1 /*
2 * Copyright (c) 2000, 2020, 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/javaClasses.inline.hpp"
31 #include "classfile/vmSymbols.hpp"
32 #include "jfr/jfrEvents.hpp"
33 #include "memory/allocation.inline.hpp"
34 #include "memory/resourceArea.hpp"
35 #include "oops/access.inline.hpp"
36 #include "oops/fieldStreams.inline.hpp"
37 #include "oops/instanceKlass.inline.hpp"
38 #include "oops/objArrayOop.inline.hpp"
39 #include "oops/oop.inline.hpp"
40 #include "oops/typeArrayOop.inline.hpp"
41 #include "prims/unsafe.hpp"
42 #include "runtime/globals.hpp"
43 #include "runtime/handles.inline.hpp"
44 #include "runtime/interfaceSupport.inline.hpp"
45 #include "runtime/jniHandles.inline.hpp"
46 #include "runtime/orderAccess.hpp"
47 #include "runtime/reflection.hpp"
48 #include "runtime/sharedRuntime.hpp"
49 #include "runtime/thread.hpp"
50 #include "runtime/threadSMR.hpp"
51 #include "runtime/vm_version.hpp"
52 #include "services/threadService.hpp"
53 #include "utilities/align.hpp"
54 #include "utilities/copy.hpp"
55 #include "utilities/dtrace.hpp"
56 #include "utilities/macros.hpp"
57
58 /**
59 * Implementation of the jdk.internal.misc.Unsafe class
60 */
61
62
63 #define MAX_OBJECT_SIZE \
64 ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
65 + ((julong)max_jint * sizeof(double)) )
66
67
68 #define UNSAFE_ENTRY(result_type, header) \
69 JVM_ENTRY(static result_type, header)
70
71 #define UNSAFE_LEAF(result_type, header) \
72 JVM_LEAF(static result_type, header)
73
74 #define UNSAFE_END JVM_END
75
76
77 static inline void* addr_from_java(jlong addr) {
78 // This assert fails in a variety of ways on 32-bit systems.
79 // It is impossible to predict whether native code that converts
80 // pointers to longs will sign-extend or zero-extend the addresses.
81 //assert(addr == (uintptr_t)addr, "must not be odd high bits");
82 return (void*)(uintptr_t)addr;
83 }
84
85 static inline jlong addr_to_java(void* p) {
86 assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
87 return (uintptr_t)p;
88 }
89
90
91 // Note: The VM's obj_field and related accessors use byte-scaled
92 // ("unscaled") offsets, just as the unsafe methods do.
93
94 // However, the method Unsafe.fieldOffset explicitly declines to
95 // guarantee this. The field offset values manipulated by the Java user
96 // through the Unsafe API are opaque cookies that just happen to be byte
97 // offsets. We represent this state of affairs by passing the cookies
98 // through conversion functions when going between the VM and the Unsafe API.
99 // The conversion functions just happen to be no-ops at present.
100
101 static inline jlong field_offset_to_byte_offset(jlong field_offset) {
102 return field_offset;
103 }
104
105 static inline jlong field_offset_from_byte_offset(jlong byte_offset) {
106 return byte_offset;
107 }
108
109 static inline void assert_field_offset_sane(oop p, jlong field_offset) {
110 #ifdef ASSERT
111 jlong byte_offset = field_offset_to_byte_offset(field_offset);
112
113 if (p != NULL) {
114 assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
115 if (byte_offset == (jint)byte_offset) {
116 void* ptr_plus_disp = cast_from_oop<address>(p) + byte_offset;
117 assert(p->field_addr_raw((jint)byte_offset) == ptr_plus_disp,
118 "raw [ptr+disp] must be consistent with oop::field_addr_raw");
119 }
120 jlong p_size = HeapWordSize * (jlong)(p->size());
121 assert(byte_offset < p_size, "Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, (int64_t)byte_offset, (int64_t)p_size);
122 }
123 #endif
124 }
125
126 static inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
127 assert_field_offset_sane(p, field_offset);
128 jlong byte_offset = field_offset_to_byte_offset(field_offset);
129
130 if (p != NULL) {
131 p = Access<>::resolve(p);
132 }
133
134 if (sizeof(char*) == sizeof(jint)) { // (this constant folds!)
135 return cast_from_oop<address>(p) + (jint) byte_offset;
136 } else {
137 return cast_from_oop<address>(p) + byte_offset;
138 }
139 }
140
141 // Externally callable versions:
142 // (Use these in compiler intrinsics which emulate unsafe primitives.)
143 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
144 return field_offset;
145 }
146 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
147 return byte_offset;
148 }
149
150
151 ///// Data read/writes on the Java heap and in native (off-heap) memory
152
153 /**
154 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access()
155 */
156 class GuardUnsafeAccess {
157 JavaThread* _thread;
158
159 public:
160 GuardUnsafeAccess(JavaThread* thread) : _thread(thread) {
161 // native/off-heap access which may raise SIGBUS if accessing
162 // memory mapped file data in a region of the file which has
163 // been truncated and is now invalid.
164 _thread->set_doing_unsafe_access(true);
165 }
166
167 ~GuardUnsafeAccess() {
168 _thread->set_doing_unsafe_access(false);
169 }
170 };
171
172 /**
173 * Helper class for accessing memory.
174 *
175 * Normalizes values and wraps accesses in
176 * JavaThread::doing_unsafe_access() if needed.
177 */
178 template <typename T>
179 class MemoryAccess : StackObj {
180 JavaThread* _thread;
181 oop _obj;
182 ptrdiff_t _offset;
183
184 // Resolves and returns the address of the memory access.
185 // This raw memory access may fault, so we make sure it happens within the
186 // guarded scope by making the access volatile at least. Since the store
187 // of Thread::set_doing_unsafe_access() is also volatile, these accesses
188 // can not be reordered by the compiler. Therefore, if the access triggers
189 // a fault, we will know that Thread::doing_unsafe_access() returns true.
190 volatile T* addr() {
191 void* addr = index_oop_from_field_offset_long(_obj, _offset);
192 return static_cast<volatile T*>(addr);
193 }
194
195 template <typename U>
196 U normalize_for_write(U x) {
197 return x;
198 }
199
200 jboolean normalize_for_write(jboolean x) {
201 return x & 1;
202 }
203
204 template <typename U>
205 U normalize_for_read(U x) {
206 return x;
207 }
208
209 jboolean normalize_for_read(jboolean x) {
210 return x != 0;
211 }
212
213 public:
214 MemoryAccess(JavaThread* thread, jobject obj, jlong offset)
215 : _thread(thread), _obj(JNIHandles::resolve(obj)), _offset((ptrdiff_t)offset) {
216 assert_field_offset_sane(_obj, offset);
217 }
218
219 T get() {
220 if (_obj == NULL) {
221 GuardUnsafeAccess guard(_thread);
222 T ret = RawAccess<>::load(addr());
223 return normalize_for_read(ret);
224 } else {
225 T ret = HeapAccess<>::load_at(_obj, _offset);
226 return normalize_for_read(ret);
227 }
228 }
229
230 void put(T x) {
231 if (_obj == NULL) {
232 GuardUnsafeAccess guard(_thread);
233 RawAccess<>::store(addr(), normalize_for_write(x));
234 } else {
235 HeapAccess<>::store_at(_obj, _offset, normalize_for_write(x));
236 }
237 }
238
239
240 T get_volatile() {
241 if (_obj == NULL) {
242 GuardUnsafeAccess guard(_thread);
243 volatile T ret = RawAccess<MO_SEQ_CST>::load(addr());
244 return normalize_for_read(ret);
245 } else {
246 T ret = HeapAccess<MO_SEQ_CST>::load_at(_obj, _offset);
247 return normalize_for_read(ret);
248 }
249 }
250
251 void put_volatile(T x) {
252 if (_obj == NULL) {
253 GuardUnsafeAccess guard(_thread);
254 RawAccess<MO_SEQ_CST>::store(addr(), normalize_for_write(x));
255 } else {
256 HeapAccess<MO_SEQ_CST>::store_at(_obj, _offset, normalize_for_write(x));
257 }
258 }
259 };
260
261 // These functions allow a null base pointer with an arbitrary address.
262 // But if the base pointer is non-null, the offset should make some sense.
263 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
264 UNSAFE_ENTRY(jobject, Unsafe_GetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
265 oop p = JNIHandles::resolve(obj);
266 assert_field_offset_sane(p, offset);
267 oop v = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
268 return JNIHandles::make_local(env, v);
269 } UNSAFE_END
270
271 UNSAFE_ENTRY(void, Unsafe_PutReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
272 oop x = JNIHandles::resolve(x_h);
273 oop p = JNIHandles::resolve(obj);
274 assert_field_offset_sane(p, offset);
275 HeapAccess<ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
276 } UNSAFE_END
277
278 UNSAFE_ENTRY(jobject, Unsafe_GetReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
279 oop p = JNIHandles::resolve(obj);
280 assert_field_offset_sane(p, offset);
281 oop v = HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
282 return JNIHandles::make_local(env, v);
283 } UNSAFE_END
284
285 UNSAFE_ENTRY(void, Unsafe_PutReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
286 oop x = JNIHandles::resolve(x_h);
287 oop p = JNIHandles::resolve(obj);
288 assert_field_offset_sane(p, offset);
289 HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
290 } UNSAFE_END
291
292 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) {
293 oop v = *(oop*) (address) addr;
294 return JNIHandles::make_local(env, v);
295 } UNSAFE_END
296
297 #define DEFINE_GETSETOOP(java_type, Type) \
298 \
299 UNSAFE_ENTRY(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
300 return MemoryAccess<java_type>(thread, obj, offset).get(); \
301 } UNSAFE_END \
302 \
303 UNSAFE_ENTRY(void, Unsafe_Put##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
304 MemoryAccess<java_type>(thread, obj, offset).put(x); \
305 } UNSAFE_END \
306 \
307 // END DEFINE_GETSETOOP.
308
309 DEFINE_GETSETOOP(jboolean, Boolean)
310 DEFINE_GETSETOOP(jbyte, Byte)
311 DEFINE_GETSETOOP(jshort, Short);
312 DEFINE_GETSETOOP(jchar, Char);
313 DEFINE_GETSETOOP(jint, Int);
314 DEFINE_GETSETOOP(jlong, Long);
315 DEFINE_GETSETOOP(jfloat, Float);
316 DEFINE_GETSETOOP(jdouble, Double);
317
318 #undef DEFINE_GETSETOOP
319
320 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \
321 \
322 UNSAFE_ENTRY(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
323 return MemoryAccess<java_type>(thread, obj, offset).get_volatile(); \
324 } UNSAFE_END \
325 \
326 UNSAFE_ENTRY(void, Unsafe_Put##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
327 MemoryAccess<java_type>(thread, obj, offset).put_volatile(x); \
328 } UNSAFE_END \
329 \
330 // END DEFINE_GETSETOOP_VOLATILE.
331
332 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
333 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
334 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
335 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
336 DEFINE_GETSETOOP_VOLATILE(jint, Int);
337 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
338 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
339 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
340
341 #undef DEFINE_GETSETOOP_VOLATILE
342
343 UNSAFE_LEAF(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe)) {
344 OrderAccess::acquire();
345 } UNSAFE_END
346
347 UNSAFE_LEAF(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe)) {
348 OrderAccess::release();
349 } UNSAFE_END
350
351 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
352 OrderAccess::fence();
353 } UNSAFE_END
354
355 ////// Allocation requests
356
357 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
358 instanceOop i = InstanceKlass::allocate_instance(JNIHandles::resolve_non_null(cls), CHECK_NULL);
359 return JNIHandles::make_local(env, i);
360 } UNSAFE_END
361
362 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) {
363 size_t sz = (size_t)size;
364
365 assert(is_aligned(sz, HeapWordSize), "sz not aligned");
366
367 void* x = os::malloc(sz, mtOther);
368
369 return addr_to_java(x);
370 } UNSAFE_END
371
372 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) {
373 void* p = addr_from_java(addr);
374 size_t sz = (size_t)size;
375
376 assert(is_aligned(sz, HeapWordSize), "sz not aligned");
377
378 void* x = os::realloc(p, sz, mtOther);
379
380 return addr_to_java(x);
381 } UNSAFE_END
382
383 UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) {
384 void* p = addr_from_java(addr);
385
386 os::free(p);
387 } UNSAFE_END
388
389 UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) {
390 size_t sz = (size_t)size;
391
392 oop base = JNIHandles::resolve(obj);
393 void* p = index_oop_from_field_offset_long(base, offset);
394
395 Copy::fill_to_memory_atomic(p, sz, value);
396 } UNSAFE_END
397
398 UNSAFE_ENTRY(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) {
399 size_t sz = (size_t)size;
400
401 oop srcp = JNIHandles::resolve(srcObj);
402 oop dstp = JNIHandles::resolve(dstObj);
403
404 void* src = index_oop_from_field_offset_long(srcp, srcOffset);
405 void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
406 {
407 GuardUnsafeAccess guard(thread);
408 if (StubRoutines::unsafe_arraycopy() != NULL) {
409 StubRoutines::UnsafeArrayCopy_stub()(src, dst, sz);
410 } else {
411 Copy::conjoint_memory_atomic(src, dst, sz);
412 }
413 }
414 } UNSAFE_END
415
416 // This function is a leaf since if the source and destination are both in native memory
417 // the copy may potentially be very large, and we don't want to disable GC if we can avoid it.
418 // If either source or destination (or both) are on the heap, the function will enter VM using
419 // JVM_ENTRY_FROM_LEAF
420 UNSAFE_LEAF(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) {
421 size_t sz = (size_t)size;
422 size_t esz = (size_t)elemSize;
423
424 if (srcObj == NULL && dstObj == NULL) {
425 // Both src & dst are in native memory
426 address src = (address)srcOffset;
427 address dst = (address)dstOffset;
428
429 {
430 JavaThread* thread = JavaThread::thread_from_jni_environment(env);
431 GuardUnsafeAccess guard(thread);
432 Copy::conjoint_swap(src, dst, sz, esz);
433 }
434 } else {
435 // At least one of src/dst are on heap, transition to VM to access raw pointers
436
437 JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) {
438 oop srcp = JNIHandles::resolve(srcObj);
439 oop dstp = JNIHandles::resolve(dstObj);
440
441 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset);
442 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset);
443
444 {
445 GuardUnsafeAccess guard(thread);
446 Copy::conjoint_swap(src, dst, sz, esz);
447 }
448 } JVM_END
449 }
450 } UNSAFE_END
451
452 UNSAFE_LEAF (void, Unsafe_WriteBack0(JNIEnv *env, jobject unsafe, jlong line)) {
453 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
454 #ifdef ASSERT
455 if (TraceMemoryWriteback) {
456 tty->print_cr("Unsafe: writeback 0x%p", addr_from_java(line));
457 }
458 #endif
459
460 assert(StubRoutines::data_cache_writeback() != NULL, "sanity");
461 (StubRoutines::DataCacheWriteback_stub())(addr_from_java(line));
462 } UNSAFE_END
463
464 static void doWriteBackSync0(bool is_pre)
465 {
466 assert(StubRoutines::data_cache_writeback_sync() != NULL, "sanity");
467 (StubRoutines::DataCacheWritebackSync_stub())(is_pre);
468 }
469
470 UNSAFE_LEAF (void, Unsafe_WriteBackPreSync0(JNIEnv *env, jobject unsafe)) {
471 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
472 #ifdef ASSERT
473 if (TraceMemoryWriteback) {
474 tty->print_cr("Unsafe: writeback pre-sync");
475 }
476 #endif
477
478 doWriteBackSync0(true);
479 } UNSAFE_END
480
481 UNSAFE_LEAF (void, Unsafe_WriteBackPostSync0(JNIEnv *env, jobject unsafe)) {
482 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
483 #ifdef ASSERT
484 if (TraceMemoryWriteback) {
485 tty->print_cr("Unsafe: writeback pre-sync");
486 }
487 #endif
488
489 doWriteBackSync0(false);
490 } UNSAFE_END
491
492 ////// Random queries
493
494 static jlong find_field_offset(jclass clazz, jstring name, TRAPS) {
495 assert(clazz != NULL, "clazz must not be NULL");
496 assert(name != NULL, "name must not be NULL");
497
498 ResourceMark rm(THREAD);
499 char *utf_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
500
501 InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz)));
502
503 jint offset = -1;
504 for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
505 Symbol *name = fs.name();
506 if (name->equals(utf_name)) {
507 offset = fs.offset();
508 break;
509 }
510 }
511 if (offset < 0) {
512 THROW_0(vmSymbols::java_lang_InternalError());
513 }
514 return field_offset_from_byte_offset(offset);
515 }
516
517 static jlong find_field_offset(jobject field, int must_be_static, TRAPS) {
518 assert(field != NULL, "field must not be NULL");
519
520 oop reflected = JNIHandles::resolve_non_null(field);
521 oop mirror = java_lang_reflect_Field::clazz(reflected);
522 Klass* k = java_lang_Class::as_Klass(mirror);
523 int slot = java_lang_reflect_Field::slot(reflected);
524 int modifiers = java_lang_reflect_Field::modifiers(reflected);
525
526 if (must_be_static >= 0) {
527 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
528 if (must_be_static != really_is_static) {
529 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
530 }
531 }
532
533 int offset = InstanceKlass::cast(k)->field_offset(slot);
534 return field_offset_from_byte_offset(offset);
535 }
536
537 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
538 return find_field_offset(field, 0, THREAD);
539 } UNSAFE_END
540
541 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset1(JNIEnv *env, jobject unsafe, jclass c, jstring name)) {
542 return find_field_offset(c, name, THREAD);
543 } UNSAFE_END
544
545 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
546 return find_field_offset(field, 1, THREAD);
547 } UNSAFE_END
548
549 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) {
550 assert(field != NULL, "field must not be NULL");
551
552 // Note: In this VM implementation, a field address is always a short
553 // offset from the base of a a klass metaobject. Thus, the full dynamic
554 // range of the return type is never used. However, some implementations
555 // might put the static field inside an array shared by many classes,
556 // or even at a fixed address, in which case the address could be quite
557 // large. In that last case, this function would return NULL, since
558 // the address would operate alone, without any base pointer.
559
560 oop reflected = JNIHandles::resolve_non_null(field);
561 oop mirror = java_lang_reflect_Field::clazz(reflected);
562 int modifiers = java_lang_reflect_Field::modifiers(reflected);
563
564 if ((modifiers & JVM_ACC_STATIC) == 0) {
565 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
566 }
567
568 return JNIHandles::make_local(env, mirror);
569 } UNSAFE_END
570
571 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
572 assert(clazz != NULL, "clazz must not be NULL");
573
574 oop mirror = JNIHandles::resolve_non_null(clazz);
575
576 Klass* klass = java_lang_Class::as_Klass(mirror);
577 if (klass != NULL && klass->should_be_initialized()) {
578 InstanceKlass* k = InstanceKlass::cast(klass);
579 k->initialize(CHECK);
580 }
581 }
582 UNSAFE_END
583
584 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
585 assert(clazz != NULL, "clazz must not be NULL");
586
587 oop mirror = JNIHandles::resolve_non_null(clazz);
588 Klass* klass = java_lang_Class::as_Klass(mirror);
589
590 if (klass != NULL && klass->should_be_initialized()) {
591 return true;
592 }
593
594 return false;
595 }
596 UNSAFE_END
597
598 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) {
599 assert(clazz != NULL, "clazz must not be NULL");
600
601 oop mirror = JNIHandles::resolve_non_null(clazz);
602 Klass* k = java_lang_Class::as_Klass(mirror);
603
604 if (k == NULL || !k->is_array_klass()) {
605 THROW(vmSymbols::java_lang_InvalidClassException());
606 } else if (k->is_objArray_klass()) {
607 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
608 scale = heapOopSize;
609 } else if (k->is_typeArray_klass()) {
610 TypeArrayKlass* tak = TypeArrayKlass::cast(k);
611 base = tak->array_header_in_bytes();
612 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
613 scale = (1 << tak->log2_element_size());
614 } else {
615 ShouldNotReachHere();
616 }
617 }
618
619 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) {
620 int base = 0, scale = 0;
621 getBaseAndScale(base, scale, clazz, CHECK_0);
622
623 return field_offset_from_byte_offset(base);
624 } UNSAFE_END
625
626
627 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) {
628 int base = 0, scale = 0;
629 getBaseAndScale(base, scale, clazz, CHECK_0);
630
631 // This VM packs both fields and array elements down to the byte.
632 // But watch out: If this changes, so that array references for
633 // a given primitive type (say, T_BOOLEAN) use different memory units
634 // than fields, this method MUST return zero for such arrays.
635 // For example, the VM used to store sub-word sized fields in full
636 // words in the object layout, so that accessors like getByte(Object,int)
637 // did not really do what one might expect for arrays. Therefore,
638 // this function used to report a zero scale factor, so that the user
639 // would know not to attempt to access sub-word array elements.
640 // // Code for unpacked fields:
641 // if (scale < wordSize) return 0;
642
643 // The following allows for a pretty general fieldOffset cookie scheme,
644 // but requires it to be linear in byte offset.
645 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
646 } UNSAFE_END
647
648
649 static inline void throw_new(JNIEnv *env, const char *ename) {
650 jclass cls = env->FindClass(ename);
651 if (env->ExceptionCheck()) {
652 env->ExceptionClear();
653 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", ename);
654 return;
655 }
656
657 env->ThrowNew(cls, NULL);
658 }
659
660 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
661 // Code lifted from JDK 1.3 ClassLoader.c
662
663 jbyte *body;
664 char *utfName = NULL;
665 jclass result = 0;
666 char buf[128];
667
668 assert(data != NULL, "Class bytes must not be NULL");
669 assert(length >= 0, "length must not be negative: %d", length);
670
671 if (UsePerfData) {
672 ClassLoader::unsafe_defineClassCallCounter()->inc();
673 }
674
675 body = NEW_C_HEAP_ARRAY_RETURN_NULL(jbyte, length, mtInternal);
676 if (body == NULL) {
677 throw_new(env, "java/lang/OutOfMemoryError");
678 return 0;
679 }
680
681 env->GetByteArrayRegion(data, offset, length, body);
682 if (env->ExceptionOccurred()) {
683 goto free_body;
684 }
685
686 if (name != NULL) {
687 uint len = env->GetStringUTFLength(name);
688 int unicode_len = env->GetStringLength(name);
689
690 if (len >= sizeof(buf)) {
691 utfName = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len + 1, mtInternal);
692 if (utfName == NULL) {
693 throw_new(env, "java/lang/OutOfMemoryError");
694 goto free_body;
695 }
696 } else {
697 utfName = buf;
698 }
699
700 env->GetStringUTFRegion(name, 0, unicode_len, utfName);
701
702 for (uint i = 0; i < len; i++) {
703 if (utfName[i] == '.') utfName[i] = '/';
704 }
705 }
706
707 result = JVM_DefineClass(env, utfName, loader, body, length, pd);
708
709 if (utfName && utfName != buf) {
710 FREE_C_HEAP_ARRAY(char, utfName);
711 }
712
713 free_body:
714 FREE_C_HEAP_ARRAY(jbyte, body);
715 return result;
716 }
717
718
719 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) {
720 ThreadToNativeFromVM ttnfv(thread);
721
722 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
723 } UNSAFE_END
724
725
726 // define a class but do not make it known to the class loader or system dictionary
727 // - host_class: supplies context for linkage, access control, protection domain, and class loader
728 // if host_class is itself anonymous then it is replaced with its host class.
729 // - data: bytes of a class file, a raw memory address (length gives the number of bytes)
730 // - cp_patches: where non-null entries exist, they replace corresponding CP entries in data
731
732 // When you load an anonymous class U, it works as if you changed its name just before loading,
733 // to a name that you will never use again. Since the name is lost, no other class can directly
734 // link to any member of U. Just after U is loaded, the only way to use it is reflectively,
735 // through java.lang.Class methods like Class.newInstance.
736
737 // The package of an anonymous class must either match its host's class's package or be in the
738 // unnamed package. If it is in the unnamed package then it will be put in its host class's
739 // package.
740 //
741
742 // Access checks for linkage sites within U continue to follow the same rules as for named classes.
743 // An anonymous class also has special privileges to access any member of its host class.
744 // This is the main reason why this loading operation is unsafe. The purpose of this is to
745 // allow language implementations to simulate "open classes"; a host class in effect gets
746 // new code when an anonymous class is loaded alongside it. A less convenient but more
747 // standard way to do this is with reflection, which can also be set to ignore access
748 // restrictions.
749
750 // Access into an anonymous class is possible only through reflection. Therefore, there
751 // are no special access rules for calling into an anonymous class. The relaxed access
752 // rule for the host class is applied in the opposite direction: A host class reflectively
753 // access one of its anonymous classes.
754
755 // If you load the same bytecodes twice, you get two different classes. You can reload
756 // the same bytecodes with or without varying CP patches.
757
758 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
759 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
760 // The CONSTANT_Class entry for that name can be patched to refer directly to U1.
761
762 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as
763 // an outer class (so that U2 is an anonymous inner class of anonymous U1).
764 // It is not possible for a named class, or an older anonymous class, to refer by
765 // name (via its CP) to a newer anonymous class.
766
767 // CP patching may also be used to modify (i.e., hack) the names of methods, classes,
768 // or type descriptors used in the loaded anonymous class.
769
770 // Finally, CP patching may be used to introduce "live" objects into the constant pool,
771 // instead of "dead" strings. A compiled statement like println((Object)"hello") can
772 // be changed to println(greeting), where greeting is an arbitrary object created before
773 // the anonymous class is loaded. This is useful in dynamic languages, in which
774 // various kinds of metaobjects must be introduced as constants into bytecode.
775 // Note the cast (Object), which tells the verifier to expect an arbitrary object,
776 // not just a literal string. For such ldc instructions, the verifier uses the
777 // type Object instead of String, if the loaded constant is not in fact a String.
778
779 static InstanceKlass*
780 Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
781 jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
782 u1** temp_alloc,
783 TRAPS) {
784 assert(host_class != NULL, "host_class must not be NULL");
785 assert(data != NULL, "data must not be NULL");
786
787 if (UsePerfData) {
788 ClassLoader::unsafe_defineClassCallCounter()->inc();
789 }
790
791 jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
792 assert(length >= 0, "class_bytes_length must not be negative: %d", length);
793
794 int class_bytes_length = (int) length;
795
796 u1* class_bytes = NEW_C_HEAP_ARRAY_RETURN_NULL(u1, length, mtInternal);
797 if (class_bytes == NULL) {
798 THROW_0(vmSymbols::java_lang_OutOfMemoryError());
799 }
800
801 // caller responsible to free it:
802 *temp_alloc = class_bytes;
803
804 ArrayAccess<>::arraycopy_to_native(arrayOop(JNIHandles::resolve_non_null(data)), typeArrayOopDesc::element_offset<jbyte>(0),
805 reinterpret_cast<jbyte*>(class_bytes), length);
806
807 objArrayHandle cp_patches_h;
808 if (cp_patches_jh != NULL) {
809 oop p = JNIHandles::resolve_non_null(cp_patches_jh);
810 assert(p->is_objArray(), "cp_patches must be an object[]");
811 cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
812 }
813
814 const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class));
815
816 // Make sure it's the real host class, not another anonymous class.
817 while (host_klass != NULL && host_klass->is_instance_klass() &&
818 InstanceKlass::cast(host_klass)->is_unsafe_anonymous()) {
819 host_klass = InstanceKlass::cast(host_klass)->unsafe_anonymous_host();
820 }
821
822 // Primitive types have NULL Klass* fields in their java.lang.Class instances.
823 if (host_klass == NULL) {
824 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Host class is null");
825 }
826
827 assert(host_klass->is_instance_klass(), "Host class must be an instance class");
828
829 const char* host_source = host_klass->external_name();
830 Handle host_loader(THREAD, host_klass->class_loader());
831 Handle host_domain(THREAD, host_klass->protection_domain());
832
833 GrowableArray<Handle>* cp_patches = NULL;
834
835 if (cp_patches_h.not_null()) {
836 int alen = cp_patches_h->length();
837
838 for (int i = alen-1; i >= 0; i--) {
839 oop p = cp_patches_h->obj_at(i);
840 if (p != NULL) {
841 Handle patch(THREAD, p);
842
843 if (cp_patches == NULL) {
844 cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
845 }
846
847 cp_patches->at_put(i, patch);
848 }
849 }
850 }
851
852 ClassFileStream st(class_bytes, class_bytes_length, host_source, ClassFileStream::verify);
853
854 Symbol* no_class_name = NULL;
855 ClassLoadInfo cl_info(host_domain,
856 InstanceKlass::cast(host_klass),
857 cp_patches,
858 NULL, // dynamic_nest_host
859 Handle(), // classData
860 false, // is_hidden
861 false, // is_strong_hidden
862 true); // can_access_vm_annotations
863
864 Klass* anonk = SystemDictionary::parse_stream(no_class_name,
865 host_loader,
866 &st,
867 cl_info,
868 CHECK_NULL);
869 if (anonk == NULL) {
870 return NULL;
871 }
872
873 return InstanceKlass::cast(anonk);
874 }
875
876 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) {
877 ResourceMark rm(THREAD);
878
879 jobject res_jh = NULL;
880 u1* temp_alloc = NULL;
881
882 InstanceKlass* anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data, cp_patches_jh, &temp_alloc, THREAD);
883 if (anon_klass != NULL) {
884 res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
885 }
886
887 // try/finally clause:
888 FREE_C_HEAP_ARRAY(u1, temp_alloc);
889
890 // The anonymous class loader data has been artificially been kept alive to
891 // this point. The mirror and any instances of this class have to keep
892 // it alive afterwards.
893 if (anon_klass != NULL) {
894 anon_klass->class_loader_data()->dec_keep_alive();
895 }
896
897 // let caller initialize it as needed...
898
899 return (jclass) res_jh;
900 } UNSAFE_END
901
902
903
904 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
905 ThreadToNativeFromVM ttnfv(thread);
906 env->Throw(thr);
907 } UNSAFE_END
908
909 // JSR166 ------------------------------------------------------------------
910
911 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
912 oop x = JNIHandles::resolve(x_h);
913 oop e = JNIHandles::resolve(e_h);
914 oop p = JNIHandles::resolve(obj);
915 assert_field_offset_sane(p, offset);
916 oop res = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x);
917 return JNIHandles::make_local(env, res);
918 } UNSAFE_END
919
920 UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
921 oop p = JNIHandles::resolve(obj);
922 if (p == NULL) {
923 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
924 return RawAccess<>::atomic_cmpxchg(addr, e, x);
925 } else {
926 assert_field_offset_sane(p, offset);
927 return HeapAccess<>::atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x);
928 }
929 } UNSAFE_END
930
931 UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
932 oop p = JNIHandles::resolve(obj);
933 if (p == NULL) {
934 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
935 return RawAccess<>::atomic_cmpxchg(addr, e, x);
936 } else {
937 assert_field_offset_sane(p, offset);
938 return HeapAccess<>::atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x);
939 }
940 } UNSAFE_END
941
942 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
943 oop x = JNIHandles::resolve(x_h);
944 oop e = JNIHandles::resolve(e_h);
945 oop p = JNIHandles::resolve(obj);
946 assert_field_offset_sane(p, offset);
947 oop ret = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x);
948 return ret == e;
949 } UNSAFE_END
950
951 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
952 oop p = JNIHandles::resolve(obj);
953 GuardUnsafeAccess guard(thread);
954 if (p == NULL) {
955 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
956 return RawAccess<>::atomic_cmpxchg(addr, e, x) == e;
957 } else {
958 assert_field_offset_sane(p, offset);
959 return HeapAccess<>::atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x) == e;
960 }
961 } UNSAFE_END
962
963 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
964 oop p = JNIHandles::resolve(obj);
965 GuardUnsafeAccess guard(thread);
966 if (p == NULL) {
967 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
968 return RawAccess<>::atomic_cmpxchg(addr, e, x) == e;
969 } else {
970 assert_field_offset_sane(p, offset);
971 return HeapAccess<>::atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x) == e;
972 }
973 } UNSAFE_END
974
975 static void post_thread_park_event(EventThreadPark* event, const oop obj, jlong timeout_nanos, jlong until_epoch_millis) {
976 assert(event != NULL, "invariant");
977 assert(event->should_commit(), "invariant");
978 event->set_parkedClass((obj != NULL) ? obj->klass() : NULL);
979 event->set_timeout(timeout_nanos);
980 event->set_until(until_epoch_millis);
981 event->set_address((obj != NULL) ? (u8)cast_from_oop<uintptr_t>(obj) : 0);
982 event->commit();
983 }
984
985 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
986 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
987 EventThreadPark event;
988
989 JavaThreadParkedState jtps(thread, time != 0);
990 thread->parker()->park(isAbsolute != 0, time);
991 if (event.should_commit()) {
992 const oop obj = thread->current_park_blocker();
993 if (time == 0) {
994 post_thread_park_event(&event, obj, min_jlong, min_jlong);
995 } else {
996 if (isAbsolute != 0) {
997 post_thread_park_event(&event, obj, min_jlong, time);
998 } else {
999 post_thread_park_event(&event, obj, time, min_jlong);
1000 }
1001 }
1002 }
1003 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
1004 } UNSAFE_END
1005
1006 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
1007 Parker* p = NULL;
1008
1009 if (jthread != NULL) {
1010 ThreadsListHandle tlh;
1011 JavaThread* thr = NULL;
1012 oop java_thread = NULL;
1013 (void) tlh.cv_internal_thread_to_JavaThread(jthread, &thr, &java_thread);
1014 if (java_thread != NULL) {
1015 // This is a valid oop.
1016 if (thr != NULL) {
1017 // The JavaThread is alive.
1018 p = thr->parker();
1019 }
1020 }
1021 } // ThreadsListHandle is destroyed here.
1022
1023 // 'p' points to type-stable-memory if non-NULL. If the target
1024 // thread terminates before we get here the new user of this
1025 // Parker will get a 'spurious' unpark - which is perfectly valid.
1026 if (p != NULL) {
1027 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
1028 p->unpark();
1029 }
1030 } UNSAFE_END
1031
1032 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
1033 const int max_nelem = 3;
1034 double la[max_nelem];
1035 jint ret;
1036
1037 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
1038 assert(a->is_typeArray(), "must be type array");
1039
1040 ret = os::loadavg(la, nelem);
1041 if (ret == -1) {
1042 return -1;
1043 }
1044
1045 // if successful, ret is the number of samples actually retrieved.
1046 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
1047 switch(ret) {
1048 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
1049 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
1050 case 1: a->double_at_put(0, (jdouble)la[0]); break;
1051 }
1052
1053 return ret;
1054 } UNSAFE_END
1055
1056
1057 /// JVM_RegisterUnsafeMethods
1058
1059 #define ADR "J"
1060
1061 #define LANG "Ljava/lang/"
1062
1063 #define OBJ LANG "Object;"
1064 #define CLS LANG "Class;"
1065 #define FLD LANG "reflect/Field;"
1066 #define THR LANG "Throwable;"
1067
1068 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
1069 #define DAC_Args CLS "[B[" OBJ
1070
1071 #define CC (char*) /*cast a literal from (const char*)*/
1072 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1073
1074 #define DECLARE_GETPUTOOP(Type, Desc) \
1075 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
1076 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \
1077 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
1078 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)}
1079
1080
1081 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1082 {CC "getReference", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetReference)},
1083 {CC "putReference", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReference)},
1084 {CC "getReferenceVolatile", CC "(" OBJ "J)" OBJ, FN_PTR(Unsafe_GetReferenceVolatile)},
1085 {CC "putReferenceVolatile", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReferenceVolatile)},
1086
1087 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1088
1089 DECLARE_GETPUTOOP(Boolean, Z),
1090 DECLARE_GETPUTOOP(Byte, B),
1091 DECLARE_GETPUTOOP(Short, S),
1092 DECLARE_GETPUTOOP(Char, C),
1093 DECLARE_GETPUTOOP(Int, I),
1094 DECLARE_GETPUTOOP(Long, J),
1095 DECLARE_GETPUTOOP(Float, F),
1096 DECLARE_GETPUTOOP(Double, D),
1097
1098 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1099 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1100 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1101
1102 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1103 {CC "objectFieldOffset1", CC "(" CLS LANG "String;)J", FN_PTR(Unsafe_ObjectFieldOffset1)},
1104 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1105 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1106 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1107 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1108 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1109
1110 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1111 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1112 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1113 {CC "compareAndSetReference",CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSetReference)},
1114 {CC "compareAndSetInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSetInt)},
1115 {CC "compareAndSetLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSetLong)},
1116 {CC "compareAndExchangeReference", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeReference)},
1117 {CC "compareAndExchangeInt", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)},
1118 {CC "compareAndExchangeLong", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)},
1119
1120 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1121 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1122
1123 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1124
1125 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1126 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1127 {CC "writeback0", CC "(" "J" ")V", FN_PTR(Unsafe_WriteBack0)},
1128 {CC "writebackPreSync0", CC "()V", FN_PTR(Unsafe_WriteBackPreSync0)},
1129 {CC "writebackPostSync0", CC "()V", FN_PTR(Unsafe_WriteBackPostSync0)},
1130 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1131
1132 {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)},
1133
1134 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1135
1136 {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)},
1137 {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)},
1138 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1139 };
1140
1141 #undef CC
1142 #undef FN_PTR
1143
1144 #undef ADR
1145 #undef LANG
1146 #undef OBJ
1147 #undef CLS
1148 #undef FLD
1149 #undef THR
1150 #undef DC_Args
1151 #undef DAC_Args
1152
1153 #undef DECLARE_GETPUTOOP
1154
1155
1156 // This function is exported, used by NativeLookup.
1157 // The Unsafe_xxx functions above are called only from the interpreter.
1158 // The optimizer looks at names and signatures to recognize
1159 // individual functions.
1160
1161 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1162 ThreadToNativeFromVM ttnfv(thread);
1163
1164 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1165 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1166 } JVM_END