1 /*
2 * Copyright (c) 2000, 2024, 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 "classfile/classFileStream.hpp"
27 #include "classfile/classLoader.hpp"
28 #include "classfile/classLoadInfo.hpp"
29 #include "classfile/javaClasses.inline.hpp"
30 #include "classfile/systemDictionary.hpp"
31 #include "classfile/vmSymbols.hpp"
32 #include "jfr/jfrEvents.hpp"
33 #include "jni.h"
34 #include "jvm.h"
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/javaThread.inline.hpp"
56 #include "runtime/jniHandles.inline.hpp"
57 #include "runtime/orderAccess.hpp"
58 #include "runtime/reflection.hpp"
59 #include "runtime/sharedRuntime.hpp"
60 #include "runtime/stubRoutines.hpp"
61 #include "runtime/threadSMR.hpp"
62 #include "runtime/vmOperations.hpp"
63 #include "runtime/vm_version.hpp"
64 #include "sanitizers/ub.hpp"
65 #include "services/threadService.hpp"
66 #include "utilities/align.hpp"
67 #include "utilities/copy.hpp"
68 #include "utilities/dtrace.hpp"
69 #include "utilities/macros.hpp"
70
71 /**
72 * Implementation of the jdk.internal.misc.Unsafe class
73 */
74
75
76 #define MAX_OBJECT_SIZE \
77 ( arrayOopDesc::base_offset_in_bytes(T_DOUBLE) \
78 + ((julong)max_jint * sizeof(double)) )
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 // All memory access methods (e.g. getInt, copyMemory) must use this macro.
87 // We call these methods "scoped" methods, as access to these methods is
88 // typically governed by a "scope" (a MemorySessionImpl object), and no
89 // access is allowed when the scope is no longer alive.
90 //
91 // Closing a scope object (cf. scopedMemoryAccess.cpp) can install
92 // an async exception during a safepoint. When that happens,
93 // scoped methods are not allowed to touch the underlying memory (as that
94 // memory might have been released). Therefore, when entering a scoped method
95 // we check if an async exception has been installed, and return immediately
96 // if that is the case.
97 //
98 // As a rule, we disallow safepoints in the middle of a scoped method.
99 // If an async exception handshake were installed in such a safepoint,
100 // memory access might still occur before the handshake is honored by
101 // the accessing thread.
102 //
103 // Corollary: as threads in native state are considered to be at a safepoint,
104 // scoped methods must NOT be executed while in the native thread state.
105 // Because of this, there can be no UNSAFE_LEAF_SCOPED.
106 #define UNSAFE_ENTRY_SCOPED(result_type, header) \
107 JVM_ENTRY(static result_type, header) \
108 if (thread->has_async_exception_condition()) {return (result_type)0;}
109
110 #define UNSAFE_END JVM_END
111
112
113 static inline void* addr_from_java(jlong addr) {
114 // This assert fails in a variety of ways on 32-bit systems.
115 // It is impossible to predict whether native code that converts
116 // pointers to longs will sign-extend or zero-extend the addresses.
117 //assert(addr == (uintptr_t)addr, "must not be odd high bits");
118 return (void*)(uintptr_t)addr;
119 }
120
121 static inline jlong addr_to_java(void* p) {
122 assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
123 return (uintptr_t)p;
124 }
125
126
127 // Note: The VM's obj_field and related accessors use byte-scaled
128 // ("unscaled") offsets, just as the unsafe methods do.
129
130 // However, the method Unsafe.fieldOffset explicitly declines to
131 // guarantee this. The field offset values manipulated by the Java user
132 // through the Unsafe API are opaque cookies that just happen to be byte
133 // offsets. We represent this state of affairs by passing the cookies
134 // through conversion functions when going between the VM and the Unsafe API.
135 // The conversion functions just happen to be no-ops at present.
136
137 static inline jlong field_offset_to_byte_offset(jlong field_offset) {
138 return field_offset;
139 }
140
141 static inline int field_offset_from_byte_offset(int byte_offset) {
142 return byte_offset;
143 }
144
145 static inline void assert_field_offset_sane(oop p, jlong field_offset) {
146 #ifdef ASSERT
147 jlong byte_offset = field_offset_to_byte_offset(field_offset);
148
149 if (p != nullptr) {
150 assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
151 if (byte_offset == (jint)byte_offset) {
152 void* ptr_plus_disp = cast_from_oop<address>(p) + byte_offset;
153 assert(p->field_addr<void>((jint)byte_offset) == ptr_plus_disp,
154 "raw [ptr+disp] must be consistent with oop::field_addr");
155 }
156 jlong p_size = HeapWordSize * (jlong)(p->size());
157 assert(byte_offset < p_size, "Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, (int64_t)byte_offset, (int64_t)p_size);
158 }
159 #endif
160 }
161
162 static inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
163 assert_field_offset_sane(p, field_offset);
164 uintptr_t base_address = cast_from_oop<uintptr_t>(p);
165 uintptr_t byte_offset = (uintptr_t)field_offset_to_byte_offset(field_offset);
166 return (void*)(base_address + byte_offset);
167 }
168
169 // Externally callable versions:
170 // (Use these in compiler intrinsics which emulate unsafe primitives.)
171 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
172 return field_offset;
173 }
174 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
175 return byte_offset;
176 }
177
178 ///// Data read/writes on the Java heap and in native (off-heap) memory
179
180 /**
181 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access()
182 */
183 class GuardUnsafeAccess {
184 JavaThread* _thread;
185
186 public:
187 GuardUnsafeAccess(JavaThread* thread) : _thread(thread) {
188 // native/off-heap access which may raise SIGBUS if accessing
189 // memory mapped file data in a region of the file which has
190 // been truncated and is now invalid.
191 _thread->set_doing_unsafe_access(true);
192 }
193
194 ~GuardUnsafeAccess() {
195 _thread->set_doing_unsafe_access(false);
196 }
197 };
198
199 /**
200 * Helper class for accessing memory.
201 *
202 * Normalizes values and wraps accesses in
203 * JavaThread::doing_unsafe_access() if needed.
204 */
205 template <typename T>
206 class MemoryAccess : StackObj {
207 JavaThread* _thread;
208 oop _obj;
209 ptrdiff_t _offset;
210
211 // Resolves and returns the address of the memory access.
212 // This raw memory access may fault, so we make sure it happens within the
213 // guarded scope by making the access volatile at least. Since the store
214 // of Thread::set_doing_unsafe_access() is also volatile, these accesses
215 // can not be reordered by the compiler. Therefore, if the access triggers
216 // a fault, we will know that Thread::doing_unsafe_access() returns true.
217 volatile T* addr() {
218 void* addr = index_oop_from_field_offset_long(_obj, _offset);
219 return static_cast<volatile T*>(addr);
220 }
221
222 template <typename U>
223 U normalize_for_write(U x) {
224 return x;
225 }
226
227 jboolean normalize_for_write(jboolean x) {
228 return x & 1;
229 }
230
231 template <typename U>
232 U normalize_for_read(U x) {
233 return x;
234 }
235
236 jboolean normalize_for_read(jboolean x) {
237 return x != 0;
238 }
239
240 public:
241 MemoryAccess(JavaThread* thread, jobject obj, jlong offset)
242 : _thread(thread), _obj(JNIHandles::resolve(obj)), _offset((ptrdiff_t)offset) {
243 assert_field_offset_sane(_obj, offset);
244 }
245
246 T get() {
247 GuardUnsafeAccess guard(_thread);
248 return normalize_for_read(*addr());
249 }
250
251 // we use this method at some places for writing to 0 e.g. to cause a crash;
252 // ubsan does not know that this is the desired behavior
253 ATTRIBUTE_NO_UBSAN
254 void put(T x) {
255 GuardUnsafeAccess guard(_thread);
256 assert(_obj == nullptr || !_obj->is_inline_type() || _obj->mark().is_larval_state(), "must be an object instance or a larval inline type");
257 *addr() = normalize_for_write(x);
258 }
259
260 T get_volatile() {
261 GuardUnsafeAccess guard(_thread);
262 volatile T ret = RawAccess<MO_SEQ_CST>::load(addr());
263 return normalize_for_read(ret);
264 }
265
266 void put_volatile(T x) {
267 GuardUnsafeAccess guard(_thread);
268 RawAccess<MO_SEQ_CST>::store(addr(), normalize_for_write(x));
269 }
270 };
271
272 #ifdef ASSERT
273 /*
274 * Get the field descriptor of the field of the given object at the given offset.
275 */
276 static bool get_field_descriptor(oop p, jlong offset, fieldDescriptor* fd) {
277 bool found = false;
278 Klass* k = p->klass();
279 if (k->is_instance_klass()) {
280 InstanceKlass* ik = InstanceKlass::cast(k);
281 found = ik->find_field_from_offset((int)offset, false, fd);
282 if (!found && ik->is_mirror_instance_klass()) {
283 Klass* k2 = java_lang_Class::as_Klass(p);
284 if (k2->is_instance_klass()) {
285 ik = InstanceKlass::cast(k2);
286 found = ik->find_field_from_offset((int)offset, true, fd);
287 }
288 }
289 }
290 return found;
291 }
292 #endif // ASSERT
293
294 static void assert_and_log_unsafe_value_access(oop p, jlong offset, InlineKlass* vk) {
295 Klass* k = p->klass();
296 #ifdef ASSERT
297 if (k->is_instance_klass()) {
298 assert_field_offset_sane(p, offset);
299 fieldDescriptor fd;
300 bool found = get_field_descriptor(p, offset, &fd);
301 if (found) {
302 assert(found, "value field not found");
303 assert(fd.is_flat(), "field not flat");
304 } else {
305 if (log_is_enabled(Trace, valuetypes)) {
306 log_trace(valuetypes)("not a field in %s at offset " UINT64_FORMAT_X,
307 p->klass()->external_name(), (uint64_t)offset);
308 }
309 }
310 } else if (k->is_flatArray_klass()) {
311 FlatArrayKlass* vak = FlatArrayKlass::cast(k);
312 int index = (offset - vak->array_header_in_bytes()) / vak->element_byte_size();
313 address dest = (address)((flatArrayOop)p)->value_at_addr(index, vak->layout_helper());
314 assert(dest == (cast_from_oop<address>(p) + offset), "invalid offset");
315 } else {
316 ShouldNotReachHere();
317 }
318 #endif // ASSERT
319 if (log_is_enabled(Trace, valuetypes)) {
320 if (k->is_flatArray_klass()) {
321 FlatArrayKlass* vak = FlatArrayKlass::cast(k);
322 int index = (offset - vak->array_header_in_bytes()) / vak->element_byte_size();
323 address dest = (address)((flatArrayOop)p)->value_at_addr(index, vak->layout_helper());
324 log_trace(valuetypes)("%s array type %s index %d element size %d offset " UINT64_FORMAT_X " at " INTPTR_FORMAT,
325 p->klass()->external_name(), vak->external_name(),
326 index, vak->element_byte_size(), (uint64_t)offset, p2i(dest));
327 } else {
328 log_trace(valuetypes)("%s field type %s at offset " UINT64_FORMAT_X,
329 p->klass()->external_name(), vk->external_name(), (uint64_t)offset);
330 }
331 }
332 }
333
334 // These functions allow a null base pointer with an arbitrary address.
335 // But if the base pointer is non-null, the offset should make some sense.
336 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
337 UNSAFE_ENTRY(jobject, Unsafe_GetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
338 oop p = JNIHandles::resolve(obj);
339 assert_field_offset_sane(p, offset);
340 oop v = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
341 return JNIHandles::make_local(THREAD, v);
342 } UNSAFE_END
343
344 UNSAFE_ENTRY(void, Unsafe_PutReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
345 oop x = JNIHandles::resolve(x_h);
346 oop p = JNIHandles::resolve(obj);
347 assert_field_offset_sane(p, offset);
348 assert(!p->is_inline_type() || p->mark().is_larval_state(), "must be an object instance or a larval inline type");
349 HeapAccess<ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
350 } UNSAFE_END
351
352 UNSAFE_ENTRY(jlong, Unsafe_ValueHeaderSize(JNIEnv *env, jobject unsafe, jclass c)) {
353 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(c));
354 InlineKlass* vk = InlineKlass::cast(k);
355 return vk->first_field_offset();
356 } UNSAFE_END
357
358 UNSAFE_ENTRY(jboolean, Unsafe_IsFlatField(JNIEnv *env, jobject unsafe, jobject o)) {
359 oop f = JNIHandles::resolve_non_null(o);
360 Klass* k = java_lang_Class::as_Klass(java_lang_reflect_Field::clazz(f));
361 int slot = java_lang_reflect_Field::slot(f);
362 return InstanceKlass::cast(k)->field_is_flat(slot);
363 } UNSAFE_END
364
365 UNSAFE_ENTRY(jboolean, Unsafe_HasNullMarker(JNIEnv *env, jobject unsafe, jobject o)) {
366 oop f = JNIHandles::resolve_non_null(o);
367 Klass* k = java_lang_Class::as_Klass(java_lang_reflect_Field::clazz(f));
368 int slot = java_lang_reflect_Field::slot(f);
369 return InstanceKlass::cast(k)->field_has_null_marker(slot);
370 } UNSAFE_END
371
372 UNSAFE_ENTRY(jint, Unsafe_NullMarkerOffset(JNIEnv *env, jobject unsafe, jobject o)) {
373 oop f = JNIHandles::resolve_non_null(o);
374 Klass* k = java_lang_Class::as_Klass(java_lang_reflect_Field::clazz(f));
375 int slot = java_lang_reflect_Field::slot(f);
376 return InstanceKlass::cast(k)->null_marker_offset(slot);
377 } UNSAFE_END
378
379 UNSAFE_ENTRY(jboolean, Unsafe_IsFlatArray(JNIEnv *env, jobject unsafe, jclass c)) {
380 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(c));
381 return k->is_flatArray_klass();
382 } UNSAFE_END
383
384 UNSAFE_ENTRY(jobject, Unsafe_UninitializedDefaultValue(JNIEnv *env, jobject unsafe, jclass vc)) {
385 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(vc));
386 InlineKlass* vk = InlineKlass::cast(k);
387 oop v = vk->default_value();
388 return JNIHandles::make_local(THREAD, v);
389 } UNSAFE_END
390
391 UNSAFE_ENTRY(jobject, Unsafe_GetValue(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jclass vc)) {
392 oop base = JNIHandles::resolve(obj);
393 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(vc));
394 InlineKlass* vk = InlineKlass::cast(k);
395 assert_and_log_unsafe_value_access(base, offset, vk);
396 Handle base_h(THREAD, base);
397 oop v = vk->read_flat_field(base_h(), offset, LayoutKind::PAYLOAD, CHECK_NULL); // TODO FIXME Hard coded layout kind to make the code compile, Unsafe must be upgraded to handle correct layout kind
398 return JNIHandles::make_local(THREAD, v);
399 } UNSAFE_END
400
401 UNSAFE_ENTRY(void, Unsafe_PutValue(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jclass vc, jobject value)) {
402 oop base = JNIHandles::resolve(obj);
403 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(vc));
404 InlineKlass* vk = InlineKlass::cast(k);
405 assert(!base->is_inline_type() || base->mark().is_larval_state(), "must be an object instance or a larval inline type");
406 assert_and_log_unsafe_value_access(base, offset, vk);
407 oop v = JNIHandles::resolve(value);
408 vk->write_flat_field(base, offset, v, true /*null free*/, LayoutKind::PAYLOAD, CHECK); // TODO FIXME Hard coded layout kind to make the code compile, Unsafe must be upgraded to handle correct layout kind
409 } UNSAFE_END
410
411 UNSAFE_ENTRY(jobject, Unsafe_MakePrivateBuffer(JNIEnv *env, jobject unsafe, jobject value)) {
412 oop v = JNIHandles::resolve_non_null(value);
413 assert(v->is_inline_type(), "must be an inline type instance");
414 Handle vh(THREAD, v);
415 InlineKlass* vk = InlineKlass::cast(v->klass());
416 instanceOop new_value = vk->allocate_instance_buffer(CHECK_NULL);
417 vk->inline_copy_oop_to_new_oop(vh(), new_value, LayoutKind::PAYLOAD); // FIXME temporary hack for the transition
418 markWord mark = new_value->mark();
419 new_value->set_mark(mark.enter_larval_state());
420 return JNIHandles::make_local(THREAD, new_value);
421 } UNSAFE_END
422
423 UNSAFE_ENTRY(jobject, Unsafe_FinishPrivateBuffer(JNIEnv *env, jobject unsafe, jobject value)) {
424 oop v = JNIHandles::resolve(value);
425 assert(v->mark().is_larval_state(), "must be a larval value");
426 markWord mark = v->mark();
427 v->set_mark(mark.exit_larval_state());
428 return JNIHandles::make_local(THREAD, v);
429 } UNSAFE_END
430
431 UNSAFE_ENTRY(jobject, Unsafe_GetReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
432 oop p = JNIHandles::resolve(obj);
433 assert_field_offset_sane(p, offset);
434 oop v = HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
435 return JNIHandles::make_local(THREAD, v);
436 } UNSAFE_END
437
438 UNSAFE_ENTRY(void, Unsafe_PutReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
439 oop x = JNIHandles::resolve(x_h);
440 oop p = JNIHandles::resolve(obj);
441 assert_field_offset_sane(p, offset);
442 HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
443 } UNSAFE_END
444
445 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) {
446 oop v = *(oop*) (address) addr;
447 return JNIHandles::make_local(THREAD, v);
448 } UNSAFE_END
449
450 #define DEFINE_GETSETOOP(java_type, Type) \
451 \
452 UNSAFE_ENTRY_SCOPED(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
453 return MemoryAccess<java_type>(thread, obj, offset).get(); \
454 } UNSAFE_END \
455 \
456 UNSAFE_ENTRY_SCOPED(void, Unsafe_Put##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
457 MemoryAccess<java_type>(thread, obj, offset).put(x); \
458 } UNSAFE_END \
459 \
460 // END DEFINE_GETSETOOP.
461
462 DEFINE_GETSETOOP(jboolean, Boolean)
463 DEFINE_GETSETOOP(jbyte, Byte)
464 DEFINE_GETSETOOP(jshort, Short);
465 DEFINE_GETSETOOP(jchar, Char);
466 DEFINE_GETSETOOP(jint, Int);
467 DEFINE_GETSETOOP(jlong, Long);
468 DEFINE_GETSETOOP(jfloat, Float);
469 DEFINE_GETSETOOP(jdouble, Double);
470
471 #undef DEFINE_GETSETOOP
472
473 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \
474 \
475 UNSAFE_ENTRY_SCOPED(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
476 return MemoryAccess<java_type>(thread, obj, offset).get_volatile(); \
477 } UNSAFE_END \
478 \
479 UNSAFE_ENTRY_SCOPED(void, Unsafe_Put##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
480 MemoryAccess<java_type>(thread, obj, offset).put_volatile(x); \
481 } UNSAFE_END \
482 \
483 // END DEFINE_GETSETOOP_VOLATILE.
484
485 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
486 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
487 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
488 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
489 DEFINE_GETSETOOP_VOLATILE(jint, Int);
490 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
491 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
492 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
493
494 #undef DEFINE_GETSETOOP_VOLATILE
495
496 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
497 OrderAccess::fence();
498 } UNSAFE_END
499
500 ////// Allocation requests
501
502 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
503 JvmtiVMObjectAllocEventCollector oam;
504 instanceOop i = InstanceKlass::allocate_instance(JNIHandles::resolve_non_null(cls), CHECK_NULL);
505 return JNIHandles::make_local(THREAD, i);
506 } UNSAFE_END
507
508 UNSAFE_LEAF(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) {
509 size_t sz = (size_t)size;
510
511 assert(is_aligned(sz, HeapWordSize), "sz not aligned");
512
513 void* x = os::malloc(sz, mtOther);
514
515 return addr_to_java(x);
516 } UNSAFE_END
517
518 UNSAFE_LEAF(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) {
519 void* p = addr_from_java(addr);
520 size_t sz = (size_t)size;
521
522 assert(is_aligned(sz, HeapWordSize), "sz not aligned");
523
524 void* x = os::realloc(p, sz, mtOther);
525
526 return addr_to_java(x);
527 } UNSAFE_END
528
529 UNSAFE_LEAF(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) {
530 void* p = addr_from_java(addr);
531
532 os::free(p);
533 } UNSAFE_END
534
535 UNSAFE_ENTRY_SCOPED(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) {
536 size_t sz = (size_t)size;
537
538 oop base = JNIHandles::resolve(obj);
539 void* p = index_oop_from_field_offset_long(base, offset);
540
541 {
542 GuardUnsafeAccess guard(thread);
543 if (StubRoutines::unsafe_setmemory() != nullptr) {
544 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, thread));
545 StubRoutines::UnsafeSetMemory_stub()(p, sz, value);
546 } else {
547 Copy::fill_to_memory_atomic(p, sz, value);
548 }
549 }
550 } UNSAFE_END
551
552 UNSAFE_ENTRY_SCOPED(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) {
553 size_t sz = (size_t)size;
554
555 oop srcp = JNIHandles::resolve(srcObj);
556 oop dstp = JNIHandles::resolve(dstObj);
557
558 void* src = index_oop_from_field_offset_long(srcp, srcOffset);
559 void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
560 {
561 GuardUnsafeAccess guard(thread);
562 if (StubRoutines::unsafe_arraycopy() != nullptr) {
563 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, thread));
564 StubRoutines::UnsafeArrayCopy_stub()(src, dst, sz);
565 } else {
566 Copy::conjoint_memory_atomic(src, dst, sz);
567 }
568 }
569 } UNSAFE_END
570
571 UNSAFE_ENTRY_SCOPED(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) {
572 size_t sz = (size_t)size;
573 size_t esz = (size_t)elemSize;
574
575 oop srcp = JNIHandles::resolve(srcObj);
576 oop dstp = JNIHandles::resolve(dstObj);
577
578 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset);
579 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset);
580
581 {
582 GuardUnsafeAccess guard(thread);
583 Copy::conjoint_swap(src, dst, sz, esz);
584 }
585 } UNSAFE_END
586
587 UNSAFE_LEAF (void, Unsafe_WriteBack0(JNIEnv *env, jobject unsafe, jlong line)) {
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 0x%p", addr_from_java(line));
592 }
593 #endif
594
595 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, Thread::current()));
596 assert(StubRoutines::data_cache_writeback() != nullptr, "sanity");
597 (StubRoutines::DataCacheWriteback_stub())(addr_from_java(line));
598 } UNSAFE_END
599
600 static void doWriteBackSync0(bool is_pre)
601 {
602 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, Thread::current()));
603 assert(StubRoutines::data_cache_writeback_sync() != nullptr, "sanity");
604 (StubRoutines::DataCacheWritebackSync_stub())(is_pre);
605 }
606
607 UNSAFE_LEAF (void, Unsafe_WriteBackPreSync0(JNIEnv *env, jobject unsafe)) {
608 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
609 #ifdef ASSERT
610 if (TraceMemoryWriteback) {
611 tty->print_cr("Unsafe: writeback pre-sync");
612 }
613 #endif
614
615 doWriteBackSync0(true);
616 } UNSAFE_END
617
618 UNSAFE_LEAF (void, Unsafe_WriteBackPostSync0(JNIEnv *env, jobject unsafe)) {
619 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
620 #ifdef ASSERT
621 if (TraceMemoryWriteback) {
622 tty->print_cr("Unsafe: writeback pre-sync");
623 }
624 #endif
625
626 doWriteBackSync0(false);
627 } UNSAFE_END
628
629 ////// Random queries
630
631 static jlong find_field_offset(jclass clazz, jstring name, TRAPS) {
632 assert(clazz != nullptr, "clazz must not be null");
633 assert(name != nullptr, "name must not be null");
634
635 ResourceMark rm(THREAD);
636 char *utf_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
637
638 InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz)));
639
640 jint offset = -1;
641 for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
642 Symbol *name = fs.name();
643 if (name->equals(utf_name)) {
644 offset = fs.offset();
645 break;
646 }
647 }
648 if (offset < 0) {
649 THROW_0(vmSymbols::java_lang_InternalError());
650 }
651 return field_offset_from_byte_offset(offset);
652 }
653
654 static jlong find_field_offset(jobject field, int must_be_static, TRAPS) {
655 assert(field != nullptr, "field must not be null");
656
657 oop reflected = JNIHandles::resolve_non_null(field);
658 oop mirror = java_lang_reflect_Field::clazz(reflected);
659 Klass* k = java_lang_Class::as_Klass(mirror);
660 int slot = java_lang_reflect_Field::slot(reflected);
661 int modifiers = java_lang_reflect_Field::modifiers(reflected);
662
663 if (must_be_static >= 0) {
664 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
665 if (must_be_static != really_is_static) {
666 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
667 }
668 }
669
670 int offset = InstanceKlass::cast(k)->field_offset(slot);
671 return field_offset_from_byte_offset(offset);
672 }
673
674 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
675 return find_field_offset(field, 0, THREAD);
676 } UNSAFE_END
677
678 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset1(JNIEnv *env, jobject unsafe, jclass c, jstring name)) {
679 return find_field_offset(c, name, THREAD);
680 } UNSAFE_END
681
682 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
683 return find_field_offset(field, 1, THREAD);
684 } UNSAFE_END
685
686 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) {
687 assert(field != nullptr, "field must not be null");
688
689 // Note: In this VM implementation, a field address is always a short
690 // offset from the base of a klass metaobject. Thus, the full dynamic
691 // range of the return type is never used. However, some implementations
692 // might put the static field inside an array shared by many classes,
693 // or even at a fixed address, in which case the address could be quite
694 // large. In that last case, this function would return null, since
695 // the address would operate alone, without any base pointer.
696
697 oop reflected = JNIHandles::resolve_non_null(field);
698 oop mirror = java_lang_reflect_Field::clazz(reflected);
699 int modifiers = java_lang_reflect_Field::modifiers(reflected);
700
701 if ((modifiers & JVM_ACC_STATIC) == 0) {
702 THROW_NULL(vmSymbols::java_lang_IllegalArgumentException());
703 }
704
705 return JNIHandles::make_local(THREAD, mirror);
706 } UNSAFE_END
707
708 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
709 assert(clazz != nullptr, "clazz must not be null");
710
711 oop mirror = JNIHandles::resolve_non_null(clazz);
712
713 Klass* klass = java_lang_Class::as_Klass(mirror);
714 if (klass != nullptr && klass->should_be_initialized()) {
715 InstanceKlass* k = InstanceKlass::cast(klass);
716 k->initialize(CHECK);
717 }
718 }
719 UNSAFE_END
720
721 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
722 assert(clazz != nullptr, "clazz must not be null");
723
724 oop mirror = JNIHandles::resolve_non_null(clazz);
725 Klass* klass = java_lang_Class::as_Klass(mirror);
726
727 if (klass != nullptr && klass->should_be_initialized()) {
728 return true;
729 }
730
731 return false;
732 }
733 UNSAFE_END
734
735 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) {
736 assert(clazz != nullptr, "clazz must not be null");
737
738 oop mirror = JNIHandles::resolve_non_null(clazz);
739 Klass* k = java_lang_Class::as_Klass(mirror);
740
741 if (k == nullptr || !k->is_array_klass()) {
742 THROW(vmSymbols::java_lang_InvalidClassException());
743 } else if (k->is_objArray_klass()) {
744 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
745 scale = heapOopSize;
746 } else if (k->is_typeArray_klass()) {
747 TypeArrayKlass* tak = TypeArrayKlass::cast(k);
748 base = tak->array_header_in_bytes();
749 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
750 scale = (1 << tak->log2_element_size());
751 } else if (k->is_flatArray_klass()) {
752 FlatArrayKlass* vak = FlatArrayKlass::cast(k);
753 InlineKlass* vklass = vak->element_klass();
754 base = vak->array_header_in_bytes();
755 scale = vak->element_byte_size();
756 } else {
757 ShouldNotReachHere();
758 }
759 }
760
761 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) {
762 int base = 0, scale = 0;
763 getBaseAndScale(base, scale, clazz, CHECK_0);
764
765 return field_offset_from_byte_offset(base);
766 } UNSAFE_END
767
768
769 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) {
770 int base = 0, scale = 0;
771 getBaseAndScale(base, scale, clazz, CHECK_0);
772
773 // This VM packs both fields and array elements down to the byte.
774 // But watch out: If this changes, so that array references for
775 // a given primitive type (say, T_BOOLEAN) use different memory units
776 // than fields, this method MUST return zero for such arrays.
777 // For example, the VM used to store sub-word sized fields in full
778 // words in the object layout, so that accessors like getByte(Object,int)
779 // did not really do what one might expect for arrays. Therefore,
780 // this function used to report a zero scale factor, so that the user
781 // would know not to attempt to access sub-word array elements.
782 // // Code for unpacked fields:
783 // if (scale < wordSize) return 0;
784
785 // The following allows for a pretty general fieldOffset cookie scheme,
786 // but requires it to be linear in byte offset.
787 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
788 } UNSAFE_END
789
790
791 UNSAFE_ENTRY(jlong, Unsafe_GetObjectSize0(JNIEnv* env, jobject o, jobject obj))
792 oop p = JNIHandles::resolve(obj);
793 return p->size() * HeapWordSize;
794 UNSAFE_END
795
796
797 static inline void throw_new(JNIEnv *env, const char *ename) {
798 jclass cls = env->FindClass(ename);
799 if (env->ExceptionCheck()) {
800 env->ExceptionClear();
801 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", ename);
802 return;
803 }
804
805 env->ThrowNew(cls, nullptr);
806 }
807
808 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
809 // Code lifted from JDK 1.3 ClassLoader.c
810
811 jbyte *body;
812 char *utfName = nullptr;
813 jclass result = nullptr;
814 char buf[128];
815
816 assert(data != nullptr, "Class bytes must not be null");
817 assert(length >= 0, "length must not be negative: %d", length);
818
819 if (UsePerfData) {
820 ClassLoader::unsafe_defineClassCallCounter()->inc();
821 }
822
823 body = NEW_C_HEAP_ARRAY_RETURN_NULL(jbyte, length, mtInternal);
824 if (body == nullptr) {
825 throw_new(env, "java/lang/OutOfMemoryError");
826 return nullptr;
827 }
828
829 env->GetByteArrayRegion(data, offset, length, body);
830 if (env->ExceptionCheck()) {
831 goto free_body;
832 }
833
834 if (name != nullptr) {
835 uint len = env->GetStringUTFLength(name);
836 int unicode_len = env->GetStringLength(name);
837
838 if (len >= sizeof(buf)) {
839 utfName = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len + 1, mtInternal);
840 if (utfName == nullptr) {
841 throw_new(env, "java/lang/OutOfMemoryError");
842 goto free_body;
843 }
844 } else {
845 utfName = buf;
846 }
847
848 env->GetStringUTFRegion(name, 0, unicode_len, utfName);
849
850 for (uint i = 0; i < len; i++) {
851 if (utfName[i] == '.') utfName[i] = '/';
852 }
853 }
854
855 result = JVM_DefineClass(env, utfName, loader, body, length, pd);
856
857 if (utfName && utfName != buf) {
858 FREE_C_HEAP_ARRAY(char, utfName);
859 }
860
861 free_body:
862 FREE_C_HEAP_ARRAY(jbyte, body);
863 return result;
864 }
865
866
867 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) {
868 ThreadToNativeFromVM ttnfv(thread);
869
870 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
871 } UNSAFE_END
872
873
874 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
875 ThreadToNativeFromVM ttnfv(thread);
876 env->Throw(thr);
877 } UNSAFE_END
878
879 // JSR166 ------------------------------------------------------------------
880
881 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
882 oop x = JNIHandles::resolve(x_h);
883 oop e = JNIHandles::resolve(e_h);
884 oop p = JNIHandles::resolve(obj);
885 assert_field_offset_sane(p, offset);
886 oop res = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x);
887 return JNIHandles::make_local(THREAD, res);
888 } UNSAFE_END
889
890 UNSAFE_ENTRY_SCOPED(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
891 oop p = JNIHandles::resolve(obj);
892 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
893 return Atomic::cmpxchg(addr, e, x);
894 } UNSAFE_END
895
896 UNSAFE_ENTRY_SCOPED(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
897 oop p = JNIHandles::resolve(obj);
898 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
899 return Atomic::cmpxchg(addr, e, x);
900 } UNSAFE_END
901
902 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
903 oop x = JNIHandles::resolve(x_h);
904 oop e = JNIHandles::resolve(e_h);
905 oop p = JNIHandles::resolve(obj);
906 assert_field_offset_sane(p, offset);
907 oop ret = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x);
908 return ret == e;
909 } UNSAFE_END
910
911 UNSAFE_ENTRY_SCOPED(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
912 oop p = JNIHandles::resolve(obj);
913 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
914 return Atomic::cmpxchg(addr, e, x) == e;
915 } UNSAFE_END
916
917 UNSAFE_ENTRY_SCOPED(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
918 oop p = JNIHandles::resolve(obj);
919 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
920 return Atomic::cmpxchg(addr, e, x) == e;
921 } UNSAFE_END
922
923 static void post_thread_park_event(EventThreadPark* event, const oop obj, jlong timeout_nanos, jlong until_epoch_millis) {
924 assert(event != nullptr, "invariant");
925 event->set_parkedClass((obj != nullptr) ? obj->klass() : nullptr);
926 event->set_timeout(timeout_nanos);
927 event->set_until(until_epoch_millis);
928 event->set_address((obj != nullptr) ? (u8)cast_from_oop<uintptr_t>(obj) : 0);
929 event->commit();
930 }
931
932 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
933 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
934 EventThreadPark event;
935
936 JavaThreadParkedState jtps(thread, time != 0);
937 thread->parker()->park(isAbsolute != 0, time);
938 if (event.should_commit()) {
939 const oop obj = thread->current_park_blocker();
940 if (time == 0) {
941 post_thread_park_event(&event, obj, min_jlong, min_jlong);
942 } else {
943 if (isAbsolute != 0) {
944 post_thread_park_event(&event, obj, min_jlong, time);
945 } else {
946 post_thread_park_event(&event, obj, time, min_jlong);
947 }
948 }
949 }
950 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
951 } UNSAFE_END
952
953 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
954 if (jthread != nullptr) {
955 oop thread_oop = JNIHandles::resolve_non_null(jthread);
956 // Get the JavaThread* stored in the java.lang.Thread object _before_
957 // the embedded ThreadsListHandle is constructed so we know if the
958 // early life stage of the JavaThread* is protected. We use acquire
959 // here to ensure that if we see a non-nullptr value, then we also
960 // see the main ThreadsList updates from the JavaThread* being added.
961 FastThreadsListHandle ftlh(thread_oop, java_lang_Thread::thread_acquire(thread_oop));
962 JavaThread* thr = ftlh.protected_java_thread();
963 if (thr != nullptr) {
964 // The still live JavaThread* is protected by the FastThreadsListHandle
965 // so it is safe to access.
966 Parker* p = thr->parker();
967 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
968 p->unpark();
969 }
970 } // FastThreadsListHandle is destroyed here.
971 } UNSAFE_END
972
973 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
974 const int max_nelem = 3;
975 double la[max_nelem];
976 jint ret;
977
978 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
979 assert(a->is_typeArray(), "must be type array");
980
981 ret = os::loadavg(la, nelem);
982 if (ret == -1) {
983 return -1;
984 }
985
986 // if successful, ret is the number of samples actually retrieved.
987 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
988 switch(ret) {
989 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
990 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
991 case 1: a->double_at_put(0, (jdouble)la[0]); break;
992 }
993
994 return ret;
995 } UNSAFE_END
996
997
998 /// JVM_RegisterUnsafeMethods
999
1000 #define ADR "J"
1001
1002 #define LANG "Ljava/lang/"
1003
1004 #define OBJ LANG "Object;"
1005 #define CLS LANG "Class;"
1006 #define FLD LANG "reflect/Field;"
1007 #define THR LANG "Throwable;"
1008
1009 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
1010 #define DAC_Args CLS "[B[" OBJ
1011
1012 #define CC (char*) /*cast a literal from (const char*)*/
1013 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1014
1015 #define DECLARE_GETPUTOOP(Type, Desc) \
1016 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
1017 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \
1018 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
1019 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)}
1020
1021
1022 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1023 {CC "getReference", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetReference)},
1024 {CC "putReference", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReference)},
1025 {CC "getReferenceVolatile", CC "(" OBJ "J)" OBJ, FN_PTR(Unsafe_GetReferenceVolatile)},
1026 {CC "putReferenceVolatile", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReferenceVolatile)},
1027
1028 {CC "isFlatArray", CC "(" CLS ")Z", FN_PTR(Unsafe_IsFlatArray)},
1029 {CC "isFlatField0", CC "(" OBJ ")Z", FN_PTR(Unsafe_IsFlatField)},
1030 {CC "hasNullMarker0" , CC "(" OBJ ")Z", FN_PTR(Unsafe_HasNullMarker)},
1031 {CC "nullMarkerOffset0", CC "(" OBJ ")I", FN_PTR(Unsafe_NullMarkerOffset)},
1032 {CC "getValue", CC "(" OBJ "J" CLS ")" OBJ, FN_PTR(Unsafe_GetValue)},
1033 {CC "putValue", CC "(" OBJ "J" CLS OBJ ")V", FN_PTR(Unsafe_PutValue)},
1034 {CC "uninitializedDefaultValue", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_UninitializedDefaultValue)},
1035 {CC "makePrivateBuffer", CC "(" OBJ ")" OBJ, FN_PTR(Unsafe_MakePrivateBuffer)},
1036 {CC "finishPrivateBuffer", CC "(" OBJ ")" OBJ, FN_PTR(Unsafe_FinishPrivateBuffer)},
1037 {CC "valueHeaderSize", CC "(" CLS ")J", FN_PTR(Unsafe_ValueHeaderSize)},
1038
1039 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1040
1041 DECLARE_GETPUTOOP(Boolean, Z),
1042 DECLARE_GETPUTOOP(Byte, B),
1043 DECLARE_GETPUTOOP(Short, S),
1044 DECLARE_GETPUTOOP(Char, C),
1045 DECLARE_GETPUTOOP(Int, I),
1046 DECLARE_GETPUTOOP(Long, J),
1047 DECLARE_GETPUTOOP(Float, F),
1048 DECLARE_GETPUTOOP(Double, D),
1049
1050 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1051 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1052 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1053
1054 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1055 {CC "objectFieldOffset1", CC "(" CLS LANG "String;)J", FN_PTR(Unsafe_ObjectFieldOffset1)},
1056 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1057 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1058 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1059 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1060 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1061 {CC "getObjectSize0", CC "(Ljava/lang/Object;)J", FN_PTR(Unsafe_GetObjectSize0)},
1062
1063 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1064 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1065 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1066 {CC "compareAndSetReference",CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSetReference)},
1067 {CC "compareAndSetInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSetInt)},
1068 {CC "compareAndSetLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSetLong)},
1069 {CC "compareAndExchangeReference", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeReference)},
1070 {CC "compareAndExchangeInt", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)},
1071 {CC "compareAndExchangeLong", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)},
1072
1073 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1074 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1075
1076 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1077
1078 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1079 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1080 {CC "writeback0", CC "(" "J" ")V", FN_PTR(Unsafe_WriteBack0)},
1081 {CC "writebackPreSync0", CC "()V", FN_PTR(Unsafe_WriteBackPreSync0)},
1082 {CC "writebackPostSync0", CC "()V", FN_PTR(Unsafe_WriteBackPostSync0)},
1083 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1084
1085 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1086
1087 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1088 };
1089
1090 #undef CC
1091 #undef FN_PTR
1092
1093 #undef ADR
1094 #undef LANG
1095 #undef OBJ
1096 #undef CLS
1097 #undef FLD
1098 #undef THR
1099 #undef DC_Args
1100 #undef DAC_Args
1101
1102 #undef DECLARE_GETPUTOOP
1103
1104
1105 // This function is exported, used by NativeLookup.
1106 // The Unsafe_xxx functions above are called only from the interpreter.
1107 // The optimizer looks at names and signatures to recognize
1108 // individual functions.
1109
1110 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1111 ThreadToNativeFromVM ttnfv(thread);
1112
1113 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1114 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1115 } JVM_END