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 "oops/objArrayOop.inline.hpp"
30 #include "oops/oop.inline.hpp"
31 #include "prims/jni.h"
32 #include "prims/jvm.h"
33 #include "prims/unsafe.hpp"
34 #include "runtime/atomic.inline.hpp"
35 #include "runtime/globals.hpp"
36 #include "runtime/interfaceSupport.hpp"
37 #include "runtime/orderAccess.inline.hpp"
38 #include "runtime/reflection.hpp"
39 #include "runtime/vm_version.hpp"
40 #include "services/threadService.hpp"
41 #include "trace/tracing.hpp"
42 #include "utilities/copy.hpp"
43 #include "utilities/dtrace.hpp"
44 #include "utilities/macros.hpp"
45 #if INCLUDE_ALL_GCS
46 #include "gc/shared/satbMarkQueue.hpp"
47 #endif // INCLUDE_ALL_GCS
48
49 /**
50 * Implementation of the jdk.internal.misc.Unsafe class
51 */
52
53
54 #define MAX_OBJECT_SIZE \
55 ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
56 + ((julong)max_jint * sizeof(double)) )
57
58
59 #define UNSAFE_ENTRY(result_type, header) \
60 JVM_ENTRY(static result_type, header)
61
62 #define UNSAFE_LEAF(result_type, header) \
63 JVM_LEAF(static result_type, header)
64
65 #define UNSAFE_END JVM_END
66
67
68 static inline void* addr_from_java(jlong addr) {
69 // This assert fails in a variety of ways on 32-bit systems.
70 // It is impossible to predict whether native code that converts
71 // pointers to longs will sign-extend or zero-extend the addresses.
72 //assert(addr == (uintptr_t)addr, "must not be odd high bits");
73 return (void*)(uintptr_t)addr;
74 }
75
76 static inline jlong addr_to_java(void* p) {
77 assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
78 return (uintptr_t)p;
79 }
80
81
82 // Note: The VM's obj_field and related accessors use byte-scaled
83 // ("unscaled") offsets, just as the unsafe methods do.
84
85 // However, the method Unsafe.fieldOffset explicitly declines to
86 // guarantee this. The field offset values manipulated by the Java user
87 // through the Unsafe API are opaque cookies that just happen to be byte
88 // offsets. We represent this state of affairs by passing the cookies
89 // through conversion functions when going between the VM and the Unsafe API.
90 // The conversion functions just happen to be no-ops at present.
91
92 static inline jlong field_offset_to_byte_offset(jlong field_offset) {
93 return field_offset;
94 }
95
96 static inline jlong field_offset_from_byte_offset(jlong byte_offset) {
97 return byte_offset;
98 }
99
100 static inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
101 jlong byte_offset = field_offset_to_byte_offset(field_offset);
102
103 #ifdef ASSERT
104 if (p != NULL) {
105 assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
106 if (byte_offset == (jint)byte_offset) {
107 void* ptr_plus_disp = (address)p + byte_offset;
108 assert((void*)p->obj_field_addr<oop>((jint)byte_offset) == ptr_plus_disp,
109 "raw [ptr+disp] must be consistent with oop::field_base");
110 }
111 jlong p_size = HeapWordSize * (jlong)(p->size());
112 assert(byte_offset < p_size, "Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, byte_offset, p_size);
113 }
114 #endif
115
116 if (sizeof(char*) == sizeof(jint)) { // (this constant folds!)
117 return (address)p + (jint) byte_offset;
118 } else {
119 return (address)p + byte_offset;
120 }
121 }
122
123 // Externally callable versions:
124 // (Use these in compiler intrinsics which emulate unsafe primitives.)
125 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
126 return field_offset;
127 }
128 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
129 return byte_offset;
130 }
131
132
133 ///// Data in the Java heap.
134
135 #define GET_FIELD(obj, offset, type_name, v) \
136 oop p = JNIHandles::resolve(obj); \
137 type_name v = *(type_name*)index_oop_from_field_offset_long(p, offset)
138
139 #define SET_FIELD(obj, offset, type_name, x) \
140 oop p = JNIHandles::resolve(obj); \
141 *(type_name*)index_oop_from_field_offset_long(p, offset) = x
142
143 #define GET_FIELD_VOLATILE(obj, offset, type_name, v) \
144 oop p = JNIHandles::resolve(obj); \
145 if (support_IRIW_for_not_multiple_copy_atomic_cpu) { \
146 OrderAccess::fence(); \
147 } \
148 volatile type_name v = OrderAccess::load_acquire((volatile type_name*)index_oop_from_field_offset_long(p, offset));
149
150 #define SET_FIELD_VOLATILE(obj, offset, type_name, x) \
151 oop p = JNIHandles::resolve(obj); \
152 OrderAccess::release_store_fence((volatile type_name*)index_oop_from_field_offset_long(p, offset), x);
153
154
155 // Get/SetObject must be special-cased, since it works with handles.
156
157 // These functions allow a null base pointer with an arbitrary address.
158 // But if the base pointer is non-null, the offset should make some sense.
159 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
160 UNSAFE_ENTRY(jobject, Unsafe_GetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
161 oop p = JNIHandles::resolve(obj);
162 oop v;
163
164 if (UseCompressedOops) {
165 narrowOop n = *(narrowOop*)index_oop_from_field_offset_long(p, offset);
166 v = oopDesc::decode_heap_oop(n);
167 } else {
168 v = *(oop*)index_oop_from_field_offset_long(p, offset);
169 }
170
171 jobject ret = JNIHandles::make_local(env, v);
172
173 #if INCLUDE_ALL_GCS
174 // We could be accessing the referent field in a reference
175 // object. If G1 is enabled then we need to register non-null
176 // referent with the SATB barrier.
177 if (UseG1GC) {
178 bool needs_barrier = false;
179
180 if (ret != NULL) {
181 if (offset == java_lang_ref_Reference::referent_offset && obj != NULL) {
182 oop o = JNIHandles::resolve(obj);
183 Klass* k = o->klass();
184 if (InstanceKlass::cast(k)->reference_type() != REF_NONE) {
185 assert(InstanceKlass::cast(k)->is_subclass_of(SystemDictionary::Reference_klass()), "sanity");
186 needs_barrier = true;
187 }
188 }
189 }
190
191 if (needs_barrier) {
192 oop referent = JNIHandles::resolve(ret);
193 SATBMarkQueue::enqueue(referent);
194 }
195 }
196 #endif // INCLUDE_ALL_GCS
197
198 return ret;
199 } UNSAFE_END
200
201 UNSAFE_ENTRY(void, Unsafe_SetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
202 oop x = JNIHandles::resolve(x_h);
203 oop p = JNIHandles::resolve(obj);
204
205 if (UseCompressedOops) {
206 oop_store((narrowOop*)index_oop_from_field_offset_long(p, offset), x);
207 } else {
208 oop_store((oop*)index_oop_from_field_offset_long(p, offset), x);
209 }
210 } UNSAFE_END
211
212 UNSAFE_ENTRY(jobject, Unsafe_GetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
213 oop p = JNIHandles::resolve(obj);
214 void* addr = index_oop_from_field_offset_long(p, offset);
215
216 volatile oop v;
217
218 if (UseCompressedOops) {
219 volatile narrowOop n = *(volatile narrowOop*) addr;
220 (void)const_cast<oop&>(v = oopDesc::decode_heap_oop(n));
221 } else {
222 (void)const_cast<oop&>(v = *(volatile oop*) addr);
223 }
224
225 OrderAccess::acquire();
226 return JNIHandles::make_local(env, v);
227 } UNSAFE_END
228
229 UNSAFE_ENTRY(void, Unsafe_SetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
230 oop x = JNIHandles::resolve(x_h);
231 oop p = JNIHandles::resolve(obj);
232 void* addr = index_oop_from_field_offset_long(p, offset);
233 OrderAccess::release();
234
235 if (UseCompressedOops) {
236 oop_store((narrowOop*)addr, x);
237 } else {
238 oop_store((oop*)addr, x);
239 }
240
241 OrderAccess::fence();
242 } UNSAFE_END
243
244 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) {
245 oop v = *(oop*) (address) addr;
246
247 return JNIHandles::make_local(env, v);
248 } UNSAFE_END
249
250 UNSAFE_ENTRY(jclass, Unsafe_GetJavaMirror(JNIEnv *env, jobject unsafe, jlong metaspace_klass)) {
251 Klass* klass = (Klass*) (address) metaspace_klass;
252
253 return (jclass) JNIHandles::make_local(klass->java_mirror());
254 } UNSAFE_END
255
256 UNSAFE_ENTRY(jlong, Unsafe_GetKlassPointer(JNIEnv *env, jobject unsafe, jobject obj)) {
257 oop o = JNIHandles::resolve(obj);
258 jlong klass = (jlong) (address) o->klass();
259
260 return klass;
261 } UNSAFE_END
262
263 #ifndef SUPPORTS_NATIVE_CX8
264
265 // VM_Version::supports_cx8() is a surrogate for 'supports atomic long memory ops'.
266 //
267 // On platforms which do not support atomic compare-and-swap of jlong (8 byte)
268 // values we have to use a lock-based scheme to enforce atomicity. This has to be
269 // applied to all Unsafe operations that set the value of a jlong field. Even so
270 // the compareAndSwapLong operation will not be atomic with respect to direct stores
271 // to the field from Java code. It is important therefore that any Java code that
272 // utilizes these Unsafe jlong operations does not perform direct stores. To permit
273 // direct loads of the field from Java code we must also use Atomic::store within the
274 // locked regions. And for good measure, in case there are direct stores, we also
275 // employ Atomic::load within those regions. Note that the field in question must be
276 // volatile and so must have atomic load/store accesses applied at the Java level.
277 //
278 // The locking scheme could utilize a range of strategies for controlling the locking
279 // granularity: from a lock per-field through to a single global lock. The latter is
280 // the simplest and is used for the current implementation. Note that the Java object
281 // that contains the field, can not, in general, be used for locking. To do so can lead
282 // to deadlocks as we may introduce locking into what appears to the Java code to be a
283 // lock-free path.
284 //
285 // As all the locked-regions are very short and themselves non-blocking we can treat
286 // them as leaf routines and elide safepoint checks (ie we don't perform any thread
287 // state transitions even when blocking for the lock). Note that if we do choose to
288 // add safepoint checks and thread state transitions, we must ensure that we calculate
289 // the address of the field _after_ we have acquired the lock, else the object may have
290 // been moved by the GC
291
292 UNSAFE_ENTRY(jlong, Unsafe_GetLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) {
293 if (VM_Version::supports_cx8()) {
294 GET_FIELD_VOLATILE(obj, offset, jlong, v);
295 return v;
296 } else {
297 Handle p (THREAD, JNIHandles::resolve(obj));
298 jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
299 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
300 jlong value = Atomic::load(addr);
301 return value;
302 }
303 } UNSAFE_END
304
305 UNSAFE_ENTRY(void, Unsafe_SetLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong x)) {
306 if (VM_Version::supports_cx8()) {
307 SET_FIELD_VOLATILE(obj, offset, jlong, x);
308 } else {
309 Handle p (THREAD, JNIHandles::resolve(obj));
310 jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
311 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
312 Atomic::store(x, addr);
313 }
314 } UNSAFE_END
315
316 #endif // not SUPPORTS_NATIVE_CX8
317
318 UNSAFE_LEAF(jboolean, Unsafe_isBigEndian0(JNIEnv *env, jobject unsafe)) {
319 #ifdef VM_LITTLE_ENDIAN
320 return false;
321 #else
322 return true;
323 #endif
324 } UNSAFE_END
325
326 UNSAFE_LEAF(jint, Unsafe_unalignedAccess0(JNIEnv *env, jobject unsafe)) {
327 return UseUnalignedAccesses;
328 } UNSAFE_END
329
330 #define DEFINE_GETSETOOP(java_type, Type) \
331 \
332 UNSAFE_ENTRY(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
333 GET_FIELD(obj, offset, java_type, v); \
334 return v; \
335 } UNSAFE_END \
336 \
337 UNSAFE_ENTRY(void, Unsafe_Set##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
338 SET_FIELD(obj, offset, java_type, x); \
339 } UNSAFE_END \
340 \
341 // END DEFINE_GETSETOOP.
342
343 DEFINE_GETSETOOP(jboolean, Boolean)
344 DEFINE_GETSETOOP(jbyte, Byte)
345 DEFINE_GETSETOOP(jshort, Short);
346 DEFINE_GETSETOOP(jchar, Char);
347 DEFINE_GETSETOOP(jint, Int);
348 DEFINE_GETSETOOP(jlong, Long);
349 DEFINE_GETSETOOP(jfloat, Float);
350 DEFINE_GETSETOOP(jdouble, Double);
351
352 #undef DEFINE_GETSETOOP
353
354 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \
355 \
356 UNSAFE_ENTRY(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \
357 GET_FIELD_VOLATILE(obj, offset, java_type, v); \
358 return v; \
359 } UNSAFE_END \
360 \
361 UNSAFE_ENTRY(void, Unsafe_Set##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \
362 SET_FIELD_VOLATILE(obj, offset, java_type, x); \
363 } UNSAFE_END \
364 \
365 // END DEFINE_GETSETOOP_VOLATILE.
366
367 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
368 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
369 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
370 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
371 DEFINE_GETSETOOP_VOLATILE(jint, Int);
372 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
373 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
374
375 #ifdef SUPPORTS_NATIVE_CX8
376 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
377 #endif
378
379 #undef DEFINE_GETSETOOP_VOLATILE
380
381 UNSAFE_LEAF(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe)) {
382 OrderAccess::acquire();
383 } UNSAFE_END
384
385 UNSAFE_LEAF(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe)) {
386 OrderAccess::release();
387 } UNSAFE_END
388
389 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
390 OrderAccess::fence();
391 } UNSAFE_END
392
393 ////// Data in the C heap.
394
395 // Note: These do not throw NullPointerException for bad pointers.
396 // They just crash. Only a oop base pointer can generate a NullPointerException.
397 //
398 #define DEFINE_GETSETNATIVE(java_type, Type, native_type) \
399 \
400 UNSAFE_ENTRY(java_type, Unsafe_GetNative##Type(JNIEnv *env, jobject unsafe, jlong addr)) { \
401 void* p = addr_from_java(addr); \
402 JavaThread* t = JavaThread::current(); \
403 t->set_doing_unsafe_access(true); \
404 java_type x = *(volatile native_type*)p; \
405 t->set_doing_unsafe_access(false); \
406 return x; \
407 } UNSAFE_END \
408 \
409 UNSAFE_ENTRY(void, Unsafe_SetNative##Type(JNIEnv *env, jobject unsafe, jlong addr, java_type x)) { \
410 JavaThread* t = JavaThread::current(); \
411 t->set_doing_unsafe_access(true); \
412 void* p = addr_from_java(addr); \
413 *(volatile native_type*)p = x; \
414 t->set_doing_unsafe_access(false); \
415 } UNSAFE_END \
416 \
417 // END DEFINE_GETSETNATIVE.
418
419 DEFINE_GETSETNATIVE(jbyte, Byte, signed char)
420 DEFINE_GETSETNATIVE(jshort, Short, signed short);
421 DEFINE_GETSETNATIVE(jchar, Char, unsigned short);
422 DEFINE_GETSETNATIVE(jint, Int, jint);
423 // no long -- handled specially
424 DEFINE_GETSETNATIVE(jfloat, Float, float);
425 DEFINE_GETSETNATIVE(jdouble, Double, double);
426
427 #undef DEFINE_GETSETNATIVE
428
429 UNSAFE_ENTRY(jlong, Unsafe_GetNativeLong(JNIEnv *env, jobject unsafe, jlong addr)) {
430 JavaThread* t = JavaThread::current();
431 // We do it this way to avoid problems with access to heap using 64
432 // bit loads, as jlong in heap could be not 64-bit aligned, and on
433 // some CPUs (SPARC) it leads to SIGBUS.
434 t->set_doing_unsafe_access(true);
435 void* p = addr_from_java(addr);
436 jlong x;
437
438 if (is_ptr_aligned(p, sizeof(jlong)) == 0) {
439 // jlong is aligned, do a volatile access
440 x = *(volatile jlong*)p;
441 } else {
442 jlong_accessor acc;
443 acc.words[0] = ((volatile jint*)p)[0];
444 acc.words[1] = ((volatile jint*)p)[1];
445 x = acc.long_value;
446 }
447
448 t->set_doing_unsafe_access(false);
449
450 return x;
451 } UNSAFE_END
452
453 UNSAFE_ENTRY(void, Unsafe_SetNativeLong(JNIEnv *env, jobject unsafe, jlong addr, jlong x)) {
454 JavaThread* t = JavaThread::current();
455 // see comment for Unsafe_GetNativeLong
456 t->set_doing_unsafe_access(true);
457 void* p = addr_from_java(addr);
458
459 if (is_ptr_aligned(p, sizeof(jlong))) {
460 // jlong is aligned, do a volatile access
461 *(volatile jlong*)p = x;
462 } else {
463 jlong_accessor acc;
464 acc.long_value = x;
465 ((volatile jint*)p)[0] = acc.words[0];
466 ((volatile jint*)p)[1] = acc.words[1];
467 }
468
469 t->set_doing_unsafe_access(false);
470 } UNSAFE_END
471
472
473 UNSAFE_LEAF(jlong, Unsafe_GetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr)) {
474 void* p = addr_from_java(addr);
475
476 return addr_to_java(*(void**)p);
477 } UNSAFE_END
478
479 UNSAFE_LEAF(void, Unsafe_SetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr, jlong x)) {
480 void* p = addr_from_java(addr);
481 *(void**)p = addr_from_java(x);
482 } UNSAFE_END
483
484
485 ////// Allocation requests
486
487 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
488 ThreadToNativeFromVM ttnfv(thread);
489 return env->AllocObject(cls);
490 } UNSAFE_END
491
492 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) {
493 size_t sz = (size_t)size;
494
495 sz = round_to(sz, HeapWordSize);
496 void* x = os::malloc(sz, mtInternal);
497
498 return addr_to_java(x);
499 } UNSAFE_END
500
501 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) {
502 void* p = addr_from_java(addr);
503 size_t sz = (size_t)size;
504 sz = round_to(sz, HeapWordSize);
505
506 void* x = os::realloc(p, sz, mtInternal);
507
508 return addr_to_java(x);
509 } UNSAFE_END
510
511 UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) {
512 void* p = addr_from_java(addr);
513
514 os::free(p);
515 } UNSAFE_END
516
517 UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) {
518 size_t sz = (size_t)size;
519
520 oop base = JNIHandles::resolve(obj);
521 void* p = index_oop_from_field_offset_long(base, offset);
522
523 Copy::fill_to_memory_atomic(p, sz, value);
524 } UNSAFE_END
525
526 UNSAFE_ENTRY(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) {
527 size_t sz = (size_t)size;
528
529 oop srcp = JNIHandles::resolve(srcObj);
530 oop dstp = JNIHandles::resolve(dstObj);
531
532 void* src = index_oop_from_field_offset_long(srcp, srcOffset);
533 void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
534
535 Copy::conjoint_memory_atomic(src, dst, sz);
536 } UNSAFE_END
537
538 // This function is a leaf since if the source and destination are both in native memory
539 // the copy may potentially be very large, and we don't want to disable GC if we can avoid it.
540 // If either source or destination (or both) are on the heap, the function will enter VM using
541 // JVM_ENTRY_FROM_LEAF
542 UNSAFE_LEAF(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) {
543 size_t sz = (size_t)size;
544 size_t esz = (size_t)elemSize;
545
546 if (srcObj == NULL && dstObj == NULL) {
547 // Both src & dst are in native memory
548 address src = (address)srcOffset;
549 address dst = (address)dstOffset;
550
551 Copy::conjoint_swap(src, dst, sz, esz);
552 } else {
553 // At least one of src/dst are on heap, transition to VM to access raw pointers
554
555 JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) {
556 oop srcp = JNIHandles::resolve(srcObj);
557 oop dstp = JNIHandles::resolve(dstObj);
558
559 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset);
560 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset);
561
562 Copy::conjoint_swap(src, dst, sz, esz);
563 } JVM_END
564 }
565 } UNSAFE_END
566
567 ////// Random queries
568
569 UNSAFE_LEAF(jint, Unsafe_AddressSize0(JNIEnv *env, jobject unsafe)) {
570 return sizeof(void*);
571 } UNSAFE_END
572
573 UNSAFE_LEAF(jint, Unsafe_PageSize()) {
574 return os::vm_page_size();
575 } UNSAFE_END
576
577 static jint find_field_offset(jobject field, int must_be_static, TRAPS) {
578 assert(field != NULL, "field must not be NULL");
579
580 oop reflected = JNIHandles::resolve_non_null(field);
581 oop mirror = java_lang_reflect_Field::clazz(reflected);
582 Klass* k = java_lang_Class::as_Klass(mirror);
583 int slot = java_lang_reflect_Field::slot(reflected);
584 int modifiers = java_lang_reflect_Field::modifiers(reflected);
585
586 if (must_be_static >= 0) {
587 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
588 if (must_be_static != really_is_static) {
589 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
590 }
591 }
592
593 int offset = InstanceKlass::cast(k)->field_offset(slot);
594 return field_offset_from_byte_offset(offset);
595 }
596
597 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
598 return find_field_offset(field, 0, THREAD);
599 } UNSAFE_END
600
601 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
602 return find_field_offset(field, 1, THREAD);
603 } UNSAFE_END
604
605 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) {
606 assert(field != NULL, "field must not be NULL");
607
608 // Note: In this VM implementation, a field address is always a short
609 // offset from the base of a a klass metaobject. Thus, the full dynamic
610 // range of the return type is never used. However, some implementations
611 // might put the static field inside an array shared by many classes,
612 // or even at a fixed address, in which case the address could be quite
613 // large. In that last case, this function would return NULL, since
614 // the address would operate alone, without any base pointer.
615
616 oop reflected = JNIHandles::resolve_non_null(field);
617 oop mirror = java_lang_reflect_Field::clazz(reflected);
618 int modifiers = java_lang_reflect_Field::modifiers(reflected);
619
620 if ((modifiers & JVM_ACC_STATIC) == 0) {
621 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
622 }
623
624 return JNIHandles::make_local(env, mirror);
625 } UNSAFE_END
626
627 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
628 assert(clazz != NULL, "clazz must not be NULL");
629
630 oop mirror = JNIHandles::resolve_non_null(clazz);
631
632 Klass* klass = java_lang_Class::as_Klass(mirror);
633 if (klass != NULL && klass->should_be_initialized()) {
634 InstanceKlass* k = InstanceKlass::cast(klass);
635 k->initialize(CHECK);
636 }
637 }
638 UNSAFE_END
639
640 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
641 assert(clazz != NULL, "clazz must not be NULL");
642
643 oop mirror = JNIHandles::resolve_non_null(clazz);
644 Klass* klass = java_lang_Class::as_Klass(mirror);
645
646 if (klass != NULL && klass->should_be_initialized()) {
647 return true;
648 }
649
650 return false;
651 }
652 UNSAFE_END
653
654 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) {
655 assert(clazz != NULL, "clazz must not be NULL");
656
657 oop mirror = JNIHandles::resolve_non_null(clazz);
658 Klass* k = java_lang_Class::as_Klass(mirror);
659
660 if (k == NULL || !k->is_array_klass()) {
661 THROW(vmSymbols::java_lang_InvalidClassException());
662 } else if (k->is_objArray_klass()) {
663 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
664 scale = heapOopSize;
665 } else if (k->is_typeArray_klass()) {
666 TypeArrayKlass* tak = TypeArrayKlass::cast(k);
667 base = tak->array_header_in_bytes();
668 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
669 scale = (1 << tak->log2_element_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 char buf[100];
707
708 jio_snprintf(buf, 100, "%s%s", "java/lang/", ename);
709
710 jclass cls = env->FindClass(buf);
711 if (env->ExceptionCheck()) {
712 env->ExceptionClear();
713 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", buf);
714 return;
715 }
716
717 env->ThrowNew(cls, NULL);
718 }
719
720 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
721 // Code lifted from JDK 1.3 ClassLoader.c
722
723 jbyte *body;
724 char *utfName = NULL;
725 jclass result = 0;
726 char buf[128];
727
728 assert(data != NULL, "Class bytes must not be NULL");
729 assert(length >= 0, "length must not be negative: %d", length);
730
731 if (UsePerfData) {
732 ClassLoader::unsafe_defineClassCallCounter()->inc();
733 }
734
735 body = NEW_C_HEAP_ARRAY(jbyte, length, mtInternal);
736 if (body == NULL) {
737 throw_new(env, "OutOfMemoryError");
738 return 0;
739 }
740
741 env->GetByteArrayRegion(data, offset, length, body);
742 if (env->ExceptionOccurred()) {
743 goto free_body;
744 }
745
746 if (name != NULL) {
747 uint len = env->GetStringUTFLength(name);
748 int unicode_len = env->GetStringLength(name);
749
750 if (len >= sizeof(buf)) {
751 utfName = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
752 if (utfName == NULL) {
753 throw_new(env, "OutOfMemoryError");
754 goto free_body;
755 }
756 } else {
757 utfName = buf;
758 }
759
760 env->GetStringUTFRegion(name, 0, unicode_len, utfName);
761
762 for (uint i = 0; i < len; i++) {
763 if (utfName[i] == '.') utfName[i] = '/';
764 }
765 }
766
767 result = JVM_DefineClass(env, utfName, loader, body, length, pd);
768
769 if (utfName && utfName != buf) {
770 FREE_C_HEAP_ARRAY(char, utfName);
771 }
772
773 free_body:
774 FREE_C_HEAP_ARRAY(jbyte, body);
775 return result;
776 }
777
778
779 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) {
780 ThreadToNativeFromVM ttnfv(thread);
781
782 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
783 } UNSAFE_END
784
785
786 // define a class but do not make it known to the class loader or system dictionary
787 // - host_class: supplies context for linkage, access control, protection domain, and class loader
788 // - data: bytes of a class file, a raw memory address (length gives the number of bytes)
789 // - cp_patches: where non-null entries exist, they replace corresponding CP entries in data
790
791 // When you load an anonymous class U, it works as if you changed its name just before loading,
792 // to a name that you will never use again. Since the name is lost, no other class can directly
793 // link to any member of U. Just after U is loaded, the only way to use it is reflectively,
794 // through java.lang.Class methods like Class.newInstance.
795
796 // Access checks for linkage sites within U continue to follow the same rules as for named classes.
797 // The package of an anonymous class is given by the package qualifier on the name under which it was loaded.
798 // An anonymous class also has special privileges to access any member of its host class.
799 // This is the main reason why this loading operation is unsafe. The purpose of this is to
800 // allow language implementations to simulate "open classes"; a host class in effect gets
801 // new code when an anonymous class is loaded alongside it. A less convenient but more
802 // standard way to do this is with reflection, which can also be set to ignore access
803 // restrictions.
804
805 // Access into an anonymous class is possible only through reflection. Therefore, there
806 // are no special access rules for calling into an anonymous class. The relaxed access
807 // rule for the host class is applied in the opposite direction: A host class reflectively
808 // access one of its anonymous classes.
809
810 // If you load the same bytecodes twice, you get two different classes. You can reload
811 // the same bytecodes with or without varying CP patches.
812
813 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
814 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
815 // The CONSTANT_Class entry for that name can be patched to refer directly to U1.
816
817 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as
818 // an outer class (so that U2 is an anonymous inner class of anonymous U1).
819 // It is not possible for a named class, or an older anonymous class, to refer by
820 // name (via its CP) to a newer anonymous class.
821
822 // CP patching may also be used to modify (i.e., hack) the names of methods, classes,
823 // or type descriptors used in the loaded anonymous class.
824
825 // Finally, CP patching may be used to introduce "live" objects into the constant pool,
826 // instead of "dead" strings. A compiled statement like println((Object)"hello") can
827 // be changed to println(greeting), where greeting is an arbitrary object created before
828 // the anonymous class is loaded. This is useful in dynamic languages, in which
829 // various kinds of metaobjects must be introduced as constants into bytecode.
830 // Note the cast (Object), which tells the verifier to expect an arbitrary object,
831 // not just a literal string. For such ldc instructions, the verifier uses the
832 // type Object instead of String, if the loaded constant is not in fact a String.
833
834 static instanceKlassHandle
835 Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
836 jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
837 u1** temp_alloc,
838 TRAPS) {
839 assert(host_class != NULL, "host_class must not be NULL");
840 assert(data != NULL, "data must not be NULL");
841
842 if (UsePerfData) {
843 ClassLoader::unsafe_defineClassCallCounter()->inc();
844 }
845
846 jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
847 assert(length >= 0, "class_bytes_length must not be negative: %d", length);
848
849 int class_bytes_length = (int) length;
850
851 u1* class_bytes = NEW_C_HEAP_ARRAY(u1, length, mtInternal);
852 if (class_bytes == NULL) {
853 THROW_0(vmSymbols::java_lang_OutOfMemoryError());
854 }
855
856 // caller responsible to free it:
857 *temp_alloc = class_bytes;
858
859 jbyte* array_base = typeArrayOop(JNIHandles::resolve_non_null(data))->byte_at_addr(0);
860 Copy::conjoint_jbytes(array_base, class_bytes, length);
861
862 objArrayHandle cp_patches_h;
863 if (cp_patches_jh != NULL) {
864 oop p = JNIHandles::resolve_non_null(cp_patches_jh);
865 assert(p->is_objArray(), "cp_patches must be an object[]");
866 cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
867 }
868
869 const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class));
870 assert(host_klass != NULL, "invariant");
871
872 const char* host_source = host_klass->external_name();
873 Handle host_loader(THREAD, host_klass->class_loader());
874 Handle host_domain(THREAD, host_klass->protection_domain());
875
876 GrowableArray<Handle>* cp_patches = NULL;
877
878 if (cp_patches_h.not_null()) {
879 int alen = cp_patches_h->length();
880
881 for (int i = alen-1; i >= 0; i--) {
882 oop p = cp_patches_h->obj_at(i);
883 if (p != NULL) {
884 Handle patch(THREAD, p);
885
886 if (cp_patches == NULL) {
887 cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
888 }
889
890 cp_patches->at_put(i, patch);
891 }
892 }
893 }
894
895 ClassFileStream st(class_bytes, class_bytes_length, host_source, ClassFileStream::verify);
896
897 Symbol* no_class_name = NULL;
898 Klass* anonk = SystemDictionary::parse_stream(no_class_name,
899 host_loader,
900 host_domain,
901 &st,
902 host_klass,
903 cp_patches,
904 CHECK_NULL);
905 if (anonk == NULL) {
906 return NULL;
907 }
908
909 return instanceKlassHandle(THREAD, anonk);
910 }
911
912 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) {
913 ResourceMark rm(THREAD);
914
915 instanceKlassHandle anon_klass;
916 jobject res_jh = NULL;
917 u1* temp_alloc = NULL;
918
919 anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data, cp_patches_jh, &temp_alloc, THREAD);
920 if (anon_klass() != NULL) {
921 res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
922 }
923
924 // try/finally clause:
925 if (temp_alloc != NULL) {
926 FREE_C_HEAP_ARRAY(u1, temp_alloc);
927 }
928
929 // The anonymous class loader data has been artificially been kept alive to
930 // this point. The mirror and any instances of this class have to keep
931 // it alive afterwards.
932 if (anon_klass() != NULL) {
933 anon_klass->class_loader_data()->set_keep_alive(false);
934 }
935
936 // let caller initialize it as needed...
937
938 return (jclass) res_jh;
939 } UNSAFE_END
940
941
942
943 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
944 ThreadToNativeFromVM ttnfv(thread);
945 env->Throw(thr);
946 } UNSAFE_END
947
948 // JSR166 ------------------------------------------------------------------
949
950 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
951 oop x = JNIHandles::resolve(x_h);
952 oop e = JNIHandles::resolve(e_h);
953 oop p = JNIHandles::resolve(obj);
954 HeapWord* addr = (HeapWord *)index_oop_from_field_offset_long(p, offset);
955 oop res = oopDesc::atomic_compare_exchange_oop(x, addr, e, true);
956 if (res == e) {
957 update_barrier_set((void*)addr, x);
958 }
959 return JNIHandles::make_local(env, res);
960 } UNSAFE_END
961
962 UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
963 oop p = JNIHandles::resolve(obj);
964 jint* addr = (jint *) index_oop_from_field_offset_long(p, offset);
965
966 return (jint)(Atomic::cmpxchg(x, addr, e));
967 } UNSAFE_END
968
969 UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
970 Handle p (THREAD, JNIHandles::resolve(obj));
971 jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
972
973 #ifdef SUPPORTS_NATIVE_CX8
974 return (jlong)(Atomic::cmpxchg(x, addr, e));
975 #else
976 if (VM_Version::supports_cx8()) {
977 return (jlong)(Atomic::cmpxchg(x, addr, e));
978 } else {
979 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
980
981 jlong val = Atomic::load(addr);
982 if (val == e) {
983 Atomic::store(x, addr);
984 }
985 return val;
986 }
987 #endif
988 } UNSAFE_END
989
990 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
991 oop x = JNIHandles::resolve(x_h);
992 oop e = JNIHandles::resolve(e_h);
993 oop p = JNIHandles::resolve(obj);
994 HeapWord* addr = (HeapWord *)index_oop_from_field_offset_long(p, offset);
995 oop res = oopDesc::atomic_compare_exchange_oop(x, addr, e, true);
996 if (res != e) {
997 return false;
998 }
999
1000 update_barrier_set((void*)addr, x);
1001
1002 return true;
1003 } UNSAFE_END
1004
1005 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
1006 oop p = JNIHandles::resolve(obj);
1007 jint* addr = (jint *) index_oop_from_field_offset_long(p, offset);
1008
1009 return (jint)(Atomic::cmpxchg(x, addr, e)) == e;
1010 } UNSAFE_END
1011
1012 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
1013 Handle p(THREAD, JNIHandles::resolve(obj));
1014 jlong* addr = (jlong*)index_oop_from_field_offset_long(p(), offset);
1015
1016 #ifdef SUPPORTS_NATIVE_CX8
1017 return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
1018 #else
1019 if (VM_Version::supports_cx8()) {
1020 return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
1021 } else {
1022 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
1023
1024 jlong val = Atomic::load(addr);
1025 if (val != e) {
1026 return false;
1027 }
1028
1029 Atomic::store(x, addr);
1030 return true;
1031 }
1032 #endif
1033 } UNSAFE_END
1034
1035 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
1036 EventThreadPark event;
1037 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
1038
1039 JavaThreadParkedState jtps(thread, time != 0);
1040 thread->parker()->park(isAbsolute != 0, time);
1041
1042 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
1043
1044 if (event.should_commit()) {
1045 oop obj = thread->current_park_blocker();
1046 event.set_klass((obj != NULL) ? obj->klass() : NULL);
1047 event.set_timeout(time);
1048 event.set_address((obj != NULL) ? (TYPE_ADDRESS) cast_from_oop<uintptr_t>(obj) : 0);
1049 event.commit();
1050 }
1051 } UNSAFE_END
1052
1053 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
1054 Parker* p = NULL;
1055
1056 if (jthread != NULL) {
1057 oop java_thread = JNIHandles::resolve_non_null(jthread);
1058 if (java_thread != NULL) {
1059 jlong lp = java_lang_Thread::park_event(java_thread);
1060 if (lp != 0) {
1061 // This cast is OK even though the jlong might have been read
1062 // non-atomically on 32bit systems, since there, one word will
1063 // always be zero anyway and the value set is always the same
1064 p = (Parker*)addr_from_java(lp);
1065 } else {
1066 // Grab lock if apparently null or using older version of library
1067 MutexLocker mu(Threads_lock);
1068 java_thread = JNIHandles::resolve_non_null(jthread);
1069
1070 if (java_thread != NULL) {
1071 JavaThread* thr = java_lang_Thread::thread(java_thread);
1072 if (thr != NULL) {
1073 p = thr->parker();
1074 if (p != NULL) { // Bind to Java thread for next time.
1075 java_lang_Thread::set_park_event(java_thread, addr_to_java(p));
1076 }
1077 }
1078 }
1079 }
1080 }
1081 }
1082
1083 if (p != NULL) {
1084 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
1085 p->unpark();
1086 }
1087 } UNSAFE_END
1088
1089 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
1090 const int max_nelem = 3;
1091 double la[max_nelem];
1092 jint ret;
1093
1094 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
1095 assert(a->is_typeArray(), "must be type array");
1096
1097 ret = os::loadavg(la, nelem);
1098 if (ret == -1) {
1099 return -1;
1100 }
1101
1102 // if successful, ret is the number of samples actually retrieved.
1103 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
1104 switch(ret) {
1105 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
1106 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
1107 case 1: a->double_at_put(0, (jdouble)la[0]); break;
1108 }
1109
1110 return ret;
1111 } UNSAFE_END
1112
1113
1114 /// JVM_RegisterUnsafeMethods
1115
1116 #define ADR "J"
1117
1118 #define LANG "Ljava/lang/"
1119
1120 #define OBJ LANG "Object;"
1121 #define CLS LANG "Class;"
1122 #define FLD LANG "reflect/Field;"
1123 #define THR LANG "Throwable;"
1124
1125 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
1126 #define DAC_Args CLS "[B[" OBJ
1127
1128 #define CC (char*) /*cast a literal from (const char*)*/
1129 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1130
1131 #define DECLARE_GETPUTOOP(Type, Desc) \
1132 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
1133 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Set##Type)}, \
1134 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
1135 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Set##Type##Volatile)}
1136
1137
1138 #define DECLARE_GETPUTNATIVE(Byte, B) \
1139 {CC "get" #Byte, CC "(" ADR ")" #B, FN_PTR(Unsafe_GetNative##Byte)}, \
1140 {CC "put" #Byte, CC "(" ADR#B ")V", FN_PTR(Unsafe_SetNative##Byte)}
1141
1142 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1143 {CC "getObject", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObject)},
1144 {CC "putObject", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_SetObject)},
1145 {CC "getObjectVolatile",CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObjectVolatile)},
1146 {CC "putObjectVolatile",CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_SetObjectVolatile)},
1147
1148 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1149 {CC "getJavaMirror", CC "(" ADR ")" CLS, FN_PTR(Unsafe_GetJavaMirror)},
1150 {CC "getKlassPointer", CC "(" OBJ ")" ADR, FN_PTR(Unsafe_GetKlassPointer)},
1151
1152 DECLARE_GETPUTOOP(Boolean, Z),
1153 DECLARE_GETPUTOOP(Byte, B),
1154 DECLARE_GETPUTOOP(Short, S),
1155 DECLARE_GETPUTOOP(Char, C),
1156 DECLARE_GETPUTOOP(Int, I),
1157 DECLARE_GETPUTOOP(Long, J),
1158 DECLARE_GETPUTOOP(Float, F),
1159 DECLARE_GETPUTOOP(Double, D),
1160
1161 DECLARE_GETPUTNATIVE(Byte, B),
1162 DECLARE_GETPUTNATIVE(Short, S),
1163 DECLARE_GETPUTNATIVE(Char, C),
1164 DECLARE_GETPUTNATIVE(Int, I),
1165 DECLARE_GETPUTNATIVE(Long, J),
1166 DECLARE_GETPUTNATIVE(Float, F),
1167 DECLARE_GETPUTNATIVE(Double, D),
1168
1169 {CC "getAddress", CC "(" ADR ")" ADR, FN_PTR(Unsafe_GetNativeAddress)},
1170 {CC "putAddress", CC "(" ADR "" ADR ")V", FN_PTR(Unsafe_SetNativeAddress)},
1171
1172 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1173 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1174 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1175
1176 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1177 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1178 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1179 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1180 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1181 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1182 {CC "addressSize0", CC "()I", FN_PTR(Unsafe_AddressSize0)},
1183 {CC "pageSize", CC "()I", FN_PTR(Unsafe_PageSize)},
1184
1185 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1186 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1187 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1188 {CC "compareAndSwapObject", CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSwapObject)},
1189 {CC "compareAndSwapInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSwapInt)},
1190 {CC "compareAndSwapLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSwapLong)},
1191 {CC "compareAndExchangeObjectVolatile", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeObject)},
1192 {CC "compareAndExchangeIntVolatile", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)},
1193 {CC "compareAndExchangeLongVolatile", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)},
1194
1195 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1196 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1197
1198 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1199
1200 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1201 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1202 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1203
1204 {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)},
1205
1206 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1207
1208 {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)},
1209 {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)},
1210 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1211
1212 {CC "isBigEndian0", CC "()Z", FN_PTR(Unsafe_isBigEndian0)},
1213 {CC "unalignedAccess0", CC "()Z", FN_PTR(Unsafe_unalignedAccess0)}
1214 };
1215
1216 #undef CC
1217 #undef FN_PTR
1218
1219 #undef ADR
1220 #undef LANG
1221 #undef OBJ
1222 #undef CLS
1223 #undef FLD
1224 #undef THR
1225 #undef DC_Args
1226 #undef DAC_Args
1227
1228 #undef DECLARE_GETPUTOOP
1229 #undef DECLARE_GETPUTNATIVE
1230
1231
1232 // This function is exported, used by NativeLookup.
1233 // The Unsafe_xxx functions above are called only from the interpreter.
1234 // The optimizer looks at names and signatures to recognize
1235 // individual functions.
1236
1237 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1238 ThreadToNativeFromVM ttnfv(thread);
1239
1240 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1241 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1242 } JVM_END