1 /*
2 * Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "jni.h"
27 #include "jvm.h"
28 #include "classfile/classFileStream.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "jfr/jfrEvents.hpp"
31 #include "memory/allocation.inline.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "logging/log.hpp"
34 #include "oops/access.inline.hpp"
35 #include "oops/fieldStreams.hpp"
36 #include "oops/objArrayOop.inline.hpp"
37 #include "oops/oop.inline.hpp"
38 #include "oops/typeArrayOop.inline.hpp"
39 #include "oops/valueArrayKlass.hpp"
40 #include "oops/valueArrayOop.hpp"
41 #include "oops/valueArrayOop.inline.hpp"
42 #include "prims/unsafe.hpp"
43 #include "runtime/atomic.hpp"
44 #include "runtime/fieldDescriptor.inline.hpp"
45 #include "runtime/globals.hpp"
46 #include "runtime/interfaceSupport.inline.hpp"
47 #include "runtime/jniHandles.inline.hpp"
48 #include "runtime/orderAccess.hpp"
49 #include "runtime/reflection.hpp"
50 #include "runtime/thread.hpp"
51 #include "runtime/threadSMR.hpp"
52 #include "runtime/vm_version.hpp"
53 #include "services/threadService.hpp"
54 #include "utilities/align.hpp"
55 #include "utilities/copy.hpp"
56 #include "utilities/dtrace.hpp"
57 #include "utilities/macros.hpp"
58
59 /**
60 * Implementation of the jdk.internal.misc.Unsafe class
61 */
62
63
64 #define MAX_OBJECT_SIZE \
65 ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
66 + ((julong)max_jint * sizeof(double)) )
67
68
69 #define UNSAFE_ENTRY(result_type, header) \
70 JVM_ENTRY(static result_type, header)
71
72 #define UNSAFE_LEAF(result_type, header) \
73 JVM_LEAF(static result_type, header)
74
75 #define UNSAFE_END JVM_END
76
77
78 static inline void* addr_from_java(jlong addr) {
79 // This assert fails in a variety of ways on 32-bit systems.
80 // It is impossible to predict whether native code that converts
81 // pointers to longs will sign-extend or zero-extend the addresses.
82 //assert(addr == (uintptr_t)addr, "must not be odd high bits");
83 return (void*)(uintptr_t)addr;
84 }
85
86 static inline jlong addr_to_java(void* p) {
87 assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
88 return (uintptr_t)p;
89 }
90
91
92 // Note: The VM's obj_field and related accessors use byte-scaled
93 // ("unscaled") offsets, just as the unsafe methods do.
94
95 // However, the method Unsafe.fieldOffset explicitly declines to
96 // guarantee this. The field offset values manipulated by the Java user
97 // through the Unsafe API are opaque cookies that just happen to be byte
98 // offsets. We represent this state of affairs by passing the cookies
99 // through conversion functions when going between the VM and the Unsafe API.
100 // The conversion functions just happen to be no-ops at present.
101
102 static inline jlong field_offset_to_byte_offset(jlong field_offset) {
103 return field_offset;
104 }
105
106 static inline jlong field_offset_from_byte_offset(jlong byte_offset) {
107 return byte_offset;
108 }
109
110 static inline void assert_field_offset_sane(oop p, jlong field_offset) {
111 #ifdef ASSERT
112 jlong byte_offset = field_offset_to_byte_offset(field_offset);
113
114 if (p != NULL) {
115 assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
116 if (byte_offset == (jint)byte_offset) {
117 void* ptr_plus_disp = (address)p + byte_offset;
118 assert(p->field_addr_raw((jint)byte_offset) == ptr_plus_disp,
119 "raw [ptr+disp] must be consistent with oop::field_addr_raw");
120 }
121 jlong p_size = HeapWordSize * (jlong)(p->size());
122 assert(byte_offset < p_size, "Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, (int64_t)byte_offset, (int64_t)p_size);
123 }
124 #endif
125 }
126
127 static inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
128 assert_field_offset_sane(p, field_offset);
129 jlong byte_offset = field_offset_to_byte_offset(field_offset);
130
131 if (p != NULL) {
132 p = Access<>::resolve(p);
133 }
134
135 if (sizeof(char*) == sizeof(jint)) { // (this constant folds!)
136 return (address)p + (jint) byte_offset;
137 } else {
138 return (address)p + byte_offset;
139 }
140 }
141
142 // Externally callable versions:
143 // (Use these in compiler intrinsics which emulate unsafe primitives.)
144 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
145 return field_offset;
146 }
147 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
148 return byte_offset;
149 }
150
151
152 ///// Data read/writes on the Java heap and in native (off-heap) memory
153
154 /**
155 * Helper class for accessing memory.
156 *
157 * Normalizes values and wraps accesses in
158 * JavaThread::doing_unsafe_access() if needed.
159 */
160 template <typename T>
161 class MemoryAccess : StackObj {
162 JavaThread* _thread;
163 oop _obj;
164 ptrdiff_t _offset;
165
166 // Resolves and returns the address of the memory access.
167 // This raw memory access may fault, so we make sure it happens within the
168 // guarded scope by making the access volatile at least. Since the store
169 // of Thread::set_doing_unsafe_access() is also volatile, these accesses
170 // can not be reordered by the compiler. Therefore, if the access triggers
171 // a fault, we will know that Thread::doing_unsafe_access() returns true.
172 volatile T* addr() {
173 void* addr = index_oop_from_field_offset_long(_obj, _offset);
174 return static_cast<volatile T*>(addr);
175 }
176
177 template <typename U>
178 U normalize_for_write(U x) {
179 return x;
180 }
181
182 jboolean normalize_for_write(jboolean x) {
183 return x & 1;
184 }
185
186 template <typename U>
187 U normalize_for_read(U x) {
188 return x;
189 }
190
191 jboolean normalize_for_read(jboolean x) {
192 return x != 0;
193 }
194
195 /**
196 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access()
197 */
198 class GuardUnsafeAccess {
199 JavaThread* _thread;
200
201 public:
202 GuardUnsafeAccess(JavaThread* thread) : _thread(thread) {
203 // native/off-heap access which may raise SIGBUS if accessing
204 // memory mapped file data in a region of the file which has
205 // been truncated and is now invalid
206 _thread->set_doing_unsafe_access(true);
207 }
208
209 ~GuardUnsafeAccess() {
210 _thread->set_doing_unsafe_access(false);
211 }
212 };
213
214 public:
215 MemoryAccess(JavaThread* thread, jobject obj, jlong offset)
216 : _thread(thread), _obj(JNIHandles::resolve(obj)), _offset((ptrdiff_t)offset) {
217 assert_field_offset_sane(_obj, offset);
218 }
219
220 T get() {
221 if (_obj == NULL) {
222 GuardUnsafeAccess guard(_thread);
223 T ret = RawAccess<>::load(addr());
224 return normalize_for_read(ret);
225 } else {
226 T ret = HeapAccess<>::load_at(_obj, _offset);
227 return normalize_for_read(ret);
228 }
229 }
230
231 void put(T x) {
232 if (_obj == NULL) {
233 GuardUnsafeAccess guard(_thread);
234 RawAccess<>::store(addr(), normalize_for_write(x));
235 } else {
236 HeapAccess<>::store_at(_obj, _offset, normalize_for_write(x));
237 }
238 }
239
240
241 T get_volatile() {
242 if (_obj == NULL) {
243 GuardUnsafeAccess guard(_thread);
244 volatile T ret = RawAccess<MO_SEQ_CST>::load(addr());
245 return normalize_for_read(ret);
246 } else {
247 T ret = HeapAccess<MO_SEQ_CST>::load_at(_obj, _offset);
248 return normalize_for_read(ret);
249 }
250 }
251
252 void put_volatile(T x) {
253 if (_obj == NULL) {
254 GuardUnsafeAccess guard(_thread);
255 RawAccess<MO_SEQ_CST>::store(addr(), normalize_for_write(x));
256 } else {
257 HeapAccess<MO_SEQ_CST>::store_at(_obj, _offset, normalize_for_write(x));
258 }
259 }
260 };
261
262 #ifdef ASSERT
263 /*
264 * Get the field descriptor of the field of the given object at the given offset.
265 */
266 static bool get_field_descriptor(oop p, jlong offset, fieldDescriptor* fd) {
267 bool found = false;
268 Klass* k = p->klass();
269 if (k->is_instance_klass()) {
270 InstanceKlass* ik = InstanceKlass::cast(k);
271 found = ik->find_field_from_offset((int)offset, false, fd);
272 if (!found && ik->is_mirror_instance_klass()) {
273 Klass* k2 = java_lang_Class::as_Klass(p);
274 if (k2->is_instance_klass()) {
275 ik = InstanceKlass::cast(k2);
276 found = ik->find_field_from_offset((int)offset, true, fd);
277 }
278 }
279 }
280 return found;
281 }
282 #endif // ASSERT
283
284 static void assert_and_log_unsafe_value_type_access(oop p, jlong offset, ValueKlass* vk) {
285 Klass* k = p->klass();
286
287 #ifdef ASSERT
288 if (k->is_instance_klass()) {
289 assert_field_offset_sane(p, offset);
290 fieldDescriptor fd;
291 bool found = get_field_descriptor(p, offset, &fd);
292 assert(found, "value field not found");
293 assert(fd.is_flattened(), "field not flat");
294 } else if (k->is_valueArray_klass()) {
295 ValueArrayKlass* vak = ValueArrayKlass::cast(k);
296 int index = (offset - vak->array_header_in_bytes()) / vak->element_byte_size();
297 address dest = (address)((valueArrayOop)p)->value_at_addr(index, vak->layout_helper());
298 assert(dest == ((address)p) + offset, "invalid offset");
299 } else {
300 ShouldNotReachHere();
301 }
302 #endif // ASSERT
303
304 if (log_is_enabled(Trace, valuetypes)) {
305 if (k->is_valueArray_klass()) {
306 ValueArrayKlass* vak = ValueArrayKlass::cast(k);
307 int index = (offset - vak->array_header_in_bytes()) / vak->element_byte_size();
308 address dest = (address)((valueArrayOop)p)->value_at_addr(index, vak->layout_helper());
309 log_trace(valuetypes)("array type %s index %d element size %d offset " SIZE_FORMAT_HEX " at " INTPTR_FORMAT,
310 vak->external_name(), index, vak->element_byte_size(), offset, p2i(dest));
311 } else {
312 log_trace(valuetypes)("field type %s at offset " SIZE_FORMAT_HEX,
313 vk->external_name(), offset);
314 }
315 }
316 }
317
318 // These functions allow a null base pointer with an arbitrary address.
319 // But if the base pointer is non-null, the offset should make some sense.
320 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
321 UNSAFE_ENTRY(jobject, Unsafe_GetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
322 oop p = JNIHandles::resolve(obj);
323 assert_field_offset_sane(p, offset);
324 oop v = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
325 return JNIHandles::make_local(env, v);
326 } UNSAFE_END
327
328 UNSAFE_ENTRY(void, Unsafe_PutObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
329 oop x = JNIHandles::resolve(x_h);
330 oop p = JNIHandles::resolve(obj);
331 assert_field_offset_sane(p, offset);
332 HeapAccess<ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
333 } UNSAFE_END
334
335 UNSAFE_ENTRY(jboolean, Unsafe_IsFlattenedArray(JNIEnv *env, jobject unsafe, jclass c)) {
336 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(c));
337 return k->is_valueArray_klass();
338 } UNSAFE_END
339
340 UNSAFE_ENTRY(jobject, Unsafe_GetValue(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jclass c)) {
341 oop p = JNIHandles::resolve(obj);
342 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(c));
343 ValueKlass* vk = ValueKlass::cast(k);
344 assert_and_log_unsafe_value_type_access(p, offset, vk);
345 Handle p_h(THREAD, p);
346 oop v = vk->allocate_instance(CHECK_NULL); // allocate instance
347 vk->initialize(CHECK_NULL); // If field is a default value, value class might not be initialized yet
348 vk->value_store(((char*)(oopDesc*)p_h()) + offset,
349 vk->data_for_oop(v),
350 true, true);
351 return JNIHandles::make_local(env, v);
352 } UNSAFE_END
353
354 UNSAFE_ENTRY(void, Unsafe_PutValue(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jclass c, jobject value)) {
355 oop v = JNIHandles::resolve(value);
356 oop p = JNIHandles::resolve(obj);
357 Klass* k = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(c));
358 ValueKlass* vk = ValueKlass::cast(k);
359 assert_and_log_unsafe_value_type_access(p, offset, vk);
360 vk->value_store(vk->data_for_oop(v),
361 ((char*)(oopDesc*)p) + offset, true, true);
362 } UNSAFE_END
363
364 UNSAFE_ENTRY(jobject, Unsafe_GetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
365 oop p = JNIHandles::resolve(obj);
366 assert_field_offset_sane(p, offset);
367 oop v = HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset);
368 return JNIHandles::make_local(env, v);
369 } UNSAFE_END
370
371 UNSAFE_ENTRY(void, Unsafe_PutObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
372 oop x = JNIHandles::resolve(x_h);
373 oop p = JNIHandles::resolve(obj);
374 assert_field_offset_sane(p, offset);
375 HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x);
376 } UNSAFE_END
377
378 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) {
379 oop v = *(oop*) (address) addr;
380 return JNIHandles::make_local(env, v);
381 } UNSAFE_END
382
383 UNSAFE_LEAF(jboolean, Unsafe_isBigEndian0(JNIEnv *env, jobject unsafe)) {
384 #ifdef VM_LITTLE_ENDIAN
385 return false;
386 #else
387 return true;
388 #endif
389 } UNSAFE_END
390
391 UNSAFE_LEAF(jint, Unsafe_unalignedAccess0(JNIEnv *env, jobject unsafe)) {
392 return UseUnalignedAccesses;
393 } UNSAFE_END
394
395 #define DEFINE_GETSETOOP(java_type, Type) \
396 \
397 UNSAFE_ENTRY(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
398 return MemoryAccess<java_type>(thread, obj, offset).get(); \
399 } UNSAFE_END \
400 \
401 UNSAFE_ENTRY(void, Unsafe_Put##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
402 MemoryAccess<java_type>(thread, obj, offset).put(x); \
403 } UNSAFE_END \
404 \
405 // END DEFINE_GETSETOOP.
406
407 DEFINE_GETSETOOP(jboolean, Boolean)
408 DEFINE_GETSETOOP(jbyte, Byte)
409 DEFINE_GETSETOOP(jshort, Short);
410 DEFINE_GETSETOOP(jchar, Char);
411 DEFINE_GETSETOOP(jint, Int);
412 DEFINE_GETSETOOP(jlong, Long);
413 DEFINE_GETSETOOP(jfloat, Float);
414 DEFINE_GETSETOOP(jdouble, Double);
415
416 #undef DEFINE_GETSETOOP
417
418 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \
419 \
420 UNSAFE_ENTRY(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
421 return MemoryAccess<java_type>(thread, obj, offset).get_volatile(); \
422 } UNSAFE_END \
423 \
424 UNSAFE_ENTRY(void, Unsafe_Put##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
425 MemoryAccess<java_type>(thread, obj, offset).put_volatile(x); \
426 } UNSAFE_END \
427 \
428 // END DEFINE_GETSETOOP_VOLATILE.
429
430 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
431 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
432 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
433 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
434 DEFINE_GETSETOOP_VOLATILE(jint, Int);
435 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
436 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
437 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
438
439 #undef DEFINE_GETSETOOP_VOLATILE
440
441 UNSAFE_LEAF(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe)) {
442 OrderAccess::acquire();
443 } UNSAFE_END
444
445 UNSAFE_LEAF(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe)) {
446 OrderAccess::release();
447 } UNSAFE_END
448
449 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
450 OrderAccess::fence();
451 } UNSAFE_END
452
453 ////// Allocation requests
454
455 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
456 ThreadToNativeFromVM ttnfv(thread);
457 return env->AllocObject(cls);
458 } UNSAFE_END
459
460 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) {
461 size_t sz = (size_t)size;
462
463 sz = align_up(sz, HeapWordSize);
464 void* x = os::malloc(sz, mtOther);
465
466 return addr_to_java(x);
467 } UNSAFE_END
468
469 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) {
470 void* p = addr_from_java(addr);
471 size_t sz = (size_t)size;
472 sz = align_up(sz, HeapWordSize);
473
474 void* x = os::realloc(p, sz, mtOther);
475
476 return addr_to_java(x);
477 } UNSAFE_END
478
479 UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) {
480 void* p = addr_from_java(addr);
481
482 os::free(p);
483 } UNSAFE_END
484
485 UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) {
486 size_t sz = (size_t)size;
487
488 oop base = JNIHandles::resolve(obj);
489 void* p = index_oop_from_field_offset_long(base, offset);
490
491 Copy::fill_to_memory_atomic(p, sz, value);
492 } UNSAFE_END
493
494 UNSAFE_ENTRY(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) {
495 size_t sz = (size_t)size;
496
497 oop srcp = JNIHandles::resolve(srcObj);
498 oop dstp = JNIHandles::resolve(dstObj);
499
500 void* src = index_oop_from_field_offset_long(srcp, srcOffset);
501 void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
502
503 Copy::conjoint_memory_atomic(src, dst, sz);
504 } UNSAFE_END
505
506 // This function is a leaf since if the source and destination are both in native memory
507 // the copy may potentially be very large, and we don't want to disable GC if we can avoid it.
508 // If either source or destination (or both) are on the heap, the function will enter VM using
509 // JVM_ENTRY_FROM_LEAF
510 UNSAFE_LEAF(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) {
511 size_t sz = (size_t)size;
512 size_t esz = (size_t)elemSize;
513
514 if (srcObj == NULL && dstObj == NULL) {
515 // Both src & dst are in native memory
516 address src = (address)srcOffset;
517 address dst = (address)dstOffset;
518
519 Copy::conjoint_swap(src, dst, sz, esz);
520 } else {
521 // At least one of src/dst are on heap, transition to VM to access raw pointers
522
523 JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) {
524 oop srcp = JNIHandles::resolve(srcObj);
525 oop dstp = JNIHandles::resolve(dstObj);
526
527 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset);
528 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset);
529
530 Copy::conjoint_swap(src, dst, sz, esz);
531 } JVM_END
532 }
533 } UNSAFE_END
534
535 ////// Random queries
536
537 UNSAFE_LEAF(jint, Unsafe_AddressSize0(JNIEnv *env, jobject unsafe)) {
538 return sizeof(void*);
539 } UNSAFE_END
540
541 UNSAFE_LEAF(jint, Unsafe_PageSize()) {
542 return os::vm_page_size();
543 } UNSAFE_END
544
545 static jlong find_field_offset(jclass clazz, jstring name, TRAPS) {
546 assert(clazz != NULL, "clazz must not be NULL");
547 assert(name != NULL, "name must not be NULL");
548
549 ResourceMark rm(THREAD);
550 char *utf_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name));
551
552 InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz)));
553
554 jint offset = -1;
555 for (JavaFieldStream fs(k); !fs.done(); fs.next()) {
556 Symbol *name = fs.name();
557 if (name->equals(utf_name)) {
558 offset = fs.offset();
559 break;
560 }
561 }
562 if (offset < 0) {
563 THROW_0(vmSymbols::java_lang_InternalError());
564 }
565 return field_offset_from_byte_offset(offset);
566 }
567
568 static jlong find_field_offset(jobject field, int must_be_static, TRAPS) {
569 assert(field != NULL, "field must not be NULL");
570
571 oop reflected = JNIHandles::resolve_non_null(field);
572 oop mirror = java_lang_reflect_Field::clazz(reflected);
573 Klass* k = java_lang_Class::as_Klass(mirror);
574 int slot = java_lang_reflect_Field::slot(reflected);
575 int modifiers = java_lang_reflect_Field::modifiers(reflected);
576
577 if (must_be_static >= 0) {
578 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
579 if (must_be_static != really_is_static) {
580 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
581 }
582 }
583
584 int offset = InstanceKlass::cast(k)->field_offset(slot);
585 return field_offset_from_byte_offset(offset);
586 }
587
588 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
589 return find_field_offset(field, 0, THREAD);
590 } UNSAFE_END
591
592 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset1(JNIEnv *env, jobject unsafe, jclass c, jstring name)) {
593 return find_field_offset(c, name, THREAD);
594 } UNSAFE_END
595
596 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
597 return find_field_offset(field, 1, THREAD);
598 } UNSAFE_END
599
600 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) {
601 assert(field != NULL, "field must not be NULL");
602
603 // Note: In this VM implementation, a field address is always a short
604 // offset from the base of a a klass metaobject. Thus, the full dynamic
605 // range of the return type is never used. However, some implementations
606 // might put the static field inside an array shared by many classes,
607 // or even at a fixed address, in which case the address could be quite
608 // large. In that last case, this function would return NULL, since
609 // the address would operate alone, without any base pointer.
610
611 oop reflected = JNIHandles::resolve_non_null(field);
612 oop mirror = java_lang_reflect_Field::clazz(reflected);
613 int modifiers = java_lang_reflect_Field::modifiers(reflected);
614
615 if ((modifiers & JVM_ACC_STATIC) == 0) {
616 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
617 }
618
619 return JNIHandles::make_local(env, mirror);
620 } UNSAFE_END
621
622 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
623 assert(clazz != NULL, "clazz must not be NULL");
624
625 oop mirror = JNIHandles::resolve_non_null(clazz);
626
627 Klass* klass = java_lang_Class::as_Klass(mirror);
628 if (klass != NULL && klass->should_be_initialized()) {
629 InstanceKlass* k = InstanceKlass::cast(klass);
630 k->initialize(CHECK);
631 }
632 }
633 UNSAFE_END
634
635 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
636 assert(clazz != NULL, "clazz must not be NULL");
637
638 oop mirror = JNIHandles::resolve_non_null(clazz);
639 Klass* klass = java_lang_Class::as_Klass(mirror);
640
641 if (klass != NULL && klass->should_be_initialized()) {
642 return true;
643 }
644
645 return false;
646 }
647 UNSAFE_END
648
649 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) {
650 assert(clazz != NULL, "clazz must not be NULL");
651
652 oop mirror = JNIHandles::resolve_non_null(clazz);
653 Klass* k = java_lang_Class::as_Klass(mirror);
654
655 if (k == NULL || !k->is_array_klass()) {
656 THROW(vmSymbols::java_lang_InvalidClassException());
657 } else if (k->is_objArray_klass()) {
658 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
659 scale = heapOopSize;
660 } else if (k->is_typeArray_klass()) {
661 TypeArrayKlass* tak = TypeArrayKlass::cast(k);
662 base = tak->array_header_in_bytes();
663 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
664 scale = (1 << tak->log2_element_size());
665 } else if (k->is_valueArray_klass()) {
666 ValueArrayKlass* vak = ValueArrayKlass::cast(k);
667 ValueKlass* vklass = vak->element_klass();
668 base = vak->array_header_in_bytes();
669 scale = vak->element_byte_size();
670 } else {
671 ShouldNotReachHere();
672 }
673 }
674
675 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) {
676 int base = 0, scale = 0;
677 getBaseAndScale(base, scale, clazz, CHECK_0);
678
679 return field_offset_from_byte_offset(base);
680 } UNSAFE_END
681
682
683 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) {
684 int base = 0, scale = 0;
685 getBaseAndScale(base, scale, clazz, CHECK_0);
686
687 // This VM packs both fields and array elements down to the byte.
688 // But watch out: If this changes, so that array references for
689 // a given primitive type (say, T_BOOLEAN) use different memory units
690 // than fields, this method MUST return zero for such arrays.
691 // For example, the VM used to store sub-word sized fields in full
692 // words in the object layout, so that accessors like getByte(Object,int)
693 // did not really do what one might expect for arrays. Therefore,
694 // this function used to report a zero scale factor, so that the user
695 // would know not to attempt to access sub-word array elements.
696 // // Code for unpacked fields:
697 // if (scale < wordSize) return 0;
698
699 // The following allows for a pretty general fieldOffset cookie scheme,
700 // but requires it to be linear in byte offset.
701 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
702 } UNSAFE_END
703
704
705 static inline void throw_new(JNIEnv *env, const char *ename) {
706 jclass cls = env->FindClass(ename);
707 if (env->ExceptionCheck()) {
708 env->ExceptionClear();
709 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", ename);
710 return;
711 }
712
713 env->ThrowNew(cls, NULL);
714 }
715
716 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
717 // Code lifted from JDK 1.3 ClassLoader.c
718
719 jbyte *body;
720 char *utfName = NULL;
721 jclass result = 0;
722 char buf[128];
723
724 assert(data != NULL, "Class bytes must not be NULL");
725 assert(length >= 0, "length must not be negative: %d", length);
726
727 if (UsePerfData) {
728 ClassLoader::unsafe_defineClassCallCounter()->inc();
729 }
730
731 body = NEW_C_HEAP_ARRAY(jbyte, length, mtInternal);
732 if (body == NULL) {
733 throw_new(env, "java/lang/OutOfMemoryError");
734 return 0;
735 }
736
737 env->GetByteArrayRegion(data, offset, length, body);
738 if (env->ExceptionOccurred()) {
739 goto free_body;
740 }
741
742 if (name != NULL) {
743 uint len = env->GetStringUTFLength(name);
744 int unicode_len = env->GetStringLength(name);
745
746 if (len >= sizeof(buf)) {
747 utfName = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
748 if (utfName == NULL) {
749 throw_new(env, "java/lang/OutOfMemoryError");
750 goto free_body;
751 }
752 } else {
753 utfName = buf;
754 }
755
756 env->GetStringUTFRegion(name, 0, unicode_len, utfName);
757
758 for (uint i = 0; i < len; i++) {
759 if (utfName[i] == '.') utfName[i] = '/';
760 }
761 }
762
763 result = JVM_DefineClass(env, utfName, loader, body, length, pd);
764
765 if (utfName && utfName != buf) {
766 FREE_C_HEAP_ARRAY(char, utfName);
767 }
768
769 free_body:
770 FREE_C_HEAP_ARRAY(jbyte, body);
771 return result;
772 }
773
774
775 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) {
776 ThreadToNativeFromVM ttnfv(thread);
777
778 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
779 } UNSAFE_END
780
781
782 // define a class but do not make it known to the class loader or system dictionary
783 // - host_class: supplies context for linkage, access control, protection domain, and class loader
784 // if host_class is itself anonymous then it is replaced with its host class.
785 // - data: bytes of a class file, a raw memory address (length gives the number of bytes)
786 // - cp_patches: where non-null entries exist, they replace corresponding CP entries in data
787
788 // When you load an anonymous class U, it works as if you changed its name just before loading,
789 // to a name that you will never use again. Since the name is lost, no other class can directly
790 // link to any member of U. Just after U is loaded, the only way to use it is reflectively,
791 // through java.lang.Class methods like Class.newInstance.
792
793 // The package of an anonymous class must either match its host's class's package or be in the
794 // unnamed package. If it is in the unnamed package then it will be put in its host class's
795 // package.
796 //
797
798 // Access checks for linkage sites within U continue to follow the same rules as for named classes.
799 // An anonymous class also has special privileges to access any member of its host class.
800 // This is the main reason why this loading operation is unsafe. The purpose of this is to
801 // allow language implementations to simulate "open classes"; a host class in effect gets
802 // new code when an anonymous class is loaded alongside it. A less convenient but more
803 // standard way to do this is with reflection, which can also be set to ignore access
804 // restrictions.
805
806 // Access into an anonymous class is possible only through reflection. Therefore, there
807 // are no special access rules for calling into an anonymous class. The relaxed access
808 // rule for the host class is applied in the opposite direction: A host class reflectively
809 // access one of its anonymous classes.
810
811 // If you load the same bytecodes twice, you get two different classes. You can reload
812 // the same bytecodes with or without varying CP patches.
813
814 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
815 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
816 // The CONSTANT_Class entry for that name can be patched to refer directly to U1.
817
818 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as
819 // an outer class (so that U2 is an anonymous inner class of anonymous U1).
820 // It is not possible for a named class, or an older anonymous class, to refer by
821 // name (via its CP) to a newer anonymous class.
822
823 // CP patching may also be used to modify (i.e., hack) the names of methods, classes,
824 // or type descriptors used in the loaded anonymous class.
825
826 // Finally, CP patching may be used to introduce "live" objects into the constant pool,
827 // instead of "dead" strings. A compiled statement like println((Object)"hello") can
828 // be changed to println(greeting), where greeting is an arbitrary object created before
829 // the anonymous class is loaded. This is useful in dynamic languages, in which
830 // various kinds of metaobjects must be introduced as constants into bytecode.
831 // Note the cast (Object), which tells the verifier to expect an arbitrary object,
832 // not just a literal string. For such ldc instructions, the verifier uses the
833 // type Object instead of String, if the loaded constant is not in fact a String.
834
835 static InstanceKlass*
836 Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
837 jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
838 u1** temp_alloc,
839 TRAPS) {
840 assert(host_class != NULL, "host_class must not be NULL");
841 assert(data != NULL, "data must not be NULL");
842
843 if (UsePerfData) {
844 ClassLoader::unsafe_defineClassCallCounter()->inc();
845 }
846
847 jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
848 assert(length >= 0, "class_bytes_length must not be negative: %d", length);
849
850 int class_bytes_length = (int) length;
851
852 u1* class_bytes = NEW_C_HEAP_ARRAY(u1, length, mtInternal);
853 if (class_bytes == NULL) {
854 THROW_0(vmSymbols::java_lang_OutOfMemoryError());
855 }
856
857 // caller responsible to free it:
858 *temp_alloc = class_bytes;
859
860 ArrayAccess<>::arraycopy_to_native(arrayOop(JNIHandles::resolve_non_null(data)), typeArrayOopDesc::element_offset<jbyte>(0),
861 reinterpret_cast<jbyte*>(class_bytes), length);
862
863 objArrayHandle cp_patches_h;
864 if (cp_patches_jh != NULL) {
865 oop p = JNIHandles::resolve_non_null(cp_patches_jh);
866 assert(p->is_objArray(), "cp_patches must be an object[]");
867 cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
868 }
869
870 const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class));
871
872 // Make sure it's the real host class, not another anonymous class.
873 while (host_klass != NULL && host_klass->is_instance_klass() &&
874 InstanceKlass::cast(host_klass)->is_unsafe_anonymous()) {
875 host_klass = InstanceKlass::cast(host_klass)->unsafe_anonymous_host();
876 }
877
878 // Primitive types have NULL Klass* fields in their java.lang.Class instances.
879 if (host_klass == NULL) {
880 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Host class is null");
881 }
882
883 assert(host_klass->is_instance_klass(), "Host class must be an instance class");
884
885 const char* host_source = host_klass->external_name();
886 Handle host_loader(THREAD, host_klass->class_loader());
887 Handle host_domain(THREAD, host_klass->protection_domain());
888
889 GrowableArray<Handle>* cp_patches = NULL;
890
891 if (cp_patches_h.not_null()) {
892 int alen = cp_patches_h->length();
893
894 for (int i = alen-1; i >= 0; i--) {
895 oop p = cp_patches_h->obj_at(i);
896 if (p != NULL) {
897 Handle patch(THREAD, p);
898
899 if (cp_patches == NULL) {
900 cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
901 }
902
903 cp_patches->at_put(i, patch);
904 }
905 }
906 }
907
908 ClassFileStream st(class_bytes, class_bytes_length, host_source, ClassFileStream::verify);
909
910 Symbol* no_class_name = NULL;
911 Klass* anonk = SystemDictionary::parse_stream(no_class_name,
912 host_loader,
913 host_domain,
914 &st,
915 InstanceKlass::cast(host_klass),
916 cp_patches,
917 CHECK_NULL);
918 if (anonk == NULL) {
919 return NULL;
920 }
921
922 return InstanceKlass::cast(anonk);
923 }
924
925 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) {
926 ResourceMark rm(THREAD);
927
928 jobject res_jh = NULL;
929 u1* temp_alloc = NULL;
930
931 InstanceKlass* anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data, cp_patches_jh, &temp_alloc, THREAD);
932 if (anon_klass != NULL) {
933 res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
934 }
935
936 // try/finally clause:
937 if (temp_alloc != NULL) {
938 FREE_C_HEAP_ARRAY(u1, temp_alloc);
939 }
940
941 // The anonymous class loader data has been artificially been kept alive to
942 // this point. The mirror and any instances of this class have to keep
943 // it alive afterwards.
944 if (anon_klass != NULL) {
945 anon_klass->class_loader_data()->dec_keep_alive();
946 }
947
948 // let caller initialize it as needed...
949
950 return (jclass) res_jh;
951 } UNSAFE_END
952
953
954
955 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
956 ThreadToNativeFromVM ttnfv(thread);
957 env->Throw(thr);
958 } UNSAFE_END
959
960 // JSR166 ------------------------------------------------------------------
961
962 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
963 oop x = JNIHandles::resolve(x_h);
964 oop e = JNIHandles::resolve(e_h);
965 oop p = JNIHandles::resolve(obj);
966 assert_field_offset_sane(p, offset);
967 oop res = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
968 return JNIHandles::make_local(env, res);
969 } UNSAFE_END
970
971 UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
972 oop p = JNIHandles::resolve(obj);
973 if (p == NULL) {
974 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
975 return RawAccess<>::atomic_cmpxchg(x, addr, e);
976 } else {
977 assert_field_offset_sane(p, offset);
978 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
979 }
980 } UNSAFE_END
981
982 UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
983 oop p = JNIHandles::resolve(obj);
984 if (p == NULL) {
985 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
986 return RawAccess<>::atomic_cmpxchg(x, addr, e);
987 } else {
988 assert_field_offset_sane(p, offset);
989 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
990 }
991 } UNSAFE_END
992
993 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
994 oop x = JNIHandles::resolve(x_h);
995 oop e = JNIHandles::resolve(e_h);
996 oop p = JNIHandles::resolve(obj);
997 assert_field_offset_sane(p, offset);
998 oop ret = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e);
999 return oopDesc::equals(ret, e);
1000 } UNSAFE_END
1001
1002 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
1003 oop p = JNIHandles::resolve(obj);
1004 if (p == NULL) {
1005 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset);
1006 return RawAccess<>::atomic_cmpxchg(x, addr, e) == e;
1007 } else {
1008 assert_field_offset_sane(p, offset);
1009 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e) == e;
1010 }
1011 } UNSAFE_END
1012
1013 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
1014 oop p = JNIHandles::resolve(obj);
1015 if (p == NULL) {
1016 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset);
1017 return RawAccess<>::atomic_cmpxchg(x, addr, e) == e;
1018 } else {
1019 assert_field_offset_sane(p, offset);
1020 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e) == e;
1021 }
1022 } UNSAFE_END
1023
1024 static void post_thread_park_event(EventThreadPark* event, const oop obj, jlong timeout) {
1025 assert(event != NULL, "invariant");
1026 assert(event->should_commit(), "invariant");
1027 event->set_parkedClass((obj != NULL) ? obj->klass() : NULL);
1028 event->set_timeout(timeout);
1029 event->set_address((obj != NULL) ? (u8)cast_from_oop<uintptr_t>(obj) : 0);
1030 event->commit();
1031 }
1032
1033 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
1034 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
1035 EventThreadPark event;
1036
1037 JavaThreadParkedState jtps(thread, time != 0);
1038 thread->parker()->park(isAbsolute != 0, time);
1039 if (event.should_commit()) {
1040 post_thread_park_event(&event, thread->current_park_blocker(), time);
1041 }
1042 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
1043 } UNSAFE_END
1044
1045 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
1046 Parker* p = NULL;
1047
1048 if (jthread != NULL) {
1049 ThreadsListHandle tlh;
1050 JavaThread* thr = NULL;
1051 oop java_thread = NULL;
1052 (void) tlh.cv_internal_thread_to_JavaThread(jthread, &thr, &java_thread);
1053 if (java_thread != NULL) {
1054 // This is a valid oop.
1055 jlong lp = java_lang_Thread::park_event(java_thread);
1056 if (lp != 0) {
1057 // This cast is OK even though the jlong might have been read
1058 // non-atomically on 32bit systems, since there, one word will
1059 // always be zero anyway and the value set is always the same
1060 p = (Parker*)addr_from_java(lp);
1061 } else {
1062 // Not cached in the java.lang.Thread oop yet (could be an
1063 // older version of library).
1064 if (thr != NULL) {
1065 // The JavaThread is alive.
1066 p = thr->parker();
1067 if (p != NULL) {
1068 // Cache the Parker in the java.lang.Thread oop for next time.
1069 java_lang_Thread::set_park_event(java_thread, addr_to_java(p));
1070 }
1071 }
1072 }
1073 }
1074 } // ThreadsListHandle is destroyed here.
1075
1076 if (p != NULL) {
1077 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
1078 p->unpark();
1079 }
1080 } UNSAFE_END
1081
1082 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
1083 const int max_nelem = 3;
1084 double la[max_nelem];
1085 jint ret;
1086
1087 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
1088 assert(a->is_typeArray(), "must be type array");
1089
1090 ret = os::loadavg(la, nelem);
1091 if (ret == -1) {
1092 return -1;
1093 }
1094
1095 // if successful, ret is the number of samples actually retrieved.
1096 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
1097 switch(ret) {
1098 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
1099 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
1100 case 1: a->double_at_put(0, (jdouble)la[0]); break;
1101 }
1102
1103 return ret;
1104 } UNSAFE_END
1105
1106
1107 /// JVM_RegisterUnsafeMethods
1108
1109 #define ADR "J"
1110
1111 #define LANG "Ljava/lang/"
1112
1113 #define OBJ LANG "Object;"
1114 #define CLS LANG "Class;"
1115 #define FLD LANG "reflect/Field;"
1116 #define THR LANG "Throwable;"
1117
1118 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
1119 #define DAC_Args CLS "[B[" OBJ
1120
1121 #define CC (char*) /*cast a literal from (const char*)*/
1122 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1123
1124 #define DECLARE_GETPUTOOP(Type, Desc) \
1125 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
1126 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \
1127 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
1128 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)}
1129
1130
1131 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1132 {CC "getObject", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObject)},
1133 {CC "putObject", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutObject)},
1134 {CC "getObjectVolatile",CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObjectVolatile)},
1135 {CC "putObjectVolatile",CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutObjectVolatile)},
1136
1137 {CC "isFlattenedArray", CC "(" CLS ")Z", FN_PTR(Unsafe_IsFlattenedArray)},
1138 {CC "getValue", CC "(" OBJ "J" CLS ")" OBJ "", FN_PTR(Unsafe_GetValue)},
1139 {CC "putValue", CC "(" OBJ "J" CLS OBJ ")V", FN_PTR(Unsafe_PutValue)},
1140
1141 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1142
1143 DECLARE_GETPUTOOP(Boolean, Z),
1144 DECLARE_GETPUTOOP(Byte, B),
1145 DECLARE_GETPUTOOP(Short, S),
1146 DECLARE_GETPUTOOP(Char, C),
1147 DECLARE_GETPUTOOP(Int, I),
1148 DECLARE_GETPUTOOP(Long, J),
1149 DECLARE_GETPUTOOP(Float, F),
1150 DECLARE_GETPUTOOP(Double, D),
1151
1152 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1153 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1154 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1155
1156 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1157 {CC "objectFieldOffset1", CC "(" CLS LANG "String;)J", FN_PTR(Unsafe_ObjectFieldOffset1)},
1158 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1159 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1160 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1161 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1162 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1163 {CC "addressSize0", CC "()I", FN_PTR(Unsafe_AddressSize0)},
1164 {CC "pageSize", CC "()I", FN_PTR(Unsafe_PageSize)},
1165
1166 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1167 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1168 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1169 {CC "compareAndSetObject",CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSetObject)},
1170 {CC "compareAndSetInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSetInt)},
1171 {CC "compareAndSetLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSetLong)},
1172 {CC "compareAndExchangeObject", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeObject)},
1173 {CC "compareAndExchangeInt", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)},
1174 {CC "compareAndExchangeLong", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)},
1175
1176 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1177 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1178
1179 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1180
1181 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1182 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1183 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1184
1185 {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)},
1186
1187 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1188
1189 {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)},
1190 {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)},
1191 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1192
1193 {CC "isBigEndian0", CC "()Z", FN_PTR(Unsafe_isBigEndian0)},
1194 {CC "unalignedAccess0", CC "()Z", FN_PTR(Unsafe_unalignedAccess0)}
1195 };
1196
1197 #undef CC
1198 #undef FN_PTR
1199
1200 #undef ADR
1201 #undef LANG
1202 #undef OBJ
1203 #undef CLS
1204 #undef FLD
1205 #undef THR
1206 #undef DC_Args
1207 #undef DAC_Args
1208
1209 #undef DECLARE_GETPUTOOP
1210
1211
1212 // This function is exported, used by NativeLookup.
1213 // The Unsafe_xxx functions above are called only from the interpreter.
1214 // The optimizer looks at names and signatures to recognize
1215 // individual functions.
1216
1217 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1218 ThreadToNativeFromVM ttnfv(thread);
1219
1220 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1221 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1222 } JVM_END