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/g1/g1SATBCardTableModRefBS.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 G1SATBCardTableModRefBS::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 // The non-intrinsified versions of setOrdered just use setVolatile
382
383 UNSAFE_ENTRY(void, Unsafe_SetOrderedInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint x)) {
384 SET_FIELD_VOLATILE(obj, offset, jint, x);
385 } UNSAFE_END
386
387 UNSAFE_ENTRY(void, Unsafe_SetOrderedObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) {
388 oop x = JNIHandles::resolve(x_h);
389 oop p = JNIHandles::resolve(obj);
390 void* addr = index_oop_from_field_offset_long(p, offset);
391 OrderAccess::release();
392
393 if (UseCompressedOops) {
394 oop_store((narrowOop*)addr, x);
395 } else {
396 oop_store((oop*)addr, x);
397 }
398
399 OrderAccess::fence();
400 } UNSAFE_END
401
402 UNSAFE_ENTRY(void, Unsafe_SetOrderedLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong x)) {
403 #ifdef SUPPORTS_NATIVE_CX8
404 SET_FIELD_VOLATILE(obj, offset, jlong, x);
405 #else
406
407 // Keep old code for platforms which may not have atomic long (8 bytes) instructions
408 if (VM_Version::supports_cx8()) {
409 SET_FIELD_VOLATILE(obj, offset, jlong, x);
410 } else {
411 Handle p(THREAD, JNIHandles::resolve(obj));
412 jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
413 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
414 Atomic::store(x, addr);
415 }
416 #endif
417 } UNSAFE_END
418
419 UNSAFE_LEAF(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe)) {
420 OrderAccess::acquire();
421 } UNSAFE_END
422
423 UNSAFE_LEAF(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe)) {
424 OrderAccess::release();
425 } UNSAFE_END
426
427 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) {
428 OrderAccess::fence();
429 } UNSAFE_END
430
431 ////// Data in the C heap.
432
433 // Note: These do not throw NullPointerException for bad pointers.
434 // They just crash. Only a oop base pointer can generate a NullPointerException.
435 //
436 #define DEFINE_GETSETNATIVE(java_type, Type, native_type) \
437 \
438 UNSAFE_ENTRY(java_type, Unsafe_GetNative##Type(JNIEnv *env, jobject unsafe, jlong addr)) { \
439 void* p = addr_from_java(addr); \
440 JavaThread* t = JavaThread::current(); \
441 t->set_doing_unsafe_access(true); \
442 java_type x = *(volatile native_type*)p; \
443 t->set_doing_unsafe_access(false); \
444 return x; \
445 } UNSAFE_END \
446 \
447 UNSAFE_ENTRY(void, Unsafe_SetNative##Type(JNIEnv *env, jobject unsafe, jlong addr, java_type x)) { \
448 JavaThread* t = JavaThread::current(); \
449 t->set_doing_unsafe_access(true); \
450 void* p = addr_from_java(addr); \
451 *(volatile native_type*)p = x; \
452 t->set_doing_unsafe_access(false); \
453 } UNSAFE_END \
454 \
455 // END DEFINE_GETSETNATIVE.
456
457 DEFINE_GETSETNATIVE(jbyte, Byte, signed char)
458 DEFINE_GETSETNATIVE(jshort, Short, signed short);
459 DEFINE_GETSETNATIVE(jchar, Char, unsigned short);
460 DEFINE_GETSETNATIVE(jint, Int, jint);
461 // no long -- handled specially
462 DEFINE_GETSETNATIVE(jfloat, Float, float);
463 DEFINE_GETSETNATIVE(jdouble, Double, double);
464
465 #undef DEFINE_GETSETNATIVE
466
467 UNSAFE_ENTRY(jlong, Unsafe_GetNativeLong(JNIEnv *env, jobject unsafe, jlong addr)) {
468 JavaThread* t = JavaThread::current();
469 // We do it this way to avoid problems with access to heap using 64
470 // bit loads, as jlong in heap could be not 64-bit aligned, and on
471 // some CPUs (SPARC) it leads to SIGBUS.
472 t->set_doing_unsafe_access(true);
473 void* p = addr_from_java(addr);
474 jlong x;
475
476 if (is_ptr_aligned(p, sizeof(jlong)) == 0) {
477 // jlong is aligned, do a volatile access
478 x = *(volatile jlong*)p;
479 } else {
480 jlong_accessor acc;
481 acc.words[0] = ((volatile jint*)p)[0];
482 acc.words[1] = ((volatile jint*)p)[1];
483 x = acc.long_value;
484 }
485
486 t->set_doing_unsafe_access(false);
487
488 return x;
489 } UNSAFE_END
490
491 UNSAFE_ENTRY(void, Unsafe_SetNativeLong(JNIEnv *env, jobject unsafe, jlong addr, jlong x)) {
492 JavaThread* t = JavaThread::current();
493 // see comment for Unsafe_GetNativeLong
494 t->set_doing_unsafe_access(true);
495 void* p = addr_from_java(addr);
496
497 if (is_ptr_aligned(p, sizeof(jlong))) {
498 // jlong is aligned, do a volatile access
499 *(volatile jlong*)p = x;
500 } else {
501 jlong_accessor acc;
502 acc.long_value = x;
503 ((volatile jint*)p)[0] = acc.words[0];
504 ((volatile jint*)p)[1] = acc.words[1];
505 }
506
507 t->set_doing_unsafe_access(false);
508 } UNSAFE_END
509
510
511 UNSAFE_LEAF(jlong, Unsafe_GetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr)) {
512 void* p = addr_from_java(addr);
513
514 return addr_to_java(*(void**)p);
515 } UNSAFE_END
516
517 UNSAFE_LEAF(void, Unsafe_SetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr, jlong x)) {
518 void* p = addr_from_java(addr);
519 *(void**)p = addr_from_java(x);
520 } UNSAFE_END
521
522
523 ////// Allocation requests
524
525 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) {
526 ThreadToNativeFromVM ttnfv(thread);
527 return env->AllocObject(cls);
528 } UNSAFE_END
529
530 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) {
531 size_t sz = (size_t)size;
532
533 sz = round_to(sz, HeapWordSize);
534 void* x = os::malloc(sz, mtInternal);
535
536 return addr_to_java(x);
537 } UNSAFE_END
538
539 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) {
540 void* p = addr_from_java(addr);
541 size_t sz = (size_t)size;
542 sz = round_to(sz, HeapWordSize);
543
544 void* x = os::realloc(p, sz, mtInternal);
545
546 return addr_to_java(x);
547 } UNSAFE_END
548
549 UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) {
550 void* p = addr_from_java(addr);
551
552 os::free(p);
553 } UNSAFE_END
554
555 UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) {
556 size_t sz = (size_t)size;
557
558 oop base = JNIHandles::resolve(obj);
559 void* p = index_oop_from_field_offset_long(base, offset);
560
561 Copy::fill_to_memory_atomic(p, sz, value);
562 } UNSAFE_END
563
564 UNSAFE_ENTRY(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) {
565 size_t sz = (size_t)size;
566
567 oop srcp = JNIHandles::resolve(srcObj);
568 oop dstp = JNIHandles::resolve(dstObj);
569
570 void* src = index_oop_from_field_offset_long(srcp, srcOffset);
571 void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
572
573 Copy::conjoint_memory_atomic(src, dst, sz);
574 } UNSAFE_END
575
576 // This function is a leaf since if the source and destination are both in native memory
577 // the copy may potentially be very large, and we don't want to disable GC if we can avoid it.
578 // If either source or destination (or both) are on the heap, the function will enter VM using
579 // JVM_ENTRY_FROM_LEAF
580 UNSAFE_LEAF(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) {
581 size_t sz = (size_t)size;
582 size_t esz = (size_t)elemSize;
583
584 if (srcObj == NULL && dstObj == NULL) {
585 // Both src & dst are in native memory
586 address src = (address)srcOffset;
587 address dst = (address)dstOffset;
588
589 Copy::conjoint_swap(src, dst, sz, esz);
590 } else {
591 // At least one of src/dst are on heap, transition to VM to access raw pointers
592
593 JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) {
594 oop srcp = JNIHandles::resolve(srcObj);
595 oop dstp = JNIHandles::resolve(dstObj);
596
597 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset);
598 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset);
599
600 Copy::conjoint_swap(src, dst, sz, esz);
601 } JVM_END
602 }
603 } UNSAFE_END
604
605 ////// Random queries
606
607 UNSAFE_LEAF(jint, Unsafe_AddressSize0(JNIEnv *env, jobject unsafe)) {
608 return sizeof(void*);
609 } UNSAFE_END
610
611 UNSAFE_LEAF(jint, Unsafe_PageSize()) {
612 return os::vm_page_size();
613 } UNSAFE_END
614
615 static jint find_field_offset(jobject field, int must_be_static, TRAPS) {
616 assert(field != NULL, "field must not be NULL");
617
618 oop reflected = JNIHandles::resolve_non_null(field);
619 oop mirror = java_lang_reflect_Field::clazz(reflected);
620 Klass* k = java_lang_Class::as_Klass(mirror);
621 int slot = java_lang_reflect_Field::slot(reflected);
622 int modifiers = java_lang_reflect_Field::modifiers(reflected);
623
624 if (must_be_static >= 0) {
625 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
626 if (must_be_static != really_is_static) {
627 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
628 }
629 }
630
631 int offset = InstanceKlass::cast(k)->field_offset(slot);
632 return field_offset_from_byte_offset(offset);
633 }
634
635 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
636 return find_field_offset(field, 0, THREAD);
637 } UNSAFE_END
638
639 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) {
640 return find_field_offset(field, 1, THREAD);
641 } UNSAFE_END
642
643 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) {
644 assert(field != NULL, "field must not be NULL");
645
646 // Note: In this VM implementation, a field address is always a short
647 // offset from the base of a a klass metaobject. Thus, the full dynamic
648 // range of the return type is never used. However, some implementations
649 // might put the static field inside an array shared by many classes,
650 // or even at a fixed address, in which case the address could be quite
651 // large. In that last case, this function would return NULL, since
652 // the address would operate alone, without any base pointer.
653
654 oop reflected = JNIHandles::resolve_non_null(field);
655 oop mirror = java_lang_reflect_Field::clazz(reflected);
656 int modifiers = java_lang_reflect_Field::modifiers(reflected);
657
658 if ((modifiers & JVM_ACC_STATIC) == 0) {
659 THROW_0(vmSymbols::java_lang_IllegalArgumentException());
660 }
661
662 return JNIHandles::make_local(env, mirror);
663 } UNSAFE_END
664
665 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
666 assert(clazz != NULL, "clazz must not be NULL");
667
668 oop mirror = JNIHandles::resolve_non_null(clazz);
669
670 Klass* klass = java_lang_Class::as_Klass(mirror);
671 if (klass != NULL && klass->should_be_initialized()) {
672 InstanceKlass* k = InstanceKlass::cast(klass);
673 k->initialize(CHECK);
674 }
675 }
676 UNSAFE_END
677
678 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) {
679 assert(clazz != NULL, "clazz must not be NULL");
680
681 oop mirror = JNIHandles::resolve_non_null(clazz);
682 Klass* klass = java_lang_Class::as_Klass(mirror);
683
684 if (klass != NULL && klass->should_be_initialized()) {
685 return true;
686 }
687
688 return false;
689 }
690 UNSAFE_END
691
692 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) {
693 assert(clazz != NULL, "clazz must not be NULL");
694
695 oop mirror = JNIHandles::resolve_non_null(clazz);
696 Klass* k = java_lang_Class::as_Klass(mirror);
697
698 if (k == NULL || !k->is_array_klass()) {
699 THROW(vmSymbols::java_lang_InvalidClassException());
700 } else if (k->is_objArray_klass()) {
701 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
702 scale = heapOopSize;
703 } else if (k->is_typeArray_klass()) {
704 TypeArrayKlass* tak = TypeArrayKlass::cast(k);
705 base = tak->array_header_in_bytes();
706 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
707 scale = (1 << tak->log2_element_size());
708 } else {
709 ShouldNotReachHere();
710 }
711 }
712
713 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) {
714 int base = 0, scale = 0;
715 getBaseAndScale(base, scale, clazz, CHECK_0);
716
717 return field_offset_from_byte_offset(base);
718 } UNSAFE_END
719
720
721 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) {
722 int base = 0, scale = 0;
723 getBaseAndScale(base, scale, clazz, CHECK_0);
724
725 // This VM packs both fields and array elements down to the byte.
726 // But watch out: If this changes, so that array references for
727 // a given primitive type (say, T_BOOLEAN) use different memory units
728 // than fields, this method MUST return zero for such arrays.
729 // For example, the VM used to store sub-word sized fields in full
730 // words in the object layout, so that accessors like getByte(Object,int)
731 // did not really do what one might expect for arrays. Therefore,
732 // this function used to report a zero scale factor, so that the user
733 // would know not to attempt to access sub-word array elements.
734 // // Code for unpacked fields:
735 // if (scale < wordSize) return 0;
736
737 // The following allows for a pretty general fieldOffset cookie scheme,
738 // but requires it to be linear in byte offset.
739 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
740 } UNSAFE_END
741
742
743 static inline void throw_new(JNIEnv *env, const char *ename) {
744 char buf[100];
745
746 jio_snprintf(buf, 100, "%s%s", "java/lang/", ename);
747
748 jclass cls = env->FindClass(buf);
749 if (env->ExceptionCheck()) {
750 env->ExceptionClear();
751 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", buf);
752 return;
753 }
754
755 env->ThrowNew(cls, NULL);
756 }
757
758 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
759 // Code lifted from JDK 1.3 ClassLoader.c
760
761 jbyte *body;
762 char *utfName = NULL;
763 jclass result = 0;
764 char buf[128];
765
766 assert(data != NULL, "Class bytes must not be NULL");
767 assert(length >= 0, "length must not be negative: %d", length);
768
769 if (UsePerfData) {
770 ClassLoader::unsafe_defineClassCallCounter()->inc();
771 }
772
773 body = NEW_C_HEAP_ARRAY(jbyte, length, mtInternal);
774 if (body == NULL) {
775 throw_new(env, "OutOfMemoryError");
776 return 0;
777 }
778
779 env->GetByteArrayRegion(data, offset, length, body);
780 if (env->ExceptionOccurred()) {
781 goto free_body;
782 }
783
784 if (name != NULL) {
785 uint len = env->GetStringUTFLength(name);
786 int unicode_len = env->GetStringLength(name);
787
788 if (len >= sizeof(buf)) {
789 utfName = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
790 if (utfName == NULL) {
791 throw_new(env, "OutOfMemoryError");
792 goto free_body;
793 }
794 } else {
795 utfName = buf;
796 }
797
798 env->GetStringUTFRegion(name, 0, unicode_len, utfName);
799
800 for (uint i = 0; i < len; i++) {
801 if (utfName[i] == '.') utfName[i] = '/';
802 }
803 }
804
805 result = JVM_DefineClass(env, utfName, loader, body, length, pd);
806
807 if (utfName && utfName != buf) {
808 FREE_C_HEAP_ARRAY(char, utfName);
809 }
810
811 free_body:
812 FREE_C_HEAP_ARRAY(jbyte, body);
813 return result;
814 }
815
816
817 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) {
818 ThreadToNativeFromVM ttnfv(thread);
819
820 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
821 } UNSAFE_END
822
823
824 // define a class but do not make it known to the class loader or system dictionary
825 // - host_class: supplies context for linkage, access control, protection domain, and class loader
826 // - data: bytes of a class file, a raw memory address (length gives the number of bytes)
827 // - cp_patches: where non-null entries exist, they replace corresponding CP entries in data
828
829 // When you load an anonymous class U, it works as if you changed its name just before loading,
830 // to a name that you will never use again. Since the name is lost, no other class can directly
831 // link to any member of U. Just after U is loaded, the only way to use it is reflectively,
832 // through java.lang.Class methods like Class.newInstance.
833
834 // Access checks for linkage sites within U continue to follow the same rules as for named classes.
835 // The package of an anonymous class is given by the package qualifier on the name under which it was loaded.
836 // An anonymous class also has special privileges to access any member of its host class.
837 // This is the main reason why this loading operation is unsafe. The purpose of this is to
838 // allow language implementations to simulate "open classes"; a host class in effect gets
839 // new code when an anonymous class is loaded alongside it. A less convenient but more
840 // standard way to do this is with reflection, which can also be set to ignore access
841 // restrictions.
842
843 // Access into an anonymous class is possible only through reflection. Therefore, there
844 // are no special access rules for calling into an anonymous class. The relaxed access
845 // rule for the host class is applied in the opposite direction: A host class reflectively
846 // access one of its anonymous classes.
847
848 // If you load the same bytecodes twice, you get two different classes. You can reload
849 // the same bytecodes with or without varying CP patches.
850
851 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
852 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
853 // The CONSTANT_Class entry for that name can be patched to refer directly to U1.
854
855 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as
856 // an outer class (so that U2 is an anonymous inner class of anonymous U1).
857 // It is not possible for a named class, or an older anonymous class, to refer by
858 // name (via its CP) to a newer anonymous class.
859
860 // CP patching may also be used to modify (i.e., hack) the names of methods, classes,
861 // or type descriptors used in the loaded anonymous class.
862
863 // Finally, CP patching may be used to introduce "live" objects into the constant pool,
864 // instead of "dead" strings. A compiled statement like println((Object)"hello") can
865 // be changed to println(greeting), where greeting is an arbitrary object created before
866 // the anonymous class is loaded. This is useful in dynamic languages, in which
867 // various kinds of metaobjects must be introduced as constants into bytecode.
868 // Note the cast (Object), which tells the verifier to expect an arbitrary object,
869 // not just a literal string. For such ldc instructions, the verifier uses the
870 // type Object instead of String, if the loaded constant is not in fact a String.
871
872 static instanceKlassHandle
873 Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
874 jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
875 u1** temp_alloc,
876 TRAPS) {
877 assert(host_class != NULL, "host_class must not be NULL");
878 assert(data != NULL, "data must not be NULL");
879
880 if (UsePerfData) {
881 ClassLoader::unsafe_defineClassCallCounter()->inc();
882 }
883
884 jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
885 assert(length >= 0, "class_bytes_length must not be negative: %d", length);
886
887 int class_bytes_length = (int) length;
888
889 u1* class_bytes = NEW_C_HEAP_ARRAY(u1, length, mtInternal);
890 if (class_bytes == NULL) {
891 THROW_0(vmSymbols::java_lang_OutOfMemoryError());
892 }
893
894 // caller responsible to free it:
895 *temp_alloc = class_bytes;
896
897 jbyte* array_base = typeArrayOop(JNIHandles::resolve_non_null(data))->byte_at_addr(0);
898 Copy::conjoint_jbytes(array_base, class_bytes, length);
899
900 objArrayHandle cp_patches_h;
901 if (cp_patches_jh != NULL) {
902 oop p = JNIHandles::resolve_non_null(cp_patches_jh);
903 assert(p->is_objArray(), "cp_patches must be an object[]");
904 cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
905 }
906
907 const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class));
908 assert(host_klass != NULL, "invariant");
909
910 const char* host_source = host_klass->external_name();
911 Handle host_loader(THREAD, host_klass->class_loader());
912 Handle host_domain(THREAD, host_klass->protection_domain());
913
914 GrowableArray<Handle>* cp_patches = NULL;
915
916 if (cp_patches_h.not_null()) {
917 int alen = cp_patches_h->length();
918
919 for (int i = alen-1; i >= 0; i--) {
920 oop p = cp_patches_h->obj_at(i);
921 if (p != NULL) {
922 Handle patch(THREAD, p);
923
924 if (cp_patches == NULL) {
925 cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
926 }
927
928 cp_patches->at_put(i, patch);
929 }
930 }
931 }
932
933 ClassFileStream st(class_bytes, class_bytes_length, host_source, ClassFileStream::verify);
934
935 Symbol* no_class_name = NULL;
936 Klass* anonk = SystemDictionary::parse_stream(no_class_name,
937 host_loader,
938 host_domain,
939 &st,
940 host_klass,
941 cp_patches,
942 CHECK_NULL);
943 if (anonk == NULL) {
944 return NULL;
945 }
946
947 return instanceKlassHandle(THREAD, anonk);
948 }
949
950 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) {
951 ResourceMark rm(THREAD);
952
953 instanceKlassHandle anon_klass;
954 jobject res_jh = NULL;
955 u1* temp_alloc = NULL;
956
957 anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data, cp_patches_jh, &temp_alloc, THREAD);
958 if (anon_klass() != NULL) {
959 res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
960 }
961
962 // try/finally clause:
963 if (temp_alloc != NULL) {
964 FREE_C_HEAP_ARRAY(u1, temp_alloc);
965 }
966
967 // The anonymous class loader data has been artificially been kept alive to
968 // this point. The mirror and any instances of this class have to keep
969 // it alive afterwards.
970 if (anon_klass() != NULL) {
971 anon_klass->class_loader_data()->set_keep_alive(false);
972 }
973
974 // let caller initialize it as needed...
975
976 return (jclass) res_jh;
977 } UNSAFE_END
978
979 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) {
980 ThreadToNativeFromVM ttnfv(thread);
981 env->Throw(thr);
982 } UNSAFE_END
983
984 // JSR166 ------------------------------------------------------------------
985
986 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) {
987 oop x = JNIHandles::resolve(x_h);
988 oop e = JNIHandles::resolve(e_h);
989 oop p = JNIHandles::resolve(obj);
990 HeapWord* addr = (HeapWord *)index_oop_from_field_offset_long(p, offset);
991 oop res = oopDesc::atomic_compare_exchange_oop(x, addr, e, true);
992 if (res != e) {
993 return false;
994 }
995
996 update_barrier_set((void*)addr, x);
997
998 return true;
999 } UNSAFE_END
1000
1001 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) {
1002 oop p = JNIHandles::resolve(obj);
1003 jint* addr = (jint *) index_oop_from_field_offset_long(p, offset);
1004
1005 return (jint)(Atomic::cmpxchg(x, addr, e)) == e;
1006 } UNSAFE_END
1007
1008 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) {
1009 Handle p(THREAD, JNIHandles::resolve(obj));
1010 jlong* addr = (jlong*)index_oop_from_field_offset_long(p(), offset);
1011
1012 #ifdef SUPPORTS_NATIVE_CX8
1013 return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
1014 #else
1015 if (VM_Version::supports_cx8()) {
1016 return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
1017 } else {
1018 MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
1019
1020 jlong val = Atomic::load(addr);
1021 if (val != e) {
1022 return false;
1023 }
1024
1025 Atomic::store(x, addr);
1026 return true;
1027 }
1028 #endif
1029 } UNSAFE_END
1030
1031 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) {
1032 EventThreadPark event;
1033 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time);
1034
1035 JavaThreadParkedState jtps(thread, time != 0);
1036 thread->parker()->park(isAbsolute != 0, time);
1037
1038 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker());
1039
1040 if (event.should_commit()) {
1041 oop obj = thread->current_park_blocker();
1042 event.set_klass((obj != NULL) ? obj->klass() : NULL);
1043 event.set_timeout(time);
1044 event.set_address((obj != NULL) ? (TYPE_ADDRESS) cast_from_oop<uintptr_t>(obj) : 0);
1045 event.commit();
1046 }
1047 } UNSAFE_END
1048
1049 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) {
1050 Parker* p = NULL;
1051
1052 if (jthread != NULL) {
1053 oop java_thread = JNIHandles::resolve_non_null(jthread);
1054 if (java_thread != NULL) {
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 // Grab lock if apparently null or using older version of library
1063 MutexLocker mu(Threads_lock);
1064 java_thread = JNIHandles::resolve_non_null(jthread);
1065
1066 if (java_thread != NULL) {
1067 JavaThread* thr = java_lang_Thread::thread(java_thread);
1068 if (thr != NULL) {
1069 p = thr->parker();
1070 if (p != NULL) { // Bind to Java thread for next time.
1071 java_lang_Thread::set_park_event(java_thread, addr_to_java(p));
1072 }
1073 }
1074 }
1075 }
1076 }
1077 }
1078
1079 if (p != NULL) {
1080 HOTSPOT_THREAD_UNPARK((uintptr_t) p);
1081 p->unpark();
1082 }
1083 } UNSAFE_END
1084
1085 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) {
1086 const int max_nelem = 3;
1087 double la[max_nelem];
1088 jint ret;
1089
1090 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
1091 assert(a->is_typeArray(), "must be type array");
1092
1093 ret = os::loadavg(la, nelem);
1094 if (ret == -1) {
1095 return -1;
1096 }
1097
1098 // if successful, ret is the number of samples actually retrieved.
1099 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
1100 switch(ret) {
1101 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
1102 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
1103 case 1: a->double_at_put(0, (jdouble)la[0]); break;
1104 }
1105
1106 return ret;
1107 } UNSAFE_END
1108
1109
1110 /// JVM_RegisterUnsafeMethods
1111
1112 #define ADR "J"
1113
1114 #define LANG "Ljava/lang/"
1115
1116 #define OBJ LANG "Object;"
1117 #define CLS LANG "Class;"
1118 #define FLD LANG "reflect/Field;"
1119 #define THR LANG "Throwable;"
1120
1121 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
1122 #define DAC_Args CLS "[B[" OBJ
1123
1124 #define CC (char*) /*cast a literal from (const char*)*/
1125 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1126
1127 #define DECLARE_GETPUTOOP(Type, Desc) \
1128 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \
1129 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Set##Type)}, \
1130 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \
1131 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Set##Type##Volatile)}
1132
1133
1134 #define DECLARE_GETPUTNATIVE(Byte, B) \
1135 {CC "get" #Byte, CC "(" ADR ")" #B, FN_PTR(Unsafe_GetNative##Byte)}, \
1136 {CC "put" #Byte, CC "(" ADR#B ")V", FN_PTR(Unsafe_SetNative##Byte)}
1137
1138 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = {
1139 {CC "getObject", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObject)},
1140 {CC "putObject", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_SetObject)},
1141 {CC "getObjectVolatile",CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObjectVolatile)},
1142 {CC "putObjectVolatile",CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_SetObjectVolatile)},
1143
1144 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)},
1145 {CC "getJavaMirror", CC "(" ADR ")" CLS, FN_PTR(Unsafe_GetJavaMirror)},
1146 {CC "getKlassPointer", CC "(" OBJ ")" ADR, FN_PTR(Unsafe_GetKlassPointer)},
1147
1148 DECLARE_GETPUTOOP(Boolean, Z),
1149 DECLARE_GETPUTOOP(Byte, B),
1150 DECLARE_GETPUTOOP(Short, S),
1151 DECLARE_GETPUTOOP(Char, C),
1152 DECLARE_GETPUTOOP(Int, I),
1153 DECLARE_GETPUTOOP(Long, J),
1154 DECLARE_GETPUTOOP(Float, F),
1155 DECLARE_GETPUTOOP(Double, D),
1156
1157 DECLARE_GETPUTNATIVE(Byte, B),
1158 DECLARE_GETPUTNATIVE(Short, S),
1159 DECLARE_GETPUTNATIVE(Char, C),
1160 DECLARE_GETPUTNATIVE(Int, I),
1161 DECLARE_GETPUTNATIVE(Long, J),
1162 DECLARE_GETPUTNATIVE(Float, F),
1163 DECLARE_GETPUTNATIVE(Double, D),
1164
1165 {CC "getAddress", CC "(" ADR ")" ADR, FN_PTR(Unsafe_GetNativeAddress)},
1166 {CC "putAddress", CC "(" ADR "" ADR ")V", FN_PTR(Unsafe_SetNativeAddress)},
1167
1168 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)},
1169 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)},
1170 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)},
1171
1172 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)},
1173 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)},
1174 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)},
1175 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)},
1176 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)},
1177 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)},
1178 {CC "addressSize0", CC "()I", FN_PTR(Unsafe_AddressSize0)},
1179 {CC "pageSize", CC "()I", FN_PTR(Unsafe_PageSize)},
1180
1181 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)},
1182 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)},
1183 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)},
1184 {CC "compareAndSwapObject", CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSwapObject)},
1185 {CC "compareAndSwapInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSwapInt)},
1186 {CC "compareAndSwapLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSwapLong)},
1187 {CC "putOrderedObject", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_SetOrderedObject)},
1188 {CC "putOrderedInt", CC "(" OBJ "JI)V", FN_PTR(Unsafe_SetOrderedInt)},
1189 {CC "putOrderedLong", CC "(" OBJ "JJ)V", FN_PTR(Unsafe_SetOrderedLong)},
1190 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)},
1191 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)},
1192
1193 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)},
1194
1195 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)},
1196 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)},
1197 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)},
1198
1199 {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)},
1200
1201 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)},
1202
1203 {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)},
1204 {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)},
1205 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)},
1206
1207 {CC "isBigEndian0", CC "()Z", FN_PTR(Unsafe_isBigEndian0)},
1208 {CC "unalignedAccess0", CC "()Z", FN_PTR(Unsafe_unalignedAccess0)}
1209 };
1210
1211 #undef CC
1212 #undef FN_PTR
1213
1214 #undef ADR
1215 #undef LANG
1216 #undef OBJ
1217 #undef CLS
1218 #undef FLD
1219 #undef THR
1220 #undef DC_Args
1221 #undef DAC_Args
1222
1223 #undef DECLARE_GETPUTOOP
1224 #undef DECLARE_GETPUTNATIVE
1225
1226
1227 // This function is exported, used by NativeLookup.
1228 // The Unsafe_xxx functions above are called only from the interpreter.
1229 // The optimizer looks at names and signatures to recognize
1230 // individual functions.
1231
1232 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) {
1233 ThreadToNativeFromVM ttnfv(thread);
1234
1235 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod));
1236 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives");
1237 } JVM_END