1 /* 2 * Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "jni.h" 27 #include "jvm.h" 28 #include "classfile/classFileStream.hpp" 29 #include "classfile/classLoader.hpp" 30 #include "classfile/vmSymbols.hpp" 31 #include "jfr/jfrEvents.hpp" 32 #include "memory/allocation.inline.hpp" 33 #include "memory/resourceArea.hpp" 34 #include "oops/access.inline.hpp" 35 #include "oops/fieldStreams.inline.hpp" 36 #include "oops/objArrayOop.inline.hpp" 37 #include "oops/oop.inline.hpp" 38 #include "oops/typeArrayOop.inline.hpp" 39 #include "prims/unsafe.hpp" 40 #include "runtime/atomic.hpp" 41 #include "runtime/globals.hpp" 42 #include "runtime/handles.inline.hpp" 43 #include "runtime/interfaceSupport.inline.hpp" 44 #include "runtime/jniHandles.inline.hpp" 45 #include "runtime/orderAccess.hpp" 46 #include "runtime/reflection.hpp" 47 #include "runtime/sharedRuntime.hpp" 48 #include "runtime/thread.hpp" 49 #include "runtime/threadSMR.hpp" 50 #include "runtime/vm_version.hpp" 51 #include "services/threadService.hpp" 52 #include "utilities/align.hpp" 53 #include "utilities/copy.hpp" 54 #include "utilities/dtrace.hpp" 55 #include "utilities/macros.hpp" 56 57 /** 58 * Implementation of the jdk.internal.misc.Unsafe class 59 */ 60 61 62 #define MAX_OBJECT_SIZE \ 63 ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \ 64 + ((julong)max_jint * sizeof(double)) ) 65 66 67 #define UNSAFE_ENTRY(result_type, header) \ 68 JVM_ENTRY(static result_type, header) 69 70 #define UNSAFE_LEAF(result_type, header) \ 71 JVM_LEAF(static result_type, header) 72 73 #define UNSAFE_END JVM_END 74 75 76 static inline void* addr_from_java(jlong addr) { 77 // This assert fails in a variety of ways on 32-bit systems. 78 // It is impossible to predict whether native code that converts 79 // pointers to longs will sign-extend or zero-extend the addresses. 80 //assert(addr == (uintptr_t)addr, "must not be odd high bits"); 81 return (void*)(uintptr_t)addr; 82 } 83 84 static inline jlong addr_to_java(void* p) { 85 assert(p == (void*)(uintptr_t)p, "must not be odd high bits"); 86 return (uintptr_t)p; 87 } 88 89 90 // Note: The VM's obj_field and related accessors use byte-scaled 91 // ("unscaled") offsets, just as the unsafe methods do. 92 93 // However, the method Unsafe.fieldOffset explicitly declines to 94 // guarantee this. The field offset values manipulated by the Java user 95 // through the Unsafe API are opaque cookies that just happen to be byte 96 // offsets. We represent this state of affairs by passing the cookies 97 // through conversion functions when going between the VM and the Unsafe API. 98 // The conversion functions just happen to be no-ops at present. 99 100 static inline jlong field_offset_to_byte_offset(jlong field_offset) { 101 return field_offset; 102 } 103 104 static inline jlong field_offset_from_byte_offset(jlong byte_offset) { 105 return byte_offset; 106 } 107 108 static inline void assert_field_offset_sane(oop p, jlong field_offset) { 109 #ifdef ASSERT 110 jlong byte_offset = field_offset_to_byte_offset(field_offset); 111 112 if (p != NULL) { 113 assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset"); 114 if (byte_offset == (jint)byte_offset) { 115 void* ptr_plus_disp = (address)p + byte_offset; 116 assert(p->field_addr_raw((jint)byte_offset) == ptr_plus_disp, 117 "raw [ptr+disp] must be consistent with oop::field_addr_raw"); 118 } 119 jlong p_size = HeapWordSize * (jlong)(p->size()); 120 assert(byte_offset < p_size, "Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, (int64_t)byte_offset, (int64_t)p_size); 121 } 122 #endif 123 } 124 125 static inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) { 126 assert_field_offset_sane(p, field_offset); 127 jlong byte_offset = field_offset_to_byte_offset(field_offset); 128 129 if (p != NULL) { 130 p = Access<>::resolve(p); 131 } 132 133 if (sizeof(char*) == sizeof(jint)) { // (this constant folds!) 134 return (address)p + (jint) byte_offset; 135 } else { 136 return (address)p + byte_offset; 137 } 138 } 139 140 // Externally callable versions: 141 // (Use these in compiler intrinsics which emulate unsafe primitives.) 142 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) { 143 return field_offset; 144 } 145 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) { 146 return byte_offset; 147 } 148 149 150 ///// Data read/writes on the Java heap and in native (off-heap) memory 151 152 /** 153 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access() 154 */ 155 class GuardUnsafeAccess { 156 JavaThread* _thread; 157 158 public: 159 GuardUnsafeAccess(JavaThread* thread) : _thread(thread) { 160 // native/off-heap access which may raise SIGBUS if accessing 161 // memory mapped file data in a region of the file which has 162 // been truncated and is now invalid. 163 _thread->set_doing_unsafe_access(true); 164 } 165 166 ~GuardUnsafeAccess() { 167 _thread->set_doing_unsafe_access(false); 168 } 169 }; 170 171 /** 172 * Helper class for accessing memory. 173 * 174 * Normalizes values and wraps accesses in 175 * JavaThread::doing_unsafe_access() if needed. 176 */ 177 template <typename T> 178 class MemoryAccess : StackObj { 179 JavaThread* _thread; 180 oop _obj; 181 ptrdiff_t _offset; 182 183 // Resolves and returns the address of the memory access. 184 // This raw memory access may fault, so we make sure it happens within the 185 // guarded scope by making the access volatile at least. Since the store 186 // of Thread::set_doing_unsafe_access() is also volatile, these accesses 187 // can not be reordered by the compiler. Therefore, if the access triggers 188 // a fault, we will know that Thread::doing_unsafe_access() returns true. 189 volatile T* addr() { 190 void* addr = index_oop_from_field_offset_long(_obj, _offset); 191 return static_cast<volatile T*>(addr); 192 } 193 194 template <typename U> 195 U normalize_for_write(U x) { 196 return x; 197 } 198 199 jboolean normalize_for_write(jboolean x) { 200 return x & 1; 201 } 202 203 template <typename U> 204 U normalize_for_read(U x) { 205 return x; 206 } 207 208 jboolean normalize_for_read(jboolean x) { 209 return x != 0; 210 } 211 212 public: 213 MemoryAccess(JavaThread* thread, jobject obj, jlong offset) 214 : _thread(thread), _obj(JNIHandles::resolve(obj)), _offset((ptrdiff_t)offset) { 215 assert_field_offset_sane(_obj, offset); 216 } 217 218 T get() { 219 if (_obj == NULL) { 220 GuardUnsafeAccess guard(_thread); 221 T ret = RawAccess<>::load(addr()); 222 return normalize_for_read(ret); 223 } else { 224 T ret = HeapAccess<>::load_at(_obj, _offset); 225 return normalize_for_read(ret); 226 } 227 } 228 229 void put(T x) { 230 if (_obj == NULL) { 231 GuardUnsafeAccess guard(_thread); 232 RawAccess<>::store(addr(), normalize_for_write(x)); 233 } else { 234 HeapAccess<>::store_at(_obj, _offset, normalize_for_write(x)); 235 } 236 } 237 238 239 T get_volatile() { 240 if (_obj == NULL) { 241 GuardUnsafeAccess guard(_thread); 242 volatile T ret = RawAccess<MO_SEQ_CST>::load(addr()); 243 return normalize_for_read(ret); 244 } else { 245 T ret = HeapAccess<MO_SEQ_CST>::load_at(_obj, _offset); 246 return normalize_for_read(ret); 247 } 248 } 249 250 void put_volatile(T x) { 251 if (_obj == NULL) { 252 GuardUnsafeAccess guard(_thread); 253 RawAccess<MO_SEQ_CST>::store(addr(), normalize_for_write(x)); 254 } else { 255 HeapAccess<MO_SEQ_CST>::store_at(_obj, _offset, normalize_for_write(x)); 256 } 257 } 258 }; 259 260 // These functions allow a null base pointer with an arbitrary address. 261 // But if the base pointer is non-null, the offset should make some sense. 262 // That is, it should be in the range [0, MAX_OBJECT_SIZE]. 263 UNSAFE_ENTRY(jobject, Unsafe_GetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { 264 oop p = JNIHandles::resolve(obj); 265 assert_field_offset_sane(p, offset); 266 oop v = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset); 267 return JNIHandles::make_local(env, v); 268 } UNSAFE_END 269 270 UNSAFE_ENTRY(void, Unsafe_PutReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) { 271 oop x = JNIHandles::resolve(x_h); 272 oop p = JNIHandles::resolve(obj); 273 assert_field_offset_sane(p, offset); 274 HeapAccess<ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x); 275 } UNSAFE_END 276 277 UNSAFE_ENTRY(jobject, Unsafe_GetReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { 278 oop p = JNIHandles::resolve(obj); 279 assert_field_offset_sane(p, offset); 280 oop v = HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset); 281 return JNIHandles::make_local(env, v); 282 } UNSAFE_END 283 284 UNSAFE_ENTRY(void, Unsafe_PutReferenceVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) { 285 oop x = JNIHandles::resolve(x_h); 286 oop p = JNIHandles::resolve(obj); 287 assert_field_offset_sane(p, offset); 288 HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x); 289 } UNSAFE_END 290 291 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) { 292 oop v = *(oop*) (address) addr; 293 return JNIHandles::make_local(env, v); 294 } UNSAFE_END 295 296 #define DEFINE_GETSETOOP(java_type, Type) \ 297 \ 298 UNSAFE_ENTRY(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \ 299 return MemoryAccess<java_type>(thread, obj, offset).get(); \ 300 } UNSAFE_END \ 301 \ 302 UNSAFE_ENTRY(void, Unsafe_Put##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \ 303 MemoryAccess<java_type>(thread, obj, offset).put(x); \ 304 } UNSAFE_END \ 305 \ 306 // END DEFINE_GETSETOOP. 307 308 DEFINE_GETSETOOP(jboolean, Boolean) 309 DEFINE_GETSETOOP(jbyte, Byte) 310 DEFINE_GETSETOOP(jshort, Short); 311 DEFINE_GETSETOOP(jchar, Char); 312 DEFINE_GETSETOOP(jint, Int); 313 DEFINE_GETSETOOP(jlong, Long); 314 DEFINE_GETSETOOP(jfloat, Float); 315 DEFINE_GETSETOOP(jdouble, Double); 316 317 #undef DEFINE_GETSETOOP 318 319 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \ 320 \ 321 UNSAFE_ENTRY(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \ 322 return MemoryAccess<java_type>(thread, obj, offset).get_volatile(); \ 323 } UNSAFE_END \ 324 \ 325 UNSAFE_ENTRY(void, Unsafe_Put##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \ 326 MemoryAccess<java_type>(thread, obj, offset).put_volatile(x); \ 327 } UNSAFE_END \ 328 \ 329 // END DEFINE_GETSETOOP_VOLATILE. 330 331 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean) 332 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte) 333 DEFINE_GETSETOOP_VOLATILE(jshort, Short); 334 DEFINE_GETSETOOP_VOLATILE(jchar, Char); 335 DEFINE_GETSETOOP_VOLATILE(jint, Int); 336 DEFINE_GETSETOOP_VOLATILE(jlong, Long); 337 DEFINE_GETSETOOP_VOLATILE(jfloat, Float); 338 DEFINE_GETSETOOP_VOLATILE(jdouble, Double); 339 340 #undef DEFINE_GETSETOOP_VOLATILE 341 342 UNSAFE_LEAF(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe)) { 343 OrderAccess::acquire(); 344 } UNSAFE_END 345 346 UNSAFE_LEAF(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe)) { 347 OrderAccess::release(); 348 } UNSAFE_END 349 350 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) { 351 OrderAccess::fence(); 352 } UNSAFE_END 353 354 ////// Allocation requests 355 356 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) { 357 ThreadToNativeFromVM ttnfv(thread); 358 return env->AllocObject(cls); 359 } UNSAFE_END 360 361 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) { 362 size_t sz = (size_t)size; 363 364 sz = align_up(sz, HeapWordSize); 365 void* x = os::malloc(sz, mtOther); 366 367 return addr_to_java(x); 368 } UNSAFE_END 369 370 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) { 371 void* p = addr_from_java(addr); 372 size_t sz = (size_t)size; 373 sz = align_up(sz, HeapWordSize); 374 375 void* x = os::realloc(p, sz, mtOther); 376 377 return addr_to_java(x); 378 } UNSAFE_END 379 380 UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) { 381 void* p = addr_from_java(addr); 382 383 os::free(p); 384 } UNSAFE_END 385 386 UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) { 387 size_t sz = (size_t)size; 388 389 oop base = JNIHandles::resolve(obj); 390 void* p = index_oop_from_field_offset_long(base, offset); 391 392 Copy::fill_to_memory_atomic(p, sz, value); 393 } UNSAFE_END 394 395 UNSAFE_ENTRY(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) { 396 size_t sz = (size_t)size; 397 398 oop srcp = JNIHandles::resolve(srcObj); 399 oop dstp = JNIHandles::resolve(dstObj); 400 401 void* src = index_oop_from_field_offset_long(srcp, srcOffset); 402 void* dst = index_oop_from_field_offset_long(dstp, dstOffset); 403 { 404 GuardUnsafeAccess guard(thread); 405 if (StubRoutines::unsafe_arraycopy() != NULL) { 406 StubRoutines::UnsafeArrayCopy_stub()(src, dst, sz); 407 } else { 408 Copy::conjoint_memory_atomic(src, dst, sz); 409 } 410 } 411 } UNSAFE_END 412 413 // This function is a leaf since if the source and destination are both in native memory 414 // the copy may potentially be very large, and we don't want to disable GC if we can avoid it. 415 // If either source or destination (or both) are on the heap, the function will enter VM using 416 // JVM_ENTRY_FROM_LEAF 417 UNSAFE_LEAF(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) { 418 size_t sz = (size_t)size; 419 size_t esz = (size_t)elemSize; 420 421 if (srcObj == NULL && dstObj == NULL) { 422 // Both src & dst are in native memory 423 address src = (address)srcOffset; 424 address dst = (address)dstOffset; 425 426 { 427 JavaThread* thread = JavaThread::thread_from_jni_environment(env); 428 GuardUnsafeAccess guard(thread); 429 Copy::conjoint_swap(src, dst, sz, esz); 430 } 431 } else { 432 // At least one of src/dst are on heap, transition to VM to access raw pointers 433 434 JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) { 435 oop srcp = JNIHandles::resolve(srcObj); 436 oop dstp = JNIHandles::resolve(dstObj); 437 438 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset); 439 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset); 440 441 { 442 GuardUnsafeAccess guard(thread); 443 Copy::conjoint_swap(src, dst, sz, esz); 444 } 445 } JVM_END 446 } 447 } UNSAFE_END 448 449 UNSAFE_LEAF (void, Unsafe_WriteBack0(JNIEnv *env, jobject unsafe, jlong line)) { 450 assert(VM_Version::supports_data_cache_line_flush(), "should not get here"); 451 #ifdef ASSERT 452 if (TraceMemoryWriteback) { 453 tty->print_cr("Unsafe: writeback 0x%p", addr_from_java(line)); 454 } 455 #endif 456 457 assert(StubRoutines::data_cache_writeback() != NULL, "sanity"); 458 (StubRoutines::DataCacheWriteback_stub())(addr_from_java(line)); 459 } UNSAFE_END 460 461 static void doWriteBackSync0(bool is_pre) 462 { 463 assert(StubRoutines::data_cache_writeback_sync() != NULL, "sanity"); 464 (StubRoutines::DataCacheWritebackSync_stub())(is_pre); 465 } 466 467 UNSAFE_LEAF (void, Unsafe_WriteBackPreSync0(JNIEnv *env, jobject unsafe)) { 468 assert(VM_Version::supports_data_cache_line_flush(), "should not get here"); 469 #ifdef ASSERT 470 if (TraceMemoryWriteback) { 471 tty->print_cr("Unsafe: writeback pre-sync"); 472 } 473 #endif 474 475 doWriteBackSync0(true); 476 } UNSAFE_END 477 478 UNSAFE_LEAF (void, Unsafe_WriteBackPostSync0(JNIEnv *env, jobject unsafe)) { 479 assert(VM_Version::supports_data_cache_line_flush(), "should not get here"); 480 #ifdef ASSERT 481 if (TraceMemoryWriteback) { 482 tty->print_cr("Unsafe: writeback pre-sync"); 483 } 484 #endif 485 486 doWriteBackSync0(false); 487 } UNSAFE_END 488 489 ////// Random queries 490 491 static jlong find_field_offset(jclass clazz, jstring name, TRAPS) { 492 assert(clazz != NULL, "clazz must not be NULL"); 493 assert(name != NULL, "name must not be NULL"); 494 495 ResourceMark rm(THREAD); 496 char *utf_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name)); 497 498 InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz))); 499 500 jint offset = -1; 501 for (JavaFieldStream fs(k); !fs.done(); fs.next()) { 502 Symbol *name = fs.name(); 503 if (name->equals(utf_name)) { 504 offset = fs.offset(); 505 break; 506 } 507 } 508 if (offset < 0) { 509 THROW_0(vmSymbols::java_lang_InternalError()); 510 } 511 return field_offset_from_byte_offset(offset); 512 } 513 514 static jlong find_field_offset(jobject field, int must_be_static, TRAPS) { 515 assert(field != NULL, "field must not be NULL"); 516 517 oop reflected = JNIHandles::resolve_non_null(field); 518 oop mirror = java_lang_reflect_Field::clazz(reflected); 519 Klass* k = java_lang_Class::as_Klass(mirror); 520 int slot = java_lang_reflect_Field::slot(reflected); 521 int modifiers = java_lang_reflect_Field::modifiers(reflected); 522 523 if (must_be_static >= 0) { 524 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0); 525 if (must_be_static != really_is_static) { 526 THROW_0(vmSymbols::java_lang_IllegalArgumentException()); 527 } 528 } 529 530 int offset = InstanceKlass::cast(k)->field_offset(slot); 531 return field_offset_from_byte_offset(offset); 532 } 533 534 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) { 535 return find_field_offset(field, 0, THREAD); 536 } UNSAFE_END 537 538 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset1(JNIEnv *env, jobject unsafe, jclass c, jstring name)) { 539 return find_field_offset(c, name, THREAD); 540 } UNSAFE_END 541 542 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) { 543 return find_field_offset(field, 1, THREAD); 544 } UNSAFE_END 545 546 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) { 547 assert(field != NULL, "field must not be NULL"); 548 549 // Note: In this VM implementation, a field address is always a short 550 // offset from the base of a a klass metaobject. Thus, the full dynamic 551 // range of the return type is never used. However, some implementations 552 // might put the static field inside an array shared by many classes, 553 // or even at a fixed address, in which case the address could be quite 554 // large. In that last case, this function would return NULL, since 555 // the address would operate alone, without any base pointer. 556 557 oop reflected = JNIHandles::resolve_non_null(field); 558 oop mirror = java_lang_reflect_Field::clazz(reflected); 559 int modifiers = java_lang_reflect_Field::modifiers(reflected); 560 561 if ((modifiers & JVM_ACC_STATIC) == 0) { 562 THROW_0(vmSymbols::java_lang_IllegalArgumentException()); 563 } 564 565 return JNIHandles::make_local(env, mirror); 566 } UNSAFE_END 567 568 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) { 569 assert(clazz != NULL, "clazz must not be NULL"); 570 571 oop mirror = JNIHandles::resolve_non_null(clazz); 572 573 Klass* klass = java_lang_Class::as_Klass(mirror); 574 if (klass != NULL && klass->should_be_initialized()) { 575 InstanceKlass* k = InstanceKlass::cast(klass); 576 k->initialize(CHECK); 577 } 578 } 579 UNSAFE_END 580 581 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) { 582 assert(clazz != NULL, "clazz must not be NULL"); 583 584 oop mirror = JNIHandles::resolve_non_null(clazz); 585 Klass* klass = java_lang_Class::as_Klass(mirror); 586 587 if (klass != NULL && klass->should_be_initialized()) { 588 return true; 589 } 590 591 return false; 592 } 593 UNSAFE_END 594 595 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) { 596 assert(clazz != NULL, "clazz must not be NULL"); 597 598 oop mirror = JNIHandles::resolve_non_null(clazz); 599 Klass* k = java_lang_Class::as_Klass(mirror); 600 601 if (k == NULL || !k->is_array_klass()) { 602 THROW(vmSymbols::java_lang_InvalidClassException()); 603 } else if (k->is_objArray_klass()) { 604 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT); 605 scale = heapOopSize; 606 } else if (k->is_typeArray_klass()) { 607 TypeArrayKlass* tak = TypeArrayKlass::cast(k); 608 base = tak->array_header_in_bytes(); 609 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok"); 610 scale = (1 << tak->log2_element_size()); 611 } else { 612 ShouldNotReachHere(); 613 } 614 } 615 616 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) { 617 int base = 0, scale = 0; 618 getBaseAndScale(base, scale, clazz, CHECK_0); 619 620 return field_offset_from_byte_offset(base); 621 } UNSAFE_END 622 623 624 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) { 625 int base = 0, scale = 0; 626 getBaseAndScale(base, scale, clazz, CHECK_0); 627 628 // This VM packs both fields and array elements down to the byte. 629 // But watch out: If this changes, so that array references for 630 // a given primitive type (say, T_BOOLEAN) use different memory units 631 // than fields, this method MUST return zero for such arrays. 632 // For example, the VM used to store sub-word sized fields in full 633 // words in the object layout, so that accessors like getByte(Object,int) 634 // did not really do what one might expect for arrays. Therefore, 635 // this function used to report a zero scale factor, so that the user 636 // would know not to attempt to access sub-word array elements. 637 // // Code for unpacked fields: 638 // if (scale < wordSize) return 0; 639 640 // The following allows for a pretty general fieldOffset cookie scheme, 641 // but requires it to be linear in byte offset. 642 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0); 643 } UNSAFE_END 644 645 646 static inline void throw_new(JNIEnv *env, const char *ename) { 647 jclass cls = env->FindClass(ename); 648 if (env->ExceptionCheck()) { 649 env->ExceptionClear(); 650 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", ename); 651 return; 652 } 653 654 env->ThrowNew(cls, NULL); 655 } 656 657 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) { 658 // Code lifted from JDK 1.3 ClassLoader.c 659 660 jbyte *body; 661 char *utfName = NULL; 662 jclass result = 0; 663 char buf[128]; 664 665 assert(data != NULL, "Class bytes must not be NULL"); 666 assert(length >= 0, "length must not be negative: %d", length); 667 668 if (UsePerfData) { 669 ClassLoader::unsafe_defineClassCallCounter()->inc(); 670 } 671 672 body = NEW_C_HEAP_ARRAY_RETURN_NULL(jbyte, length, mtInternal); 673 if (body == NULL) { 674 throw_new(env, "java/lang/OutOfMemoryError"); 675 return 0; 676 } 677 678 env->GetByteArrayRegion(data, offset, length, body); 679 if (env->ExceptionOccurred()) { 680 goto free_body; 681 } 682 683 if (name != NULL) { 684 uint len = env->GetStringUTFLength(name); 685 int unicode_len = env->GetStringLength(name); 686 687 if (len >= sizeof(buf)) { 688 utfName = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len + 1, mtInternal); 689 if (utfName == NULL) { 690 throw_new(env, "java/lang/OutOfMemoryError"); 691 goto free_body; 692 } 693 } else { 694 utfName = buf; 695 } 696 697 env->GetStringUTFRegion(name, 0, unicode_len, utfName); 698 699 for (uint i = 0; i < len; i++) { 700 if (utfName[i] == '.') utfName[i] = '/'; 701 } 702 } 703 704 result = JVM_DefineClass(env, utfName, loader, body, length, pd); 705 706 if (utfName && utfName != buf) { 707 FREE_C_HEAP_ARRAY(char, utfName); 708 } 709 710 free_body: 711 FREE_C_HEAP_ARRAY(jbyte, body); 712 return result; 713 } 714 715 716 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) { 717 ThreadToNativeFromVM ttnfv(thread); 718 719 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd); 720 } UNSAFE_END 721 722 723 // define a class but do not make it known to the class loader or system dictionary 724 // - host_class: supplies context for linkage, access control, protection domain, and class loader 725 // if host_class is itself anonymous then it is replaced with its host class. 726 // - data: bytes of a class file, a raw memory address (length gives the number of bytes) 727 // - cp_patches: where non-null entries exist, they replace corresponding CP entries in data 728 729 // When you load an anonymous class U, it works as if you changed its name just before loading, 730 // to a name that you will never use again. Since the name is lost, no other class can directly 731 // link to any member of U. Just after U is loaded, the only way to use it is reflectively, 732 // through java.lang.Class methods like Class.newInstance. 733 734 // The package of an anonymous class must either match its host's class's package or be in the 735 // unnamed package. If it is in the unnamed package then it will be put in its host class's 736 // package. 737 // 738 739 // Access checks for linkage sites within U continue to follow the same rules as for named classes. 740 // An anonymous class also has special privileges to access any member of its host class. 741 // This is the main reason why this loading operation is unsafe. The purpose of this is to 742 // allow language implementations to simulate "open classes"; a host class in effect gets 743 // new code when an anonymous class is loaded alongside it. A less convenient but more 744 // standard way to do this is with reflection, which can also be set to ignore access 745 // restrictions. 746 747 // Access into an anonymous class is possible only through reflection. Therefore, there 748 // are no special access rules for calling into an anonymous class. The relaxed access 749 // rule for the host class is applied in the opposite direction: A host class reflectively 750 // access one of its anonymous classes. 751 752 // If you load the same bytecodes twice, you get two different classes. You can reload 753 // the same bytecodes with or without varying CP patches. 754 755 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1. 756 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is). 757 // The CONSTANT_Class entry for that name can be patched to refer directly to U1. 758 759 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as 760 // an outer class (so that U2 is an anonymous inner class of anonymous U1). 761 // It is not possible for a named class, or an older anonymous class, to refer by 762 // name (via its CP) to a newer anonymous class. 763 764 // CP patching may also be used to modify (i.e., hack) the names of methods, classes, 765 // or type descriptors used in the loaded anonymous class. 766 767 // Finally, CP patching may be used to introduce "live" objects into the constant pool, 768 // instead of "dead" strings. A compiled statement like println((Object)"hello") can 769 // be changed to println(greeting), where greeting is an arbitrary object created before 770 // the anonymous class is loaded. This is useful in dynamic languages, in which 771 // various kinds of metaobjects must be introduced as constants into bytecode. 772 // Note the cast (Object), which tells the verifier to expect an arbitrary object, 773 // not just a literal string. For such ldc instructions, the verifier uses the 774 // type Object instead of String, if the loaded constant is not in fact a String. 775 776 static InstanceKlass* 777 Unsafe_DefineAnonymousClass_impl(JNIEnv *env, 778 jclass host_class, jbyteArray data, jobjectArray cp_patches_jh, 779 u1** temp_alloc, 780 TRAPS) { 781 assert(host_class != NULL, "host_class must not be NULL"); 782 assert(data != NULL, "data must not be NULL"); 783 784 if (UsePerfData) { 785 ClassLoader::unsafe_defineClassCallCounter()->inc(); 786 } 787 788 jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length(); 789 assert(length >= 0, "class_bytes_length must not be negative: %d", length); 790 791 int class_bytes_length = (int) length; 792 793 u1* class_bytes = NEW_C_HEAP_ARRAY_RETURN_NULL(u1, length, mtInternal); 794 if (class_bytes == NULL) { 795 THROW_0(vmSymbols::java_lang_OutOfMemoryError()); 796 } 797 798 // caller responsible to free it: 799 *temp_alloc = class_bytes; 800 801 ArrayAccess<>::arraycopy_to_native(arrayOop(JNIHandles::resolve_non_null(data)), typeArrayOopDesc::element_offset<jbyte>(0), 802 reinterpret_cast<jbyte*>(class_bytes), length); 803 804 objArrayHandle cp_patches_h; 805 if (cp_patches_jh != NULL) { 806 oop p = JNIHandles::resolve_non_null(cp_patches_jh); 807 assert(p->is_objArray(), "cp_patches must be an object[]"); 808 cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p); 809 } 810 811 const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class)); 812 813 // Make sure it's the real host class, not another anonymous class. 814 while (host_klass != NULL && host_klass->is_instance_klass() && 815 InstanceKlass::cast(host_klass)->is_unsafe_anonymous()) { 816 host_klass = InstanceKlass::cast(host_klass)->unsafe_anonymous_host(); 817 } 818 819 // Primitive types have NULL Klass* fields in their java.lang.Class instances. 820 if (host_klass == NULL) { 821 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Host class is null"); 822 } 823 824 assert(host_klass->is_instance_klass(), "Host class must be an instance class"); 825 826 const char* host_source = host_klass->external_name(); 827 Handle host_loader(THREAD, host_klass->class_loader()); 828 Handle host_domain(THREAD, host_klass->protection_domain()); 829 830 GrowableArray<Handle>* cp_patches = NULL; 831 832 if (cp_patches_h.not_null()) { 833 int alen = cp_patches_h->length(); 834 835 for (int i = alen-1; i >= 0; i--) { 836 oop p = cp_patches_h->obj_at(i); 837 if (p != NULL) { 838 Handle patch(THREAD, p); 839 840 if (cp_patches == NULL) { 841 cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle()); 842 } 843 844 cp_patches->at_put(i, patch); 845 } 846 } 847 } 848 849 ClassFileStream st(class_bytes, class_bytes_length, host_source, ClassFileStream::verify); 850 851 Symbol* no_class_name = NULL; 852 Klass* anonk = SystemDictionary::parse_stream(no_class_name, 853 host_loader, 854 host_domain, 855 &st, 856 InstanceKlass::cast(host_klass), 857 cp_patches, 858 CHECK_NULL); 859 if (anonk == NULL) { 860 return NULL; 861 } 862 863 return InstanceKlass::cast(anonk); 864 } 865 866 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) { 867 ResourceMark rm(THREAD); 868 869 jobject res_jh = NULL; 870 u1* temp_alloc = NULL; 871 872 InstanceKlass* anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data, cp_patches_jh, &temp_alloc, THREAD); 873 if (anon_klass != NULL) { 874 res_jh = JNIHandles::make_local(env, anon_klass->java_mirror()); 875 } 876 877 // try/finally clause: 878 FREE_C_HEAP_ARRAY(u1, temp_alloc); 879 880 // The anonymous class loader data has been artificially been kept alive to 881 // this point. The mirror and any instances of this class have to keep 882 // it alive afterwards. 883 if (anon_klass != NULL) { 884 anon_klass->class_loader_data()->dec_keep_alive(); 885 } 886 887 // let caller initialize it as needed... 888 889 return (jclass) res_jh; 890 } UNSAFE_END 891 892 893 894 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) { 895 ThreadToNativeFromVM ttnfv(thread); 896 env->Throw(thr); 897 } UNSAFE_END 898 899 // JSR166 ------------------------------------------------------------------ 900 901 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) { 902 oop x = JNIHandles::resolve(x_h); 903 oop e = JNIHandles::resolve(e_h); 904 oop p = JNIHandles::resolve(obj); 905 assert_field_offset_sane(p, offset); 906 oop res = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x); 907 return JNIHandles::make_local(env, res); 908 } UNSAFE_END 909 910 UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) { 911 oop p = JNIHandles::resolve(obj); 912 if (p == NULL) { 913 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset); 914 return RawAccess<>::atomic_cmpxchg(addr, e, x); 915 } else { 916 assert_field_offset_sane(p, offset); 917 return HeapAccess<>::atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x); 918 } 919 } UNSAFE_END 920 921 UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) { 922 oop p = JNIHandles::resolve(obj); 923 if (p == NULL) { 924 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset); 925 return RawAccess<>::atomic_cmpxchg(addr, e, x); 926 } else { 927 assert_field_offset_sane(p, offset); 928 return HeapAccess<>::atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x); 929 } 930 } UNSAFE_END 931 932 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetReference(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) { 933 oop x = JNIHandles::resolve(x_h); 934 oop e = JNIHandles::resolve(e_h); 935 oop p = JNIHandles::resolve(obj); 936 assert_field_offset_sane(p, offset); 937 oop ret = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x); 938 return ret == e; 939 } UNSAFE_END 940 941 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) { 942 oop p = JNIHandles::resolve(obj); 943 if (p == NULL) { 944 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset); 945 return RawAccess<>::atomic_cmpxchg(addr, e, x) == e; 946 } else { 947 assert_field_offset_sane(p, offset); 948 return HeapAccess<>::atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x) == e; 949 } 950 } UNSAFE_END 951 952 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) { 953 oop p = JNIHandles::resolve(obj); 954 if (p == NULL) { 955 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset); 956 return RawAccess<>::atomic_cmpxchg(addr, e, x) == e; 957 } else { 958 assert_field_offset_sane(p, offset); 959 return HeapAccess<>::atomic_cmpxchg_at(p, (ptrdiff_t)offset, e, x) == e; 960 } 961 } UNSAFE_END 962 963 static void post_thread_park_event(EventThreadPark* event, const oop obj, jlong timeout_nanos, jlong until_epoch_millis) { 964 assert(event != NULL, "invariant"); 965 assert(event->should_commit(), "invariant"); 966 event->set_parkedClass((obj != NULL) ? obj->klass() : NULL); 967 event->set_timeout(timeout_nanos); 968 event->set_until(until_epoch_millis); 969 event->set_address((obj != NULL) ? (u8)cast_from_oop<uintptr_t>(obj) : 0); 970 event->commit(); 971 } 972 973 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) { 974 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time); 975 EventThreadPark event; 976 977 JavaThreadParkedState jtps(thread, time != 0); 978 thread->parker()->park(isAbsolute != 0, time); 979 if (event.should_commit()) { 980 const oop obj = thread->current_park_blocker(); 981 if (time == 0) { 982 post_thread_park_event(&event, obj, min_jlong, min_jlong); 983 } else { 984 if (isAbsolute != 0) { 985 post_thread_park_event(&event, obj, min_jlong, time); 986 } else { 987 post_thread_park_event(&event, obj, time, min_jlong); 988 } 989 } 990 } 991 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker()); 992 } UNSAFE_END 993 994 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) { 995 Parker* p = NULL; 996 997 if (jthread != NULL) { 998 ThreadsListHandle tlh; 999 JavaThread* thr = NULL; 1000 oop java_thread = NULL; 1001 (void) tlh.cv_internal_thread_to_JavaThread(jthread, &thr, &java_thread); 1002 if (java_thread != NULL) { 1003 // This is a valid oop. 1004 if (thr != NULL) { 1005 // The JavaThread is alive. 1006 p = thr->parker(); 1007 } 1008 } 1009 } // ThreadsListHandle is destroyed here. 1010 1011 // 'p' points to type-stable-memory if non-NULL. If the target 1012 // thread terminates before we get here the new user of this 1013 // Parker will get a 'spurious' unpark - which is perfectly valid. 1014 if (p != NULL) { 1015 HOTSPOT_THREAD_UNPARK((uintptr_t) p); 1016 p->unpark(); 1017 } 1018 } UNSAFE_END 1019 1020 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) { 1021 const int max_nelem = 3; 1022 double la[max_nelem]; 1023 jint ret; 1024 1025 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg)); 1026 assert(a->is_typeArray(), "must be type array"); 1027 1028 ret = os::loadavg(la, nelem); 1029 if (ret == -1) { 1030 return -1; 1031 } 1032 1033 // if successful, ret is the number of samples actually retrieved. 1034 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value"); 1035 switch(ret) { 1036 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through 1037 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through 1038 case 1: a->double_at_put(0, (jdouble)la[0]); break; 1039 } 1040 1041 return ret; 1042 } UNSAFE_END 1043 1044 1045 /// JVM_RegisterUnsafeMethods 1046 1047 #define ADR "J" 1048 1049 #define LANG "Ljava/lang/" 1050 1051 #define OBJ LANG "Object;" 1052 #define CLS LANG "Class;" 1053 #define FLD LANG "reflect/Field;" 1054 #define THR LANG "Throwable;" 1055 1056 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;" 1057 #define DAC_Args CLS "[B[" OBJ 1058 1059 #define CC (char*) /*cast a literal from (const char*)*/ 1060 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f) 1061 1062 #define DECLARE_GETPUTOOP(Type, Desc) \ 1063 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \ 1064 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \ 1065 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \ 1066 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)} 1067 1068 1069 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = { 1070 {CC "getReference", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetReference)}, 1071 {CC "putReference", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReference)}, 1072 {CC "getReferenceVolatile", CC "(" OBJ "J)" OBJ, FN_PTR(Unsafe_GetReferenceVolatile)}, 1073 {CC "putReferenceVolatile", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutReferenceVolatile)}, 1074 1075 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)}, 1076 1077 DECLARE_GETPUTOOP(Boolean, Z), 1078 DECLARE_GETPUTOOP(Byte, B), 1079 DECLARE_GETPUTOOP(Short, S), 1080 DECLARE_GETPUTOOP(Char, C), 1081 DECLARE_GETPUTOOP(Int, I), 1082 DECLARE_GETPUTOOP(Long, J), 1083 DECLARE_GETPUTOOP(Float, F), 1084 DECLARE_GETPUTOOP(Double, D), 1085 1086 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)}, 1087 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)}, 1088 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)}, 1089 1090 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)}, 1091 {CC "objectFieldOffset1", CC "(" CLS LANG "String;)J", FN_PTR(Unsafe_ObjectFieldOffset1)}, 1092 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)}, 1093 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)}, 1094 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)}, 1095 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)}, 1096 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)}, 1097 1098 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)}, 1099 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)}, 1100 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)}, 1101 {CC "compareAndSetReference",CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSetReference)}, 1102 {CC "compareAndSetInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSetInt)}, 1103 {CC "compareAndSetLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSetLong)}, 1104 {CC "compareAndExchangeReference", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeReference)}, 1105 {CC "compareAndExchangeInt", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)}, 1106 {CC "compareAndExchangeLong", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)}, 1107 1108 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)}, 1109 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)}, 1110 1111 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)}, 1112 1113 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)}, 1114 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)}, 1115 {CC "writeback0", CC "(" "J" ")V", FN_PTR(Unsafe_WriteBack0)}, 1116 {CC "writebackPreSync0", CC "()V", FN_PTR(Unsafe_WriteBackPreSync0)}, 1117 {CC "writebackPostSync0", CC "()V", FN_PTR(Unsafe_WriteBackPostSync0)}, 1118 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)}, 1119 1120 {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)}, 1121 1122 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)}, 1123 1124 {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)}, 1125 {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)}, 1126 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)}, 1127 }; 1128 1129 #undef CC 1130 #undef FN_PTR 1131 1132 #undef ADR 1133 #undef LANG 1134 #undef OBJ 1135 #undef CLS 1136 #undef FLD 1137 #undef THR 1138 #undef DC_Args 1139 #undef DAC_Args 1140 1141 #undef DECLARE_GETPUTOOP 1142 1143 1144 // This function is exported, used by NativeLookup. 1145 // The Unsafe_xxx functions above are called only from the interpreter. 1146 // The optimizer looks at names and signatures to recognize 1147 // individual functions. 1148 1149 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) { 1150 ThreadToNativeFromVM ttnfv(thread); 1151 1152 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod)); 1153 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives"); 1154 } JVM_END