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