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.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/thread.hpp"
48 #include "runtime/threadSMR.hpp"
49 #include "runtime/vm_version.hpp"
50 #include "services/threadService.hpp"
51 #include "utilities/align.hpp"
52 #include "utilities/copy.hpp"
53 #include "utilities/dtrace.hpp"
54 #include "utilities/macros.hpp"
55
56 /**
57 * Implementation of the jdk.internal.misc.Unsafe class
58 */
59
60
61 #define MAX_OBJECT_SIZE \
62 ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
63 + ((julong)max_jint * sizeof(double)) )
64
65
66 #define UNSAFE_ENTRY(result_type, header) \
67 JVM_ENTRY(static result_type, header)
68
69 #define UNSAFE_LEAF(result_type, header) \
70 JVM_LEAF(static result_type, header)
71
72 #define UNSAFE_END JVM_END
73
74
75 static inline void* addr_from_java(jlong addr) {
76 // This assert fails in a variety of ways on 32-bit systems.
77 // It is impossible to predict whether native code that converts
78 // pointers to longs will sign-extend or zero-extend the addresses.
79 //assert(addr == (uintptr_t)addr, "must not be odd high bits");
80 return (void*)(uintptr_t)addr;
81 }
82
83 static inline jlong addr_to_java(void* p) {
84 assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
85 return (uintptr_t)p;
86 }
87
88
89 // Note: The VM's obj_field and related accessors use byte-scaled
90 // ("unscaled") offsets, just as the unsafe methods do.
91
92 // However, the method Unsafe.fieldOffset explicitly declines to
93 // guarantee this. The field offset values manipulated by the Java user
94 // through the Unsafe API are opaque cookies that just happen to be byte
95 // offsets. We represent this state of affairs by passing the cookies
96 // through conversion functions when going between the VM and the Unsafe API.
97 // The conversion functions just happen to be no-ops at present.
98
99 static inline jlong field_offset_to_byte_offset(jlong field_offset) {
100 return field_offset;
101 }
102
103 static inline jlong field_offset_from_byte_offset(jlong byte_offset) {
104 return byte_offset;
105 }
106
107 static inline void assert_field_offset_sane(oop p, jlong field_offset) {
108 #ifdef ASSERT
109 jlong byte_offset = field_offset_to_byte_offset(field_offset);
110
111 if (p != NULL) {
112 assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
113 if (byte_offset == (jint)byte_offset) {
114 void* ptr_plus_disp = (address)p + byte_offset;
115 assert(p->field_addr_raw((jint)byte_offset) == ptr_plus_disp,
116 "raw [ptr+disp] must be consistent with oop::field_addr_raw");
117 }
118 jlong p_size = HeapWordSize * (jlong)(p->size());
119 assert(byte_offset < p_size, "Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, (int64_t)byte_offset, (int64_t)p_size);
120 }
121 #endif
122 }
123
124 static inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
125 assert_field_offset_sane(p, field_offset);
126 jlong byte_offset = field_offset_to_byte_offset(field_offset);
127
128 if (p != NULL) {
129 p = Access<>::resolve(p);
130 }
131
132 if (sizeof(char*) == sizeof(jint)) { // (this constant folds!)
133 return (address)p + (jint) byte_offset;
134 } else {
135 return (address)p + byte_offset;
136 }
137 }
138
139 // Externally callable versions:
140 // (Use these in compiler intrinsics which emulate unsafe primitives.)
141 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
142 return field_offset;
143 }
144 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
145 return byte_offset;
146 }
147
148
149 ///// Data read/writes on the Java heap and in native (off-heap) memory
150
151 /**
152 * Helper class for accessing memory.
153 *
154 * Normalizes values and wraps accesses in
155 * JavaThread::doing_unsafe_access() if needed.
156 */
157 template <typename T>
158 class MemoryAccess : StackObj {
159 JavaThread* _thread;
160 oop _obj;
161 ptrdiff_t _offset;
162
163 // Resolves and returns the address of the memory access.
164 // This raw memory access may fault, so we make sure it happens within the
165 // guarded scope by making the access volatile at least. Since the store
166 // of Thread::set_doing_unsafe_access() is also volatile, these accesses
167 // can not be reordered by the compiler. Therefore, if the access triggers
168 // a fault, we will know that Thread::doing_unsafe_access() returns true.
169 volatile T* addr() {
170 void* addr = index_oop_from_field_offset_long(_obj, _offset);
171 return static_cast<volatile T*>(addr);
172 }
173
174 template <typename U>
175 U normalize_for_write(U x) {
176 return x;
177 }
178
179 jboolean normalize_for_write(jboolean x) {
180 return x & 1;
181 }
182
183 template <typename U>
184 U normalize_for_read(U x) {
185 return x;
186 }
187
188 jboolean normalize_for_read(jboolean x) {
189 return x != 0;
190 }
191
192 /**
193 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access()
194 */
195 class GuardUnsafeAccess {
196 JavaThread* _thread;
197
198 public:
199 GuardUnsafeAccess(JavaThread* thread) : _thread(thread) {
200 // native/off-heap access which may raise SIGBUS if accessing
201 // memory mapped file data in a region of the file which has
202 // been truncated and is now invalid
203 _thread->set_doing_unsafe_access(true);
204 }
205
206 ~GuardUnsafeAccess() {
207 _thread->set_doing_unsafe_access(false);
208 }
209 };
210
211 public:
212 MemoryAccess(JavaThread* thread, jobject obj, jlong offset)
213 : _thread(thread), _obj(JNIHandles::resolve(obj)), _offset((ptrdiff_t)offset) {
214 assert_field_offset_sane(_obj, offset);
215 }
216
217 T get() {
218 if (_obj == NULL) {
219 GuardUnsafeAccess guard(_thread);
220 T ret = RawAccess<>::load(addr());
221 return normalize_for_read(ret);
222 } else {
223 T ret = HeapAccess<>::load_at(_obj, _offset);
224 return normalize_for_read(ret);
225 }
226 }
227
228 void put(T x) {
229 if (_obj == NULL) {
230 GuardUnsafeAccess guard(_thread);
231 RawAccess<>::store(addr(), normalize_for_write(x));
232 } else {
233 HeapAccess<>::store_at(_obj, _offset, normalize_for_write(x));
234 }
235 }
236
237
238 T get_volatile() {
239 if (_obj == NULL) {
240 GuardUnsafeAccess guard(_thread);
241 volatile T ret = RawAccess<MO_SEQ_CST>::load(addr());
242 return normalize_for_read(ret);
243 } else {
244 T ret = HeapAccess<MO_SEQ_CST>::load_at(_obj, _offset);
245 return normalize_for_read(ret);
246 }
247 }
248
249 void put_volatile(T x) {
250 if (_obj == NULL) {
251 GuardUnsafeAccess guard(_thread);
252 RawAccess<MO_SEQ_CST>::store(addr(), normalize_for_write(x));
253 } else {
254 HeapAccess<MO_SEQ_CST>::store_at(_obj, _offset, normalize_for_write(x));
255 }
256 }
257 };
258
259 // These functions allow a null base pointer with an arbitrary address.
260 // But if the base pointer is non-null, the offset should make some sense.
261 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
262 UNSAFE_ENTRY(jobject, Unsafe_GetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
263 oop p = JNIHandles::resolve(obj);
264 assert_field_offset_sane(p, offset);
265 oop v = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
266 return JNIHandles::make_local(env, v);
267 } UNSAFE_END
268
269 UNSAFE_ENTRY(void, Unsafe_PutReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
270 oop x = JNIHandles::resolve(x_h);
271 oop p = JNIHandles::resolve(obj);
272 assert_field_offset_sane(p, offset);
273 HeapAccess<ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
274 } UNSAFE_END
275
276 UNSAFE_ENTRY(jobject, Unsafe_GetReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
277 oop p = JNIHandles::resolve(obj);
278 assert_field_offset_sane(p, offset);
279 oop v = HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
280 return JNIHandles::make_local(env, v);
281 } UNSAFE_END
282
283 UNSAFE_ENTRY(void, Unsafe_PutReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
284 oop x = JNIHandles::resolve(x_h);
285 oop p = JNIHandles::resolve(obj);
286 assert_field_offset_sane(p, offset);
287 HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
288 } UNSAFE_END
289
290 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) {
291 oop v = *(oop*) (address) addr;
292 return JNIHandles::make_local(env, v);
293 } UNSAFE_END
294
295 UNSAFE_LEAF(jboolean, Unsafe_isBigEndian0(JNIEnv *env, jobject unsafe)) {
296 #ifdef VM_LITTLE_ENDIAN
297 return false;
298 #else
299 return true;
300 #endif
301 } UNSAFE_END
302
303 UNSAFE_LEAF(jint, Unsafe_unalignedAccess0(JNIEnv *env, jobject unsafe)) {
304 return UseUnalignedAccesses;
305 } UNSAFE_END
306
307 #define DEFINE_GETSETOOP(java_type, Type) \
308 \
309 UNSAFE_ENTRY(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
310 return MemoryAccess<java_type>(thread, obj, offset).get(); \
311 } UNSAFE_END \
312 \
313 UNSAFE_ENTRY(void, Unsafe_Put##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
314 MemoryAccess<java_type>(thread, obj, offset).put(x); \
315 } UNSAFE_END \
316 \
317 // END DEFINE_GETSETOOP.
318
319 DEFINE_GETSETOOP(jboolean, Boolean)
320 DEFINE_GETSETOOP(jbyte, Byte)
321 DEFINE_GETSETOOP(jshort, Short);
322 DEFINE_GETSETOOP(jchar, Char);
323 DEFINE_GETSETOOP(jint, Int);
324 DEFINE_GETSETOOP(jlong, Long);
325 DEFINE_GETSETOOP(jfloat, Float);
326 DEFINE_GETSETOOP(jdouble, Double);
327
328 #undef DEFINE_GETSETOOP
329
330 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \
331 \
332 UNSAFE_ENTRY(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
333 return MemoryAccess<java_type>(thread, obj, offset).get_volatile(); \
334 } UNSAFE_END \
335 \
336 UNSAFE_ENTRY(void, Unsafe_Put##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
337 MemoryAccess<java_type>(thread, obj, offset).put_volatile(x); \
338 } UNSAFE_END \
339 \
340 // END DEFINE_GETSETOOP_VOLATILE.
341
342 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
343 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
344 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
345 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
346 DEFINE_GETSETOOP_VOLATILE(jint, Int);
347 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
348 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
349 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
350
351 #undef DEFINE_GETSETOOP_VOLATILE
352
353 UNSAFE_LEAF(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe)) {
354 OrderAccess::acquire();
355 } UNSAFE_END
356
357 UNSAFE_LEAF(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe)) {
358 OrderAccess::release();
359 } UNSAFE_END
360
361 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
362 OrderAccess::fence();
363 } UNSAFE_END
364
365 ////// Allocation requests
366
367 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
368 ThreadToNativeFromVM ttnfv(thread);
369 return env->AllocObject(cls);
370 } UNSAFE_END
371
372 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) {
373 size_t sz = (size_t)size;
374
375 sz = align_up(sz, HeapWordSize);
376 void* x = os::malloc(sz, mtOther);
377
378 return addr_to_java(x);
379 } UNSAFE_END
380
381 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) {
382 void* p = addr_from_java(addr);
383 size_t sz = (size_t)size;
384 sz = align_up(sz, HeapWordSize);
385
386 void* x = os::realloc(p, sz, mtOther);
387
388 return addr_to_java(x);
389 } UNSAFE_END
390
391 UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) {
392 void* p = addr_from_java(addr);
393
394 os::free(p);
395 } UNSAFE_END
396
397 UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) {
398 size_t sz = (size_t)size;
399
400 oop base = JNIHandles::resolve(obj);
401 void* p = index_oop_from_field_offset_long(base, offset);
402
403 Copy::fill_to_memory_atomic(p, sz, value);
404 } UNSAFE_END
405
406 UNSAFE_ENTRY(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) {
407 size_t sz = (size_t)size;
408
409 oop srcp = JNIHandles::resolve(srcObj);
410 oop dstp = JNIHandles::resolve(dstObj);
411
412 void* src = index_oop_from_field_offset_long(srcp, srcOffset);
413 void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
414
415 Copy::conjoint_memory_atomic(src, dst, sz);
416 } UNSAFE_END
417
418 // This function is a leaf since if the source and destination are both in native memory
419 // the copy may potentially be very large, and we don't want to disable GC if we can avoid it.
420 // If either source or destination (or both) are on the heap, the function will enter VM using
421 // JVM_ENTRY_FROM_LEAF
422 UNSAFE_LEAF(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) {
423 size_t sz = (size_t)size;
424 size_t esz = (size_t)elemSize;
425
426 if (srcObj == NULL && dstObj == NULL) {
427 // Both src & dst are in native memory
428 address src = (address)srcOffset;
429 address dst = (address)dstOffset;
430
431 Copy::conjoint_swap(src, dst, sz, esz);
432 } else {
433 // At least one of src/dst are on heap, transition to VM to access raw pointers
434
435 JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) {
436 oop srcp = JNIHandles::resolve(srcObj);
437 oop dstp = JNIHandles::resolve(dstObj);
438
439 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset);
440 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset);
441
442 Copy::conjoint_swap(src, dst, sz, esz);
443 } JVM_END
444 }
445 } UNSAFE_END
446
447 ////// Random queries
448
449 UNSAFE_LEAF(jint, Unsafe_AddressSize0(JNIEnv *env, jobject unsafe)) {
450 return sizeof(void*);
451 } UNSAFE_END
452
453 UNSAFE_LEAF(jint, Unsafe_PageSize()) {
454 return os::vm_page_size();
455 } UNSAFE_END
456
457 static jlong find_field_offset(jclass clazz, jstring name, TRAPS) {
458 assert(clazz != NULL, "clazz must not be NULL");
459 assert(name != NULL, "name must not be NULL");
460
461 ResourceMark rm(THREAD);
462 char *utf_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
463
464 InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz)));
465
466 jint offset = -1;
467 for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
468 Symbol *name = fs.name();
469 if (name->equals(utf_name)) {
470 offset = fs.offset();
471 break;
472 }
473 }
474 if (offset < 0) {
475 THROW_0(vmSymbols::java_lang_InternalError());
476 }
477 return field_offset_from_byte_offset(offset);
478 }
479
480 static jlong find_field_offset(jobject field, int must_be_static, TRAPS) {
481 assert(field != NULL, "field must not be NULL");
482
483 oop reflected = JNIHandles::resolve_non_null(field);
484 oop mirror = java_lang_reflect_Field::clazz(reflected);
485 Klass* k = java_lang_Class::as_Klass(mirror);
486 int slot = java_lang_reflect_Field::slot(reflected);
487 int modifiers = java_lang_reflect_Field::modifiers(reflected);
488
489 if (must_be_static >= 0) {
490 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
491 if (must_be_static != really_is_static) {
492 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
493 }
494 }
495
496 int offset = InstanceKlass::cast(k)->field_offset(slot);
497 return field_offset_from_byte_offset(offset);
498 }
499
500 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
501 return find_field_offset(field, 0, THREAD);
502 } UNSAFE_END
503
504 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset1(JNIEnv *env, jobject unsafe, jclass c, jstring name)) {
505 return find_field_offset(c, name, THREAD);
506 } UNSAFE_END
507
508 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
509 return find_field_offset(field, 1, THREAD);
510 } UNSAFE_END
511
512 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) {
513 assert(field != NULL, "field must not be NULL");
514
515 // Note: In this VM implementation, a field address is always a short
516 // offset from the base of a a klass metaobject. Thus, the full dynamic
517 // range of the return type is never used. However, some implementations
518 // might put the static field inside an array shared by many classes,
519 // or even at a fixed address, in which case the address could be quite
520 // large. In that last case, this function would return NULL, since
521 // the address would operate alone, without any base pointer.
522
523 oop reflected = JNIHandles::resolve_non_null(field);
524 oop mirror = java_lang_reflect_Field::clazz(reflected);
525 int modifiers = java_lang_reflect_Field::modifiers(reflected);
526
527 if ((modifiers & JVM_ACC_STATIC) == 0) {
528 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
529 }
530
531 return JNIHandles::make_local(env, mirror);
532 } UNSAFE_END
533
534 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
535 assert(clazz != NULL, "clazz must not be NULL");
536
537 oop mirror = JNIHandles::resolve_non_null(clazz);
538
539 Klass* klass = java_lang_Class::as_Klass(mirror);
540 if (klass != NULL && klass->should_be_initialized()) {
541 InstanceKlass* k = InstanceKlass::cast(klass);
542 k->initialize(CHECK);
543 }
544 }
545 UNSAFE_END
546
547 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
548 assert(clazz != NULL, "clazz must not be NULL");
549
550 oop mirror = JNIHandles::resolve_non_null(clazz);
551 Klass* klass = java_lang_Class::as_Klass(mirror);
552
553 if (klass != NULL && klass->should_be_initialized()) {
554 return true;
555 }
556
557 return false;
558 }
559 UNSAFE_END
560
561 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) {
562 assert(clazz != NULL, "clazz must not be NULL");
563
564 oop mirror = JNIHandles::resolve_non_null(clazz);
565 Klass* k = java_lang_Class::as_Klass(mirror);
566
567 if (k == NULL || !k->is_array_klass()) {
568 THROW(vmSymbols::java_lang_InvalidClassException());
569 } else if (k->is_objArray_klass()) {
570 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
571 scale = heapOopSize;
572 } else if (k->is_typeArray_klass()) {
573 TypeArrayKlass* tak = TypeArrayKlass::cast(k);
574 base = tak->array_header_in_bytes();
575 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
576 scale = (1 << tak->log2_element_size());
577 } else {
578 ShouldNotReachHere();
579 }
580 }
581
582 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) {
583 int base = 0, scale = 0;
584 getBaseAndScale(base, scale, clazz, CHECK_0);
585
586 return field_offset_from_byte_offset(base);
587 } UNSAFE_END
588
589
590 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) {
591 int base = 0, scale = 0;
592 getBaseAndScale(base, scale, clazz, CHECK_0);
593
594 // This VM packs both fields and array elements down to the byte.
595 // But watch out: If this changes, so that array references for
596 // a given primitive type (say, T_BOOLEAN) use different memory units
597 // than fields, this method MUST return zero for such arrays.
598 // For example, the VM used to store sub-word sized fields in full
599 // words in the object layout, so that accessors like getByte(Object,int)
600 // did not really do what one might expect for arrays. Therefore,
601 // this function used to report a zero scale factor, so that the user
602 // would know not to attempt to access sub-word array elements.
603 // // Code for unpacked fields:
604 // if (scale < wordSize) return 0;
605
606 // The following allows for a pretty general fieldOffset cookie scheme,
607 // but requires it to be linear in byte offset.
608 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
609 } UNSAFE_END
610
611
612 static inline void throw_new(JNIEnv *env, const char *ename) {
613 jclass cls = env->FindClass(ename);
614 if (env->ExceptionCheck()) {
615 env->ExceptionClear();
616 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", ename);
617 return;
618 }
619
620 env->ThrowNew(cls, NULL);
621 }
622
623 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
624 // Code lifted from JDK 1.3 ClassLoader.c
625
626 jbyte *body;
627 char *utfName = NULL;
628 jclass result = 0;
629 char buf[128];
630
631 assert(data != NULL, "Class bytes must not be NULL");
632 assert(length >= 0, "length must not be negative: %d", length);
633
634 if (UsePerfData) {
635 ClassLoader::unsafe_defineClassCallCounter()->inc();
636 }
637
638 body = NEW_C_HEAP_ARRAY(jbyte, length, mtInternal);
639 if (body == NULL) {
640 throw_new(env, "java/lang/OutOfMemoryError");
641 return 0;
642 }
643
644 env->GetByteArrayRegion(data, offset, length, body);
645 if (env->ExceptionOccurred()) {
646 goto free_body;
647 }
648
649 if (name != NULL) {
650 uint len = env->GetStringUTFLength(name);
651 int unicode_len = env->GetStringLength(name);
652
653 if (len >= sizeof(buf)) {
654 utfName = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
655 if (utfName == NULL) {
656 throw_new(env, "java/lang/OutOfMemoryError");
657 goto free_body;
658 }
659 } else {
660 utfName = buf;
661 }
662
663 env->GetStringUTFRegion(name, 0, unicode_len, utfName);
664
665 for (uint i = 0; i < len; i++) {
666 if (utfName[i] == '.') utfName[i] = '/';
667 }
668 }
669
670 result = JVM_DefineClass(env, utfName, loader, body, length, pd);
671
672 if (utfName && utfName != buf) {
673 FREE_C_HEAP_ARRAY(char, utfName);
674 }
675
676 free_body:
677 FREE_C_HEAP_ARRAY(jbyte, body);
678 return result;
679 }
680
681
682 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) {
683 ThreadToNativeFromVM ttnfv(thread);
684
685 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
686 } UNSAFE_END
687
688
689 // define a class but do not make it known to the class loader or system dictionary
690 // - host_class: supplies context for linkage, access control, protection domain, and class loader
691 // if host_class is itself anonymous then it is replaced with its host class.
692 // - data: bytes of a class file, a raw memory address (length gives the number of bytes)
693 // - cp_patches: where non-null entries exist, they replace corresponding CP entries in data
694
695 // When you load an anonymous class U, it works as if you changed its name just before loading,
696 // to a name that you will never use again. Since the name is lost, no other class can directly
697 // link to any member of U. Just after U is loaded, the only way to use it is reflectively,
698 // through java.lang.Class methods like Class.newInstance.
699
700 // The package of an anonymous class must either match its host's class's package or be in the
701 // unnamed package. If it is in the unnamed package then it will be put in its host class's
702 // package.
703 //
704
705 // Access checks for linkage sites within U continue to follow the same rules as for named classes.
706 // An anonymous class also has special privileges to access any member of its host class.
707 // This is the main reason why this loading operation is unsafe. The purpose of this is to
708 // allow language implementations to simulate "open classes"; a host class in effect gets
709 // new code when an anonymous class is loaded alongside it. A less convenient but more
710 // standard way to do this is with reflection, which can also be set to ignore access
711 // restrictions.
712
713 // Access into an anonymous class is possible only through reflection. Therefore, there
714 // are no special access rules for calling into an anonymous class. The relaxed access
715 // rule for the host class is applied in the opposite direction: A host class reflectively
716 // access one of its anonymous classes.
717
718 // If you load the same bytecodes twice, you get two different classes. You can reload
719 // the same bytecodes with or without varying CP patches.
720
721 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
722 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
723 // The CONSTANT_Class entry for that name can be patched to refer directly to U1.
724
725 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as
726 // an outer class (so that U2 is an anonymous inner class of anonymous U1).
727 // It is not possible for a named class, or an older anonymous class, to refer by
728 // name (via its CP) to a newer anonymous class.
729
730 // CP patching may also be used to modify (i.e., hack) the names of methods, classes,
731 // or type descriptors used in the loaded anonymous class.
732
733 // Finally, CP patching may be used to introduce "live" objects into the constant pool,
734 // instead of "dead" strings. A compiled statement like println((Object)"hello") can
735 // be changed to println(greeting), where greeting is an arbitrary object created before
736 // the anonymous class is loaded. This is useful in dynamic languages, in which
737 // various kinds of metaobjects must be introduced as constants into bytecode.
738 // Note the cast (Object), which tells the verifier to expect an arbitrary object,
739 // not just a literal string. For such ldc instructions, the verifier uses the
740 // type Object instead of String, if the loaded constant is not in fact a String.
741
742 static InstanceKlass*
743 Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
744 jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
745 u1** temp_alloc,
746 TRAPS) {
747 assert(host_class != NULL, "host_class must not be NULL");
748 assert(data != NULL, "data must not be NULL");
749
750 if (UsePerfData) {
751 ClassLoader::unsafe_defineClassCallCounter()->inc();
752 }
753
754 jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
755 assert(length >= 0, "class_bytes_length must not be negative: %d", length);
756
757 int class_bytes_length = (int) length;
758
759 u1* class_bytes = NEW_C_HEAP_ARRAY(u1, length, mtInternal);
760 if (class_bytes == NULL) {
761 THROW_0(vmSymbols::java_lang_OutOfMemoryError());
762 }
763
764 // caller responsible to free it:
765 *temp_alloc = class_bytes;
766
767 ArrayAccess<>::arraycopy_to_native(arrayOop(JNIHandles::resolve_non_null(data)), typeArrayOopDesc::element_offset<jbyte>(0),
768 reinterpret_cast<jbyte*>(class_bytes), length);
769
770 objArrayHandle cp_patches_h;
771 if (cp_patches_jh != NULL) {
772 oop p = JNIHandles::resolve_non_null(cp_patches_jh);
773 assert(p->is_objArray(), "cp_patches must be an object[]");
774 cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
775 }
776
777 const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class));
778
779 // Make sure it's the real host class, not another anonymous class.
780 while (host_klass != NULL && host_klass->is_instance_klass() &&
781 InstanceKlass::cast(host_klass)->is_unsafe_anonymous()) {
782 host_klass = InstanceKlass::cast(host_klass)->unsafe_anonymous_host();
783 }
784
785 // Primitive types have NULL Klass* fields in their java.lang.Class instances.
786 if (host_klass == NULL) {
787 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Host class is null");
788 }
789
790 assert(host_klass->is_instance_klass(), "Host class must be an instance class");
791
792 const char* host_source = host_klass->external_name();
793 Handle host_loader(THREAD, host_klass->class_loader());
794 Handle host_domain(THREAD, host_klass->protection_domain());
795
796 GrowableArray<Handle>* cp_patches = NULL;
797
798 if (cp_patches_h.not_null()) {
799 int alen = cp_patches_h->length();
800
801 for (int i = alen-1; i >= 0; i--) {
802 oop p = cp_patches_h->obj_at(i);
803 if (p != NULL) {
804 Handle patch(THREAD, p);
805
806 if (cp_patches == NULL) {
807 cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
808 }
809
810 cp_patches->at_put(i, patch);
811 }
812 }
813 }
814
815 ClassFileStream st(class_bytes, class_bytes_length, host_source, ClassFileStream::verify);
816
817 Symbol* no_class_name = NULL;
818 Klass* anonk = SystemDictionary::parse_stream(no_class_name,
819 host_loader,
820 host_domain,
821 &st,
822 InstanceKlass::cast(host_klass),
823 cp_patches,
824 CHECK_NULL);
825 if (anonk == NULL) {
826 return NULL;
827 }
828
829 return InstanceKlass::cast(anonk);
830 }
831
832 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) {
833 ResourceMark rm(THREAD);
834
835 jobject res_jh = NULL;
836 u1* temp_alloc = NULL;
837
838 InstanceKlass* anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data, cp_patches_jh, &temp_alloc, THREAD);
839 if (anon_klass != NULL) {
840 res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
841 }
842
843 // try/finally clause:
844 if (temp_alloc != NULL) {
845 FREE_C_HEAP_ARRAY(u1, temp_alloc);
846 }
847
848 // The anonymous class loader data has been artificially been kept alive to
849 // this point. The mirror and any instances of this class have to keep
850 // it alive afterwards.
851 if (anon_klass != NULL) {
852 anon_klass->class_loader_data()->dec_keep_alive();
853 }
854
855 // let caller initialize it as needed...
856
857 return (jclass) res_jh;
858 } UNSAFE_END
859
860
861
862 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
863 ThreadToNativeFromVM ttnfv(thread);
864 env->Throw(thr);
865 } UNSAFE_END
866
867 // JSR166 ------------------------------------------------------------------
868
869 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
870 oop x = JNIHandles::resolve(x_h);
871 oop e = JNIHandles::resolve(e_h);
872 oop p = JNIHandles::resolve(obj);
873 assert_field_offset_sane(p, offset);
874 oop res = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
875 return JNIHandles::make_local(env, res);
876 } UNSAFE_END
877
878 UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
879 oop p = JNIHandles::resolve(obj);
880 if (p == NULL) {
881 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
882 return RawAccess<>::atomic_cmpxchg(x, addr, e);
883 } else {
884 assert_field_offset_sane(p, offset);
885 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
886 }
887 } UNSAFE_END
888
889 UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
890 oop p = JNIHandles::resolve(obj);
891 if (p == NULL) {
892 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
893 return RawAccess<>::atomic_cmpxchg(x, addr, e);
894 } else {
895 assert_field_offset_sane(p, offset);
896 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
897 }
898 } UNSAFE_END
899
900 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
901 oop x = JNIHandles::resolve(x_h);
902 oop e = JNIHandles::resolve(e_h);
903 oop p = JNIHandles::resolve(obj);
904 assert_field_offset_sane(p, offset);
905 oop ret = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
906 return oopDesc::equals(ret, e);
907 } UNSAFE_END
908
909 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
910 oop p = JNIHandles::resolve(obj);
911 if (p == NULL) {
912 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
913 return RawAccess<>::atomic_cmpxchg(x, addr, e) == e;
914 } else {
915 assert_field_offset_sane(p, offset);
916 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e) == e;
917 }
918 } UNSAFE_END
919
920 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
921 oop p = JNIHandles::resolve(obj);
922 if (p == NULL) {
923 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
924 return RawAccess<>::atomic_cmpxchg(x, addr, e) == e;
925 } else {
926 assert_field_offset_sane(p, offset);
927 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e) == e;
928 }
929 } UNSAFE_END
930
931 static void post_thread_park_event(EventThreadPark* event, const oop obj, jlong timeout_nanos, jlong until_epoch_millis) {
932 assert(event != NULL, "invariant");
933 assert(event->should_commit(), "invariant");
934 event->set_parkedClass((obj != NULL) ? obj->klass() : NULL);
935 event->set_timeout(timeout_nanos);
936 event->set_until(until_epoch_millis);
937 event->set_address((obj != NULL) ? (u8)cast_from_oop<uintptr_t>(obj) : 0);
938 event->commit();
939 }
940
941 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
942 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
943 EventThreadPark event;
944
945 JavaThreadParkedState jtps(thread, time != 0);
946 thread->parker()->park(isAbsolute != 0, time);
947 if (event.should_commit()) {
948 const oop obj = thread->current_park_blocker();
949 if (time == 0) {
950 post_thread_park_event(&event, obj, min_jlong, min_jlong);
951 } else {
952 if (isAbsolute != 0) {
953 post_thread_park_event(&event, obj, min_jlong, time);
954 } else {
955 post_thread_park_event(&event, obj, time, min_jlong);
956 }
957 }
958 }
959 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
960 } UNSAFE_END
961
962 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
963 Parker* p = NULL;
964
965 if (jthread != NULL) {
966 ThreadsListHandle tlh;
967 JavaThread* thr = NULL;
968 oop java_thread = NULL;
969 (void) tlh.cv_internal_thread_to_JavaThread(jthread, &thr, &java_thread);
970 if (java_thread != NULL) {
971 // This is a valid oop.
972 jlong lp = java_lang_Thread::park_event(java_thread);
973 if (lp != 0) {
974 // This cast is OK even though the jlong might have been read
975 // non-atomically on 32bit systems, since there, one word will
976 // always be zero anyway and the value set is always the same
977 p = (Parker*)addr_from_java(lp);
978 } else {
979 // Not cached in the java.lang.Thread oop yet (could be an
980 // older version of library).
981 if (thr != NULL) {
982 // The JavaThread is alive.
983 p = thr->parker();
984 if (p != NULL) {
985 // Cache the Parker in the java.lang.Thread oop for next time.
986 java_lang_Thread::set_park_event(java_thread, addr_to_java(p));
987 }
988 }
989 }
990 }
991 } // ThreadsListHandle is destroyed here.
992
993 if (p != NULL) {
994 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
995 p->unpark();
996 }
997 } UNSAFE_END
998
999 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
1000 const int max_nelem = 3;
1001 double la[max_nelem];
1002 jint ret;
1003
1004 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
1005 assert(a->is_typeArray(), "must be type array");
1006
1007 ret = os::loadavg(la, nelem);
1008 if (ret == -1) {
1009 return -1;
1010 }
1011
1012 // if successful, ret is the number of samples actually retrieved.
1013 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
1014 switch(ret) {
1015 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
1016 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
1017 case 1: a->double_at_put(0, (jdouble)la[0]); break;
1018 }
1019
1020 return ret;
1021 } UNSAFE_END
1022
1023
1024 /// JVM_RegisterUnsafeMethods
1025
1026 #define ADR "J"
1027
1028 #define LANG "Ljava/lang/"
1029
1030 #define OBJ LANG "Object;"
1031 #define CLS LANG "Class;"
1032 #define FLD LANG "reflect/Field;"
1033 #define THR LANG "Throwable;"
1034
1035 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
1036 #define DAC_Args CLS "[B[" OBJ
1037
1038 #define CC (char*) /*cast a literal from (const char*)*/
1039 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1040
1041 #define DECLARE_GETPUTOOP(Type, Desc) \
1042 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
1043 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \
1044 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
1045 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)}
1046
1047
1048 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1049 {CC "getReference", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetReference)},
1050 {CC "putReference", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReference)},
1051 {CC "getReferenceVolatile", CC "(" OBJ "J)" OBJ, FN_PTR(Unsafe_GetReferenceVolatile)},
1052 {CC "putReferenceVolatile", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReferenceVolatile)},
1053
1054 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1055
1056 DECLARE_GETPUTOOP(Boolean, Z),
1057 DECLARE_GETPUTOOP(Byte, B),
1058 DECLARE_GETPUTOOP(Short, S),
1059 DECLARE_GETPUTOOP(Char, C),
1060 DECLARE_GETPUTOOP(Int, I),
1061 DECLARE_GETPUTOOP(Long, J),
1062 DECLARE_GETPUTOOP(Float, F),
1063 DECLARE_GETPUTOOP(Double, D),
1064
1065 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1066 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1067 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1068
1069 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1070 {CC "objectFieldOffset1", CC "(" CLS LANG "String;)J", FN_PTR(Unsafe_ObjectFieldOffset1)},
1071 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1072 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1073 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1074 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1075 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1076 {CC "addressSize0", CC "()I", FN_PTR(Unsafe_AddressSize0)},
1077 {CC "pageSize", CC "()I", FN_PTR(Unsafe_PageSize)},
1078
1079 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1080 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1081 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1082 {CC "compareAndSetReference",CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSetReference)},
1083 {CC "compareAndSetInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSetInt)},
1084 {CC "compareAndSetLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSetLong)},
1085 {CC "compareAndExchangeReference", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeReference)},
1086 {CC "compareAndExchangeInt", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)},
1087 {CC "compareAndExchangeLong", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)},
1088
1089 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1090 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1091
1092 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1093
1094 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1095 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1096 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1097
1098 {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)},
1099
1100 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1101
1102 {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)},
1103 {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)},
1104 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1105
1106 {CC "isBigEndian0", CC "()Z", FN_PTR(Unsafe_isBigEndian0)},
1107 {CC "unalignedAccess0", CC "()Z", FN_PTR(Unsafe_unalignedAccess0)}
1108 };
1109
1110 #undef CC
1111 #undef FN_PTR
1112
1113 #undef ADR
1114 #undef LANG
1115 #undef OBJ
1116 #undef CLS
1117 #undef FLD
1118 #undef THR
1119 #undef DC_Args
1120 #undef DAC_Args
1121
1122 #undef DECLARE_GETPUTOOP
1123
1124
1125 // This function is exported, used by NativeLookup.
1126 // The Unsafe_xxx functions above are called only from the interpreter.
1127 // The optimizer looks at names and signatures to recognize
1128 // individual functions.
1129
1130 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1131 ThreadToNativeFromVM ttnfv(thread);
1132
1133 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1134 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1135 } JVM_END