1 /*
2 * Copyright (c) 2000, 2019, 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/vmSymbols.hpp"
31 #include "jfr/jfrEvents.hpp"
32 #include "memory/allocation.inline.hpp"
33 #include "memory/resourceArea.hpp"
34 #include "oops/access.inline.hpp"
35 #include "oops/fieldStreams.inline.hpp"
36 #include "oops/objArrayOop.inline.hpp"
37 #include "oops/oop.inline.hpp"
38 #include "oops/typeArrayOop.inline.hpp"
39 #include "prims/unsafe.hpp"
40 #include "runtime/atomic.hpp"
41 #include "runtime/globals.hpp"
42 #include "runtime/handles.inline.hpp"
43 #include "runtime/interfaceSupport.inline.hpp"
44 #include "runtime/jniHandles.inline.hpp"
45 #include "runtime/orderAccess.hpp"
46 #include "runtime/reflection.hpp"
47 #include "runtime/sharedRuntime.hpp"
48 #include "runtime/thread.hpp"
49 #include "runtime/threadSMR.hpp"
50 #include "runtime/vm_version.hpp"
51 #include "services/threadService.hpp"
52 #include "utilities/align.hpp"
53 #include "utilities/copy.hpp"
54 #include "utilities/dtrace.hpp"
55 #include "utilities/macros.hpp"
56
57 /**
58 * Implementation of the jdk.internal.misc.Unsafe class
59 */
60
61
62 #define MAX_OBJECT_SIZE \
63 ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
64 + ((julong)max_jint * sizeof(double)) )
65
66
67 #define UNSAFE_ENTRY(result_type, header) \
68 JVM_ENTRY(static result_type, header)
69
70 #define UNSAFE_LEAF(result_type, header) \
71 JVM_LEAF(static result_type, header)
72
73 #define UNSAFE_END JVM_END
74
75
76 static inline void* addr_from_java(jlong addr) {
77 // This assert fails in a variety of ways on 32-bit systems.
78 // It is impossible to predict whether native code that converts
79 // pointers to longs will sign-extend or zero-extend the addresses.
80 //assert(addr == (uintptr_t)addr, "must not be odd high bits");
81 return (void*)(uintptr_t)addr;
82 }
83
84 static inline jlong addr_to_java(void* p) {
85 assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
86 return (uintptr_t)p;
87 }
88
89
90 // Note: The VM's obj_field and related accessors use byte-scaled
91 // ("unscaled") offsets, just as the unsafe methods do.
92
93 // However, the method Unsafe.fieldOffset explicitly declines to
94 // guarantee this. The field offset values manipulated by the Java user
95 // through the Unsafe API are opaque cookies that just happen to be byte
96 // offsets. We represent this state of affairs by passing the cookies
97 // through conversion functions when going between the VM and the Unsafe API.
98 // The conversion functions just happen to be no-ops at present.
99
100 static inline jlong field_offset_to_byte_offset(jlong field_offset) {
101 return field_offset;
102 }
103
104 static inline jlong field_offset_from_byte_offset(jlong byte_offset) {
105 return byte_offset;
106 }
107
108 static inline void assert_field_offset_sane(oop p, jlong field_offset) {
109 #ifdef ASSERT
110 jlong byte_offset = field_offset_to_byte_offset(field_offset);
111
112 if (p != NULL) {
113 assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
114 if (byte_offset == (jint)byte_offset) {
115 void* ptr_plus_disp = (address)p + byte_offset;
116 assert(p->field_addr_raw((jint)byte_offset) == ptr_plus_disp,
117 "raw [ptr+disp] must be consistent with oop::field_addr_raw");
118 }
119 jlong p_size = HeapWordSize * (jlong)(p->size());
120 assert(byte_offset < p_size, "Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, (int64_t)byte_offset, (int64_t)p_size);
121 }
122 #endif
123 }
124
125 static inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
126 assert_field_offset_sane(p, field_offset);
127 jlong byte_offset = field_offset_to_byte_offset(field_offset);
128
129 if (p != NULL) {
130 p = Access<>::resolve(p);
131 }
132
133 if (sizeof(char*) == sizeof(jint)) { // (this constant folds!)
134 return (address)p + (jint) byte_offset;
135 } else {
136 return (address)p + byte_offset;
137 }
138 }
139
140 // Externally callable versions:
141 // (Use these in compiler intrinsics which emulate unsafe primitives.)
142 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
143 return field_offset;
144 }
145 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
146 return byte_offset;
147 }
148
149
150 ///// Data read/writes on the Java heap and in native (off-heap) memory
151
152 /**
153 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access()
154 */
155 class GuardUnsafeAccess {
156 JavaThread* _thread;
157
158 public:
159 GuardUnsafeAccess(JavaThread* thread) : _thread(thread) {
160 // native/off-heap access which may raise SIGBUS if accessing
161 // memory mapped file data in a region of the file which has
162 // been truncated and is now invalid.
163 _thread->set_doing_unsafe_access(true);
164 }
165
166 ~GuardUnsafeAccess() {
167 _thread->set_doing_unsafe_access(false);
168 }
169 };
170
171 /**
172 * Helper class for accessing memory.
173 *
174 * Normalizes values and wraps accesses in
175 * JavaThread::doing_unsafe_access() if needed.
176 */
177 template <typename T>
178 class MemoryAccess : StackObj {
179 JavaThread* _thread;
180 oop _obj;
181 ptrdiff_t _offset;
182
183 // Resolves and returns the address of the memory access.
184 // This raw memory access may fault, so we make sure it happens within the
185 // guarded scope by making the access volatile at least. Since the store
186 // of Thread::set_doing_unsafe_access() is also volatile, these accesses
187 // can not be reordered by the compiler. Therefore, if the access triggers
188 // a fault, we will know that Thread::doing_unsafe_access() returns true.
189 volatile T* addr() {
190 void* addr = index_oop_from_field_offset_long(_obj, _offset);
191 return static_cast<volatile T*>(addr);
192 }
193
194 template <typename U>
195 U normalize_for_write(U x) {
196 return x;
197 }
198
199 jboolean normalize_for_write(jboolean x) {
200 return x & 1;
201 }
202
203 template <typename U>
204 U normalize_for_read(U x) {
205 return x;
206 }
207
208 jboolean normalize_for_read(jboolean x) {
209 return x != 0;
210 }
211
212 public:
213 MemoryAccess(JavaThread* thread, jobject obj, jlong offset)
214 : _thread(thread), _obj(JNIHandles::resolve(obj)), _offset((ptrdiff_t)offset) {
215 assert_field_offset_sane(_obj, offset);
216 }
217
218 T get() {
219 if (_obj == NULL) {
220 GuardUnsafeAccess guard(_thread);
221 T ret = RawAccess<>::load(addr());
222 return normalize_for_read(ret);
223 } else {
224 T ret = HeapAccess<>::load_at(_obj, _offset);
225 return normalize_for_read(ret);
226 }
227 }
228
229 void put(T x) {
230 if (_obj == NULL) {
231 GuardUnsafeAccess guard(_thread);
232 RawAccess<>::store(addr(), normalize_for_write(x));
233 } else {
234 HeapAccess<>::store_at(_obj, _offset, normalize_for_write(x));
235 }
236 }
237
238
239 T get_volatile() {
240 if (_obj == NULL) {
241 GuardUnsafeAccess guard(_thread);
242 volatile T ret = RawAccess<MO_SEQ_CST>::load(addr());
243 return normalize_for_read(ret);
244 } else {
245 T ret = HeapAccess<MO_SEQ_CST>::load_at(_obj, _offset);
246 return normalize_for_read(ret);
247 }
248 }
249
250 void put_volatile(T x) {
251 if (_obj == NULL) {
252 GuardUnsafeAccess guard(_thread);
253 RawAccess<MO_SEQ_CST>::store(addr(), normalize_for_write(x));
254 } else {
255 HeapAccess<MO_SEQ_CST>::store_at(_obj, _offset, normalize_for_write(x));
256 }
257 }
258 };
259
260 // These functions allow a null base pointer with an arbitrary address.
261 // But if the base pointer is non-null, the offset should make some sense.
262 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
263 UNSAFE_ENTRY(jobject, Unsafe_GetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
264 oop p = JNIHandles::resolve(obj);
265 assert_field_offset_sane(p, offset);
266 oop v = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
267 return JNIHandles::make_local(env, v);
268 } UNSAFE_END
269
270 UNSAFE_ENTRY(void, Unsafe_PutReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
271 oop x = JNIHandles::resolve(x_h);
272 oop p = JNIHandles::resolve(obj);
273 assert_field_offset_sane(p, offset);
274 HeapAccess<ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
275 } UNSAFE_END
276
277 UNSAFE_ENTRY(jobject, Unsafe_GetReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
278 oop p = JNIHandles::resolve(obj);
279 assert_field_offset_sane(p, offset);
280 oop v = HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
281 return JNIHandles::make_local(env, v);
282 } UNSAFE_END
283
284 UNSAFE_ENTRY(void, Unsafe_PutReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
285 oop x = JNIHandles::resolve(x_h);
286 oop p = JNIHandles::resolve(obj);
287 assert_field_offset_sane(p, offset);
288 HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
289 } UNSAFE_END
290
291 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) {
292 oop v = *(oop*) (address) addr;
293 return JNIHandles::make_local(env, v);
294 } UNSAFE_END
295
296 #define DEFINE_GETSETOOP(java_type, Type) \
297 \
298 UNSAFE_ENTRY(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
299 return MemoryAccess<java_type>(thread, obj, offset).get(); \
300 } UNSAFE_END \
301 \
302 UNSAFE_ENTRY(void, Unsafe_Put##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
303 MemoryAccess<java_type>(thread, obj, offset).put(x); \
304 } UNSAFE_END \
305 \
306 // END DEFINE_GETSETOOP.
307
308 DEFINE_GETSETOOP(jboolean, Boolean)
309 DEFINE_GETSETOOP(jbyte, Byte)
310 DEFINE_GETSETOOP(jshort, Short);
311 DEFINE_GETSETOOP(jchar, Char);
312 DEFINE_GETSETOOP(jint, Int);
313 DEFINE_GETSETOOP(jlong, Long);
314 DEFINE_GETSETOOP(jfloat, Float);
315 DEFINE_GETSETOOP(jdouble, Double);
316
317 #undef DEFINE_GETSETOOP
318
319 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \
320 \
321 UNSAFE_ENTRY(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
322 return MemoryAccess<java_type>(thread, obj, offset).get_volatile(); \
323 } UNSAFE_END \
324 \
325 UNSAFE_ENTRY(void, Unsafe_Put##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
326 MemoryAccess<java_type>(thread, obj, offset).put_volatile(x); \
327 } UNSAFE_END \
328 \
329 // END DEFINE_GETSETOOP_VOLATILE.
330
331 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
332 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
333 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
334 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
335 DEFINE_GETSETOOP_VOLATILE(jint, Int);
336 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
337 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
338 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
339
340 #undef DEFINE_GETSETOOP_VOLATILE
341
342 UNSAFE_LEAF(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe)) {
343 OrderAccess::acquire();
344 } UNSAFE_END
345
346 UNSAFE_LEAF(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe)) {
347 OrderAccess::release();
348 } UNSAFE_END
349
350 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
351 OrderAccess::fence();
352 } UNSAFE_END
353
354 ////// Allocation requests
355
356 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
357 ThreadToNativeFromVM ttnfv(thread);
358 return env->AllocObject(cls);
359 } UNSAFE_END
360
361 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) {
362 size_t sz = (size_t)size;
363
364 sz = align_up(sz, HeapWordSize);
365 void* x = os::malloc(sz, mtOther);
366
367 return addr_to_java(x);
368 } UNSAFE_END
369
370 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) {
371 void* p = addr_from_java(addr);
372 size_t sz = (size_t)size;
373 sz = align_up(sz, HeapWordSize);
374
375 void* x = os::realloc(p, sz, mtOther);
376
377 return addr_to_java(x);
378 } UNSAFE_END
379
380 UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) {
381 void* p = addr_from_java(addr);
382
383 os::free(p);
384 } UNSAFE_END
385
386 UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) {
387 size_t sz = (size_t)size;
388
389 oop base = JNIHandles::resolve(obj);
390 void* p = index_oop_from_field_offset_long(base, offset);
391
392 Copy::fill_to_memory_atomic(p, sz, value);
393 } UNSAFE_END
394
395 UNSAFE_ENTRY(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) {
396 size_t sz = (size_t)size;
397
398 oop srcp = JNIHandles::resolve(srcObj);
399 oop dstp = JNIHandles::resolve(dstObj);
400
401 void* src = index_oop_from_field_offset_long(srcp, srcOffset);
402 void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
403 {
404 GuardUnsafeAccess guard(thread);
405 if (StubRoutines::unsafe_arraycopy() != NULL) {
406 StubRoutines::UnsafeArrayCopy_stub()(src, dst, sz);
407 } else {
408 Copy::conjoint_memory_atomic(src, dst, sz);
409 }
410 }
411 } UNSAFE_END
412
413 // This function is a leaf since if the source and destination are both in native memory
414 // the copy may potentially be very large, and we don't want to disable GC if we can avoid it.
415 // If either source or destination (or both) are on the heap, the function will enter VM using
416 // JVM_ENTRY_FROM_LEAF
417 UNSAFE_LEAF(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) {
418 size_t sz = (size_t)size;
419 size_t esz = (size_t)elemSize;
420
421 if (srcObj == NULL && dstObj == NULL) {
422 // Both src & dst are in native memory
423 address src = (address)srcOffset;
424 address dst = (address)dstOffset;
425
426 {
427 JavaThread* thread = JavaThread::thread_from_jni_environment(env);
428 GuardUnsafeAccess guard(thread);
429 Copy::conjoint_swap(src, dst, sz, esz);
430 }
431 } else {
432 // At least one of src/dst are on heap, transition to VM to access raw pointers
433
434 JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) {
435 oop srcp = JNIHandles::resolve(srcObj);
436 oop dstp = JNIHandles::resolve(dstObj);
437
438 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset);
439 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset);
440
441 {
442 GuardUnsafeAccess guard(thread);
443 Copy::conjoint_swap(src, dst, sz, esz);
444 }
445 } JVM_END
446 }
447 } UNSAFE_END
448
449 UNSAFE_LEAF (void, Unsafe_WriteBack0(JNIEnv *env, jobject unsafe, jlong line)) {
450 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
451 #ifdef ASSERT
452 if (TraceMemoryWriteback) {
453 tty->print_cr("Unsafe: writeback 0x%p", addr_from_java(line));
454 }
455 #endif
456
457 assert(StubRoutines::data_cache_writeback() != NULL, "sanity");
458 (StubRoutines::DataCacheWriteback_stub())(addr_from_java(line));
459 } UNSAFE_END
460
461 static void doWriteBackSync0(bool is_pre)
462 {
463 assert(StubRoutines::data_cache_writeback_sync() != NULL, "sanity");
464 (StubRoutines::DataCacheWritebackSync_stub())(is_pre);
465 }
466
467 UNSAFE_LEAF (void, Unsafe_WriteBackPreSync0(JNIEnv *env, jobject unsafe)) {
468 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
469 #ifdef ASSERT
470 if (TraceMemoryWriteback) {
471 tty->print_cr("Unsafe: writeback pre-sync");
472 }
473 #endif
474
475 doWriteBackSync0(true);
476 } UNSAFE_END
477
478 UNSAFE_LEAF (void, Unsafe_WriteBackPostSync0(JNIEnv *env, jobject unsafe)) {
479 assert(VM_Version::supports_data_cache_line_flush(), "should not get here");
480 #ifdef ASSERT
481 if (TraceMemoryWriteback) {
482 tty->print_cr("Unsafe: writeback pre-sync");
483 }
484 #endif
485
486 doWriteBackSync0(false);
487 } UNSAFE_END
488
489 ////// Random queries
490
491 static jlong find_field_offset(jclass clazz, jstring name, TRAPS) {
492 assert(clazz != NULL, "clazz must not be NULL");
493 assert(name != NULL, "name must not be NULL");
494
495 ResourceMark rm(THREAD);
496 char *utf_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
497
498 InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz)));
499
500 jint offset = -1;
501 for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
502 Symbol *name = fs.name();
503 if (name->equals(utf_name)) {
504 offset = fs.offset();
505 break;
506 }
507 }
508 if (offset < 0) {
509 THROW_0(vmSymbols::java_lang_InternalError());
510 }
511 return field_offset_from_byte_offset(offset);
512 }
513
514 static jlong find_field_offset(jobject field, int must_be_static, TRAPS) {
515 assert(field != NULL, "field must not be NULL");
516
517 oop reflected = JNIHandles::resolve_non_null(field);
518 oop mirror = java_lang_reflect_Field::clazz(reflected);
519 Klass* k = java_lang_Class::as_Klass(mirror);
520 int slot = java_lang_reflect_Field::slot(reflected);
521 int modifiers = java_lang_reflect_Field::modifiers(reflected);
522
523 if (must_be_static >= 0) {
524 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
525 if (must_be_static != really_is_static) {
526 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
527 }
528 }
529
530 int offset = InstanceKlass::cast(k)->field_offset(slot);
531 return field_offset_from_byte_offset(offset);
532 }
533
534 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
535 return find_field_offset(field, 0, THREAD);
536 } UNSAFE_END
537
538 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset1(JNIEnv *env, jobject unsafe, jclass c, jstring name)) {
539 return find_field_offset(c, name, THREAD);
540 } UNSAFE_END
541
542 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
543 return find_field_offset(field, 1, THREAD);
544 } UNSAFE_END
545
546 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) {
547 assert(field != NULL, "field must not be NULL");
548
549 // Note: In this VM implementation, a field address is always a short
550 // offset from the base of a a klass metaobject. Thus, the full dynamic
551 // range of the return type is never used. However, some implementations
552 // might put the static field inside an array shared by many classes,
553 // or even at a fixed address, in which case the address could be quite
554 // large. In that last case, this function would return NULL, since
555 // the address would operate alone, without any base pointer.
556
557 oop reflected = JNIHandles::resolve_non_null(field);
558 oop mirror = java_lang_reflect_Field::clazz(reflected);
559 int modifiers = java_lang_reflect_Field::modifiers(reflected);
560
561 if ((modifiers & JVM_ACC_STATIC) == 0) {
562 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
563 }
564
565 return JNIHandles::make_local(env, mirror);
566 } UNSAFE_END
567
568 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
569 assert(clazz != NULL, "clazz must not be NULL");
570
571 oop mirror = JNIHandles::resolve_non_null(clazz);
572
573 Klass* klass = java_lang_Class::as_Klass(mirror);
574 if (klass != NULL && klass->should_be_initialized()) {
575 InstanceKlass* k = InstanceKlass::cast(klass);
576 k->initialize(CHECK);
577 }
578 }
579 UNSAFE_END
580
581 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
582 assert(clazz != NULL, "clazz must not be NULL");
583
584 oop mirror = JNIHandles::resolve_non_null(clazz);
585 Klass* klass = java_lang_Class::as_Klass(mirror);
586
587 if (klass != NULL && klass->should_be_initialized()) {
588 return true;
589 }
590
591 return false;
592 }
593 UNSAFE_END
594
595 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) {
596 assert(clazz != NULL, "clazz must not be NULL");
597
598 oop mirror = JNIHandles::resolve_non_null(clazz);
599 Klass* k = java_lang_Class::as_Klass(mirror);
600
601 if (k == NULL || !k->is_array_klass()) {
602 THROW(vmSymbols::java_lang_InvalidClassException());
603 } else if (k->is_objArray_klass()) {
604 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
605 scale = heapOopSize;
606 } else if (k->is_typeArray_klass()) {
607 TypeArrayKlass* tak = TypeArrayKlass::cast(k);
608 base = tak->array_header_in_bytes();
609 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
610 scale = (1 << tak->log2_element_size());
611 } else {
612 ShouldNotReachHere();
613 }
614 }
615
616 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) {
617 int base = 0, scale = 0;
618 getBaseAndScale(base, scale, clazz, CHECK_0);
619
620 return field_offset_from_byte_offset(base);
621 } UNSAFE_END
622
623
624 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) {
625 int base = 0, scale = 0;
626 getBaseAndScale(base, scale, clazz, CHECK_0);
627
628 // This VM packs both fields and array elements down to the byte.
629 // But watch out: If this changes, so that array references for
630 // a given primitive type (say, T_BOOLEAN) use different memory units
631 // than fields, this method MUST return zero for such arrays.
632 // For example, the VM used to store sub-word sized fields in full
633 // words in the object layout, so that accessors like getByte(Object,int)
634 // did not really do what one might expect for arrays. Therefore,
635 // this function used to report a zero scale factor, so that the user
636 // would know not to attempt to access sub-word array elements.
637 // // Code for unpacked fields:
638 // if (scale < wordSize) return 0;
639
640 // The following allows for a pretty general fieldOffset cookie scheme,
641 // but requires it to be linear in byte offset.
642 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
643 } UNSAFE_END
644
645
646 static inline void throw_new(JNIEnv *env, const char *ename) {
647 jclass cls = env->FindClass(ename);
648 if (env->ExceptionCheck()) {
649 env->ExceptionClear();
650 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", ename);
651 return;
652 }
653
654 env->ThrowNew(cls, NULL);
655 }
656
657 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
658 // Code lifted from JDK 1.3 ClassLoader.c
659
660 jbyte *body;
661 char *utfName = NULL;
662 jclass result = 0;
663 char buf[128];
664
665 assert(data != NULL, "Class bytes must not be NULL");
666 assert(length >= 0, "length must not be negative: %d", length);
667
668 if (UsePerfData) {
669 ClassLoader::unsafe_defineClassCallCounter()->inc();
670 }
671
672 body = NEW_C_HEAP_ARRAY_RETURN_NULL(jbyte, length, mtInternal);
673 if (body == NULL) {
674 throw_new(env, "java/lang/OutOfMemoryError");
675 return 0;
676 }
677
678 env->GetByteArrayRegion(data, offset, length, body);
679 if (env->ExceptionOccurred()) {
680 goto free_body;
681 }
682
683 if (name != NULL) {
684 uint len = env->GetStringUTFLength(name);
685 int unicode_len = env->GetStringLength(name);
686
687 if (len >= sizeof(buf)) {
688 utfName = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len + 1, mtInternal);
689 if (utfName == NULL) {
690 throw_new(env, "java/lang/OutOfMemoryError");
691 goto free_body;
692 }
693 } else {
694 utfName = buf;
695 }
696
697 env->GetStringUTFRegion(name, 0, unicode_len, utfName);
698
699 for (uint i = 0; i < len; i++) {
700 if (utfName[i] == '.') utfName[i] = '/';
701 }
702 }
703
704 result = JVM_DefineClass(env, utfName, loader, body, length, pd);
705
706 if (utfName && utfName != buf) {
707 FREE_C_HEAP_ARRAY(char, utfName);
708 }
709
710 free_body:
711 FREE_C_HEAP_ARRAY(jbyte, body);
712 return result;
713 }
714
715
716 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) {
717 ThreadToNativeFromVM ttnfv(thread);
718
719 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
720 } UNSAFE_END
721
722
723 // define a class but do not make it known to the class loader or system dictionary
724 // - host_class: supplies context for linkage, access control, protection domain, and class loader
725 // if host_class is itself anonymous then it is replaced with its host class.
726 // - data: bytes of a class file, a raw memory address (length gives the number of bytes)
727 // - cp_patches: where non-null entries exist, they replace corresponding CP entries in data
728
729 // When you load an anonymous class U, it works as if you changed its name just before loading,
730 // to a name that you will never use again. Since the name is lost, no other class can directly
731 // link to any member of U. Just after U is loaded, the only way to use it is reflectively,
732 // through java.lang.Class methods like Class.newInstance.
733
734 // The package of an anonymous class must either match its host's class's package or be in the
735 // unnamed package. If it is in the unnamed package then it will be put in its host class's
736 // package.
737 //
738
739 // Access checks for linkage sites within U continue to follow the same rules as for named classes.
740 // An anonymous class also has special privileges to access any member of its host class.
741 // This is the main reason why this loading operation is unsafe. The purpose of this is to
742 // allow language implementations to simulate "open classes"; a host class in effect gets
743 // new code when an anonymous class is loaded alongside it. A less convenient but more
744 // standard way to do this is with reflection, which can also be set to ignore access
745 // restrictions.
746
747 // Access into an anonymous class is possible only through reflection. Therefore, there
748 // are no special access rules for calling into an anonymous class. The relaxed access
749 // rule for the host class is applied in the opposite direction: A host class reflectively
750 // access one of its anonymous classes.
751
752 // If you load the same bytecodes twice, you get two different classes. You can reload
753 // the same bytecodes with or without varying CP patches.
754
755 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
756 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
757 // The CONSTANT_Class entry for that name can be patched to refer directly to U1.
758
759 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as
760 // an outer class (so that U2 is an anonymous inner class of anonymous U1).
761 // It is not possible for a named class, or an older anonymous class, to refer by
762 // name (via its CP) to a newer anonymous class.
763
764 // CP patching may also be used to modify (i.e., hack) the names of methods, classes,
765 // or type descriptors used in the loaded anonymous class.
766
767 // Finally, CP patching may be used to introduce "live" objects into the constant pool,
768 // instead of "dead" strings. A compiled statement like println((Object)"hello") can
769 // be changed to println(greeting), where greeting is an arbitrary object created before
770 // the anonymous class is loaded. This is useful in dynamic languages, in which
771 // various kinds of metaobjects must be introduced as constants into bytecode.
772 // Note the cast (Object), which tells the verifier to expect an arbitrary object,
773 // not just a literal string. For such ldc instructions, the verifier uses the
774 // type Object instead of String, if the loaded constant is not in fact a String.
775
776 static InstanceKlass*
777 Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
778 jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
779 u1** temp_alloc,
780 TRAPS) {
781 assert(host_class != NULL, "host_class must not be NULL");
782 assert(data != NULL, "data must not be NULL");
783
784 if (UsePerfData) {
785 ClassLoader::unsafe_defineClassCallCounter()->inc();
786 }
787
788 jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
789 assert(length >= 0, "class_bytes_length must not be negative: %d", length);
790
791 int class_bytes_length = (int) length;
792
793 u1* class_bytes = NEW_C_HEAP_ARRAY_RETURN_NULL(u1, length, mtInternal);
794 if (class_bytes == NULL) {
795 THROW_0(vmSymbols::java_lang_OutOfMemoryError());
796 }
797
798 // caller responsible to free it:
799 *temp_alloc = class_bytes;
800
801 ArrayAccess<>::arraycopy_to_native(arrayOop(JNIHandles::resolve_non_null(data)), typeArrayOopDesc::element_offset<jbyte>(0),
802 reinterpret_cast<jbyte*>(class_bytes), length);
803
804 objArrayHandle cp_patches_h;
805 if (cp_patches_jh != NULL) {
806 oop p = JNIHandles::resolve_non_null(cp_patches_jh);
807 assert(p->is_objArray(), "cp_patches must be an object[]");
808 cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
809 }
810
811 const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class));
812
813 // Make sure it's the real host class, not another anonymous class.
814 while (host_klass != NULL && host_klass->is_instance_klass() &&
815 InstanceKlass::cast(host_klass)->is_unsafe_anonymous()) {
816 host_klass = InstanceKlass::cast(host_klass)->unsafe_anonymous_host();
817 }
818
819 // Primitive types have NULL Klass* fields in their java.lang.Class instances.
820 if (host_klass == NULL) {
821 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Host class is null");
822 }
823
824 assert(host_klass->is_instance_klass(), "Host class must be an instance class");
825
826 const char* host_source = host_klass->external_name();
827 Handle host_loader(THREAD, host_klass->class_loader());
828 Handle host_domain(THREAD, host_klass->protection_domain());
829
830 GrowableArray<Handle>* cp_patches = NULL;
831
832 if (cp_patches_h.not_null()) {
833 int alen = cp_patches_h->length();
834
835 for (int i = alen-1; i >= 0; i--) {
836 oop p = cp_patches_h->obj_at(i);
837 if (p != NULL) {
838 Handle patch(THREAD, p);
839
840 if (cp_patches == NULL) {
841 cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
842 }
843
844 cp_patches->at_put(i, patch);
845 }
846 }
847 }
848
849 ClassFileStream st(class_bytes, class_bytes_length, host_source, ClassFileStream::verify);
850
851 Symbol* no_class_name = NULL;
852 Klass* anonk = SystemDictionary::parse_stream(no_class_name,
853 host_loader,
854 host_domain,
855 &st,
856 InstanceKlass::cast(host_klass),
857 cp_patches,
858 CHECK_NULL);
859 if (anonk == NULL) {
860 return NULL;
861 }
862
863 return InstanceKlass::cast(anonk);
864 }
865
866 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) {
867 ResourceMark rm(THREAD);
868
869 jobject res_jh = NULL;
870 u1* temp_alloc = NULL;
871
872 InstanceKlass* anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data, cp_patches_jh, &temp_alloc, THREAD);
873 if (anon_klass != NULL) {
874 res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
875 }
876
877 // try/finally clause:
878 FREE_C_HEAP_ARRAY(u1, temp_alloc);
879
880 // The anonymous class loader data has been artificially been kept alive to
881 // this point. The mirror and any instances of this class have to keep
882 // it alive afterwards.
883 if (anon_klass != NULL) {
884 anon_klass->class_loader_data()->dec_keep_alive();
885 }
886
887 // let caller initialize it as needed...
888
889 return (jclass) res_jh;
890 } UNSAFE_END
891
892
893
894 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
895 ThreadToNativeFromVM ttnfv(thread);
896 env->Throw(thr);
897 } UNSAFE_END
898
899 // JSR166 ------------------------------------------------------------------
900
901 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
902 oop x = JNIHandles::resolve(x_h);
903 oop e = JNIHandles::resolve(e_h);
904 oop p = JNIHandles::resolve(obj);
905 assert_field_offset_sane(p, offset);
906 oop res = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
907 return JNIHandles::make_local(env, res);
908 } UNSAFE_END
909
910 UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
911 oop p = JNIHandles::resolve(obj);
912 if (p == NULL) {
913 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
914 return RawAccess<>::atomic_cmpxchg(x, addr, e);
915 } else {
916 assert_field_offset_sane(p, offset);
917 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
918 }
919 } UNSAFE_END
920
921 UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
922 oop p = JNIHandles::resolve(obj);
923 if (p == NULL) {
924 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
925 return RawAccess<>::atomic_cmpxchg(x, addr, e);
926 } else {
927 assert_field_offset_sane(p, offset);
928 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
929 }
930 } UNSAFE_END
931
932 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
933 oop x = JNIHandles::resolve(x_h);
934 oop e = JNIHandles::resolve(e_h);
935 oop p = JNIHandles::resolve(obj);
936 assert_field_offset_sane(p, offset);
937 oop ret = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
938 return ret == e;
939 } UNSAFE_END
940
941 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
942 oop p = JNIHandles::resolve(obj);
943 if (p == NULL) {
944 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
945 return RawAccess<>::atomic_cmpxchg(x, addr, e) == e;
946 } else {
947 assert_field_offset_sane(p, offset);
948 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e) == e;
949 }
950 } UNSAFE_END
951
952 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
953 oop p = JNIHandles::resolve(obj);
954 if (p == NULL) {
955 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
956 return RawAccess<>::atomic_cmpxchg(x, addr, e) == e;
957 } else {
958 assert_field_offset_sane(p, offset);
959 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e) == e;
960 }
961 } UNSAFE_END
962
963 static void post_thread_park_event(EventThreadPark* event, const oop obj, jlong timeout_nanos, jlong until_epoch_millis) {
964 assert(event != NULL, "invariant");
965 assert(event->should_commit(), "invariant");
966 event->set_parkedClass((obj != NULL) ? obj->klass() : NULL);
967 event->set_timeout(timeout_nanos);
968 event->set_until(until_epoch_millis);
969 event->set_address((obj != NULL) ? (u8)cast_from_oop<uintptr_t>(obj) : 0);
970 event->commit();
971 }
972
973 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
974 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
975 EventThreadPark event;
976
977 JavaThreadParkedState jtps(thread, time != 0);
978 thread->parker()->park(isAbsolute != 0, time);
979 if (event.should_commit()) {
980 const oop obj = thread->current_park_blocker();
981 if (time == 0) {
982 post_thread_park_event(&event, obj, min_jlong, min_jlong);
983 } else {
984 if (isAbsolute != 0) {
985 post_thread_park_event(&event, obj, min_jlong, time);
986 } else {
987 post_thread_park_event(&event, obj, time, min_jlong);
988 }
989 }
990 }
991 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
992 } UNSAFE_END
993
994 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
995 Parker* p = NULL;
996
997 if (jthread != NULL) {
998 ThreadsListHandle tlh;
999 JavaThread* thr = NULL;
1000 oop java_thread = NULL;
1001 (void) tlh.cv_internal_thread_to_JavaThread(jthread, &thr, &java_thread);
1002 if (java_thread != NULL) {
1003 // This is a valid oop.
1004 if (thr != NULL) {
1005 // The JavaThread is alive.
1006 p = thr->parker();
1007 }
1008 }
1009 } // ThreadsListHandle is destroyed here.
1010
1011 // 'p' points to type-stable-memory if non-NULL. If the target
1012 // thread terminates before we get here the new user of this
1013 // Parker will get a 'spurious' unpark - which is perfectly valid.
1014 if (p != NULL) {
1015 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
1016 p->unpark();
1017 }
1018 } UNSAFE_END
1019
1020 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
1021 const int max_nelem = 3;
1022 double la[max_nelem];
1023 jint ret;
1024
1025 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
1026 assert(a->is_typeArray(), "must be type array");
1027
1028 ret = os::loadavg(la, nelem);
1029 if (ret == -1) {
1030 return -1;
1031 }
1032
1033 // if successful, ret is the number of samples actually retrieved.
1034 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
1035 switch(ret) {
1036 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
1037 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
1038 case 1: a->double_at_put(0, (jdouble)la[0]); break;
1039 }
1040
1041 return ret;
1042 } UNSAFE_END
1043
1044
1045 /// JVM_RegisterUnsafeMethods
1046
1047 #define ADR "J"
1048
1049 #define LANG "Ljava/lang/"
1050
1051 #define OBJ LANG "Object;"
1052 #define CLS LANG "Class;"
1053 #define FLD LANG "reflect/Field;"
1054 #define THR LANG "Throwable;"
1055
1056 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
1057 #define DAC_Args CLS "[B[" OBJ
1058
1059 #define CC (char*) /*cast a literal from (const char*)*/
1060 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1061
1062 #define DECLARE_GETPUTOOP(Type, Desc) \
1063 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
1064 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \
1065 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
1066 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)}
1067
1068
1069 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1070 {CC "getReference", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetReference)},
1071 {CC "putReference", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReference)},
1072 {CC "getReferenceVolatile", CC "(" OBJ "J)" OBJ, FN_PTR(Unsafe_GetReferenceVolatile)},
1073 {CC "putReferenceVolatile", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReferenceVolatile)},
1074
1075 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1076
1077 DECLARE_GETPUTOOP(Boolean, Z),
1078 DECLARE_GETPUTOOP(Byte, B),
1079 DECLARE_GETPUTOOP(Short, S),
1080 DECLARE_GETPUTOOP(Char, C),
1081 DECLARE_GETPUTOOP(Int, I),
1082 DECLARE_GETPUTOOP(Long, J),
1083 DECLARE_GETPUTOOP(Float, F),
1084 DECLARE_GETPUTOOP(Double, D),
1085
1086 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1087 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1088 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1089
1090 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1091 {CC "objectFieldOffset1", CC "(" CLS LANG "String;)J", FN_PTR(Unsafe_ObjectFieldOffset1)},
1092 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1093 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1094 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1095 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1096 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1097
1098 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1099 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1100 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1101 {CC "compareAndSetReference",CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSetReference)},
1102 {CC "compareAndSetInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSetInt)},
1103 {CC "compareAndSetLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSetLong)},
1104 {CC "compareAndExchangeReference", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeReference)},
1105 {CC "compareAndExchangeInt", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)},
1106 {CC "compareAndExchangeLong", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)},
1107
1108 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1109 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1110
1111 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1112
1113 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1114 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1115 {CC "writeback0", CC "(" "J" ")V", FN_PTR(Unsafe_WriteBack0)},
1116 {CC "writebackPreSync0", CC "()V", FN_PTR(Unsafe_WriteBackPreSync0)},
1117 {CC "writebackPostSync0", CC "()V", FN_PTR(Unsafe_WriteBackPostSync0)},
1118 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1119
1120 {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)},
1121
1122 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1123
1124 {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)},
1125 {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)},
1126 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1127 };
1128
1129 #undef CC
1130 #undef FN_PTR
1131
1132 #undef ADR
1133 #undef LANG
1134 #undef OBJ
1135 #undef CLS
1136 #undef FLD
1137 #undef THR
1138 #undef DC_Args
1139 #undef DAC_Args
1140
1141 #undef DECLARE_GETPUTOOP
1142
1143
1144 // This function is exported, used by NativeLookup.
1145 // The Unsafe_xxx functions above are called only from the interpreter.
1146 // The optimizer looks at names and signatures to recognize
1147 // individual functions.
1148
1149 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1150 ThreadToNativeFromVM ttnfv(thread);
1151
1152 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1153 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1154 } JVM_END