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