1 /*
2 * Copyright (c) 2000, 2016, 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 "classfile/classFileStream.hpp"
27 #include "classfile/vmSymbols.hpp"
28 #include "memory/allocation.inline.hpp"
29 #include "memory/resourceArea.hpp"
30 #include "oops/objArrayOop.inline.hpp"
31 #include "oops/oop.inline.hpp"
32 #include "prims/jni.h"
33 #include "prims/jvm.h"
34 #include "prims/unsafe.hpp"
35 #include "runtime/atomic.hpp"
36 #include "runtime/globals.hpp"
37 #include "runtime/interfaceSupport.hpp"
38 #include "runtime/orderAccess.inline.hpp"
39 #include "runtime/reflection.hpp"
40 #include "runtime/vm_version.hpp"
41 #include "services/threadService.hpp"
42 #include "trace/tracing.hpp"
43 #include "utilities/copy.hpp"
44 #include "utilities/dtrace.hpp"
45 #include "utilities/macros.hpp"
46 #if INCLUDE_ALL_GCS
47 #include "gc/g1/g1SATBCardTableModRefBS.hpp"
48 #endif // INCLUDE_ALL_GCS
49
50 /**
51 * Implementation of the jdk.internal.misc.Unsafe class
52 */
53
54
55 #define MAX_OBJECT_SIZE \
56 ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
57 + ((julong)max_jint * sizeof(double)) )
58
59
60 #define UNSAFE_ENTRY(result_type, header) \
61 JVM_ENTRY(static result_type, header)
62
63 #define UNSAFE_LEAF(result_type, header) \
64 JVM_LEAF(static result_type, header)
65
66 #define UNSAFE_END JVM_END
67
68
69 static inline void* addr_from_java(jlong addr) {
70 // This assert fails in a variety of ways on 32-bit systems.
71 // It is impossible to predict whether native code that converts
72 // pointers to longs will sign-extend or zero-extend the addresses.
73 //assert(addr == (uintptr_t)addr, "must not be odd high bits");
74 return (void*)(uintptr_t)addr;
75 }
76
77 static inline jlong addr_to_java(void* p) {
78 assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
79 return (uintptr_t)p;
80 }
81
82
83 // Note: The VM's obj_field and related accessors use byte-scaled
84 // ("unscaled") offsets, just as the unsafe methods do.
85
86 // However, the method Unsafe.fieldOffset explicitly declines to
87 // guarantee this. The field offset values manipulated by the Java user
88 // through the Unsafe API are opaque cookies that just happen to be byte
89 // offsets. We represent this state of affairs by passing the cookies
90 // through conversion functions when going between the VM and the Unsafe API.
91 // The conversion functions just happen to be no-ops at present.
92
93 static inline jlong field_offset_to_byte_offset(jlong field_offset) {
94 return field_offset;
95 }
96
97 static inline jlong field_offset_from_byte_offset(jlong byte_offset) {
98 return byte_offset;
99 }
100
101 static inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
102 jlong byte_offset = field_offset_to_byte_offset(field_offset);
103
104 #ifdef ASSERT
105 if (p != NULL) {
106 assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
107 if (byte_offset == (jint)byte_offset) {
108 void* ptr_plus_disp = (address)p + byte_offset;
109 assert((void*)p->obj_field_addr<oop>((jint)byte_offset) == ptr_plus_disp,
110 "raw [ptr+disp] must be consistent with oop::field_base");
111 }
112 jlong p_size = HeapWordSize * (jlong)(p->size());
113 assert(byte_offset < p_size, "Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, byte_offset, p_size);
114 }
115 #endif
116
117 if (sizeof(char*) == sizeof(jint)) { // (this constant folds!)
118 return (address)p + (jint) byte_offset;
119 } else {
120 return (address)p + byte_offset;
121 }
122 }
123
124 // Externally callable versions:
125 // (Use these in compiler intrinsics which emulate unsafe primitives.)
126 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
127 return field_offset;
128 }
129 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
130 return byte_offset;
131 }
132
133
134 ///// Data read/writes on the Java heap and in native (off-heap) memory
135
136 /**
137 * Helper class for accessing memory.
138 *
139 * Normalizes values and wraps accesses in
140 * JavaThread::doing_unsafe_access() if needed.
141 */
142 class MemoryAccess : StackObj {
143 JavaThread* _thread;
144 jobject _obj;
145 jlong _offset;
146
147 // Resolves and returns the address of the memory access
148 void* addr() {
149 return index_oop_from_field_offset_long(JNIHandles::resolve(_obj), _offset);
150 }
151
152 template <typename T>
153 T normalize_for_write(T x) {
154 return x;
155 }
156
157 jboolean normalize_for_write(jboolean x) {
158 return x & 1;
159 }
160
161 template <typename T>
162 T normalize_for_read(T x) {
163 return x;
164 }
165
166 jboolean normalize_for_read(jboolean x) {
167 return x != 0;
168 }
169
170 /**
171 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access()
172 */
173 class GuardUnsafeAccess {
174 JavaThread* _thread;
175 bool _active;
176
177 public:
178 GuardUnsafeAccess(JavaThread* thread, jobject _obj) : _thread(thread) {
179 if (JNIHandles::resolve(_obj) == NULL) {
180 // native/off-heap access which may raise SIGBUS if accessing
181 // memory mapped file data in a region of the file which has
182 // been truncated and is now invalid
183 _thread->set_doing_unsafe_access(true);
184 _active = true;
185 } else {
186 _active = false;
187 }
188 }
189
190 ~GuardUnsafeAccess() {
191 if (_active) {
192 _thread->set_doing_unsafe_access(false);
193 }
194 }
195 };
196
197 public:
198 MemoryAccess(JavaThread* thread, jobject obj, jlong offset)
199 : _thread(thread), _obj(obj), _offset(offset) {
200 }
201
202 template <typename T>
203 T get() {
204 GuardUnsafeAccess guard(_thread, _obj);
205
206 T* p = (T*)addr();
207
208 T x = normalize_for_read(*p);
209
210 return x;
211 }
212
213 template <typename T>
214 void put(T x) {
215 GuardUnsafeAccess guard(_thread, _obj);
216
217 T* p = (T*)addr();
218
219 *p = normalize_for_write(x);
220 }
221
222
223 template <typename T>
224 T get_volatile() {
225 GuardUnsafeAccess guard(_thread, _obj);
226
227 T* p = (T*)addr();
228
229 if (support_IRIW_for_not_multiple_copy_atomic_cpu) {
230 OrderAccess::fence();
231 }
232
233 T x = OrderAccess::load_acquire((volatile T*)p);
234
235 return normalize_for_read(x);
236 }
237
238 template <typename T>
239 void put_volatile(T x) {
240 GuardUnsafeAccess guard(_thread, _obj);
241
242 T* p = (T*)addr();
243
244 OrderAccess::release_store_fence((volatile T*)p, normalize_for_write(x));
245 }
246
247
248 #ifndef SUPPORTS_NATIVE_CX8
249 jlong get_jlong_locked() {
250 GuardUnsafeAccess guard(_thread, _obj);
251
252 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
253
254 jlong* p = (jlong*)addr();
255
256 jlong x = Atomic::load(p);
257
258 return x;
259 }
260
261 void put_jlong_locked(jlong x) {
262 GuardUnsafeAccess guard(_thread, _obj);
263
264 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
265
266 jlong* p = (jlong*)addr();
267
268 Atomic::store(normalize_for_write(x), p);
269 }
270 #endif
271 };
272
273 // Get/PutObject must be special-cased, since it works with handles.
274
275 // We could be accessing the referent field in a reference
276 // object. If G1 is enabled then we need to register non-null
277 // referent with the SATB barrier.
278
279 static bool is_java_lang_ref_Reference_access(oop o, jlong offset) {
280 if (offset == java_lang_ref_Reference::referent_offset && o != NULL) {
281 Klass* k = o->klass();
282 if (InstanceKlass::cast(k)->reference_type() != REF_NONE) {
283 assert(InstanceKlass::cast(k)->is_subclass_of(SystemDictionary::Reference_klass()), "sanity");
284 return true;
285 }
286 }
287 return false;
288 }
289
290 static void ensure_referent_alive(oop v) {
291 #if INCLUDE_ALL_GCS
292 if (UseG1GC && v != NULL) {
293 G1SATBCardTableModRefBS::enqueue(v);
294 }
295 #endif
296 }
297
298 // These functions allow a null base pointer with an arbitrary address.
299 // But if the base pointer is non-null, the offset should make some sense.
300 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
301 UNSAFE_ENTRY(jobject, Unsafe_GetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
302 oop p = JNIHandles::resolve(obj);
303 oop v;
304
305 if (UseCompressedOops) {
306 narrowOop n = *(narrowOop*)index_oop_from_field_offset_long(p, offset);
307 v = oopDesc::decode_heap_oop(n);
308 } else {
309 v = *(oop*)index_oop_from_field_offset_long(p, offset);
310 }
311
312 if (is_java_lang_ref_Reference_access(p, offset)) {
313 ensure_referent_alive(v);
314 }
315
316 return JNIHandles::make_local(env, v);
317 } UNSAFE_END
318
319 UNSAFE_ENTRY(void, Unsafe_PutObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
320 oop x = JNIHandles::resolve(x_h);
321 oop p = JNIHandles::resolve(obj);
322
323 if (UseCompressedOops) {
324 oop_store((narrowOop*)index_oop_from_field_offset_long(p, offset), x);
325 } else {
326 oop_store((oop*)index_oop_from_field_offset_long(p, offset), x);
327 }
328 } UNSAFE_END
329
330 UNSAFE_ENTRY(jobject, Unsafe_GetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
331 oop p = JNIHandles::resolve(obj);
332 void* addr = index_oop_from_field_offset_long(p, offset);
333
334 volatile oop v;
335
336 if (support_IRIW_for_not_multiple_copy_atomic_cpu) {
337 OrderAccess::fence();
338 }
339
340 if (UseCompressedOops) {
341 volatile narrowOop n = *(volatile narrowOop*) addr;
342 (void)const_cast<oop&>(v = oopDesc::decode_heap_oop(n));
343 } else {
344 (void)const_cast<oop&>(v = *(volatile oop*) addr);
345 }
346
347 if (is_java_lang_ref_Reference_access(p, offset)) {
348 ensure_referent_alive(v);
349 }
350
351 OrderAccess::acquire();
352 return JNIHandles::make_local(env, v);
353 } UNSAFE_END
354
355 UNSAFE_ENTRY(void, Unsafe_PutObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
356 oop x = JNIHandles::resolve(x_h);
357 oop p = JNIHandles::resolve(obj);
358 void* addr = index_oop_from_field_offset_long(p, offset);
359 OrderAccess::release();
360
361 if (UseCompressedOops) {
362 oop_store((narrowOop*)addr, x);
363 } else {
364 oop_store((oop*)addr, x);
365 }
366
367 OrderAccess::fence();
368 } UNSAFE_END
369
370 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) {
371 oop v = *(oop*) (address) addr;
372
373 return JNIHandles::make_local(env, v);
374 } UNSAFE_END
375
376 #ifndef SUPPORTS_NATIVE_CX8
377
378 // VM_Version::supports_cx8() is a surrogate for 'supports atomic long memory ops'.
379 //
380 // On platforms which do not support atomic compare-and-swap of jlong (8 byte)
381 // values we have to use a lock-based scheme to enforce atomicity. This has to be
382 // applied to all Unsafe operations that set the value of a jlong field. Even so
383 // the compareAndSwapLong operation will not be atomic with respect to direct stores
384 // to the field from Java code. It is important therefore that any Java code that
385 // utilizes these Unsafe jlong operations does not perform direct stores. To permit
386 // direct loads of the field from Java code we must also use Atomic::store within the
387 // locked regions. And for good measure, in case there are direct stores, we also
388 // employ Atomic::load within those regions. Note that the field in question must be
389 // volatile and so must have atomic load/store accesses applied at the Java level.
390 //
391 // The locking scheme could utilize a range of strategies for controlling the locking
392 // granularity: from a lock per-field through to a single global lock. The latter is
393 // the simplest and is used for the current implementation. Note that the Java object
394 // that contains the field, can not, in general, be used for locking. To do so can lead
395 // to deadlocks as we may introduce locking into what appears to the Java code to be a
396 // lock-free path.
397 //
398 // As all the locked-regions are very short and themselves non-blocking we can treat
399 // them as leaf routines and elide safepoint checks (ie we don't perform any thread
400 // state transitions even when blocking for the lock). Note that if we do choose to
401 // add safepoint checks and thread state transitions, we must ensure that we calculate
402 // the address of the field _after_ we have acquired the lock, else the object may have
403 // been moved by the GC
404
405 UNSAFE_ENTRY(jlong, Unsafe_GetLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
406 if (VM_Version::supports_cx8()) {
407 return MemoryAccess(thread, obj, offset).get_volatile<jlong>();
408 } else {
409 return MemoryAccess(thread, obj, offset).get_jlong_locked();
410 }
411 } UNSAFE_END
412
413 UNSAFE_ENTRY(void, Unsafe_PutLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong x)) {
414 if (VM_Version::supports_cx8()) {
415 MemoryAccess(thread, obj, offset).put_volatile<jlong>(x);
416 } else {
417 MemoryAccess(thread, obj, offset).put_jlong_locked(x);
418 }
419 } UNSAFE_END
420
421 #endif // not SUPPORTS_NATIVE_CX8
422
423 UNSAFE_LEAF(jboolean, Unsafe_isBigEndian0(JNIEnv *env, jobject unsafe)) {
424 #ifdef VM_LITTLE_ENDIAN
425 return false;
426 #else
427 return true;
428 #endif
429 } UNSAFE_END
430
431 UNSAFE_LEAF(jint, Unsafe_unalignedAccess0(JNIEnv *env, jobject unsafe)) {
432 return UseUnalignedAccesses;
433 } UNSAFE_END
434
435 #define DEFINE_GETSETOOP(java_type, Type) \
436 \
437 UNSAFE_ENTRY(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
438 return MemoryAccess(thread, obj, offset).get<java_type>(); \
439 } UNSAFE_END \
440 \
441 UNSAFE_ENTRY(void, Unsafe_Put##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
442 MemoryAccess(thread, obj, offset).put<java_type>(x); \
443 } UNSAFE_END \
444 \
445 // END DEFINE_GETSETOOP.
446
447 DEFINE_GETSETOOP(jboolean, Boolean)
448 DEFINE_GETSETOOP(jbyte, Byte)
449 DEFINE_GETSETOOP(jshort, Short);
450 DEFINE_GETSETOOP(jchar, Char);
451 DEFINE_GETSETOOP(jint, Int);
452 DEFINE_GETSETOOP(jlong, Long);
453 DEFINE_GETSETOOP(jfloat, Float);
454 DEFINE_GETSETOOP(jdouble, Double);
455
456 #undef DEFINE_GETSETOOP
457
458 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \
459 \
460 UNSAFE_ENTRY(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
461 return MemoryAccess(thread, obj, offset).get_volatile<java_type>(); \
462 } UNSAFE_END \
463 \
464 UNSAFE_ENTRY(void, Unsafe_Put##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
465 MemoryAccess(thread, obj, offset).put_volatile<java_type>(x); \
466 } UNSAFE_END \
467 \
468 // END DEFINE_GETSETOOP_VOLATILE.
469
470 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
471 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
472 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
473 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
474 DEFINE_GETSETOOP_VOLATILE(jint, Int);
475 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
476 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
477
478 #ifdef SUPPORTS_NATIVE_CX8
479 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
480 #endif
481
482 #undef DEFINE_GETSETOOP_VOLATILE
483
484 UNSAFE_LEAF(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe)) {
485 OrderAccess::acquire();
486 } UNSAFE_END
487
488 UNSAFE_LEAF(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe)) {
489 OrderAccess::release();
490 } UNSAFE_END
491
492 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
493 OrderAccess::fence();
494 } UNSAFE_END
495
496 ////// Allocation requests
497
498 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
499 ThreadToNativeFromVM ttnfv(thread);
500 return env->AllocObject(cls);
501 } UNSAFE_END
502
503 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) {
504 size_t sz = (size_t)size;
505
506 sz = round_to(sz, HeapWordSize);
507 void* x = os::malloc(sz, mtInternal);
508
509 return addr_to_java(x);
510 } UNSAFE_END
511
512 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) {
513 void* p = addr_from_java(addr);
514 size_t sz = (size_t)size;
515 sz = round_to(sz, HeapWordSize);
516
517 void* x = os::realloc(p, sz, mtInternal);
518
519 return addr_to_java(x);
520 } UNSAFE_END
521
522 UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) {
523 void* p = addr_from_java(addr);
524
525 os::free(p);
526 } UNSAFE_END
527
528 UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) {
529 size_t sz = (size_t)size;
530
531 oop base = JNIHandles::resolve(obj);
532 void* p = index_oop_from_field_offset_long(base, offset);
533
534 Copy::fill_to_memory_atomic(p, sz, value);
535 } UNSAFE_END
536
537 UNSAFE_ENTRY(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) {
538 size_t sz = (size_t)size;
539
540 oop srcp = JNIHandles::resolve(srcObj);
541 oop dstp = JNIHandles::resolve(dstObj);
542
543 void* src = index_oop_from_field_offset_long(srcp, srcOffset);
544 void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
545
546 Copy::conjoint_memory_atomic(src, dst, sz);
547 } UNSAFE_END
548
549 // This function is a leaf since if the source and destination are both in native memory
550 // the copy may potentially be very large, and we don't want to disable GC if we can avoid it.
551 // If either source or destination (or both) are on the heap, the function will enter VM using
552 // JVM_ENTRY_FROM_LEAF
553 UNSAFE_LEAF(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) {
554 size_t sz = (size_t)size;
555 size_t esz = (size_t)elemSize;
556
557 if (srcObj == NULL && dstObj == NULL) {
558 // Both src & dst are in native memory
559 address src = (address)srcOffset;
560 address dst = (address)dstOffset;
561
562 Copy::conjoint_swap(src, dst, sz, esz);
563 } else {
564 // At least one of src/dst are on heap, transition to VM to access raw pointers
565
566 JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) {
567 oop srcp = JNIHandles::resolve(srcObj);
568 oop dstp = JNIHandles::resolve(dstObj);
569
570 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset);
571 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset);
572
573 Copy::conjoint_swap(src, dst, sz, esz);
574 } JVM_END
575 }
576 } UNSAFE_END
577
578 ////// Random queries
579
580 UNSAFE_LEAF(jint, Unsafe_AddressSize0(JNIEnv *env, jobject unsafe)) {
581 return sizeof(void*);
582 } UNSAFE_END
583
584 UNSAFE_LEAF(jint, Unsafe_PageSize()) {
585 return os::vm_page_size();
586 } UNSAFE_END
587
588 static jint find_field_offset(jobject field, int must_be_static, TRAPS) {
589 assert(field != NULL, "field must not be NULL");
590
591 oop reflected = JNIHandles::resolve_non_null(field);
592 oop mirror = java_lang_reflect_Field::clazz(reflected);
593 Klass* k = java_lang_Class::as_Klass(mirror);
594 int slot = java_lang_reflect_Field::slot(reflected);
595 int modifiers = java_lang_reflect_Field::modifiers(reflected);
596
597 if (must_be_static >= 0) {
598 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
599 if (must_be_static != really_is_static) {
600 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
601 }
602 }
603
604 int offset = InstanceKlass::cast(k)->field_offset(slot);
605 return field_offset_from_byte_offset(offset);
606 }
607
608 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
609 return find_field_offset(field, 0, THREAD);
610 } UNSAFE_END
611
612 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
613 return find_field_offset(field, 1, THREAD);
614 } UNSAFE_END
615
616 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) {
617 assert(field != NULL, "field must not be NULL");
618
619 // Note: In this VM implementation, a field address is always a short
620 // offset from the base of a a klass metaobject. Thus, the full dynamic
621 // range of the return type is never used. However, some implementations
622 // might put the static field inside an array shared by many classes,
623 // or even at a fixed address, in which case the address could be quite
624 // large. In that last case, this function would return NULL, since
625 // the address would operate alone, without any base pointer.
626
627 oop reflected = JNIHandles::resolve_non_null(field);
628 oop mirror = java_lang_reflect_Field::clazz(reflected);
629 int modifiers = java_lang_reflect_Field::modifiers(reflected);
630
631 if ((modifiers & JVM_ACC_STATIC) == 0) {
632 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
633 }
634
635 return JNIHandles::make_local(env, mirror);
636 } UNSAFE_END
637
638 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
639 assert(clazz != NULL, "clazz must not be NULL");
640
641 oop mirror = JNIHandles::resolve_non_null(clazz);
642
643 Klass* klass = java_lang_Class::as_Klass(mirror);
644 if (klass != NULL && klass->should_be_initialized()) {
645 InstanceKlass* k = InstanceKlass::cast(klass);
646 k->initialize(CHECK);
647 }
648 }
649 UNSAFE_END
650
651 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
652 assert(clazz != NULL, "clazz must not be NULL");
653
654 oop mirror = JNIHandles::resolve_non_null(clazz);
655 Klass* klass = java_lang_Class::as_Klass(mirror);
656
657 if (klass != NULL && klass->should_be_initialized()) {
658 return true;
659 }
660
661 return false;
662 }
663 UNSAFE_END
664
665 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) {
666 assert(clazz != NULL, "clazz must not be NULL");
667
668 oop mirror = JNIHandles::resolve_non_null(clazz);
669 Klass* k = java_lang_Class::as_Klass(mirror);
670
671 if (k == NULL || !k->is_array_klass()) {
672 THROW(vmSymbols::java_lang_InvalidClassException());
673 } else if (k->is_objArray_klass()) {
674 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
675 scale = heapOopSize;
676 } else if (k->is_typeArray_klass()) {
677 TypeArrayKlass* tak = TypeArrayKlass::cast(k);
678 base = tak->array_header_in_bytes();
679 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
680 scale = (1 << tak->log2_element_size());
681 } else {
682 ShouldNotReachHere();
683 }
684 }
685
686 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) {
687 int base = 0, scale = 0;
688 getBaseAndScale(base, scale, clazz, CHECK_0);
689
690 return field_offset_from_byte_offset(base);
691 } UNSAFE_END
692
693
694 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) {
695 int base = 0, scale = 0;
696 getBaseAndScale(base, scale, clazz, CHECK_0);
697
698 // This VM packs both fields and array elements down to the byte.
699 // But watch out: If this changes, so that array references for
700 // a given primitive type (say, T_BOOLEAN) use different memory units
701 // than fields, this method MUST return zero for such arrays.
702 // For example, the VM used to store sub-word sized fields in full
703 // words in the object layout, so that accessors like getByte(Object,int)
704 // did not really do what one might expect for arrays. Therefore,
705 // this function used to report a zero scale factor, so that the user
706 // would know not to attempt to access sub-word array elements.
707 // // Code for unpacked fields:
708 // if (scale < wordSize) return 0;
709
710 // The following allows for a pretty general fieldOffset cookie scheme,
711 // but requires it to be linear in byte offset.
712 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
713 } UNSAFE_END
714
715
716 static inline void throw_new(JNIEnv *env, const char *ename) {
717 char buf[100];
718
719 jio_snprintf(buf, 100, "%s%s", "java/lang/", ename);
720
721 jclass cls = env->FindClass(buf);
722 if (env->ExceptionCheck()) {
723 env->ExceptionClear();
724 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", buf);
725 return;
726 }
727
728 env->ThrowNew(cls, NULL);
729 }
730
731 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
732 // Code lifted from JDK 1.3 ClassLoader.c
733
734 jbyte *body;
735 char *utfName = NULL;
736 jclass result = 0;
737 char buf[128];
738
739 assert(data != NULL, "Class bytes must not be NULL");
740 assert(length >= 0, "length must not be negative: %d", length);
741
742 if (UsePerfData) {
743 ClassLoader::unsafe_defineClassCallCounter()->inc();
744 }
745
746 body = NEW_C_HEAP_ARRAY(jbyte, length, mtInternal);
747 if (body == NULL) {
748 throw_new(env, "OutOfMemoryError");
749 return 0;
750 }
751
752 env->GetByteArrayRegion(data, offset, length, body);
753 if (env->ExceptionOccurred()) {
754 goto free_body;
755 }
756
757 if (name != NULL) {
758 uint len = env->GetStringUTFLength(name);
759 int unicode_len = env->GetStringLength(name);
760
761 if (len >= sizeof(buf)) {
762 utfName = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
763 if (utfName == NULL) {
764 throw_new(env, "OutOfMemoryError");
765 goto free_body;
766 }
767 } else {
768 utfName = buf;
769 }
770
771 env->GetStringUTFRegion(name, 0, unicode_len, utfName);
772
773 for (uint i = 0; i < len; i++) {
774 if (utfName[i] == '.') utfName[i] = '/';
775 }
776 }
777
778 result = JVM_DefineClass(env, utfName, loader, body, length, pd);
779
780 if (utfName && utfName != buf) {
781 FREE_C_HEAP_ARRAY(char, utfName);
782 }
783
784 free_body:
785 FREE_C_HEAP_ARRAY(jbyte, body);
786 return result;
787 }
788
789
790 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) {
791 ThreadToNativeFromVM ttnfv(thread);
792
793 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
794 } UNSAFE_END
795
796
797 // define a class but do not make it known to the class loader or system dictionary
798 // - host_class: supplies context for linkage, access control, protection domain, and class loader
799 // if host_class is itself anonymous then it is replaced with its host class.
800 // - data: bytes of a class file, a raw memory address (length gives the number of bytes)
801 // - cp_patches: where non-null entries exist, they replace corresponding CP entries in data
802
803 // When you load an anonymous class U, it works as if you changed its name just before loading,
804 // to a name that you will never use again. Since the name is lost, no other class can directly
805 // link to any member of U. Just after U is loaded, the only way to use it is reflectively,
806 // through java.lang.Class methods like Class.newInstance.
807
808 // The package of an anonymous class must either match its host's class's package or be in the
809 // unnamed package. If it is in the unnamed package then it will be put in its host class's
810 // package.
811 //
812
813 // Access checks for linkage sites within U continue to follow the same rules as for named classes.
814 // An anonymous class also has special privileges to access any member of its host class.
815 // This is the main reason why this loading operation is unsafe. The purpose of this is to
816 // allow language implementations to simulate "open classes"; a host class in effect gets
817 // new code when an anonymous class is loaded alongside it. A less convenient but more
818 // standard way to do this is with reflection, which can also be set to ignore access
819 // restrictions.
820
821 // Access into an anonymous class is possible only through reflection. Therefore, there
822 // are no special access rules for calling into an anonymous class. The relaxed access
823 // rule for the host class is applied in the opposite direction: A host class reflectively
824 // access one of its anonymous classes.
825
826 // If you load the same bytecodes twice, you get two different classes. You can reload
827 // the same bytecodes with or without varying CP patches.
828
829 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
830 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
831 // The CONSTANT_Class entry for that name can be patched to refer directly to U1.
832
833 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as
834 // an outer class (so that U2 is an anonymous inner class of anonymous U1).
835 // It is not possible for a named class, or an older anonymous class, to refer by
836 // name (via its CP) to a newer anonymous class.
837
838 // CP patching may also be used to modify (i.e., hack) the names of methods, classes,
839 // or type descriptors used in the loaded anonymous class.
840
841 // Finally, CP patching may be used to introduce "live" objects into the constant pool,
842 // instead of "dead" strings. A compiled statement like println((Object)"hello") can
843 // be changed to println(greeting), where greeting is an arbitrary object created before
844 // the anonymous class is loaded. This is useful in dynamic languages, in which
845 // various kinds of metaobjects must be introduced as constants into bytecode.
846 // Note the cast (Object), which tells the verifier to expect an arbitrary object,
847 // not just a literal string. For such ldc instructions, the verifier uses the
848 // type Object instead of String, if the loaded constant is not in fact a String.
849
850 static instanceKlassHandle
851 Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
852 jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
853 u1** temp_alloc,
854 TRAPS) {
855 assert(host_class != NULL, "host_class must not be NULL");
856 assert(data != NULL, "data must not be NULL");
857
858 if (UsePerfData) {
859 ClassLoader::unsafe_defineClassCallCounter()->inc();
860 }
861
862 jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
863 assert(length >= 0, "class_bytes_length must not be negative: %d", length);
864
865 int class_bytes_length = (int) length;
866
867 u1* class_bytes = NEW_C_HEAP_ARRAY(u1, length, mtInternal);
868 if (class_bytes == NULL) {
869 THROW_0(vmSymbols::java_lang_OutOfMemoryError());
870 }
871
872 // caller responsible to free it:
873 *temp_alloc = class_bytes;
874
875 jbyte* array_base = typeArrayOop(JNIHandles::resolve_non_null(data))->byte_at_addr(0);
876 Copy::conjoint_jbytes(array_base, class_bytes, length);
877
878 objArrayHandle cp_patches_h;
879 if (cp_patches_jh != NULL) {
880 oop p = JNIHandles::resolve_non_null(cp_patches_jh);
881 assert(p->is_objArray(), "cp_patches must be an object[]");
882 cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
883 }
884
885 const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class));
886
887 // Make sure it's the real host class, not another anonymous class.
888 while (host_klass != NULL && host_klass->is_instance_klass() &&
889 InstanceKlass::cast(host_klass)->is_anonymous()) {
890 host_klass = InstanceKlass::cast(host_klass)->host_klass();
891 }
892
893 // Primitive types have NULL Klass* fields in their java.lang.Class instances.
894 if (host_klass == NULL) {
895 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Host class is null");
896 }
897
898 assert(host_klass->is_instance_klass(), "Host class must be an instance class");
899
900 const char* host_source = host_klass->external_name();
901 Handle host_loader(THREAD, host_klass->class_loader());
902 Handle host_domain(THREAD, host_klass->protection_domain());
903
904 GrowableArray<Handle>* cp_patches = NULL;
905
906 if (cp_patches_h.not_null()) {
907 int alen = cp_patches_h->length();
908
909 for (int i = alen-1; i >= 0; i--) {
910 oop p = cp_patches_h->obj_at(i);
911 if (p != NULL) {
912 Handle patch(THREAD, p);
913
914 if (cp_patches == NULL) {
915 cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
916 }
917
918 cp_patches->at_put(i, patch);
919 }
920 }
921 }
922
923 ClassFileStream st(class_bytes, class_bytes_length, host_source, ClassFileStream::verify);
924
925 Symbol* no_class_name = NULL;
926 Klass* anonk = SystemDictionary::parse_stream(no_class_name,
927 host_loader,
928 host_domain,
929 &st,
930 InstanceKlass::cast(host_klass),
931 cp_patches,
932 CHECK_NULL);
933 if (anonk == NULL) {
934 return NULL;
935 }
936
937 return instanceKlassHandle(THREAD, anonk);
938 }
939
940 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) {
941 ResourceMark rm(THREAD);
942
943 instanceKlassHandle anon_klass;
944 jobject res_jh = NULL;
945 u1* temp_alloc = NULL;
946
947 anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data, cp_patches_jh, &temp_alloc, THREAD);
948 if (anon_klass() != NULL) {
949 res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
950 }
951
952 // try/finally clause:
953 if (temp_alloc != NULL) {
954 FREE_C_HEAP_ARRAY(u1, temp_alloc);
955 }
956
957 // The anonymous class loader data has been artificially been kept alive to
958 // this point. The mirror and any instances of this class have to keep
959 // it alive afterwards.
960 if (anon_klass() != NULL) {
961 anon_klass->class_loader_data()->dec_keep_alive();
962 }
963
964 // let caller initialize it as needed...
965
966 return (jclass) res_jh;
967 } UNSAFE_END
968
969
970
971 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
972 ThreadToNativeFromVM ttnfv(thread);
973 env->Throw(thr);
974 } UNSAFE_END
975
976 // JSR166 ------------------------------------------------------------------
977
978 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
979 oop x = JNIHandles::resolve(x_h);
980 oop e = JNIHandles::resolve(e_h);
981 oop p = JNIHandles::resolve(obj);
982 HeapWord* addr = (HeapWord *)index_oop_from_field_offset_long(p, offset);
983 oop res = oopDesc::atomic_compare_exchange_oop(x, addr, e, true);
984 if (res == e) {
985 update_barrier_set((void*)addr, x);
986 }
987 return JNIHandles::make_local(env, res);
988 } UNSAFE_END
989
990 UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
991 oop p = JNIHandles::resolve(obj);
992 jint* addr = (jint *) index_oop_from_field_offset_long(p, offset);
993
994 return (jint)(Atomic::cmpxchg(x, addr, e));
995 } UNSAFE_END
996
997 UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
998 Handle p(THREAD, JNIHandles::resolve(obj));
999 jlong* addr = (jlong*)index_oop_from_field_offset_long(p(), offset);
1000
1001 #ifdef SUPPORTS_NATIVE_CX8
1002 return (jlong)(Atomic::cmpxchg(x, addr, e));
1003 #else
1004 if (VM_Version::supports_cx8()) {
1005 return (jlong)(Atomic::cmpxchg(x, addr, e));
1006 } else {
1007 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
1008
1009 jlong val = Atomic::load(addr);
1010 if (val == e) {
1011 Atomic::store(x, addr);
1012 }
1013 return val;
1014 }
1015 #endif
1016 } UNSAFE_END
1017
1018 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
1019 oop x = JNIHandles::resolve(x_h);
1020 oop e = JNIHandles::resolve(e_h);
1021 oop p = JNIHandles::resolve(obj);
1022 HeapWord* addr = (HeapWord *)index_oop_from_field_offset_long(p, offset);
1023 oop res = oopDesc::atomic_compare_exchange_oop(x, addr, e, true);
1024 if (res != e) {
1025 return false;
1026 }
1027
1028 update_barrier_set((void*)addr, x);
1029
1030 return true;
1031 } UNSAFE_END
1032
1033 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
1034 oop p = JNIHandles::resolve(obj);
1035 jint* addr = (jint *)index_oop_from_field_offset_long(p, offset);
1036
1037 return (jint)(Atomic::cmpxchg(x, addr, e)) == e;
1038 } UNSAFE_END
1039
1040 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
1041 Handle p(THREAD, JNIHandles::resolve(obj));
1042 jlong* addr = (jlong*)index_oop_from_field_offset_long(p(), offset);
1043
1044 #ifdef SUPPORTS_NATIVE_CX8
1045 return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
1046 #else
1047 if (VM_Version::supports_cx8()) {
1048 return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
1049 } else {
1050 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
1051
1052 jlong val = Atomic::load(addr);
1053 if (val != e) {
1054 return false;
1055 }
1056
1057 Atomic::store(x, addr);
1058 return true;
1059 }
1060 #endif
1061 } UNSAFE_END
1062
1063 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
1064 EventThreadPark event;
1065 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
1066
1067 JavaThreadParkedState jtps(thread, time != 0);
1068 thread->parker()->park(isAbsolute != 0, time);
1069
1070 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
1071
1072 if (event.should_commit()) {
1073 oop obj = thread->current_park_blocker();
1074 event.set_parkedClass((obj != NULL) ? obj->klass() : NULL);
1075 event.set_timeout(time);
1076 event.set_address((obj != NULL) ? (TYPE_ADDRESS) cast_from_oop<uintptr_t>(obj) : 0);
1077 event.commit();
1078 }
1079 } UNSAFE_END
1080
1081 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
1082 Parker* p = NULL;
1083
1084 if (jthread != NULL) {
1085 oop java_thread = JNIHandles::resolve_non_null(jthread);
1086 if (java_thread != NULL) {
1087 jlong lp = java_lang_Thread::park_event(java_thread);
1088 if (lp != 0) {
1089 // This cast is OK even though the jlong might have been read
1090 // non-atomically on 32bit systems, since there, one word will
1091 // always be zero anyway and the value set is always the same
1092 p = (Parker*)addr_from_java(lp);
1093 } else {
1094 // Grab lock if apparently null or using older version of library
1095 MutexLocker mu(Threads_lock);
1096 java_thread = JNIHandles::resolve_non_null(jthread);
1097
1098 if (java_thread != NULL) {
1099 JavaThread* thr = java_lang_Thread::thread(java_thread);
1100 if (thr != NULL) {
1101 p = thr->parker();
1102 if (p != NULL) { // Bind to Java thread for next time.
1103 java_lang_Thread::set_park_event(java_thread, addr_to_java(p));
1104 }
1105 }
1106 }
1107 }
1108 }
1109 }
1110
1111 if (p != NULL) {
1112 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
1113 p->unpark();
1114 }
1115 } UNSAFE_END
1116
1117 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
1118 const int max_nelem = 3;
1119 double la[max_nelem];
1120 jint ret;
1121
1122 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
1123 assert(a->is_typeArray(), "must be type array");
1124
1125 ret = os::loadavg(la, nelem);
1126 if (ret == -1) {
1127 return -1;
1128 }
1129
1130 // if successful, ret is the number of samples actually retrieved.
1131 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
1132 switch(ret) {
1133 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
1134 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
1135 case 1: a->double_at_put(0, (jdouble)la[0]); break;
1136 }
1137
1138 return ret;
1139 } UNSAFE_END
1140
1141
1142 /// JVM_RegisterUnsafeMethods
1143
1144 #define ADR "J"
1145
1146 #define LANG "Ljava/lang/"
1147
1148 #define OBJ LANG "Object;"
1149 #define CLS LANG "Class;"
1150 #define FLD LANG "reflect/Field;"
1151 #define THR LANG "Throwable;"
1152
1153 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
1154 #define DAC_Args CLS "[B[" OBJ
1155
1156 #define CC (char*) /*cast a literal from (const char*)*/
1157 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1158
1159 #define DECLARE_GETPUTOOP(Type, Desc) \
1160 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
1161 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \
1162 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
1163 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)}
1164
1165
1166 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1167 {CC "getObject", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObject)},
1168 {CC "putObject", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutObject)},
1169 {CC "getObjectVolatile",CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObjectVolatile)},
1170 {CC "putObjectVolatile",CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutObjectVolatile)},
1171
1172 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1173
1174 DECLARE_GETPUTOOP(Boolean, Z),
1175 DECLARE_GETPUTOOP(Byte, B),
1176 DECLARE_GETPUTOOP(Short, S),
1177 DECLARE_GETPUTOOP(Char, C),
1178 DECLARE_GETPUTOOP(Int, I),
1179 DECLARE_GETPUTOOP(Long, J),
1180 DECLARE_GETPUTOOP(Float, F),
1181 DECLARE_GETPUTOOP(Double, D),
1182
1183 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1184 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1185 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1186
1187 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1188 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1189 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1190 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1191 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1192 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1193 {CC "addressSize0", CC "()I", FN_PTR(Unsafe_AddressSize0)},
1194 {CC "pageSize", CC "()I", FN_PTR(Unsafe_PageSize)},
1195
1196 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1197 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1198 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1199 {CC "compareAndSwapObject", CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSwapObject)},
1200 {CC "compareAndSwapInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSwapInt)},
1201 {CC "compareAndSwapLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSwapLong)},
1202 {CC "compareAndExchangeObjectVolatile", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeObject)},
1203 {CC "compareAndExchangeIntVolatile", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)},
1204 {CC "compareAndExchangeLongVolatile", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)},
1205
1206 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1207 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1208
1209 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1210
1211 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1212 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1213 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1214
1215 {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)},
1216
1217 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1218
1219 {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)},
1220 {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)},
1221 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1222
1223 {CC "isBigEndian0", CC "()Z", FN_PTR(Unsafe_isBigEndian0)},
1224 {CC "unalignedAccess0", CC "()Z", FN_PTR(Unsafe_unalignedAccess0)}
1225 };
1226
1227 #undef CC
1228 #undef FN_PTR
1229
1230 #undef ADR
1231 #undef LANG
1232 #undef OBJ
1233 #undef CLS
1234 #undef FLD
1235 #undef THR
1236 #undef DC_Args
1237 #undef DAC_Args
1238
1239 #undef DECLARE_GETPUTOOP
1240
1241
1242 // This function is exported, used by NativeLookup.
1243 // The Unsafe_xxx functions above are called only from the interpreter.
1244 // The optimizer looks at names and signatures to recognize
1245 // individual functions.
1246
1247 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1248 ThreadToNativeFromVM ttnfv(thread);
1249
1250 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1251 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1252 } JVM_END