " UINT64_FORMAT_X,
284 p->klass()->external_name(), (uint64_t)offset);
285 }
286 }
287 } else if (k->is_flatArray_klass()) {
288 FlatArrayKlass* vak = FlatArrayKlass::cast(k);
289 int index = (offset - vak->array_header_in_bytes()) / vak->element_byte_size();
290 address dest = (address)((flatArrayOop)p)->value_at_addr(index, vak->layout_helper());
291 assert(dest == (cast_from_oop<address>(p) + offset), "invalid offset");
292 } else {
293 ShouldNotReachHere();
294 }
295 #endif // ASSERT
296 if (log_is_enabled(Trace, valuetypes)) {
297 if (k->is_flatArray_klass()) {
298 FlatArrayKlass* vak = FlatArrayKlass::cast(k);
299 int index = (offset - vak->array_header_in_bytes()) / vak->element_byte_size();
300 address dest = (address)((flatArrayOop)p)->value_at_addr(index, vak->layout_helper());
301 log_trace(valuetypes)("%s array type %s index %d element size %d offset " UINT64_FORMAT_X " at " INTPTR_FORMAT,
302 p->klass()->external_name(), vak->external_name(),
303 index, vak->element_byte_size(), (uint64_t)offset, p2i(dest));
304 } else {
305 log_trace(valuetypes)("%s field type %s at offset " UINT64_FORMAT_X,
306 p->klass()->external_name(), vk->external_name(), (uint64_t)offset);
307 }
308 }
309 }
310
311 // These functions allow a null base pointer with an arbitrary address.
312 // But if the base pointer is non-null, the offset should make some sense.
313 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
314 UNSAFE_ENTRY(jobject, Unsafe_GetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
315 oop p = JNIHandles::resolve(obj);
316 assert_field_offset_sane(p, offset);
317 oop v = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
318 return JNIHandles::make_local(THREAD, v);
319 } UNSAFE_END
320
321 UNSAFE_ENTRY(void, Unsafe_PutReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
322 oop x = JNIHandles::resolve(x_h);
323 oop p = JNIHandles::resolve(obj);
324 assert_field_offset_sane(p, offset);
325 assert(!p->is_inline_type() || p->mark().is_larval_state(), "must be an object instance or a larval inline type");
326 HeapAccess<ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
327 } UNSAFE_END
328
329 UNSAFE_ENTRY(jlong, Unsafe_ValueHeaderSize(JNIEnv *env, jobject unsafe, jclass c)) {
330 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(c));
331 InlineKlass* vk = InlineKlass::cast(k);
332 return vk->first_field_offset();
333 } UNSAFE_END
334
335 UNSAFE_ENTRY(jboolean, Unsafe_IsFlattenedField(JNIEnv *env, jobject unsafe, jobject o)) {
336 oop f = JNIHandles::resolve_non_null(o);
337 Klass* k = java_lang_Class::as_Klass(java_lang_reflect_Field::clazz(f));
338 int slot = java_lang_reflect_Field::slot(f);
339 return InstanceKlass::cast(k)->field_is_inlined(slot);
340 } UNSAFE_END
341
342 UNSAFE_ENTRY(jboolean, Unsafe_IsFlattenedArray(JNIEnv *env, jobject unsafe, jclass c)) {
343 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(c));
344 return k->is_flatArray_klass();
345 } UNSAFE_END
346
347 UNSAFE_ENTRY(jobject, Unsafe_UninitializedDefaultValue(JNIEnv *env, jobject unsafe, jclass vc)) {
348 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(vc));
349 InlineKlass* vk = InlineKlass::cast(k);
350 oop v = vk->default_value();
351 return JNIHandles::make_local(THREAD, v);
352 } UNSAFE_END
353
354 UNSAFE_ENTRY(jobject, Unsafe_GetValue(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jclass vc)) {
355 oop base = JNIHandles::resolve(obj);
356 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(vc));
357 InlineKlass* vk = InlineKlass::cast(k);
358 assert_and_log_unsafe_value_access(base, offset, vk);
359 Handle base_h(THREAD, base);
360 oop v = vk->read_inlined_field(base_h(), offset, CHECK_NULL);
361 return JNIHandles::make_local(THREAD, v);
362 } UNSAFE_END
363
364 UNSAFE_ENTRY(void, Unsafe_PutValue(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jclass vc, jobject value)) {
365 oop base = JNIHandles::resolve(obj);
366 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(vc));
367 InlineKlass* vk = InlineKlass::cast(k);
368 assert(!base->is_inline_type() || base->mark().is_larval_state(), "must be an object instance or a larval inline type");
369 assert_and_log_unsafe_value_access(base, offset, vk);
370 oop v = JNIHandles::resolve(value);
371 vk->write_inlined_field(base, offset, v, CHECK);
372 } UNSAFE_END
373
374 UNSAFE_ENTRY(jobject, Unsafe_MakePrivateBuffer(JNIEnv *env, jobject unsafe, jobject value)) {
375 oop v = JNIHandles::resolve_non_null(value);
376 assert(v->is_inline_type(), "must be an inline type instance");
377 Handle vh(THREAD, v);
378 InlineKlass* vk = InlineKlass::cast(v->klass());
379 instanceOop new_value = vk->allocate_instance_buffer(CHECK_NULL);
380 vk->inline_copy_oop_to_new_oop(vh(), new_value);
381 markWord mark = new_value->mark();
382 new_value->set_mark(mark.enter_larval_state());
383 return JNIHandles::make_local(THREAD, new_value);
384 } UNSAFE_END
385
386 UNSAFE_ENTRY(jobject, Unsafe_FinishPrivateBuffer(JNIEnv *env, jobject unsafe, jobject value)) {
387 oop v = JNIHandles::resolve(value);
388 assert(v->mark().is_larval_state(), "must be a larval value");
389 markWord mark = v->mark();
390 v->set_mark(mark.exit_larval_state());
391 return JNIHandles::make_local(THREAD, v);
392 } UNSAFE_END
393
394 UNSAFE_ENTRY(jobject, Unsafe_GetReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
395 oop p = JNIHandles::resolve(obj);
396 assert_field_offset_sane(p, offset);
397 oop v = HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
398 return JNIHandles::make_local(THREAD, v);
399 } UNSAFE_END
400
401 UNSAFE_ENTRY(void, Unsafe_PutReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
402 oop x = JNIHandles::resolve(x_h);
403 oop p = JNIHandles::resolve(obj);
404 assert_field_offset_sane(p, offset);
405 HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
406 } UNSAFE_END
407
408 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) {
409 oop v = *(oop*) (address) addr;
410 return JNIHandles::make_local(THREAD, v);
411 } UNSAFE_END
412
413 #define DEFINE_GETSETOOP(java_type, Type) \
414 \
415 UNSAFE_ENTRY(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
416 return MemoryAccess<java_type>(thread, obj, offset).get(); \
417 } UNSAFE_END \
418 \
419 UNSAFE_ENTRY(void, Unsafe_Put##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
420 MemoryAccess<java_type>(thread, obj, offset).put(x); \
421 } UNSAFE_END \
422 \
423 // END DEFINE_GETSETOOP.
424
425 DEFINE_GETSETOOP(jboolean, Boolean)
426 DEFINE_GETSETOOP(jbyte, Byte)
427 DEFINE_GETSETOOP(jshort, Short);
428 DEFINE_GETSETOOP(jchar, Char);
429 DEFINE_GETSETOOP(jint, Int);
430 DEFINE_GETSETOOP(jlong, Long);
431 DEFINE_GETSETOOP(jfloat, Float);
432 DEFINE_GETSETOOP(jdouble, Double);
433
434 #undef DEFINE_GETSETOOP
435
436 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \
437 \
438 UNSAFE_ENTRY(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
439 return MemoryAccess<java_type>(thread, obj, offset).get_volatile(); \
440 } UNSAFE_END \
441 \
442 UNSAFE_ENTRY(void, Unsafe_Put##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
443 MemoryAccess<java_type>(thread, obj, offset).put_volatile(x); \
444 } UNSAFE_END \
445 \
446 // END DEFINE_GETSETOOP_VOLATILE.
447
448 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
449 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
450 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
451 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
452 DEFINE_GETSETOOP_VOLATILE(jint, Int);
453 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
454 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
455 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
456
457 #undef DEFINE_GETSETOOP_VOLATILE
458
459 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
460 OrderAccess::fence();
461 } UNSAFE_END
462
463 ////// Allocation requests
464
465 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
466 oop mirror = JNIHandles::resolve_non_null(cls);
467 InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(mirror));
468 if (k == vmClasses::Object_klass() && vmClasses::Object_klass()->is_abstract()) {
469 k = vmClasses::Identity_klass();
470 }
471 JvmtiVMObjectAllocEventCollector oam;
472 instanceOop i = InstanceKlass::allocate_instance(k->java_mirror(), CHECK_NULL);
473 return JNIHandles::make_local(THREAD, i);
474 } UNSAFE_END
475
476 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) {
477 size_t sz = (size_t)size;
478
479 assert(is_aligned(sz, HeapWordSize), "sz not aligned");
480
481 void* x = os::malloc(sz, mtOther);
482
483 return addr_to_java(x);
484 } UNSAFE_END
485
486 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) {
487 void* p = addr_from_java(addr);
488 size_t sz = (size_t)size;
489
490 assert(is_aligned(sz, HeapWordSize), "sz not aligned");
491
492 void* x = os::realloc(p, sz, mtOther);
493
494 return addr_to_java(x);
495 } UNSAFE_END
496
497 UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) {
498 void* p = addr_from_java(addr);
499
500 os::free(p);
501 } UNSAFE_END
502
503 UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) {
504 size_t sz = (size_t)size;
505
506 oop base = JNIHandles::resolve(obj);
507 void* p = index_oop_from_field_offset_long(base, offset);
508
509 Copy::fill_to_memory_atomic(p, sz, value);
510 } UNSAFE_END
511
512 UNSAFE_ENTRY(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) {
513 size_t sz = (size_t)size;
514
515 oop srcp = JNIHandles::resolve(srcObj);
516 oop dstp = JNIHandles::resolve(dstObj);
517
518 void* src = index_oop_from_field_offset_long(srcp, srcOffset);
519 void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
520 {
521 GuardUnsafeAccess guard(thread);
522 if (StubRoutines::unsafe_arraycopy() != NULL) {
523 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, thread));
524 StubRoutines::UnsafeArrayCopy_stub()(src, dst, sz);
525 } else {
526 Copy::conjoint_memory_atomic(src, dst, sz);
527 }
528 }
529 } UNSAFE_END
530
531 // This function is a leaf since if the source and destination are both in native memory
532 // the copy may potentially be very large, and we don't want to disable GC if we can avoid it.
533 // If either source or destination (or both) are on the heap, the function will enter VM using
534 // JVM_ENTRY_FROM_LEAF
535 UNSAFE_LEAF(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) {
536 size_t sz = (size_t)size;
537 size_t esz = (size_t)elemSize;
538
539 if (srcObj == NULL && dstObj == NULL) {
540 // Both src & dst are in native memory
541 address src = (address)srcOffset;
542 address dst = (address)dstOffset;
543
544 {
545 JavaThread* thread = JavaThread::thread_from_jni_environment(env);
546 GuardUnsafeAccess guard(thread);
547 Copy::conjoint_swap(src, dst, sz, esz);
548 }
549 } else {
550 // At least one of src/dst are on heap, transition to VM to access raw pointers
551
552 JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) {
553 oop srcp = JNIHandles::resolve(srcObj);
554 oop dstp = JNIHandles::resolve(dstObj);
555
556 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset);
557 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset);
558
559 {
560 GuardUnsafeAccess guard(thread);
561 Copy::conjoint_swap(src, dst, sz, esz);
562 }
563 } JVM_END
564 }
565 } UNSAFE_END
566
567 UNSAFE_LEAF (void, Unsafe_WriteBack0(JNIEnv *env, jobject unsafe, jlong line)) {
568 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
569 #ifdef ASSERT
570 if (TraceMemoryWriteback) {
571 tty->print_cr("Unsafe: writeback 0x%p", addr_from_java(line));
572 }
573 #endif
574
575 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, Thread::current()));
576 assert(StubRoutines::data_cache_writeback() != NULL, "sanity");
577 (StubRoutines::DataCacheWriteback_stub())(addr_from_java(line));
578 } UNSAFE_END
579
580 static void doWriteBackSync0(bool is_pre)
581 {
582 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, Thread::current()));
583 assert(StubRoutines::data_cache_writeback_sync() != NULL, "sanity");
584 (StubRoutines::DataCacheWritebackSync_stub())(is_pre);
585 }
586
587 UNSAFE_LEAF (void, Unsafe_WriteBackPreSync0(JNIEnv *env, jobject unsafe)) {
588 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
589 #ifdef ASSERT
590 if (TraceMemoryWriteback) {
591 tty->print_cr("Unsafe: writeback pre-sync");
592 }
593 #endif
594
595 doWriteBackSync0(true);
596 } UNSAFE_END
597
598 UNSAFE_LEAF (void, Unsafe_WriteBackPostSync0(JNIEnv *env, jobject unsafe)) {
599 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
600 #ifdef ASSERT
601 if (TraceMemoryWriteback) {
602 tty->print_cr("Unsafe: writeback pre-sync");
603 }
604 #endif
605
606 doWriteBackSync0(false);
607 } UNSAFE_END
608
609 ////// Random queries
610
611 static jlong find_field_offset(jclass clazz, jstring name, TRAPS) {
612 assert(clazz != NULL, "clazz must not be NULL");
613 assert(name != NULL, "name must not be NULL");
614
615 ResourceMark rm(THREAD);
616 char *utf_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
617
618 InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz)));
619
620 jint offset = -1;
621 for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
622 Symbol *name = fs.name();
623 if (name->equals(utf_name)) {
624 offset = fs.offset();
625 break;
626 }
627 }
628 if (offset < 0) {
629 THROW_0(vmSymbols::java_lang_InternalError());
630 }
631 return field_offset_from_byte_offset(offset);
632 }
633
634 static jlong find_field_offset(jobject field, int must_be_static, TRAPS) {
635 assert(field != NULL, "field must not be NULL");
636
637 oop reflected = JNIHandles::resolve_non_null(field);
638 oop mirror = java_lang_reflect_Field::clazz(reflected);
639 Klass* k = java_lang_Class::as_Klass(mirror);
640 int slot = java_lang_reflect_Field::slot(reflected);
641 int modifiers = java_lang_reflect_Field::modifiers(reflected);
642
643 if (must_be_static >= 0) {
644 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
645 if (must_be_static != really_is_static) {
646 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
647 }
648 }
649
650 int offset = InstanceKlass::cast(k)->field_offset(slot);
651 return field_offset_from_byte_offset(offset);
652 }
653
654 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
655 return find_field_offset(field, 0, THREAD);
656 } UNSAFE_END
657
658 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset1(JNIEnv *env, jobject unsafe, jclass c, jstring name)) {
659 return find_field_offset(c, name, THREAD);
660 } UNSAFE_END
661
662 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
663 return find_field_offset(field, 1, THREAD);
664 } UNSAFE_END
665
666 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) {
667 assert(field != NULL, "field must not be NULL");
668
669 // Note: In this VM implementation, a field address is always a short
670 // offset from the base of a a klass metaobject. Thus, the full dynamic
671 // range of the return type is never used. However, some implementations
672 // might put the static field inside an array shared by many classes,
673 // or even at a fixed address, in which case the address could be quite
674 // large. In that last case, this function would return NULL, since
675 // the address would operate alone, without any base pointer.
676
677 oop reflected = JNIHandles::resolve_non_null(field);
678 oop mirror = java_lang_reflect_Field::clazz(reflected);
679 int modifiers = java_lang_reflect_Field::modifiers(reflected);
680
681 if ((modifiers & JVM_ACC_STATIC) == 0) {
682 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
683 }
684
685 return JNIHandles::make_local(THREAD, mirror);
686 } UNSAFE_END
687
688 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
689 assert(clazz != NULL, "clazz must not be NULL");
690
691 oop mirror = JNIHandles::resolve_non_null(clazz);
692
693 Klass* klass = java_lang_Class::as_Klass(mirror);
694 if (klass != NULL && klass->should_be_initialized()) {
695 InstanceKlass* k = InstanceKlass::cast(klass);
696 k->initialize(CHECK);
697 }
698 }
699 UNSAFE_END
700
701 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
702 assert(clazz != NULL, "clazz must not be NULL");
703
704 oop mirror = JNIHandles::resolve_non_null(clazz);
705 Klass* klass = java_lang_Class::as_Klass(mirror);
706
707 if (klass != NULL && klass->should_be_initialized()) {
708 return true;
709 }
710
711 return false;
712 }
713 UNSAFE_END
714
715 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) {
716 assert(clazz != NULL, "clazz must not be NULL");
717
718 oop mirror = JNIHandles::resolve_non_null(clazz);
719 Klass* k = java_lang_Class::as_Klass(mirror);
720
721 if (k == NULL || !k->is_array_klass()) {
722 THROW(vmSymbols::java_lang_InvalidClassException());
723 } else if (k->is_objArray_klass()) {
724 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
725 scale = heapOopSize;
726 } else if (k->is_typeArray_klass()) {
727 TypeArrayKlass* tak = TypeArrayKlass::cast(k);
728 base = tak->array_header_in_bytes();
729 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
730 scale = (1 << tak->log2_element_size());
731 } else if (k->is_flatArray_klass()) {
732 FlatArrayKlass* vak = FlatArrayKlass::cast(k);
733 InlineKlass* vklass = vak->element_klass();
734 base = vak->array_header_in_bytes();
735 scale = vak->element_byte_size();
736 } else {
737 ShouldNotReachHere();
738 }
739 }
740
741 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) {
742 int base = 0, scale = 0;
743 getBaseAndScale(base, scale, clazz, CHECK_0);
744
745 return field_offset_from_byte_offset(base);
746 } UNSAFE_END
747
748
749 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) {
750 int base = 0, scale = 0;
751 getBaseAndScale(base, scale, clazz, CHECK_0);
752
753 // This VM packs both fields and array elements down to the byte.
754 // But watch out: If this changes, so that array references for
755 // a given primitive type (say, T_BOOLEAN) use different memory units
756 // than fields, this method MUST return zero for such arrays.
757 // For example, the VM used to store sub-word sized fields in full
758 // words in the object layout, so that accessors like getByte(Object,int)
759 // did not really do what one might expect for arrays. Therefore,
760 // this function used to report a zero scale factor, so that the user
761 // would know not to attempt to access sub-word array elements.
762 // // Code for unpacked fields:
763 // if (scale < wordSize) return 0;
764
765 // The following allows for a pretty general fieldOffset cookie scheme,
766 // but requires it to be linear in byte offset.
767 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
768 } UNSAFE_END
769
770
771 UNSAFE_ENTRY(jlong, Unsafe_GetObjectSize0(JNIEnv* env, jobject o, jobject obj))
772 oop p = JNIHandles::resolve(obj);
773 return p->size() * HeapWordSize;
774 UNSAFE_END
775
776
777 static inline void throw_new(JNIEnv *env, const char *ename) {
778 jclass cls = env->FindClass(ename);
779 if (env->ExceptionCheck()) {
780 env->ExceptionClear();
781 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", ename);
782 return;
783 }
784
785 env->ThrowNew(cls, NULL);
786 }
787
788 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
789 // Code lifted from JDK 1.3 ClassLoader.c
790
791 jbyte *body;
792 char *utfName = NULL;
793 jclass result = 0;
794 char buf[128];
795
796 assert(data != NULL, "Class bytes must not be NULL");
797 assert(length >= 0, "length must not be negative: %d", length);
798
799 if (UsePerfData) {
800 ClassLoader::unsafe_defineClassCallCounter()->inc();
801 }
802
803 body = NEW_C_HEAP_ARRAY_RETURN_NULL(jbyte, length, mtInternal);
804 if (body == NULL) {
805 throw_new(env, "java/lang/OutOfMemoryError");
806 return 0;
807 }
808
809 env->GetByteArrayRegion(data, offset, length, body);
810 if (env->ExceptionOccurred()) {
811 goto free_body;
812 }
813
814 if (name != NULL) {
815 uint len = env->GetStringUTFLength(name);
816 int unicode_len = env->GetStringLength(name);
817
818 if (len >= sizeof(buf)) {
819 utfName = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len + 1, mtInternal);
820 if (utfName == NULL) {
821 throw_new(env, "java/lang/OutOfMemoryError");
822 goto free_body;
823 }
824 } else {
825 utfName = buf;
826 }
827
828 env->GetStringUTFRegion(name, 0, unicode_len, utfName);
829
830 for (uint i = 0; i < len; i++) {
831 if (utfName[i] == '.') utfName[i] = '/';
832 }
833 }
834
835 result = JVM_DefineClass(env, utfName, loader, body, length, pd);
836
837 if (utfName && utfName != buf) {
838 FREE_C_HEAP_ARRAY(char, utfName);
839 }
840
841 free_body:
842 FREE_C_HEAP_ARRAY(jbyte, body);
843 return result;
844 }
845
846
847 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) {
848 ThreadToNativeFromVM ttnfv(thread);
849
850 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
851 } UNSAFE_END
852
853
854 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
855 ThreadToNativeFromVM ttnfv(thread);
856 env->Throw(thr);
857 } UNSAFE_END
858
859 // JSR166 ------------------------------------------------------------------
860
861 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
862 oop x = JNIHandles::resolve(x_h);
863 oop e = JNIHandles::resolve(e_h);
864 oop p = JNIHandles::resolve(obj);
865 assert_field_offset_sane(p, offset);
866 oop res = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x);
867 return JNIHandles::make_local(THREAD, res);
868 } UNSAFE_END
869
870 UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
871 oop p = JNIHandles::resolve(obj);
872 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
873 return Atomic::cmpxchg(addr, e, x);
874 } UNSAFE_END
875
876 UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
877 oop p = JNIHandles::resolve(obj);
878 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
879 return Atomic::cmpxchg(addr, e, x);
880 } UNSAFE_END
881
882 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
883 oop x = JNIHandles::resolve(x_h);
884 oop e = JNIHandles::resolve(e_h);
885 oop p = JNIHandles::resolve(obj);
886 assert_field_offset_sane(p, offset);
887 oop ret = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x);
888 return ret == e;
889 } UNSAFE_END
890
891 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
892 oop p = JNIHandles::resolve(obj);
893 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
894 return Atomic::cmpxchg(addr, e, x) == e;
895 } UNSAFE_END
896
897 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
898 oop p = JNIHandles::resolve(obj);
899 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
900 return Atomic::cmpxchg(addr, e, x) == e;
901 } UNSAFE_END
902
903 static void post_thread_park_event(EventThreadPark* event, const oop obj, jlong timeout_nanos, jlong until_epoch_millis) {
904 assert(event != NULL, "invariant");
905 assert(event->should_commit(), "invariant");
906 event->set_parkedClass((obj != NULL) ? obj->klass() : NULL);
907 event->set_timeout(timeout_nanos);
908 event->set_until(until_epoch_millis);
909 event->set_address((obj != NULL) ? (u8)cast_from_oop<uintptr_t>(obj) : 0);
910 event->commit();
911 }
912
913 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
914 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
915 EventThreadPark event;
916
917 JavaThreadParkedState jtps(thread, time != 0);
918 thread->parker()->park(isAbsolute != 0, time);
919 if (event.should_commit()) {
920 const oop obj = thread->current_park_blocker();
921 if (time == 0) {
922 post_thread_park_event(&event, obj, min_jlong, min_jlong);
923 } else {
924 if (isAbsolute != 0) {
925 post_thread_park_event(&event, obj, min_jlong, time);
926 } else {
927 post_thread_park_event(&event, obj, time, min_jlong);
928 }
929 }
930 }
931 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
932 } UNSAFE_END
933
934 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
935 if (jthread != NULL) {
936 ThreadsListHandle tlh;
937 JavaThread* thr = NULL;
938 oop java_thread = NULL;
939 (void) tlh.cv_internal_thread_to_JavaThread(jthread, &thr, &java_thread);
940 if (java_thread != NULL) {
941 // This is a valid oop.
942 if (thr != NULL) {
943 // The JavaThread is alive.
944 Parker* p = thr->parker();
945 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
946 p->unpark();
947 }
948 }
949 } // ThreadsListHandle is destroyed here.
950
951 } UNSAFE_END
952
953 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
954 const int max_nelem = 3;
955 double la[max_nelem];
956 jint ret;
957
958 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
959 assert(a->is_typeArray(), "must be type array");
960
961 ret = os::loadavg(la, nelem);
962 if (ret == -1) {
963 return -1;
964 }
965
966 // if successful, ret is the number of samples actually retrieved.
967 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
968 switch(ret) {
969 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
970 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
971 case 1: a->double_at_put(0, (jdouble)la[0]); break;
972 }
973
974 return ret;
975 } UNSAFE_END
976
977
978 /// JVM_RegisterUnsafeMethods
979
980 #define ADR "J"
981
982 #define LANG "Ljava/lang/"
983
984 #define OBJ LANG "Object;"
985 #define CLS LANG "Class;"
986 #define FLD LANG "reflect/Field;"
987 #define THR LANG "Throwable;"
988
989 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
990 #define DAC_Args CLS "[B[" OBJ
991
992 #define CC (char*) /*cast a literal from (const char*)*/
993 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
994
995 #define DECLARE_GETPUTOOP(Type, Desc) \
996 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
997 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \
998 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
999 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)}
1000
1001
1002 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1003 {CC "getReference", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetReference)},
1004 {CC "putReference", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReference)},
1005 {CC "getReferenceVolatile", CC "(" OBJ "J)" OBJ, FN_PTR(Unsafe_GetReferenceVolatile)},
1006 {CC "putReferenceVolatile", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReferenceVolatile)},
1007
1008 {CC "isFlattenedArray", CC "(" CLS ")Z", FN_PTR(Unsafe_IsFlattenedArray)},
1009 {CC "isFlattenedField0", CC "(" OBJ ")Z", FN_PTR(Unsafe_IsFlattenedField)},
1010 {CC "getValue", CC "(" OBJ "J" CLS ")" OBJ, FN_PTR(Unsafe_GetValue)},
1011 {CC "putValue", CC "(" OBJ "J" CLS OBJ ")V", FN_PTR(Unsafe_PutValue)},
1012 {CC "uninitializedDefaultValue", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_UninitializedDefaultValue)},
1013 {CC "makePrivateBuffer", CC "(" OBJ ")" OBJ, FN_PTR(Unsafe_MakePrivateBuffer)},
1014 {CC "finishPrivateBuffer", CC "(" OBJ ")" OBJ, FN_PTR(Unsafe_FinishPrivateBuffer)},
1015 {CC "valueHeaderSize", CC "(" CLS ")J", FN_PTR(Unsafe_ValueHeaderSize)},
1016
1017 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1018
1019 DECLARE_GETPUTOOP(Boolean, Z),
1020 DECLARE_GETPUTOOP(Byte, B),
1021 DECLARE_GETPUTOOP(Short, S),
1022 DECLARE_GETPUTOOP(Char, C),
1023 DECLARE_GETPUTOOP(Int, I),
1024 DECLARE_GETPUTOOP(Long, J),
1025 DECLARE_GETPUTOOP(Float, F),
1026 DECLARE_GETPUTOOP(Double, D),
1027
1028 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1029 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1030 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1031
1032 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1033 {CC "objectFieldOffset1", CC "(" CLS LANG "String;)J", FN_PTR(Unsafe_ObjectFieldOffset1)},
1034 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1035 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1036 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1037 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1038 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1039 {CC "getObjectSize0", CC "(Ljava/lang/Object;)J", FN_PTR(Unsafe_GetObjectSize0)},
1040
1041 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1042 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1043 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1044 {CC "compareAndSetReference",CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSetReference)},
1045 {CC "compareAndSetInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSetInt)},
1046 {CC "compareAndSetLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSetLong)},
1047 {CC "compareAndExchangeReference", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeReference)},
1048 {CC "compareAndExchangeInt", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)},
1049 {CC "compareAndExchangeLong", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)},
1050
1051 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1052 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1053
1054 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1055
1056 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1057 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1058 {CC "writeback0", CC "(" "J" ")V", FN_PTR(Unsafe_WriteBack0)},
1059 {CC "writebackPreSync0", CC "()V", FN_PTR(Unsafe_WriteBackPreSync0)},
1060 {CC "writebackPostSync0", CC "()V", FN_PTR(Unsafe_WriteBackPostSync0)},
1061 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1062
1063 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1064
1065 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1066 };
1067
1068 #undef CC
1069 #undef FN_PTR
1070
1071 #undef ADR
1072 #undef LANG
1073 #undef OBJ
1074 #undef CLS
1075 #undef FLD
1076 #undef THR
1077 #undef DC_Args
1078 #undef DAC_Args
1079
1080 #undef DECLARE_GETPUTOOP
1081
1082
1083 // This function is exported, used by NativeLookup.
1084 // The Unsafe_xxx functions above are called only from the interpreter.
1085 // The optimizer looks at names and signatures to recognize
1086 // individual functions.
1087
1088 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1089 ThreadToNativeFromVM ttnfv(thread);
1090
1091 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1092 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1093 } JVM_END