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