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