1 /*
2 * Copyright (c) 2000, 2023, 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 "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 #define UNSAFE_ENTRY(result_type, header) \
80 JVM_ENTRY(static result_type, header)
81
82 #define UNSAFE_LEAF(result_type, header) \
83 JVM_LEAF(static result_type, header)
84
85 // Note that scoped accesses (cf. scopedMemoryAccess.cpp) can install
86 // an async handshake on the entry to an Unsafe method. When that happens,
87 // it is expected that we are not allowed to touch the underlying memory
88 // that might have gotten unmapped. Therefore, we check at the entry
89 // to unsafe functions, if we have such async exception conditions,
90 // and return immediately if that is the case.
91 //
92 // We also use NoSafepointVerifier to block potential safepoints.
93 // It would be problematic if an async exception handshake were installed later on
94 // during another safepoint in the function, but before the memory access happens,
95 // as the memory will be freed after the handshake is installed. We must notice
96 // the installed handshake and return early before doing the memory access to prevent
97 // accesses to freed memory.
98 //
99 // Note also that we MUST do a scoped memory access in the VM (or Java) thread
100 // state. Since we rely on a handshake to check for threads that are accessing
101 // scoped memory, and we need the handshaking thread to wait until we get to a
102 // safepoint, in order to make sure we are not in the middle of accessing memory
103 // that is about to be freed. (i.e. there can be no UNSAFE_LEAF_SCOPED)
104 #define UNSAFE_ENTRY_SCOPED(result_type, header) \
105 JVM_ENTRY(static result_type, header) \
106 if (thread->has_async_exception_condition()) {return (result_type)0;} \
107 NoSafepointVerifier nsv;
108
109 #define UNSAFE_END JVM_END
110
111
112 static inline void* addr_from_java(jlong addr) {
113 // This assert fails in a variety of ways on 32-bit systems.
114 // It is impossible to predict whether native code that converts
115 // pointers to longs will sign-extend or zero-extend the addresses.
116 //assert(addr == (uintptr_t)addr, "must not be odd high bits");
117 return (void*)(uintptr_t)addr;
118 }
119
120 static inline jlong addr_to_java(void* p) {
121 assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
122 return (uintptr_t)p;
123 }
124
125
126 // Note: The VM's obj_field and related accessors use byte-scaled
127 // ("unscaled") offsets, just as the unsafe methods do.
128
129 // However, the method Unsafe.fieldOffset explicitly declines to
130 // guarantee this. The field offset values manipulated by the Java user
131 // through the Unsafe API are opaque cookies that just happen to be byte
132 // offsets. We represent this state of affairs by passing the cookies
133 // through conversion functions when going between the VM and the Unsafe API.
134 // The conversion functions just happen to be no-ops at present.
135
136 static inline jlong field_offset_to_byte_offset(jlong field_offset) {
137 return field_offset;
138 }
139
140 static inline int field_offset_from_byte_offset(int byte_offset) {
141 return byte_offset;
142 }
143
144 static inline void assert_field_offset_sane(oop p, jlong field_offset) {
145 #ifdef ASSERT
146 jlong byte_offset = field_offset_to_byte_offset(field_offset);
147
148 if (p != nullptr) {
149 assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
150 if (byte_offset == (jint)byte_offset) {
151 void* ptr_plus_disp = cast_from_oop<address>(p) + byte_offset;
152 assert(p->field_addr<void>((jint)byte_offset) == ptr_plus_disp,
153 "raw [ptr+disp] must be consistent with oop::field_addr");
154 }
155 jlong p_size = HeapWordSize * (jlong)(p->size());
156 assert(byte_offset < p_size, "Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, (int64_t)byte_offset, (int64_t)p_size);
157 }
158 #endif
159 }
160
161 static inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
162 assert_field_offset_sane(p, field_offset);
163 jlong byte_offset = field_offset_to_byte_offset(field_offset);
164
165 if (sizeof(char*) == sizeof(jint)) { // (this constant folds!)
166 return cast_from_oop<address>(p) + (jint) byte_offset;
167 } else {
168 return cast_from_oop<address>(p) + byte_offset;
169 }
170 }
171
172 // Externally callable versions:
173 // (Use these in compiler intrinsics which emulate unsafe primitives.)
174 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
175 return field_offset;
176 }
177 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
178 return byte_offset;
179 }
180
181 ///// Data read/writes on the Java heap and in native (off-heap) memory
182
183 /**
184 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access()
185 */
186 class GuardUnsafeAccess {
187 JavaThread* _thread;
188
189 public:
190 GuardUnsafeAccess(JavaThread* thread) : _thread(thread) {
191 // native/off-heap access which may raise SIGBUS if accessing
192 // memory mapped file data in a region of the file which has
193 // been truncated and is now invalid.
194 _thread->set_doing_unsafe_access(true);
195 }
196
197 ~GuardUnsafeAccess() {
198 _thread->set_doing_unsafe_access(false);
199 }
200 };
201
202 /**
203 * Helper class for accessing memory.
204 *
205 * Normalizes values and wraps accesses in
206 * JavaThread::doing_unsafe_access() if needed.
207 */
208 template <typename T>
209 class MemoryAccess : StackObj {
210 JavaThread* _thread;
211 oop _obj;
212 ptrdiff_t _offset;
213
214 // Resolves and returns the address of the memory access.
215 // This raw memory access may fault, so we make sure it happens within the
216 // guarded scope by making the access volatile at least. Since the store
217 // of Thread::set_doing_unsafe_access() is also volatile, these accesses
218 // can not be reordered by the compiler. Therefore, if the access triggers
219 // a fault, we will know that Thread::doing_unsafe_access() returns true.
220 volatile T* addr() {
221 void* addr = index_oop_from_field_offset_long(_obj, _offset);
222 return static_cast<volatile T*>(addr);
223 }
224
225 template <typename U>
226 U normalize_for_write(U x) {
227 return x;
228 }
229
230 jboolean normalize_for_write(jboolean x) {
231 return x & 1;
232 }
233
234 template <typename U>
235 U normalize_for_read(U x) {
236 return x;
237 }
238
239 jboolean normalize_for_read(jboolean x) {
240 return x != 0;
241 }
242
243 public:
244 MemoryAccess(JavaThread* thread, jobject obj, jlong offset)
245 : _thread(thread), _obj(JNIHandles::resolve(obj)), _offset((ptrdiff_t)offset) {
246 assert_field_offset_sane(_obj, offset);
247 }
248
249 T get() {
250 GuardUnsafeAccess guard(_thread);
251 return normalize_for_read(*addr());
252 }
253
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_IsFlatArray(JNIEnv *env, jobject unsafe, jclass c)) {
366 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(c));
367 return k->is_flatArray_klass();
368 } UNSAFE_END
369
370 UNSAFE_ENTRY(jobject, Unsafe_UninitializedDefaultValue(JNIEnv *env, jobject unsafe, jclass vc)) {
371 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(vc));
372 InlineKlass* vk = InlineKlass::cast(k);
373 oop v = vk->default_value();
374 return JNIHandles::make_local(THREAD, v);
375 } UNSAFE_END
376
377 UNSAFE_ENTRY(jobject, Unsafe_GetValue(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jclass vc)) {
378 oop base = JNIHandles::resolve(obj);
379 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(vc));
380 InlineKlass* vk = InlineKlass::cast(k);
381 assert_and_log_unsafe_value_access(base, offset, vk);
382 Handle base_h(THREAD, base);
383 oop v = vk->read_flat_field(base_h(), offset, CHECK_NULL);
384 return JNIHandles::make_local(THREAD, v);
385 } UNSAFE_END
386
387 UNSAFE_ENTRY(void, Unsafe_PutValue(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jclass vc, jobject value)) {
388 oop base = JNIHandles::resolve(obj);
389 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(vc));
390 InlineKlass* vk = InlineKlass::cast(k);
391 assert(!base->is_inline_type() || base->mark().is_larval_state(), "must be an object instance or a larval inline type");
392 assert_and_log_unsafe_value_access(base, offset, vk);
393 oop v = JNIHandles::resolve(value);
394 vk->write_flat_field(base, offset, v, CHECK);
395 } UNSAFE_END
396
397 UNSAFE_ENTRY(jobject, Unsafe_MakePrivateBuffer(JNIEnv *env, jobject unsafe, jobject value)) {
398 oop v = JNIHandles::resolve_non_null(value);
399 assert(v->is_inline_type(), "must be an inline type instance");
400 Handle vh(THREAD, v);
401 InlineKlass* vk = InlineKlass::cast(v->klass());
402 instanceOop new_value = vk->allocate_instance_buffer(CHECK_NULL);
403 vk->inline_copy_oop_to_new_oop(vh(), new_value);
404 markWord mark = new_value->mark();
405 new_value->set_mark(mark.enter_larval_state());
406 return JNIHandles::make_local(THREAD, new_value);
407 } UNSAFE_END
408
409 UNSAFE_ENTRY(jobject, Unsafe_FinishPrivateBuffer(JNIEnv *env, jobject unsafe, jobject value)) {
410 oop v = JNIHandles::resolve(value);
411 assert(v->mark().is_larval_state(), "must be a larval value");
412 markWord mark = v->mark();
413 v->set_mark(mark.exit_larval_state());
414 return JNIHandles::make_local(THREAD, v);
415 } UNSAFE_END
416
417 UNSAFE_ENTRY(jobject, Unsafe_GetReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
418 oop p = JNIHandles::resolve(obj);
419 assert_field_offset_sane(p, offset);
420 oop v = HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
421 return JNIHandles::make_local(THREAD, v);
422 } UNSAFE_END
423
424 UNSAFE_ENTRY(void, Unsafe_PutReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
425 oop x = JNIHandles::resolve(x_h);
426 oop p = JNIHandles::resolve(obj);
427 assert_field_offset_sane(p, offset);
428 HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
429 } UNSAFE_END
430
431 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) {
432 oop v = *(oop*) (address) addr;
433 return JNIHandles::make_local(THREAD, v);
434 } UNSAFE_END
435
436 #define DEFINE_GETSETOOP(java_type, Type) \
437 \
438 UNSAFE_ENTRY_SCOPED(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
439 return MemoryAccess<java_type>(thread, obj, offset).get(); \
440 } UNSAFE_END \
441 \
442 UNSAFE_ENTRY_SCOPED(void, Unsafe_Put##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
443 MemoryAccess<java_type>(thread, obj, offset).put(x); \
444 } UNSAFE_END \
445 \
446 // END DEFINE_GETSETOOP.
447
448 DEFINE_GETSETOOP(jboolean, Boolean)
449 DEFINE_GETSETOOP(jbyte, Byte)
450 DEFINE_GETSETOOP(jshort, Short);
451 DEFINE_GETSETOOP(jchar, Char);
452 DEFINE_GETSETOOP(jint, Int);
453 DEFINE_GETSETOOP(jlong, Long);
454 DEFINE_GETSETOOP(jfloat, Float);
455 DEFINE_GETSETOOP(jdouble, Double);
456
457 #undef DEFINE_GETSETOOP
458
459 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \
460 \
461 UNSAFE_ENTRY_SCOPED(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
462 return MemoryAccess<java_type>(thread, obj, offset).get_volatile(); \
463 } UNSAFE_END \
464 \
465 UNSAFE_ENTRY_SCOPED(void, Unsafe_Put##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
466 MemoryAccess<java_type>(thread, obj, offset).put_volatile(x); \
467 } UNSAFE_END \
468 \
469 // END DEFINE_GETSETOOP_VOLATILE.
470
471 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
472 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
473 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
474 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
475 DEFINE_GETSETOOP_VOLATILE(jint, Int);
476 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
477 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
478 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
479
480 #undef DEFINE_GETSETOOP_VOLATILE
481
482 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
483 OrderAccess::fence();
484 } UNSAFE_END
485
486 ////// Allocation requests
487
488 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
489 JvmtiVMObjectAllocEventCollector oam;
490 instanceOop i = InstanceKlass::allocate_instance(JNIHandles::resolve_non_null(cls), CHECK_NULL);
491 return JNIHandles::make_local(THREAD, i);
492 } UNSAFE_END
493
494 UNSAFE_LEAF(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) {
495 size_t sz = (size_t)size;
496
497 assert(is_aligned(sz, HeapWordSize), "sz not aligned");
498
499 void* x = os::malloc(sz, mtOther);
500
501 return addr_to_java(x);
502 } UNSAFE_END
503
504 UNSAFE_LEAF(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) {
505 void* p = addr_from_java(addr);
506 size_t sz = (size_t)size;
507
508 assert(is_aligned(sz, HeapWordSize), "sz not aligned");
509
510 void* x = os::realloc(p, sz, mtOther);
511
512 return addr_to_java(x);
513 } UNSAFE_END
514
515 UNSAFE_LEAF(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) {
516 void* p = addr_from_java(addr);
517
518 os::free(p);
519 } UNSAFE_END
520
521 UNSAFE_ENTRY_SCOPED(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) {
522 size_t sz = (size_t)size;
523
524 oop base = JNIHandles::resolve(obj);
525 void* p = index_oop_from_field_offset_long(base, offset);
526
527 Copy::fill_to_memory_atomic(p, sz, value);
528 } UNSAFE_END
529
530 UNSAFE_ENTRY_SCOPED(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) {
531 size_t sz = (size_t)size;
532
533 oop srcp = JNIHandles::resolve(srcObj);
534 oop dstp = JNIHandles::resolve(dstObj);
535
536 void* src = index_oop_from_field_offset_long(srcp, srcOffset);
537 void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
538 {
539 GuardUnsafeAccess guard(thread);
540 if (StubRoutines::unsafe_arraycopy() != nullptr) {
541 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, thread));
542 StubRoutines::UnsafeArrayCopy_stub()(src, dst, sz);
543 } else {
544 Copy::conjoint_memory_atomic(src, dst, sz);
545 }
546 }
547 } UNSAFE_END
548
549 UNSAFE_ENTRY_SCOPED(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) {
550 size_t sz = (size_t)size;
551 size_t esz = (size_t)elemSize;
552
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 } UNSAFE_END
564
565 UNSAFE_LEAF (void, Unsafe_WriteBack0(JNIEnv *env, jobject unsafe, jlong line)) {
566 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
567 #ifdef ASSERT
568 if (TraceMemoryWriteback) {
569 tty->print_cr("Unsafe: writeback 0x%p", addr_from_java(line));
570 }
571 #endif
572
573 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, Thread::current()));
574 assert(StubRoutines::data_cache_writeback() != nullptr, "sanity");
575 (StubRoutines::DataCacheWriteback_stub())(addr_from_java(line));
576 } UNSAFE_END
577
578 static void doWriteBackSync0(bool is_pre)
579 {
580 MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXExec, Thread::current()));
581 assert(StubRoutines::data_cache_writeback_sync() != nullptr, "sanity");
582 (StubRoutines::DataCacheWritebackSync_stub())(is_pre);
583 }
584
585 UNSAFE_LEAF (void, Unsafe_WriteBackPreSync0(JNIEnv *env, jobject unsafe)) {
586 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
587 #ifdef ASSERT
588 if (TraceMemoryWriteback) {
589 tty->print_cr("Unsafe: writeback pre-sync");
590 }
591 #endif
592
593 doWriteBackSync0(true);
594 } UNSAFE_END
595
596 UNSAFE_LEAF (void, Unsafe_WriteBackPostSync0(JNIEnv *env, jobject unsafe)) {
597 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
598 #ifdef ASSERT
599 if (TraceMemoryWriteback) {
600 tty->print_cr("Unsafe: writeback pre-sync");
601 }
602 #endif
603
604 doWriteBackSync0(false);
605 } UNSAFE_END
606
607 ////// Random queries
608
609 static jlong find_field_offset(jclass clazz, jstring name, TRAPS) {
610 assert(clazz != nullptr, "clazz must not be null");
611 assert(name != nullptr, "name must not be null");
612
613 ResourceMark rm(THREAD);
614 char *utf_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
615
616 InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz)));
617
618 jint offset = -1;
619 for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
620 Symbol *name = fs.name();
621 if (name->equals(utf_name)) {
622 offset = fs.offset();
623 break;
624 }
625 }
626 if (offset < 0) {
627 THROW_0(vmSymbols::java_lang_InternalError());
628 }
629 return field_offset_from_byte_offset(offset);
630 }
631
632 static jlong find_field_offset(jobject field, int must_be_static, TRAPS) {
633 assert(field != nullptr, "field must not be null");
634
635 oop reflected = JNIHandles::resolve_non_null(field);
636 oop mirror = java_lang_reflect_Field::clazz(reflected);
637 Klass* k = java_lang_Class::as_Klass(mirror);
638 int slot = java_lang_reflect_Field::slot(reflected);
639 int modifiers = java_lang_reflect_Field::modifiers(reflected);
640
641 if (must_be_static >= 0) {
642 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
643 if (must_be_static != really_is_static) {
644 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
645 }
646 }
647
648 int offset = InstanceKlass::cast(k)->field_offset(slot);
649 return field_offset_from_byte_offset(offset);
650 }
651
652 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
653 return find_field_offset(field, 0, THREAD);
654 } UNSAFE_END
655
656 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset1(JNIEnv *env, jobject unsafe, jclass c, jstring name)) {
657 return find_field_offset(c, name, THREAD);
658 } UNSAFE_END
659
660 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
661 return find_field_offset(field, 1, THREAD);
662 } UNSAFE_END
663
664 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) {
665 assert(field != nullptr, "field must not be null");
666
667 // Note: In this VM implementation, a field address is always a short
668 // offset from the base of a klass metaobject. Thus, the full dynamic
669 // range of the return type is never used. However, some implementations
670 // might put the static field inside an array shared by many classes,
671 // or even at a fixed address, in which case the address could be quite
672 // large. In that last case, this function would return null, since
673 // the address would operate alone, without any base pointer.
674
675 oop reflected = JNIHandles::resolve_non_null(field);
676 oop mirror = java_lang_reflect_Field::clazz(reflected);
677 int modifiers = java_lang_reflect_Field::modifiers(reflected);
678
679 if ((modifiers & JVM_ACC_STATIC) == 0) {
680 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
681 }
682
683 return JNIHandles::make_local(THREAD, mirror);
684 } UNSAFE_END
685
686 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
687 assert(clazz != nullptr, "clazz must not be null");
688
689 oop mirror = JNIHandles::resolve_non_null(clazz);
690
691 Klass* klass = java_lang_Class::as_Klass(mirror);
692 if (klass != nullptr && klass->should_be_initialized()) {
693 InstanceKlass* k = InstanceKlass::cast(klass);
694 k->initialize(CHECK);
695 }
696 }
697 UNSAFE_END
698
699 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
700 assert(clazz != nullptr, "clazz must not be null");
701
702 oop mirror = JNIHandles::resolve_non_null(clazz);
703 Klass* klass = java_lang_Class::as_Klass(mirror);
704
705 if (klass != nullptr && klass->should_be_initialized()) {
706 return true;
707 }
708
709 return false;
710 }
711 UNSAFE_END
712
713 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) {
714 assert(clazz != nullptr, "clazz must not be null");
715
716 oop mirror = JNIHandles::resolve_non_null(clazz);
717 Klass* k = java_lang_Class::as_Klass(mirror);
718
719 if (k == nullptr || !k->is_array_klass()) {
720 THROW(vmSymbols::java_lang_InvalidClassException());
721 } else if (k->is_objArray_klass()) {
722 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
723 scale = heapOopSize;
724 } else if (k->is_typeArray_klass()) {
725 TypeArrayKlass* tak = TypeArrayKlass::cast(k);
726 base = tak->array_header_in_bytes();
727 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
728 scale = (1 << tak->log2_element_size());
729 } else if (k->is_flatArray_klass()) {
730 FlatArrayKlass* vak = FlatArrayKlass::cast(k);
731 InlineKlass* vklass = vak->element_klass();
732 base = vak->array_header_in_bytes();
733 scale = vak->element_byte_size();
734 } else {
735 ShouldNotReachHere();
736 }
737 }
738
739 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) {
740 int base = 0, scale = 0;
741 getBaseAndScale(base, scale, clazz, CHECK_0);
742
743 return field_offset_from_byte_offset(base);
744 } UNSAFE_END
745
746
747 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) {
748 int base = 0, scale = 0;
749 getBaseAndScale(base, scale, clazz, CHECK_0);
750
751 // This VM packs both fields and array elements down to the byte.
752 // But watch out: If this changes, so that array references for
753 // a given primitive type (say, T_BOOLEAN) use different memory units
754 // than fields, this method MUST return zero for such arrays.
755 // For example, the VM used to store sub-word sized fields in full
756 // words in the object layout, so that accessors like getByte(Object,int)
757 // did not really do what one might expect for arrays. Therefore,
758 // this function used to report a zero scale factor, so that the user
759 // would know not to attempt to access sub-word array elements.
760 // // Code for unpacked fields:
761 // if (scale < wordSize) return 0;
762
763 // The following allows for a pretty general fieldOffset cookie scheme,
764 // but requires it to be linear in byte offset.
765 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
766 } UNSAFE_END
767
768
769 UNSAFE_ENTRY(jlong, Unsafe_GetObjectSize0(JNIEnv* env, jobject o, jobject obj))
770 oop p = JNIHandles::resolve(obj);
771 return p->size() * HeapWordSize;
772 UNSAFE_END
773
774
775 static inline void throw_new(JNIEnv *env, const char *ename) {
776 jclass cls = env->FindClass(ename);
777 if (env->ExceptionCheck()) {
778 env->ExceptionClear();
779 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", ename);
780 return;
781 }
782
783 env->ThrowNew(cls, nullptr);
784 }
785
786 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
787 // Code lifted from JDK 1.3 ClassLoader.c
788
789 jbyte *body;
790 char *utfName = nullptr;
791 jclass result = 0;
792 char buf[128];
793
794 assert(data != nullptr, "Class bytes must not be null");
795 assert(length >= 0, "length must not be negative: %d", length);
796
797 if (UsePerfData) {
798 ClassLoader::unsafe_defineClassCallCounter()->inc();
799 }
800
801 body = NEW_C_HEAP_ARRAY_RETURN_NULL(jbyte, length, mtInternal);
802 if (body == nullptr) {
803 throw_new(env, "java/lang/OutOfMemoryError");
804 return 0;
805 }
806
807 env->GetByteArrayRegion(data, offset, length, body);
808 if (env->ExceptionOccurred()) {
809 goto free_body;
810 }
811
812 if (name != nullptr) {
813 uint len = env->GetStringUTFLength(name);
814 int unicode_len = env->GetStringLength(name);
815
816 if (len >= sizeof(buf)) {
817 utfName = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len + 1, mtInternal);
818 if (utfName == nullptr) {
819 throw_new(env, "java/lang/OutOfMemoryError");
820 goto free_body;
821 }
822 } else {
823 utfName = buf;
824 }
825
826 env->GetStringUTFRegion(name, 0, unicode_len, utfName);
827
828 for (uint i = 0; i < len; i++) {
829 if (utfName[i] == '.') utfName[i] = '/';
830 }
831 }
832
833 result = JVM_DefineClass(env, utfName, loader, body, length, pd);
834
835 if (utfName && utfName != buf) {
836 FREE_C_HEAP_ARRAY(char, utfName);
837 }
838
839 free_body:
840 FREE_C_HEAP_ARRAY(jbyte, body);
841 return result;
842 }
843
844
845 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) {
846 ThreadToNativeFromVM ttnfv(thread);
847
848 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
849 } UNSAFE_END
850
851
852 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
853 ThreadToNativeFromVM ttnfv(thread);
854 env->Throw(thr);
855 } UNSAFE_END
856
857 // JSR166 ------------------------------------------------------------------
858
859 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
860 oop x = JNIHandles::resolve(x_h);
861 oop e = JNIHandles::resolve(e_h);
862 oop p = JNIHandles::resolve(obj);
863 assert_field_offset_sane(p, offset);
864 oop res = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x);
865 return JNIHandles::make_local(THREAD, res);
866 } UNSAFE_END
867
868 UNSAFE_ENTRY_SCOPED(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
869 oop p = JNIHandles::resolve(obj);
870 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
871 return Atomic::cmpxchg(addr, e, x);
872 } UNSAFE_END
873
874 UNSAFE_ENTRY_SCOPED(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
875 oop p = JNIHandles::resolve(obj);
876 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
877 return Atomic::cmpxchg(addr, e, x);
878 } UNSAFE_END
879
880 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
881 oop x = JNIHandles::resolve(x_h);
882 oop e = JNIHandles::resolve(e_h);
883 oop p = JNIHandles::resolve(obj);
884 assert_field_offset_sane(p, offset);
885 oop ret = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x);
886 return ret == e;
887 } UNSAFE_END
888
889 UNSAFE_ENTRY_SCOPED(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
890 oop p = JNIHandles::resolve(obj);
891 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
892 return Atomic::cmpxchg(addr, e, x) == e;
893 } UNSAFE_END
894
895 UNSAFE_ENTRY_SCOPED(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
896 oop p = JNIHandles::resolve(obj);
897 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
898 return Atomic::cmpxchg(addr, e, x) == e;
899 } UNSAFE_END
900
901 static void post_thread_park_event(EventThreadPark* event, const oop obj, jlong timeout_nanos, jlong until_epoch_millis) {
902 assert(event != nullptr, "invariant");
903 event->set_parkedClass((obj != nullptr) ? obj->klass() : nullptr);
904 event->set_timeout(timeout_nanos);
905 event->set_until(until_epoch_millis);
906 event->set_address((obj != nullptr) ? (u8)cast_from_oop<uintptr_t>(obj) : 0);
907 event->commit();
908 }
909
910 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
911 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
912 EventThreadPark event;
913
914 JavaThreadParkedState jtps(thread, time != 0);
915 thread->parker()->park(isAbsolute != 0, time);
916 if (event.should_commit()) {
917 const oop obj = thread->current_park_blocker();
918 if (time == 0) {
919 post_thread_park_event(&event, obj, min_jlong, min_jlong);
920 } else {
921 if (isAbsolute != 0) {
922 post_thread_park_event(&event, obj, min_jlong, time);
923 } else {
924 post_thread_park_event(&event, obj, time, min_jlong);
925 }
926 }
927 }
928 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
929 } UNSAFE_END
930
931 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
932 if (jthread != nullptr) {
933 oop thread_oop = JNIHandles::resolve_non_null(jthread);
934 // Get the JavaThread* stored in the java.lang.Thread object _before_
935 // the embedded ThreadsListHandle is constructed so we know if the
936 // early life stage of the JavaThread* is protected. We use acquire
937 // here to ensure that if we see a non-nullptr value, then we also
938 // see the main ThreadsList updates from the JavaThread* being added.
939 FastThreadsListHandle ftlh(thread_oop, java_lang_Thread::thread_acquire(thread_oop));
940 JavaThread* thr = ftlh.protected_java_thread();
941 if (thr != nullptr) {
942 // The still live JavaThread* is protected by the FastThreadsListHandle
943 // so it is safe to access.
944 Parker* p = thr->parker();
945 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
946 p->unpark();
947 }
948 } // FastThreadsListHandle is destroyed here.
949 } UNSAFE_END
950
951 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
952 const int max_nelem = 3;
953 double la[max_nelem];
954 jint ret;
955
956 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
957 assert(a->is_typeArray(), "must be type array");
958
959 ret = os::loadavg(la, nelem);
960 if (ret == -1) {
961 return -1;
962 }
963
964 // if successful, ret is the number of samples actually retrieved.
965 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
966 switch(ret) {
967 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
968 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
969 case 1: a->double_at_put(0, (jdouble)la[0]); break;
970 }
971
972 return ret;
973 } UNSAFE_END
974
975
976 /// JVM_RegisterUnsafeMethods
977
978 #define ADR "J"
979
980 #define LANG "Ljava/lang/"
981
982 #define OBJ LANG "Object;"
983 #define CLS LANG "Class;"
984 #define FLD LANG "reflect/Field;"
985 #define THR LANG "Throwable;"
986
987 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
988 #define DAC_Args CLS "[B[" OBJ
989
990 #define CC (char*) /*cast a literal from (const char*)*/
991 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
992
993 #define DECLARE_GETPUTOOP(Type, Desc) \
994 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
995 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \
996 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
997 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)}
998
999
1000 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1001 {CC "getReference", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetReference)},
1002 {CC "putReference", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReference)},
1003 {CC "getReferenceVolatile", CC "(" OBJ "J)" OBJ, FN_PTR(Unsafe_GetReferenceVolatile)},
1004 {CC "putReferenceVolatile", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReferenceVolatile)},
1005
1006 {CC "isFlatArray", CC "(" CLS ")Z", FN_PTR(Unsafe_IsFlatArray)},
1007 {CC "isFlatField0", CC "(" OBJ ")Z", FN_PTR(Unsafe_IsFlatField)},
1008 {CC "getValue", CC "(" OBJ "J" CLS ")" OBJ, FN_PTR(Unsafe_GetValue)},
1009 {CC "putValue", CC "(" OBJ "J" CLS OBJ ")V", FN_PTR(Unsafe_PutValue)},
1010 {CC "uninitializedDefaultValue", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_UninitializedDefaultValue)},
1011 {CC "makePrivateBuffer", CC "(" OBJ ")" OBJ, FN_PTR(Unsafe_MakePrivateBuffer)},
1012 {CC "finishPrivateBuffer", CC "(" OBJ ")" OBJ, FN_PTR(Unsafe_FinishPrivateBuffer)},
1013 {CC "valueHeaderSize", CC "(" CLS ")J", FN_PTR(Unsafe_ValueHeaderSize)},
1014
1015 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1016
1017 DECLARE_GETPUTOOP(Boolean, Z),
1018 DECLARE_GETPUTOOP(Byte, B),
1019 DECLARE_GETPUTOOP(Short, S),
1020 DECLARE_GETPUTOOP(Char, C),
1021 DECLARE_GETPUTOOP(Int, I),
1022 DECLARE_GETPUTOOP(Long, J),
1023 DECLARE_GETPUTOOP(Float, F),
1024 DECLARE_GETPUTOOP(Double, D),
1025
1026 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1027 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1028 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1029
1030 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1031 {CC "objectFieldOffset1", CC "(" CLS LANG "String;)J", FN_PTR(Unsafe_ObjectFieldOffset1)},
1032 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1033 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1034 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1035 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1036 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1037 {CC "getObjectSize0", CC "(Ljava/lang/Object;)J", FN_PTR(Unsafe_GetObjectSize0)},
1038
1039 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1040 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1041 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1042 {CC "compareAndSetReference",CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSetReference)},
1043 {CC "compareAndSetInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSetInt)},
1044 {CC "compareAndSetLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSetLong)},
1045 {CC "compareAndExchangeReference", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeReference)},
1046 {CC "compareAndExchangeInt", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)},
1047 {CC "compareAndExchangeLong", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)},
1048
1049 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1050 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1051
1052 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1053
1054 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1055 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1056 {CC "writeback0", CC "(" "J" ")V", FN_PTR(Unsafe_WriteBack0)},
1057 {CC "writebackPreSync0", CC "()V", FN_PTR(Unsafe_WriteBackPreSync0)},
1058 {CC "writebackPostSync0", CC "()V", FN_PTR(Unsafe_WriteBackPostSync0)},
1059 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1060
1061 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1062
1063 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1064 };
1065
1066 #undef CC
1067 #undef FN_PTR
1068
1069 #undef ADR
1070 #undef LANG
1071 #undef OBJ
1072 #undef CLS
1073 #undef FLD
1074 #undef THR
1075 #undef DC_Args
1076 #undef DAC_Args
1077
1078 #undef DECLARE_GETPUTOOP
1079
1080
1081 // This function is exported, used by NativeLookup.
1082 // The Unsafe_xxx functions above are called only from the interpreter.
1083 // The optimizer looks at names and signatures to recognize
1084 // individual functions.
1085
1086 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1087 ThreadToNativeFromVM ttnfv(thread);
1088
1089 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1090 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1091 } JVM_END