1 /*
2 * Copyright (c) 2000, 2018, 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/vmSymbols.hpp"
30 #include "jfr/jfrEvents.hpp"
31 #include "memory/allocation.inline.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "logging/log.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 "oops/valueArrayKlass.hpp"
40 #include "oops/valueArrayOop.hpp"
41 #include "oops/valueArrayOop.inline.hpp"
42 #include "prims/unsafe.hpp"
43 #include "runtime/atomic.hpp"
44 #include "runtime/globals.hpp"
45 #include "runtime/interfaceSupport.inline.hpp"
46 #include "runtime/jniHandles.inline.hpp"
47 #include "runtime/orderAccess.inline.hpp"
48 #include "runtime/reflection.hpp"
49 #include "runtime/thread.hpp"
50 #include "runtime/threadSMR.hpp"
51 #include "runtime/vm_version.hpp"
52 #include "services/threadService.hpp"
53 #include "utilities/align.hpp"
54 #include "utilities/copy.hpp"
55 #include "utilities/dtrace.hpp"
56 #include "utilities/macros.hpp"
57
58 /**
59 * Implementation of the jdk.internal.misc.Unsafe class
60 */
61
62
63 #define MAX_OBJECT_SIZE \
64 ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
65 + ((julong)max_jint * sizeof(double)) )
66
67
68 #define UNSAFE_ENTRY(result_type, header) \
69 JVM_ENTRY(static result_type, header)
70
71 #define UNSAFE_LEAF(result_type, header) \
72 JVM_LEAF(static result_type, header)
73
74 #define UNSAFE_END JVM_END
75
76
77 static inline void* addr_from_java(jlong addr) {
78 // This assert fails in a variety of ways on 32-bit systems.
79 // It is impossible to predict whether native code that converts
80 // pointers to longs will sign-extend or zero-extend the addresses.
81 //assert(addr == (uintptr_t)addr, "must not be odd high bits");
82 return (void*)(uintptr_t)addr;
83 }
84
85 static inline jlong addr_to_java(void* p) {
86 assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
87 return (uintptr_t)p;
88 }
89
90
91 // Note: The VM's obj_field and related accessors use byte-scaled
92 // ("unscaled") offsets, just as the unsafe methods do.
93
94 // However, the method Unsafe.fieldOffset explicitly declines to
95 // guarantee this. The field offset values manipulated by the Java user
96 // through the Unsafe API are opaque cookies that just happen to be byte
97 // offsets. We represent this state of affairs by passing the cookies
98 // through conversion functions when going between the VM and the Unsafe API.
99 // The conversion functions just happen to be no-ops at present.
100
101 static inline jlong field_offset_to_byte_offset(jlong field_offset) {
102 return field_offset;
103 }
104
105 static inline jlong field_offset_from_byte_offset(jlong byte_offset) {
106 return byte_offset;
107 }
108
109 static inline void assert_field_offset_sane(oop p, jlong field_offset) {
110 #ifdef ASSERT
111 jlong byte_offset = field_offset_to_byte_offset(field_offset);
112
113 if (p != NULL) {
114 assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
115 if (byte_offset == (jint)byte_offset) {
116 void* ptr_plus_disp = (address)p + byte_offset;
117 assert(p->field_addr_raw((jint)byte_offset) == ptr_plus_disp,
118 "raw [ptr+disp] must be consistent with oop::field_addr_raw");
119 }
120 jlong p_size = HeapWordSize * (jlong)(p->size());
121 assert(byte_offset < p_size, "Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, (int64_t)byte_offset, (int64_t)p_size);
122 }
123 #endif
124 }
125
126 static inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
127 assert_field_offset_sane(p, field_offset);
128 jlong byte_offset = field_offset_to_byte_offset(field_offset);
129
130 if (p != NULL) {
131 p = Access<>::resolve(p);
132 }
133
134 if (sizeof(char*) == sizeof(jint)) { // (this constant folds!)
135 return (address)p + (jint) byte_offset;
136 } else {
137 return (address)p + byte_offset;
138 }
139 }
140
141 // Externally callable versions:
142 // (Use these in compiler intrinsics which emulate unsafe primitives.)
143 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
144 return field_offset;
145 }
146 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
147 return byte_offset;
148 }
149
150
151 ///// Data read/writes on the Java heap and in native (off-heap) memory
152
153 /**
154 * Helper class for accessing memory.
155 *
156 * Normalizes values and wraps accesses in
157 * JavaThread::doing_unsafe_access() if needed.
158 */
159 template <typename T>
160 class MemoryAccess : StackObj {
161 JavaThread* _thread;
162 oop _obj;
163 ptrdiff_t _offset;
164
165 // Resolves and returns the address of the memory access.
166 // This raw memory access may fault, so we make sure it happens within the
167 // guarded scope by making the access volatile at least. Since the store
168 // of Thread::set_doing_unsafe_access() is also volatile, these accesses
169 // can not be reordered by the compiler. Therefore, if the access triggers
170 // a fault, we will know that Thread::doing_unsafe_access() returns true.
171 volatile T* addr() {
172 void* addr = index_oop_from_field_offset_long(_obj, _offset);
173 return static_cast<volatile T*>(addr);
174 }
175
176 template <typename U>
177 U normalize_for_write(U x) {
178 return x;
179 }
180
181 jboolean normalize_for_write(jboolean x) {
182 return x & 1;
183 }
184
185 template <typename U>
186 U normalize_for_read(U x) {
187 return x;
188 }
189
190 jboolean normalize_for_read(jboolean x) {
191 return x != 0;
192 }
193
194 /**
195 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access()
196 */
197 class GuardUnsafeAccess {
198 JavaThread* _thread;
199
200 public:
201 GuardUnsafeAccess(JavaThread* thread) : _thread(thread) {
202 // native/off-heap access which may raise SIGBUS if accessing
203 // memory mapped file data in a region of the file which has
204 // been truncated and is now invalid
205 _thread->set_doing_unsafe_access(true);
206 }
207
208 ~GuardUnsafeAccess() {
209 _thread->set_doing_unsafe_access(false);
210 }
211 };
212
213 public:
214 MemoryAccess(JavaThread* thread, jobject obj, jlong offset)
215 : _thread(thread), _obj(JNIHandles::resolve(obj)), _offset((ptrdiff_t)offset) {
216 assert_field_offset_sane(_obj, offset);
217 }
218
219 T get() {
220 if (_obj == NULL) {
221 GuardUnsafeAccess guard(_thread);
222 T ret = RawAccess<>::load(addr());
223 return normalize_for_read(ret);
224 } else {
225 T ret = HeapAccess<>::load_at(_obj, _offset);
226 return normalize_for_read(ret);
227 }
228 }
229
230 void put(T x) {
231 if (_obj == NULL) {
232 GuardUnsafeAccess guard(_thread);
233 RawAccess<>::store(addr(), normalize_for_write(x));
234 } else {
235 HeapAccess<>::store_at(_obj, _offset, normalize_for_write(x));
236 }
237 }
238
239
240 T get_volatile() {
241 if (_obj == NULL) {
242 GuardUnsafeAccess guard(_thread);
243 volatile T ret = RawAccess<MO_SEQ_CST>::load(addr());
244 return normalize_for_read(ret);
245 } else {
246 T ret = HeapAccess<MO_SEQ_CST>::load_at(_obj, _offset);
247 return normalize_for_read(ret);
248 }
249 }
250
251 void put_volatile(T x) {
252 if (_obj == NULL) {
253 GuardUnsafeAccess guard(_thread);
254 RawAccess<MO_SEQ_CST>::store(addr(), normalize_for_write(x));
255 } else {
256 HeapAccess<MO_SEQ_CST>::store_at(_obj, _offset, normalize_for_write(x));
257 }
258 }
259 };
260
261 #ifdef ASSERT
262 /*
263 * Get the field descriptor of the field of the given object at the given offset.
264 */
265 static bool get_field_descriptor(oop p, jlong offset, fieldDescriptor* fd) {
266 bool found = false;
267 Klass* k = p->klass();
268 if (k->is_instance_klass()) {
269 InstanceKlass* ik = InstanceKlass::cast(k);
270 found = ik->find_field_from_offset((int)offset, false, fd);
271 if (!found && ik->is_mirror_instance_klass()) {
272 Klass* k2 = java_lang_Class::as_Klass(p);
273 if (k2->is_instance_klass()) {
274 ik = InstanceKlass::cast(k2);
275 found = ik->find_field_from_offset((int)offset, true, fd);
276 }
277 }
278 }
279 return found;
280 }
281 #endif // ASSERT
282
283 // These functions allow a null base pointer with an arbitrary address.
284 // But if the base pointer is non-null, the offset should make some sense.
285 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
286 UNSAFE_ENTRY(jobject, Unsafe_GetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
287 oop p = JNIHandles::resolve(obj);
288 assert_field_offset_sane(p, offset);
289 oop v = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
290 return JNIHandles::make_local(env, v);
291 } UNSAFE_END
292
293 UNSAFE_ENTRY(void, Unsafe_PutObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
294 oop x = JNIHandles::resolve(x_h);
295 oop p = JNIHandles::resolve(obj);
296 assert_field_offset_sane(p, offset);
297 HeapAccess<ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
298 } UNSAFE_END
299
300 UNSAFE_ENTRY(jobject, Unsafe_GetValue(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jclass c)) {
301 oop p = JNIHandles::resolve(obj);
302 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(c));
303 ValueKlass* vk = ValueKlass::cast(k);
304
305 #ifdef ASSERT
306 assert_field_offset_sane(p, offset);
307 fieldDescriptor fd;
308 bool found = get_field_descriptor(p, offset, &fd);
309 assert(found, "value field not found");
310 assert(fd.is_flattened(), "field not flat");
311 #endif // ASSERT
312
313 if (log_is_enabled(Trace, valuetypes)) {
314 log_trace(valuetypes)("getValue: field type %s at offset " SIZE_FORMAT_HEX,
315 vk->external_name(), offset);
316 }
317
318 Handle p_h(THREAD, p);
319 bool in_heap;
320 oop v = vk->allocate_buffered_or_heap_instance(&in_heap, CHECK_NULL); // allocate instance
321 vk->initialize(CHECK_NULL); // If field is a default value, value class might not be initialized yet
322 vk->value_store(((char*)(oopDesc*)p_h()) + offset,
323 vk->data_for_oop(v),
324 in_heap, true);
325 return JNIHandles::make_local(env, v);
326 } UNSAFE_END
327
328 UNSAFE_ENTRY(void, Unsafe_PutValue(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jclass c, jobject value)) {
329 oop v = JNIHandles::resolve(value);
330 oop p = JNIHandles::resolve(obj);
331 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(c));
332 ValueKlass* vk = ValueKlass::cast(k);
333
334 #ifdef ASSERT
335 assert_field_offset_sane(p, offset);
336 fieldDescriptor fd;
337 bool found = get_field_descriptor(p, offset, &fd);
338 assert(found, "value field not found");
339 assert(fd.is_flattened(), "field not flat");
340 #endif // ASSERT
341
342 if (log_is_enabled(Trace, valuetypes)) {
343 log_trace(valuetypes)("putValue: field type %s at offset " SIZE_FORMAT_HEX,
344 vk->external_name(), offset);
345 }
346 vk->value_store(vk->data_for_oop(v),
347 ((char*)(oopDesc*)p) + offset, true, true);
348 } UNSAFE_END
349
350 UNSAFE_ENTRY(jobject, Unsafe_GetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
351 oop p = JNIHandles::resolve(obj);
352 assert_field_offset_sane(p, offset);
353 oop v = HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
354 return JNIHandles::make_local(env, v);
355 } UNSAFE_END
356
357 UNSAFE_ENTRY(void, Unsafe_PutObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
358 oop x = JNIHandles::resolve(x_h);
359 oop p = JNIHandles::resolve(obj);
360 assert_field_offset_sane(p, offset);
361 HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
362 } UNSAFE_END
363
364 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) {
365 oop v = *(oop*) (address) addr;
366 return JNIHandles::make_local(env, v);
367 } UNSAFE_END
368
369 UNSAFE_LEAF(jboolean, Unsafe_isBigEndian0(JNIEnv *env, jobject unsafe)) {
370 #ifdef VM_LITTLE_ENDIAN
371 return false;
372 #else
373 return true;
374 #endif
375 } UNSAFE_END
376
377 UNSAFE_LEAF(jint, Unsafe_unalignedAccess0(JNIEnv *env, jobject unsafe)) {
378 return UseUnalignedAccesses;
379 } UNSAFE_END
380
381 #define DEFINE_GETSETOOP(java_type, Type) \
382 \
383 UNSAFE_ENTRY(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
384 return MemoryAccess<java_type>(thread, obj, offset).get(); \
385 } UNSAFE_END \
386 \
387 UNSAFE_ENTRY(void, Unsafe_Put##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
388 MemoryAccess<java_type>(thread, obj, offset).put(x); \
389 } UNSAFE_END \
390 \
391 // END DEFINE_GETSETOOP.
392
393 DEFINE_GETSETOOP(jboolean, Boolean)
394 DEFINE_GETSETOOP(jbyte, Byte)
395 DEFINE_GETSETOOP(jshort, Short);
396 DEFINE_GETSETOOP(jchar, Char);
397 DEFINE_GETSETOOP(jint, Int);
398 DEFINE_GETSETOOP(jlong, Long);
399 DEFINE_GETSETOOP(jfloat, Float);
400 DEFINE_GETSETOOP(jdouble, Double);
401
402 #undef DEFINE_GETSETOOP
403
404 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \
405 \
406 UNSAFE_ENTRY(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
407 return MemoryAccess<java_type>(thread, obj, offset).get_volatile(); \
408 } UNSAFE_END \
409 \
410 UNSAFE_ENTRY(void, Unsafe_Put##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
411 MemoryAccess<java_type>(thread, obj, offset).put_volatile(x); \
412 } UNSAFE_END \
413 \
414 // END DEFINE_GETSETOOP_VOLATILE.
415
416 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
417 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
418 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
419 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
420 DEFINE_GETSETOOP_VOLATILE(jint, Int);
421 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
422 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
423 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
424
425 #undef DEFINE_GETSETOOP_VOLATILE
426
427 UNSAFE_LEAF(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe)) {
428 OrderAccess::acquire();
429 } UNSAFE_END
430
431 UNSAFE_LEAF(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe)) {
432 OrderAccess::release();
433 } UNSAFE_END
434
435 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
436 OrderAccess::fence();
437 } UNSAFE_END
438
439 ////// Allocation requests
440
441 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
442 ThreadToNativeFromVM ttnfv(thread);
443 return env->AllocObject(cls);
444 } UNSAFE_END
445
446 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) {
447 size_t sz = (size_t)size;
448
449 sz = align_up(sz, HeapWordSize);
450 void* x = os::malloc(sz, mtOther);
451
452 return addr_to_java(x);
453 } UNSAFE_END
454
455 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) {
456 void* p = addr_from_java(addr);
457 size_t sz = (size_t)size;
458 sz = align_up(sz, HeapWordSize);
459
460 void* x = os::realloc(p, sz, mtOther);
461
462 return addr_to_java(x);
463 } UNSAFE_END
464
465 UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) {
466 void* p = addr_from_java(addr);
467
468 os::free(p);
469 } UNSAFE_END
470
471 UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) {
472 size_t sz = (size_t)size;
473
474 oop base = JNIHandles::resolve(obj);
475 void* p = index_oop_from_field_offset_long(base, offset);
476
477 Copy::fill_to_memory_atomic(p, sz, value);
478 } UNSAFE_END
479
480 UNSAFE_ENTRY(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) {
481 size_t sz = (size_t)size;
482
483 oop srcp = JNIHandles::resolve(srcObj);
484 oop dstp = JNIHandles::resolve(dstObj);
485
486 void* src = index_oop_from_field_offset_long(srcp, srcOffset);
487 void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
488
489 Copy::conjoint_memory_atomic(src, dst, sz);
490 } UNSAFE_END
491
492 // This function is a leaf since if the source and destination are both in native memory
493 // the copy may potentially be very large, and we don't want to disable GC if we can avoid it.
494 // If either source or destination (or both) are on the heap, the function will enter VM using
495 // JVM_ENTRY_FROM_LEAF
496 UNSAFE_LEAF(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) {
497 size_t sz = (size_t)size;
498 size_t esz = (size_t)elemSize;
499
500 if (srcObj == NULL && dstObj == NULL) {
501 // Both src & dst are in native memory
502 address src = (address)srcOffset;
503 address dst = (address)dstOffset;
504
505 Copy::conjoint_swap(src, dst, sz, esz);
506 } else {
507 // At least one of src/dst are on heap, transition to VM to access raw pointers
508
509 JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) {
510 oop srcp = JNIHandles::resolve(srcObj);
511 oop dstp = JNIHandles::resolve(dstObj);
512
513 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset);
514 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset);
515
516 Copy::conjoint_swap(src, dst, sz, esz);
517 } JVM_END
518 }
519 } UNSAFE_END
520
521 ////// Random queries
522
523 UNSAFE_LEAF(jint, Unsafe_AddressSize0(JNIEnv *env, jobject unsafe)) {
524 return sizeof(void*);
525 } UNSAFE_END
526
527 UNSAFE_LEAF(jint, Unsafe_PageSize()) {
528 return os::vm_page_size();
529 } UNSAFE_END
530
531 static jlong find_field_offset(jclass clazz, jstring name, TRAPS) {
532 assert(clazz != NULL, "clazz must not be NULL");
533 assert(name != NULL, "name must not be NULL");
534
535 ResourceMark rm(THREAD);
536 char *utf_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
537
538 InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz)));
539
540 jint offset = -1;
541 for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
542 Symbol *name = fs.name();
543 if (name->equals(utf_name)) {
544 offset = fs.offset();
545 break;
546 }
547 }
548 if (offset < 0) {
549 THROW_0(vmSymbols::java_lang_InternalError());
550 }
551 return field_offset_from_byte_offset(offset);
552 }
553
554 static jlong find_field_offset(jobject field, int must_be_static, TRAPS) {
555 assert(field != NULL, "field must not be NULL");
556
557 oop reflected = JNIHandles::resolve_non_null(field);
558 oop mirror = java_lang_reflect_Field::clazz(reflected);
559 Klass* k = java_lang_Class::as_Klass(mirror);
560 int slot = java_lang_reflect_Field::slot(reflected);
561 int modifiers = java_lang_reflect_Field::modifiers(reflected);
562
563 if (must_be_static >= 0) {
564 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
565 if (must_be_static != really_is_static) {
566 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
567 }
568 }
569
570 int offset = InstanceKlass::cast(k)->field_offset(slot);
571 return field_offset_from_byte_offset(offset);
572 }
573
574 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
575 return find_field_offset(field, 0, THREAD);
576 } UNSAFE_END
577
578 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset1(JNIEnv *env, jobject unsafe, jclass c, jstring name)) {
579 return find_field_offset(c, name, THREAD);
580 } UNSAFE_END
581
582 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
583 return find_field_offset(field, 1, THREAD);
584 } UNSAFE_END
585
586 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) {
587 assert(field != NULL, "field must not be NULL");
588
589 // Note: In this VM implementation, a field address is always a short
590 // offset from the base of a a klass metaobject. Thus, the full dynamic
591 // range of the return type is never used. However, some implementations
592 // might put the static field inside an array shared by many classes,
593 // or even at a fixed address, in which case the address could be quite
594 // large. In that last case, this function would return NULL, since
595 // the address would operate alone, without any base pointer.
596
597 oop reflected = JNIHandles::resolve_non_null(field);
598 oop mirror = java_lang_reflect_Field::clazz(reflected);
599 int modifiers = java_lang_reflect_Field::modifiers(reflected);
600
601 if ((modifiers & JVM_ACC_STATIC) == 0) {
602 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
603 }
604
605 return JNIHandles::make_local(env, mirror);
606 } UNSAFE_END
607
608 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
609 assert(clazz != NULL, "clazz must not be NULL");
610
611 oop mirror = JNIHandles::resolve_non_null(clazz);
612
613 Klass* klass = java_lang_Class::as_Klass(mirror);
614 if (klass != NULL && klass->should_be_initialized()) {
615 InstanceKlass* k = InstanceKlass::cast(klass);
616 k->initialize(CHECK);
617 }
618 }
619 UNSAFE_END
620
621 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
622 assert(clazz != NULL, "clazz must not be NULL");
623
624 oop mirror = JNIHandles::resolve_non_null(clazz);
625 Klass* klass = java_lang_Class::as_Klass(mirror);
626
627 if (klass != NULL && klass->should_be_initialized()) {
628 return true;
629 }
630
631 return false;
632 }
633 UNSAFE_END
634
635 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) {
636 assert(clazz != NULL, "clazz must not be NULL");
637
638 oop mirror = JNIHandles::resolve_non_null(clazz);
639 Klass* k = java_lang_Class::as_Klass(mirror);
640
641 if (k == NULL || !k->is_array_klass()) {
642 THROW(vmSymbols::java_lang_InvalidClassException());
643 } else if (k->is_objArray_klass()) {
644 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
645 scale = heapOopSize;
646 } else if (k->is_typeArray_klass()) {
647 TypeArrayKlass* tak = TypeArrayKlass::cast(k);
648 base = tak->array_header_in_bytes();
649 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
650 scale = (1 << tak->log2_element_size());
651 } else {
652 ShouldNotReachHere();
653 }
654 }
655
656 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) {
657 int base = 0, scale = 0;
658 getBaseAndScale(base, scale, clazz, CHECK_0);
659
660 return field_offset_from_byte_offset(base);
661 } UNSAFE_END
662
663
664 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) {
665 int base = 0, scale = 0;
666 getBaseAndScale(base, scale, clazz, CHECK_0);
667
668 // This VM packs both fields and array elements down to the byte.
669 // But watch out: If this changes, so that array references for
670 // a given primitive type (say, T_BOOLEAN) use different memory units
671 // than fields, this method MUST return zero for such arrays.
672 // For example, the VM used to store sub-word sized fields in full
673 // words in the object layout, so that accessors like getByte(Object,int)
674 // did not really do what one might expect for arrays. Therefore,
675 // this function used to report a zero scale factor, so that the user
676 // would know not to attempt to access sub-word array elements.
677 // // Code for unpacked fields:
678 // if (scale < wordSize) return 0;
679
680 // The following allows for a pretty general fieldOffset cookie scheme,
681 // but requires it to be linear in byte offset.
682 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
683 } UNSAFE_END
684
685
686 static inline void throw_new(JNIEnv *env, const char *ename) {
687 jclass cls = env->FindClass(ename);
688 if (env->ExceptionCheck()) {
689 env->ExceptionClear();
690 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", ename);
691 return;
692 }
693
694 env->ThrowNew(cls, NULL);
695 }
696
697 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
698 // Code lifted from JDK 1.3 ClassLoader.c
699
700 jbyte *body;
701 char *utfName = NULL;
702 jclass result = 0;
703 char buf[128];
704
705 assert(data != NULL, "Class bytes must not be NULL");
706 assert(length >= 0, "length must not be negative: %d", length);
707
708 if (UsePerfData) {
709 ClassLoader::unsafe_defineClassCallCounter()->inc();
710 }
711
712 body = NEW_C_HEAP_ARRAY(jbyte, length, mtInternal);
713 if (body == NULL) {
714 throw_new(env, "java/lang/OutOfMemoryError");
715 return 0;
716 }
717
718 env->GetByteArrayRegion(data, offset, length, body);
719 if (env->ExceptionOccurred()) {
720 goto free_body;
721 }
722
723 if (name != NULL) {
724 uint len = env->GetStringUTFLength(name);
725 int unicode_len = env->GetStringLength(name);
726
727 if (len >= sizeof(buf)) {
728 utfName = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
729 if (utfName == NULL) {
730 throw_new(env, "java/lang/OutOfMemoryError");
731 goto free_body;
732 }
733 } else {
734 utfName = buf;
735 }
736
737 env->GetStringUTFRegion(name, 0, unicode_len, utfName);
738
739 for (uint i = 0; i < len; i++) {
740 if (utfName[i] == '.') utfName[i] = '/';
741 }
742 }
743
744 result = JVM_DefineClass(env, utfName, loader, body, length, pd);
745
746 if (utfName && utfName != buf) {
747 FREE_C_HEAP_ARRAY(char, utfName);
748 }
749
750 free_body:
751 FREE_C_HEAP_ARRAY(jbyte, body);
752 return result;
753 }
754
755
756 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) {
757 ThreadToNativeFromVM ttnfv(thread);
758
759 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
760 } UNSAFE_END
761
762
763 // define a class but do not make it known to the class loader or system dictionary
764 // - host_class: supplies context for linkage, access control, protection domain, and class loader
765 // if host_class is itself anonymous then it is replaced with its host class.
766 // - data: bytes of a class file, a raw memory address (length gives the number of bytes)
767 // - cp_patches: where non-null entries exist, they replace corresponding CP entries in data
768
769 // When you load an anonymous class U, it works as if you changed its name just before loading,
770 // to a name that you will never use again. Since the name is lost, no other class can directly
771 // link to any member of U. Just after U is loaded, the only way to use it is reflectively,
772 // through java.lang.Class methods like Class.newInstance.
773
774 // The package of an anonymous class must either match its host's class's package or be in the
775 // unnamed package. If it is in the unnamed package then it will be put in its host class's
776 // package.
777 //
778
779 // Access checks for linkage sites within U continue to follow the same rules as for named classes.
780 // An anonymous class also has special privileges to access any member of its host class.
781 // This is the main reason why this loading operation is unsafe. The purpose of this is to
782 // allow language implementations to simulate "open classes"; a host class in effect gets
783 // new code when an anonymous class is loaded alongside it. A less convenient but more
784 // standard way to do this is with reflection, which can also be set to ignore access
785 // restrictions.
786
787 // Access into an anonymous class is possible only through reflection. Therefore, there
788 // are no special access rules for calling into an anonymous class. The relaxed access
789 // rule for the host class is applied in the opposite direction: A host class reflectively
790 // access one of its anonymous classes.
791
792 // If you load the same bytecodes twice, you get two different classes. You can reload
793 // the same bytecodes with or without varying CP patches.
794
795 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
796 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
797 // The CONSTANT_Class entry for that name can be patched to refer directly to U1.
798
799 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as
800 // an outer class (so that U2 is an anonymous inner class of anonymous U1).
801 // It is not possible for a named class, or an older anonymous class, to refer by
802 // name (via its CP) to a newer anonymous class.
803
804 // CP patching may also be used to modify (i.e., hack) the names of methods, classes,
805 // or type descriptors used in the loaded anonymous class.
806
807 // Finally, CP patching may be used to introduce "live" objects into the constant pool,
808 // instead of "dead" strings. A compiled statement like println((Object)"hello") can
809 // be changed to println(greeting), where greeting is an arbitrary object created before
810 // the anonymous class is loaded. This is useful in dynamic languages, in which
811 // various kinds of metaobjects must be introduced as constants into bytecode.
812 // Note the cast (Object), which tells the verifier to expect an arbitrary object,
813 // not just a literal string. For such ldc instructions, the verifier uses the
814 // type Object instead of String, if the loaded constant is not in fact a String.
815
816 static InstanceKlass*
817 Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
818 jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
819 u1** temp_alloc,
820 TRAPS) {
821 assert(host_class != NULL, "host_class must not be NULL");
822 assert(data != NULL, "data must not be NULL");
823
824 if (UsePerfData) {
825 ClassLoader::unsafe_defineClassCallCounter()->inc();
826 }
827
828 jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
829 assert(length >= 0, "class_bytes_length must not be negative: %d", length);
830
831 int class_bytes_length = (int) length;
832
833 u1* class_bytes = NEW_C_HEAP_ARRAY(u1, length, mtInternal);
834 if (class_bytes == NULL) {
835 THROW_0(vmSymbols::java_lang_OutOfMemoryError());
836 }
837
838 // caller responsible to free it:
839 *temp_alloc = class_bytes;
840
841 jbyte* array_base = typeArrayOop(JNIHandles::resolve_non_null(data))->byte_at_addr(0);
842 Copy::conjoint_jbytes(array_base, class_bytes, length);
843
844 objArrayHandle cp_patches_h;
845 if (cp_patches_jh != NULL) {
846 oop p = JNIHandles::resolve_non_null(cp_patches_jh);
847 assert(p->is_objArray(), "cp_patches must be an object[]");
848 cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
849 }
850
851 const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class));
852
853 // Make sure it's the real host class, not another anonymous class.
854 while (host_klass != NULL && host_klass->is_instance_klass() &&
855 InstanceKlass::cast(host_klass)->is_anonymous()) {
856 host_klass = InstanceKlass::cast(host_klass)->host_klass();
857 }
858
859 // Primitive types have NULL Klass* fields in their java.lang.Class instances.
860 if (host_klass == NULL) {
861 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Host class is null");
862 }
863
864 assert(host_klass->is_instance_klass(), "Host class must be an instance class");
865
866 const char* host_source = host_klass->external_name();
867 Handle host_loader(THREAD, host_klass->class_loader());
868 Handle host_domain(THREAD, host_klass->protection_domain());
869
870 GrowableArray<Handle>* cp_patches = NULL;
871
872 if (cp_patches_h.not_null()) {
873 int alen = cp_patches_h->length();
874
875 for (int i = alen-1; i >= 0; i--) {
876 oop p = cp_patches_h->obj_at(i);
877 if (p != NULL) {
878 Handle patch(THREAD, p);
879
880 if (cp_patches == NULL) {
881 cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
882 }
883
884 cp_patches->at_put(i, patch);
885 }
886 }
887 }
888
889 ClassFileStream st(class_bytes, class_bytes_length, host_source, ClassFileStream::verify);
890
891 Symbol* no_class_name = NULL;
892 Klass* anonk = SystemDictionary::parse_stream(no_class_name,
893 host_loader,
894 host_domain,
895 &st,
896 InstanceKlass::cast(host_klass),
897 cp_patches,
898 CHECK_NULL);
899 if (anonk == NULL) {
900 return NULL;
901 }
902
903 return InstanceKlass::cast(anonk);
904 }
905
906 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) {
907 ResourceMark rm(THREAD);
908
909 jobject res_jh = NULL;
910 u1* temp_alloc = NULL;
911
912 InstanceKlass* anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data, cp_patches_jh, &temp_alloc, THREAD);
913 if (anon_klass != NULL) {
914 res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
915 }
916
917 // try/finally clause:
918 if (temp_alloc != NULL) {
919 FREE_C_HEAP_ARRAY(u1, temp_alloc);
920 }
921
922 // The anonymous class loader data has been artificially been kept alive to
923 // this point. The mirror and any instances of this class have to keep
924 // it alive afterwards.
925 if (anon_klass != NULL) {
926 anon_klass->class_loader_data()->dec_keep_alive();
927 }
928
929 // let caller initialize it as needed...
930
931 return (jclass) res_jh;
932 } UNSAFE_END
933
934
935
936 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
937 ThreadToNativeFromVM ttnfv(thread);
938 env->Throw(thr);
939 } UNSAFE_END
940
941 // JSR166 ------------------------------------------------------------------
942
943 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
944 oop x = JNIHandles::resolve(x_h);
945 oop e = JNIHandles::resolve(e_h);
946 oop p = JNIHandles::resolve(obj);
947 assert_field_offset_sane(p, offset);
948 oop res = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
949 return JNIHandles::make_local(env, res);
950 } UNSAFE_END
951
952 UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
953 oop p = JNIHandles::resolve(obj);
954 if (p == NULL) {
955 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
956 return RawAccess<>::atomic_cmpxchg(x, addr, e);
957 } else {
958 assert_field_offset_sane(p, offset);
959 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
960 }
961 } UNSAFE_END
962
963 UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
964 oop p = JNIHandles::resolve(obj);
965 if (p == NULL) {
966 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
967 return RawAccess<>::atomic_cmpxchg(x, addr, e);
968 } else {
969 assert_field_offset_sane(p, offset);
970 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
971 }
972 } UNSAFE_END
973
974 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
975 oop x = JNIHandles::resolve(x_h);
976 oop e = JNIHandles::resolve(e_h);
977 oop p = JNIHandles::resolve(obj);
978 assert_field_offset_sane(p, offset);
979 oop ret = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
980 return oopDesc::equals(ret, e);
981 } UNSAFE_END
982
983 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
984 oop p = JNIHandles::resolve(obj);
985 if (p == NULL) {
986 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
987 return RawAccess<>::atomic_cmpxchg(x, addr, e) == e;
988 } else {
989 assert_field_offset_sane(p, offset);
990 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e) == e;
991 }
992 } UNSAFE_END
993
994 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
995 oop p = JNIHandles::resolve(obj);
996 if (p == NULL) {
997 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
998 return RawAccess<>::atomic_cmpxchg(x, addr, e) == e;
999 } else {
1000 assert_field_offset_sane(p, offset);
1001 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e) == e;
1002 }
1003 } UNSAFE_END
1004
1005 static void post_thread_park_event(EventThreadPark* event, const oop obj, jlong timeout) {
1006 assert(event != NULL, "invariant");
1007 assert(event->should_commit(), "invariant");
1008 event->set_parkedClass((obj != NULL) ? obj->klass() : NULL);
1009 event->set_timeout(timeout);
1010 event->set_address((obj != NULL) ? (u8)cast_from_oop<uintptr_t>(obj) : 0);
1011 event->commit();
1012 }
1013
1014 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
1015 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
1016 EventThreadPark event;
1017
1018 JavaThreadParkedState jtps(thread, time != 0);
1019 thread->parker()->park(isAbsolute != 0, time);
1020 if (event.should_commit()) {
1021 post_thread_park_event(&event, thread->current_park_blocker(), time);
1022 }
1023 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
1024 } UNSAFE_END
1025
1026 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
1027 Parker* p = NULL;
1028
1029 if (jthread != NULL) {
1030 ThreadsListHandle tlh;
1031 JavaThread* thr = NULL;
1032 oop java_thread = NULL;
1033 (void) tlh.cv_internal_thread_to_JavaThread(jthread, &thr, &java_thread);
1034 if (java_thread != NULL) {
1035 // This is a valid oop.
1036 jlong lp = java_lang_Thread::park_event(java_thread);
1037 if (lp != 0) {
1038 // This cast is OK even though the jlong might have been read
1039 // non-atomically on 32bit systems, since there, one word will
1040 // always be zero anyway and the value set is always the same
1041 p = (Parker*)addr_from_java(lp);
1042 } else {
1043 // Not cached in the java.lang.Thread oop yet (could be an
1044 // older version of library).
1045 if (thr != NULL) {
1046 // The JavaThread is alive.
1047 p = thr->parker();
1048 if (p != NULL) {
1049 // Cache the Parker in the java.lang.Thread oop for next time.
1050 java_lang_Thread::set_park_event(java_thread, addr_to_java(p));
1051 }
1052 }
1053 }
1054 }
1055 } // ThreadsListHandle is destroyed here.
1056
1057 if (p != NULL) {
1058 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
1059 p->unpark();
1060 }
1061 } UNSAFE_END
1062
1063 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
1064 const int max_nelem = 3;
1065 double la[max_nelem];
1066 jint ret;
1067
1068 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
1069 assert(a->is_typeArray(), "must be type array");
1070
1071 ret = os::loadavg(la, nelem);
1072 if (ret == -1) {
1073 return -1;
1074 }
1075
1076 // if successful, ret is the number of samples actually retrieved.
1077 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
1078 switch(ret) {
1079 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
1080 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
1081 case 1: a->double_at_put(0, (jdouble)la[0]); break;
1082 }
1083
1084 return ret;
1085 } UNSAFE_END
1086
1087
1088 /// JVM_RegisterUnsafeMethods
1089
1090 #define ADR "J"
1091
1092 #define LANG "Ljava/lang/"
1093
1094 #define OBJ LANG "Object;"
1095 #define CLS LANG "Class;"
1096 #define FLD LANG "reflect/Field;"
1097 #define THR LANG "Throwable;"
1098
1099 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
1100 #define DAC_Args CLS "[B[" OBJ
1101
1102 #define CC (char*) /*cast a literal from (const char*)*/
1103 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1104
1105 #define DECLARE_GETPUTOOP(Type, Desc) \
1106 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
1107 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \
1108 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
1109 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)}
1110
1111
1112 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1113 {CC "getObject", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObject)},
1114 {CC "putObject", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutObject)},
1115 {CC "getObjectVolatile",CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObjectVolatile)},
1116 {CC "putObjectVolatile",CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutObjectVolatile)},
1117
1118 {CC "getValue", CC "(" OBJ "J" CLS ")" OBJ "", FN_PTR(Unsafe_GetValue)},
1119 {CC "putValue", CC "(" OBJ "J" CLS OBJ ")V", FN_PTR(Unsafe_PutValue)},
1120
1121 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1122
1123 DECLARE_GETPUTOOP(Boolean, Z),
1124 DECLARE_GETPUTOOP(Byte, B),
1125 DECLARE_GETPUTOOP(Short, S),
1126 DECLARE_GETPUTOOP(Char, C),
1127 DECLARE_GETPUTOOP(Int, I),
1128 DECLARE_GETPUTOOP(Long, J),
1129 DECLARE_GETPUTOOP(Float, F),
1130 DECLARE_GETPUTOOP(Double, D),
1131
1132 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1133 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1134 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1135
1136 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1137 {CC "objectFieldOffset1", CC "(" CLS LANG "String;)J", FN_PTR(Unsafe_ObjectFieldOffset1)},
1138 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1139 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1140 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1141 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1142 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1143 {CC "addressSize0", CC "()I", FN_PTR(Unsafe_AddressSize0)},
1144 {CC "pageSize", CC "()I", FN_PTR(Unsafe_PageSize)},
1145
1146 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1147 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1148 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1149 {CC "compareAndSetObject",CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSetObject)},
1150 {CC "compareAndSetInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSetInt)},
1151 {CC "compareAndSetLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSetLong)},
1152 {CC "compareAndExchangeObject", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeObject)},
1153 {CC "compareAndExchangeInt", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)},
1154 {CC "compareAndExchangeLong", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)},
1155
1156 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1157 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1158
1159 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1160
1161 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1162 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1163 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1164
1165 {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)},
1166
1167 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1168
1169 {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)},
1170 {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)},
1171 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1172
1173 {CC "isBigEndian0", CC "()Z", FN_PTR(Unsafe_isBigEndian0)},
1174 {CC "unalignedAccess0", CC "()Z", FN_PTR(Unsafe_unalignedAccess0)}
1175 };
1176
1177 #undef CC
1178 #undef FN_PTR
1179
1180 #undef ADR
1181 #undef LANG
1182 #undef OBJ
1183 #undef CLS
1184 #undef FLD
1185 #undef THR
1186 #undef DC_Args
1187 #undef DAC_Args
1188
1189 #undef DECLARE_GETPUTOOP
1190
1191
1192 // This function is exported, used by NativeLookup.
1193 // The Unsafe_xxx functions above are called only from the interpreter.
1194 // The optimizer looks at names and signatures to recognize
1195 // individual functions.
1196
1197 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1198 ThreadToNativeFromVM ttnfv(thread);
1199
1200 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1201 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1202 } JVM_END