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.inline.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(T x) {
154 return x;
155 }
156
157 jboolean normalize(jboolean x) {
158 return x & 1;
159 }
160
161 /**
162 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access()
163 */
164 class GuardUnsafeAccess {
165 JavaThread* _thread;
166 bool _active;
167
168 public:
169 GuardUnsafeAccess(JavaThread* thread, jobject _obj) : _thread(thread) {
170 if (JNIHandles::resolve(_obj) == NULL) {
171 // native/off-heap access which may raise SIGBUS if accessing
172 // memory mapped file data in a region of the file which has
173 // been truncated and is now invalid
174 _thread->set_doing_unsafe_access(true);
175 _active = true;
176 } else {
177 _active = false;
178 }
179 }
180
181 ~GuardUnsafeAccess() {
182 if (_active) {
183 _thread->set_doing_unsafe_access(false);
184 }
185 }
186 };
187
188 public:
189 MemoryAccess(JavaThread* thread, jobject obj, jlong offset)
190 : _thread(thread), _obj(obj), _offset(offset) {
191 }
192
193 template <typename T>
194 T get() {
195 GuardUnsafeAccess guard(_thread, _obj);
196
197 T* p = (T*)addr();
198
199 T x = *p;
200
201 return x;
202 }
203
204 template <typename T>
205 void put(T x) {
206 GuardUnsafeAccess guard(_thread, _obj);
207
208 T* p = (T*)addr();
209
210 *p = normalize(x);
211 }
212
213
214 template <typename T>
215 T get_volatile() {
216 GuardUnsafeAccess guard(_thread, _obj);
217
218 T* p = (T*)addr();
219
220 if (support_IRIW_for_not_multiple_copy_atomic_cpu) {
221 OrderAccess::fence();
222 }
223
224 T x = OrderAccess::load_acquire((volatile T*)p);
225
226 return x;
227 }
228
229 template <typename T>
230 void put_volatile(T x) {
231 GuardUnsafeAccess guard(_thread, _obj);
232
233 T* p = (T*)addr();
234
235 OrderAccess::release_store_fence((volatile T*)p, normalize(x));
236 }
237
238
239 #ifndef SUPPORTS_NATIVE_CX8
240 jlong get_jlong_locked() {
241 GuardUnsafeAccess guard(_thread, _obj);
242
243 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
244
245 jlong* p = (jlong*)addr();
246
247 jlong x = Atomic::load(p);
248
249 return x;
250 }
251
252 void put_jlong_locked(jlong x) {
253 GuardUnsafeAccess guard(_thread, _obj);
254
255 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
256
257 jlong* p = (jlong*)addr();
258
259 Atomic::store(normalize(x), p);
260 }
261 #endif
262 };
263
264 // Get/PutObject must be special-cased, since it works with handles.
265
266 // These functions allow a null base pointer with an arbitrary address.
267 // But if the base pointer is non-null, the offset should make some sense.
268 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
269 UNSAFE_ENTRY(jobject, Unsafe_GetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
270 oop p = JNIHandles::resolve(obj);
271 oop v;
272
273 if (UseCompressedOops) {
274 narrowOop n = *(narrowOop*)index_oop_from_field_offset_long(p, offset);
275 v = oopDesc::decode_heap_oop(n);
276 } else {
277 v = *(oop*)index_oop_from_field_offset_long(p, offset);
278 }
279
280 jobject ret = JNIHandles::make_local(env, v);
281
282 #if INCLUDE_ALL_GCS
283 // We could be accessing the referent field in a reference
284 // object. If G1 is enabled then we need to register non-null
285 // referent with the SATB barrier.
286 if (UseG1GC) {
287 bool needs_barrier = false;
288
289 if (ret != NULL) {
290 if (offset == java_lang_ref_Reference::referent_offset && obj != NULL) {
291 oop o = JNIHandles::resolve(obj);
292 Klass* k = o->klass();
293 if (InstanceKlass::cast(k)->reference_type() != REF_NONE) {
294 assert(InstanceKlass::cast(k)->is_subclass_of(SystemDictionary::Reference_klass()), "sanity");
295 needs_barrier = true;
296 }
297 }
298 }
299
300 if (needs_barrier) {
301 oop referent = JNIHandles::resolve(ret);
302 G1SATBCardTableModRefBS::enqueue(referent);
303 }
304 }
305 #endif // INCLUDE_ALL_GCS
306
307 return ret;
308 } UNSAFE_END
309
310 UNSAFE_ENTRY(void, Unsafe_PutObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
311 oop x = JNIHandles::resolve(x_h);
312 oop p = JNIHandles::resolve(obj);
313
314 if (UseCompressedOops) {
315 oop_store((narrowOop*)index_oop_from_field_offset_long(p, offset), x);
316 } else {
317 oop_store((oop*)index_oop_from_field_offset_long(p, offset), x);
318 }
319 } UNSAFE_END
320
321 UNSAFE_ENTRY(jobject, Unsafe_GetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
322 oop p = JNIHandles::resolve(obj);
323 void* addr = index_oop_from_field_offset_long(p, offset);
324
325 volatile oop v;
326
327 if (UseCompressedOops) {
328 volatile narrowOop n = *(volatile narrowOop*) addr;
329 (void)const_cast<oop&>(v = oopDesc::decode_heap_oop(n));
330 } else {
331 (void)const_cast<oop&>(v = *(volatile oop*) addr);
332 }
333
334 OrderAccess::acquire();
335 return JNIHandles::make_local(env, v);
336 } UNSAFE_END
337
338 UNSAFE_ENTRY(void, Unsafe_PutObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
339 oop x = JNIHandles::resolve(x_h);
340 oop p = JNIHandles::resolve(obj);
341 void* addr = index_oop_from_field_offset_long(p, offset);
342 OrderAccess::release();
343
344 if (UseCompressedOops) {
345 oop_store((narrowOop*)addr, x);
346 } else {
347 oop_store((oop*)addr, x);
348 }
349
350 OrderAccess::fence();
351 } UNSAFE_END
352
353 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) {
354 oop v = *(oop*) (address) addr;
355
356 return JNIHandles::make_local(env, v);
357 } UNSAFE_END
358
359 UNSAFE_ENTRY(jclass, Unsafe_GetJavaMirror(JNIEnv *env, jobject unsafe, jlong metaspace_klass)) {
360 Klass* klass = (Klass*) (address) metaspace_klass;
361
362 return (jclass) JNIHandles::make_local(klass->java_mirror());
363 } UNSAFE_END
364
365 UNSAFE_ENTRY(jlong, Unsafe_GetKlassPointer(JNIEnv *env, jobject unsafe, jobject obj)) {
366 oop o = JNIHandles::resolve(obj);
367 jlong klass = (jlong) (address) o->klass();
368
369 return klass;
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 // - data: bytes of a class file, a raw memory address (length gives the number of bytes)
796 // - cp_patches: where non-null entries exist, they replace corresponding CP entries in data
797
798 // When you load an anonymous class U, it works as if you changed its name just before loading,
799 // to a name that you will never use again. Since the name is lost, no other class can directly
800 // link to any member of U. Just after U is loaded, the only way to use it is reflectively,
801 // through java.lang.Class methods like Class.newInstance.
802
803 // Access checks for linkage sites within U continue to follow the same rules as for named classes.
804 // The package of an anonymous class is given by the package qualifier on the name under which it was loaded.
805 // An anonymous class also has special privileges to access any member of its host class.
806 // This is the main reason why this loading operation is unsafe. The purpose of this is to
807 // allow language implementations to simulate "open classes"; a host class in effect gets
808 // new code when an anonymous class is loaded alongside it. A less convenient but more
809 // standard way to do this is with reflection, which can also be set to ignore access
810 // restrictions.
811
812 // Access into an anonymous class is possible only through reflection. Therefore, there
813 // are no special access rules for calling into an anonymous class. The relaxed access
814 // rule for the host class is applied in the opposite direction: A host class reflectively
815 // access one of its anonymous classes.
816
817 // If you load the same bytecodes twice, you get two different classes. You can reload
818 // the same bytecodes with or without varying CP patches.
819
820 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
821 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
822 // The CONSTANT_Class entry for that name can be patched to refer directly to U1.
823
824 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as
825 // an outer class (so that U2 is an anonymous inner class of anonymous U1).
826 // It is not possible for a named class, or an older anonymous class, to refer by
827 // name (via its CP) to a newer anonymous class.
828
829 // CP patching may also be used to modify (i.e., hack) the names of methods, classes,
830 // or type descriptors used in the loaded anonymous class.
831
832 // Finally, CP patching may be used to introduce "live" objects into the constant pool,
833 // instead of "dead" strings. A compiled statement like println((Object)"hello") can
834 // be changed to println(greeting), where greeting is an arbitrary object created before
835 // the anonymous class is loaded. This is useful in dynamic languages, in which
836 // various kinds of metaobjects must be introduced as constants into bytecode.
837 // Note the cast (Object), which tells the verifier to expect an arbitrary object,
838 // not just a literal string. For such ldc instructions, the verifier uses the
839 // type Object instead of String, if the loaded constant is not in fact a String.
840
841 static instanceKlassHandle
842 Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
843 jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
844 u1** temp_alloc,
845 TRAPS) {
846 assert(host_class != NULL, "host_class must not be NULL");
847 assert(data != NULL, "data must not be NULL");
848
849 if (UsePerfData) {
850 ClassLoader::unsafe_defineClassCallCounter()->inc();
851 }
852
853 jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
854 assert(length >= 0, "class_bytes_length must not be negative: %d", length);
855
856 int class_bytes_length = (int) length;
857
858 u1* class_bytes = NEW_C_HEAP_ARRAY(u1, length, mtInternal);
859 if (class_bytes == NULL) {
860 THROW_0(vmSymbols::java_lang_OutOfMemoryError());
861 }
862
863 // caller responsible to free it:
864 *temp_alloc = class_bytes;
865
866 jbyte* array_base = typeArrayOop(JNIHandles::resolve_non_null(data))->byte_at_addr(0);
867 Copy::conjoint_jbytes(array_base, class_bytes, length);
868
869 objArrayHandle cp_patches_h;
870 if (cp_patches_jh != NULL) {
871 oop p = JNIHandles::resolve_non_null(cp_patches_jh);
872 assert(p->is_objArray(), "cp_patches must be an object[]");
873 cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
874 }
875
876 const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class));
877 // Primitive types have NULL Klass* fields in their java.lang.Class instances.
878 if (host_klass == NULL) {
879 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
880 }
881
882 const char* host_source = host_klass->external_name();
883 Handle host_loader(THREAD, host_klass->class_loader());
884 Handle host_domain(THREAD, host_klass->protection_domain());
885
886 GrowableArray<Handle>* cp_patches = NULL;
887
888 if (cp_patches_h.not_null()) {
889 int alen = cp_patches_h->length();
890
891 for (int i = alen-1; i >= 0; i--) {
892 oop p = cp_patches_h->obj_at(i);
893 if (p != NULL) {
894 Handle patch(THREAD, p);
895
896 if (cp_patches == NULL) {
897 cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
898 }
899
900 cp_patches->at_put(i, patch);
901 }
902 }
903 }
904
905 ClassFileStream st(class_bytes, class_bytes_length, host_source, ClassFileStream::verify);
906
907 Symbol* no_class_name = NULL;
908 Klass* anonk = SystemDictionary::parse_stream(no_class_name,
909 host_loader,
910 host_domain,
911 &st,
912 host_klass,
913 cp_patches,
914 CHECK_NULL);
915 if (anonk == NULL) {
916 return NULL;
917 }
918
919 return instanceKlassHandle(THREAD, anonk);
920 }
921
922 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) {
923 ResourceMark rm(THREAD);
924
925 instanceKlassHandle anon_klass;
926 jobject res_jh = NULL;
927 u1* temp_alloc = NULL;
928
929 anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data, cp_patches_jh, &temp_alloc, THREAD);
930 if (anon_klass() != NULL) {
931 res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
932 }
933
934 // try/finally clause:
935 if (temp_alloc != NULL) {
936 FREE_C_HEAP_ARRAY(u1, temp_alloc);
937 }
938
939 // The anonymous class loader data has been artificially been kept alive to
940 // this point. The mirror and any instances of this class have to keep
941 // it alive afterwards.
942 if (anon_klass() != NULL) {
943 anon_klass->class_loader_data()->dec_keep_alive();
944 }
945
946 // let caller initialize it as needed...
947
948 return (jclass) res_jh;
949 } UNSAFE_END
950
951
952
953 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
954 ThreadToNativeFromVM ttnfv(thread);
955 env->Throw(thr);
956 } UNSAFE_END
957
958 // JSR166 ------------------------------------------------------------------
959
960 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
961 oop x = JNIHandles::resolve(x_h);
962 oop e = JNIHandles::resolve(e_h);
963 oop p = JNIHandles::resolve(obj);
964 HeapWord* addr = (HeapWord *)index_oop_from_field_offset_long(p, offset);
965 oop res = oopDesc::atomic_compare_exchange_oop(x, addr, e, true);
966 if (res == e) {
967 update_barrier_set((void*)addr, x);
968 }
969 return JNIHandles::make_local(env, res);
970 } UNSAFE_END
971
972 UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
973 oop p = JNIHandles::resolve(obj);
974 jint* addr = (jint *) index_oop_from_field_offset_long(p, offset);
975
976 return (jint)(Atomic::cmpxchg(x, addr, e));
977 } UNSAFE_END
978
979 UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
980 Handle p(THREAD, JNIHandles::resolve(obj));
981 jlong* addr = (jlong*)index_oop_from_field_offset_long(p(), offset);
982
983 #ifdef SUPPORTS_NATIVE_CX8
984 return (jlong)(Atomic::cmpxchg(x, addr, e));
985 #else
986 if (VM_Version::supports_cx8()) {
987 return (jlong)(Atomic::cmpxchg(x, addr, e));
988 } else {
989 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
990
991 jlong val = Atomic::load(addr);
992 if (val == e) {
993 Atomic::store(x, addr);
994 }
995 return val;
996 }
997 #endif
998 } UNSAFE_END
999
1000 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
1001 oop x = JNIHandles::resolve(x_h);
1002 oop e = JNIHandles::resolve(e_h);
1003 oop p = JNIHandles::resolve(obj);
1004 HeapWord* addr = (HeapWord *)index_oop_from_field_offset_long(p, offset);
1005 oop res = oopDesc::atomic_compare_exchange_oop(x, addr, e, true);
1006 if (res != e) {
1007 return false;
1008 }
1009
1010 update_barrier_set((void*)addr, x);
1011
1012 return true;
1013 } UNSAFE_END
1014
1015 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
1016 oop p = JNIHandles::resolve(obj);
1017 jint* addr = (jint *)index_oop_from_field_offset_long(p, offset);
1018
1019 return (jint)(Atomic::cmpxchg(x, addr, e)) == e;
1020 } UNSAFE_END
1021
1022 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
1023 Handle p(THREAD, JNIHandles::resolve(obj));
1024 jlong* addr = (jlong*)index_oop_from_field_offset_long(p(), offset);
1025
1026 #ifdef SUPPORTS_NATIVE_CX8
1027 return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
1028 #else
1029 if (VM_Version::supports_cx8()) {
1030 return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
1031 } else {
1032 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
1033
1034 jlong val = Atomic::load(addr);
1035 if (val != e) {
1036 return false;
1037 }
1038
1039 Atomic::store(x, addr);
1040 return true;
1041 }
1042 #endif
1043 } UNSAFE_END
1044
1045 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
1046 EventThreadPark event;
1047 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
1048
1049 JavaThreadParkedState jtps(thread, time != 0);
1050 thread->parker()->park(isAbsolute != 0, time);
1051
1052 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
1053
1054 if (event.should_commit()) {
1055 oop obj = thread->current_park_blocker();
1056 event.set_klass((obj != NULL) ? obj->klass() : NULL);
1057 event.set_timeout(time);
1058 event.set_address((obj != NULL) ? (TYPE_ADDRESS) cast_from_oop<uintptr_t>(obj) : 0);
1059 event.commit();
1060 }
1061 } UNSAFE_END
1062
1063 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
1064 Parker* p = NULL;
1065
1066 if (jthread != NULL) {
1067 oop java_thread = JNIHandles::resolve_non_null(jthread);
1068 if (java_thread != NULL) {
1069 jlong lp = java_lang_Thread::park_event(java_thread);
1070 if (lp != 0) {
1071 // This cast is OK even though the jlong might have been read
1072 // non-atomically on 32bit systems, since there, one word will
1073 // always be zero anyway and the value set is always the same
1074 p = (Parker*)addr_from_java(lp);
1075 } else {
1076 // Grab lock if apparently null or using older version of library
1077 MutexLocker mu(Threads_lock);
1078 java_thread = JNIHandles::resolve_non_null(jthread);
1079
1080 if (java_thread != NULL) {
1081 JavaThread* thr = java_lang_Thread::thread(java_thread);
1082 if (thr != NULL) {
1083 p = thr->parker();
1084 if (p != NULL) { // Bind to Java thread for next time.
1085 java_lang_Thread::set_park_event(java_thread, addr_to_java(p));
1086 }
1087 }
1088 }
1089 }
1090 }
1091 }
1092
1093 if (p != NULL) {
1094 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
1095 p->unpark();
1096 }
1097 } UNSAFE_END
1098
1099 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
1100 const int max_nelem = 3;
1101 double la[max_nelem];
1102 jint ret;
1103
1104 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
1105 assert(a->is_typeArray(), "must be type array");
1106
1107 ret = os::loadavg(la, nelem);
1108 if (ret == -1) {
1109 return -1;
1110 }
1111
1112 // if successful, ret is the number of samples actually retrieved.
1113 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
1114 switch(ret) {
1115 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
1116 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
1117 case 1: a->double_at_put(0, (jdouble)la[0]); break;
1118 }
1119
1120 return ret;
1121 } UNSAFE_END
1122
1123
1124 /// JVM_RegisterUnsafeMethods
1125
1126 #define ADR "J"
1127
1128 #define LANG "Ljava/lang/"
1129
1130 #define OBJ LANG "Object;"
1131 #define CLS LANG "Class;"
1132 #define FLD LANG "reflect/Field;"
1133 #define THR LANG "Throwable;"
1134
1135 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
1136 #define DAC_Args CLS "[B[" OBJ
1137
1138 #define CC (char*) /*cast a literal from (const char*)*/
1139 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1140
1141 #define DECLARE_GETPUTOOP(Type, Desc) \
1142 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
1143 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \
1144 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
1145 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)}
1146
1147
1148 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1149 {CC "getObject", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObject)},
1150 {CC "putObject", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutObject)},
1151 {CC "getObjectVolatile",CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObjectVolatile)},
1152 {CC "putObjectVolatile",CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutObjectVolatile)},
1153
1154 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1155 {CC "getJavaMirror", CC "(" ADR ")" CLS, FN_PTR(Unsafe_GetJavaMirror)},
1156 {CC "getKlassPointer", CC "(" OBJ ")" ADR, FN_PTR(Unsafe_GetKlassPointer)},
1157
1158 DECLARE_GETPUTOOP(Boolean, Z),
1159 DECLARE_GETPUTOOP(Byte, B),
1160 DECLARE_GETPUTOOP(Short, S),
1161 DECLARE_GETPUTOOP(Char, C),
1162 DECLARE_GETPUTOOP(Int, I),
1163 DECLARE_GETPUTOOP(Long, J),
1164 DECLARE_GETPUTOOP(Float, F),
1165 DECLARE_GETPUTOOP(Double, D),
1166
1167 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1168 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1169 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1170
1171 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1172 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1173 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1174 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1175 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1176 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1177 {CC "addressSize0", CC "()I", FN_PTR(Unsafe_AddressSize0)},
1178 {CC "pageSize", CC "()I", FN_PTR(Unsafe_PageSize)},
1179
1180 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1181 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1182 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1183 {CC "compareAndSwapObject", CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSwapObject)},
1184 {CC "compareAndSwapInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSwapInt)},
1185 {CC "compareAndSwapLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSwapLong)},
1186 {CC "compareAndExchangeObjectVolatile", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeObject)},
1187 {CC "compareAndExchangeIntVolatile", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)},
1188 {CC "compareAndExchangeLongVolatile", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)},
1189
1190 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1191 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1192
1193 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1194
1195 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1196 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1197 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1198
1199 {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)},
1200
1201 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1202
1203 {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)},
1204 {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)},
1205 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1206
1207 {CC "isBigEndian0", CC "()Z", FN_PTR(Unsafe_isBigEndian0)},
1208 {CC "unalignedAccess0", CC "()Z", FN_PTR(Unsafe_unalignedAccess0)}
1209 };
1210
1211 #undef CC
1212 #undef FN_PTR
1213
1214 #undef ADR
1215 #undef LANG
1216 #undef OBJ
1217 #undef CLS
1218 #undef FLD
1219 #undef THR
1220 #undef DC_Args
1221 #undef DAC_Args
1222
1223 #undef DECLARE_GETPUTOOP
1224
1225
1226 // This function is exported, used by NativeLookup.
1227 // The Unsafe_xxx functions above are called only from the interpreter.
1228 // The optimizer looks at names and signatures to recognize
1229 // individual functions.
1230
1231 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1232 ThreadToNativeFromVM ttnfv(thread);
1233
1234 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1235 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1236 } JVM_END