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 "memory/allocation.inline.hpp" 31 #include "memory/resourceArea.hpp" 32 #include "oops/access.inline.hpp" 33 #include "oops/fieldStreams.hpp" 34 #include "oops/objArrayOop.inline.hpp" 35 #include "oops/oop.inline.hpp" 36 #include "oops/typeArrayOop.inline.hpp" 37 #include "prims/unsafe.hpp" 38 #include "runtime/atomic.hpp" 39 #include "runtime/globals.hpp" 40 #include "runtime/interfaceSupport.hpp" 41 #include "runtime/jniHandles.inline.hpp" 42 #include "runtime/orderAccess.inline.hpp" 43 #include "runtime/reflection.hpp" 44 #include "runtime/thread.hpp" 45 #include "runtime/threadSMR.hpp" 46 #include "runtime/vm_version.hpp" 47 #include "services/threadService.hpp" 48 #include "trace/tracing.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 (sizeof(char*) == sizeof(jint)) { // (this constant folds!) 127 return (address)p + (jint) byte_offset; 128 } else { 129 return (address)p + byte_offset; 130 } 131 } 132 133 // Externally callable versions: 134 // (Use these in compiler intrinsics which emulate unsafe primitives.) 135 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) { 136 return field_offset; 137 } 138 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) { 139 return byte_offset; 140 } 141 142 143 ///// Data read/writes on the Java heap and in native (off-heap) memory 144 145 /** 146 * Helper class for accessing memory. 147 * 148 * Normalizes values and wraps accesses in 149 * JavaThread::doing_unsafe_access() if needed. 150 */ 151 template <typename T> 152 class MemoryAccess : StackObj { 153 JavaThread* _thread; 154 oop _obj; 155 ptrdiff_t _offset; 156 157 // Resolves and returns the address of the memory access. 158 // This raw memory access may fault, so we make sure it happens within the 159 // guarded scope by making the access volatile at least. Since the store 160 // of Thread::set_doing_unsafe_access() is also volatile, these accesses 161 // can not be reordered by the compiler. Therefore, if the access triggers 162 // a fault, we will know that Thread::doing_unsafe_access() returns true. 163 volatile T* addr() { 164 void* addr = index_oop_from_field_offset_long(_obj, _offset); 165 return static_cast<volatile T*>(addr); 166 } 167 168 template <typename U> 169 U normalize_for_write(U x) { 170 return x; 171 } 172 173 jboolean normalize_for_write(jboolean x) { 174 return x & 1; 175 } 176 177 template <typename U> 178 U normalize_for_read(U x) { 179 return x; 180 } 181 182 jboolean normalize_for_read(jboolean x) { 183 return x != 0; 184 } 185 186 /** 187 * Helper class to wrap memory accesses in JavaThread::doing_unsafe_access() 188 */ 189 class GuardUnsafeAccess { 190 JavaThread* _thread; 191 192 public: 193 GuardUnsafeAccess(JavaThread* thread) : _thread(thread) { 194 // native/off-heap access which may raise SIGBUS if accessing 195 // memory mapped file data in a region of the file which has 196 // been truncated and is now invalid 197 _thread->set_doing_unsafe_access(true); 198 } 199 200 ~GuardUnsafeAccess() { 201 _thread->set_doing_unsafe_access(false); 202 } 203 }; 204 205 public: 206 MemoryAccess(JavaThread* thread, jobject obj, jlong offset) 207 : _thread(thread), _obj(JNIHandles::resolve(obj)), _offset((ptrdiff_t)offset) { 208 assert_field_offset_sane(_obj, offset); 209 } 210 211 T get() { 212 if (oopDesc::is_null(_obj)) { 213 GuardUnsafeAccess guard(_thread); 214 T ret = RawAccess<>::load(addr()); 215 return normalize_for_read(ret); 216 } else { 217 T ret = HeapAccess<>::load_at(_obj, _offset); 218 return normalize_for_read(ret); 219 } 220 } 221 222 void put(T x) { 223 if (oopDesc::is_null(_obj)) { 224 GuardUnsafeAccess guard(_thread); 225 RawAccess<>::store(addr(), normalize_for_write(x)); 226 } else { 227 HeapAccess<>::store_at(_obj, _offset, normalize_for_write(x)); 228 } 229 } 230 231 232 T get_volatile() { 233 if (oopDesc::is_null(_obj)) { 234 GuardUnsafeAccess guard(_thread); 235 volatile T ret = RawAccess<MO_SEQ_CST>::load(addr()); 236 return normalize_for_read(ret); 237 } else { 238 T ret = HeapAccess<MO_SEQ_CST>::load_at(_obj, _offset); 239 return normalize_for_read(ret); 240 } 241 } 242 243 void put_volatile(T x) { 244 if (oopDesc::is_null(_obj)) { 245 GuardUnsafeAccess guard(_thread); 246 RawAccess<MO_SEQ_CST>::store(addr(), normalize_for_write(x)); 247 } else { 248 HeapAccess<MO_SEQ_CST>::store_at(_obj, _offset, normalize_for_write(x)); 249 } 250 } 251 }; 252 253 // These functions allow a null base pointer with an arbitrary address. 254 // But if the base pointer is non-null, the offset should make some sense. 255 // That is, it should be in the range [0, MAX_OBJECT_SIZE]. 256 UNSAFE_ENTRY(jobject, Unsafe_GetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { 257 oop p = JNIHandles::resolve(obj); 258 assert_field_offset_sane(p, offset); 259 oop v = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset); 260 return JNIHandles::make_local(env, v); 261 } UNSAFE_END 262 263 UNSAFE_ENTRY(void, Unsafe_PutObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) { 264 oop x = JNIHandles::resolve(x_h); 265 oop p = JNIHandles::resolve(obj); 266 assert_field_offset_sane(p, offset); 267 HeapAccess<ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x); 268 } UNSAFE_END 269 270 UNSAFE_ENTRY(jobject, Unsafe_GetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { 271 oop p = JNIHandles::resolve(obj); 272 assert_field_offset_sane(p, offset); 273 oop v = HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_load_at(p, offset); 274 return JNIHandles::make_local(env, v); 275 } UNSAFE_END 276 277 UNSAFE_ENTRY(void, Unsafe_PutObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h)) { 278 oop x = JNIHandles::resolve(x_h); 279 oop p = JNIHandles::resolve(obj); 280 assert_field_offset_sane(p, offset); 281 HeapAccess<MO_SEQ_CST | ON_UNKNOWN_OOP_REF>::oop_store_at(p, offset, x); 282 } UNSAFE_END 283 284 UNSAFE_ENTRY(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) { 285 oop v = *(oop*) (address) addr; 286 return JNIHandles::make_local(env, v); 287 } UNSAFE_END 288 289 UNSAFE_LEAF(jboolean, Unsafe_isBigEndian0(JNIEnv *env, jobject unsafe)) { 290 #ifdef VM_LITTLE_ENDIAN 291 return false; 292 #else 293 return true; 294 #endif 295 } UNSAFE_END 296 297 UNSAFE_LEAF(jint, Unsafe_unalignedAccess0(JNIEnv *env, jobject unsafe)) { 298 return UseUnalignedAccesses; 299 } UNSAFE_END 300 301 #define DEFINE_GETSETOOP(java_type, Type) \ 302 \ 303 UNSAFE_ENTRY(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \ 304 return MemoryAccess<java_type>(thread, obj, offset).get(); \ 305 } UNSAFE_END \ 306 \ 307 UNSAFE_ENTRY(void, Unsafe_Put##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \ 308 MemoryAccess<java_type>(thread, obj, offset).put(x); \ 309 } UNSAFE_END \ 310 \ 311 // END DEFINE_GETSETOOP. 312 313 DEFINE_GETSETOOP(jboolean, Boolean) 314 DEFINE_GETSETOOP(jbyte, Byte) 315 DEFINE_GETSETOOP(jshort, Short); 316 DEFINE_GETSETOOP(jchar, Char); 317 DEFINE_GETSETOOP(jint, Int); 318 DEFINE_GETSETOOP(jlong, Long); 319 DEFINE_GETSETOOP(jfloat, Float); 320 DEFINE_GETSETOOP(jdouble, Double); 321 322 #undef DEFINE_GETSETOOP 323 324 #define DEFINE_GETSETOOP_VOLATILE(java_type, Type) \ 325 \ 326 UNSAFE_ENTRY(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \ 327 return MemoryAccess<java_type>(thread, obj, offset).get_volatile(); \ 328 } UNSAFE_END \ 329 \ 330 UNSAFE_ENTRY(void, Unsafe_Put##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \ 331 MemoryAccess<java_type>(thread, obj, offset).put_volatile(x); \ 332 } UNSAFE_END \ 333 \ 334 // END DEFINE_GETSETOOP_VOLATILE. 335 336 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean) 337 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte) 338 DEFINE_GETSETOOP_VOLATILE(jshort, Short); 339 DEFINE_GETSETOOP_VOLATILE(jchar, Char); 340 DEFINE_GETSETOOP_VOLATILE(jint, Int); 341 DEFINE_GETSETOOP_VOLATILE(jlong, Long); 342 DEFINE_GETSETOOP_VOLATILE(jfloat, Float); 343 DEFINE_GETSETOOP_VOLATILE(jdouble, Double); 344 345 #undef DEFINE_GETSETOOP_VOLATILE 346 347 UNSAFE_LEAF(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe)) { 348 OrderAccess::acquire(); 349 } UNSAFE_END 350 351 UNSAFE_LEAF(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe)) { 352 OrderAccess::release(); 353 } UNSAFE_END 354 355 UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) { 356 OrderAccess::fence(); 357 } UNSAFE_END 358 359 ////// Allocation requests 360 361 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls)) { 362 ThreadToNativeFromVM ttnfv(thread); 363 return env->AllocObject(cls); 364 } UNSAFE_END 365 366 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) { 367 size_t sz = (size_t)size; 368 369 sz = align_up(sz, HeapWordSize); 370 void* x = os::malloc(sz, mtInternal); 371 372 return addr_to_java(x); 373 } UNSAFE_END 374 375 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) { 376 void* p = addr_from_java(addr); 377 size_t sz = (size_t)size; 378 sz = align_up(sz, HeapWordSize); 379 380 void* x = os::realloc(p, sz, mtInternal); 381 382 return addr_to_java(x); 383 } UNSAFE_END 384 385 UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) { 386 void* p = addr_from_java(addr); 387 388 os::free(p); 389 } UNSAFE_END 390 391 UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) { 392 size_t sz = (size_t)size; 393 394 oop base = JNIHandles::resolve(obj); 395 void* p = index_oop_from_field_offset_long(base, offset); 396 397 Copy::fill_to_memory_atomic(p, sz, value); 398 } UNSAFE_END 399 400 UNSAFE_ENTRY(void, Unsafe_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) { 401 size_t sz = (size_t)size; 402 403 oop srcp = JNIHandles::resolve(srcObj); 404 oop dstp = JNIHandles::resolve(dstObj); 405 406 void* src = index_oop_from_field_offset_long(srcp, srcOffset); 407 void* dst = index_oop_from_field_offset_long(dstp, dstOffset); 408 409 Copy::conjoint_memory_atomic(src, dst, sz); 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 Copy::conjoint_swap(src, dst, sz, esz); 426 } else { 427 // At least one of src/dst are on heap, transition to VM to access raw pointers 428 429 JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) { 430 oop srcp = JNIHandles::resolve(srcObj); 431 oop dstp = JNIHandles::resolve(dstObj); 432 433 address src = (address)index_oop_from_field_offset_long(srcp, srcOffset); 434 address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset); 435 436 Copy::conjoint_swap(src, dst, sz, esz); 437 } JVM_END 438 } 439 } UNSAFE_END 440 441 ////// Random queries 442 443 UNSAFE_LEAF(jint, Unsafe_AddressSize0(JNIEnv *env, jobject unsafe)) { 444 return sizeof(void*); 445 } UNSAFE_END 446 447 UNSAFE_LEAF(jint, Unsafe_PageSize()) { 448 return os::vm_page_size(); 449 } UNSAFE_END 450 451 static jlong find_field_offset(jclass clazz, jstring name, TRAPS) { 452 assert(clazz != NULL, "clazz must not be NULL"); 453 assert(name != NULL, "name must not be NULL"); 454 455 ResourceMark rm(THREAD); 456 char *utf_name = java_lang_String::as_utf8_string(JNIHandles::resolve_non_null(name)); 457 458 InstanceKlass* k = InstanceKlass::cast(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(clazz))); 459 460 jint offset = -1; 461 for (JavaFieldStream fs(k); !fs.done(); fs.next()) { 462 Symbol *name = fs.name(); 463 if (name->equals(utf_name)) { 464 offset = fs.offset(); 465 break; 466 } 467 } 468 if (offset < 0) { 469 THROW_0(vmSymbols::java_lang_InternalError()); 470 } 471 return field_offset_from_byte_offset(offset); 472 } 473 474 static jlong find_field_offset(jobject field, int must_be_static, TRAPS) { 475 assert(field != NULL, "field must not be NULL"); 476 477 oop reflected = JNIHandles::resolve_non_null(field); 478 oop mirror = java_lang_reflect_Field::clazz(reflected); 479 Klass* k = java_lang_Class::as_Klass(mirror); 480 int slot = java_lang_reflect_Field::slot(reflected); 481 int modifiers = java_lang_reflect_Field::modifiers(reflected); 482 483 if (must_be_static >= 0) { 484 int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0); 485 if (must_be_static != really_is_static) { 486 THROW_0(vmSymbols::java_lang_IllegalArgumentException()); 487 } 488 } 489 490 int offset = InstanceKlass::cast(k)->field_offset(slot); 491 return field_offset_from_byte_offset(offset); 492 } 493 494 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) { 495 return find_field_offset(field, 0, THREAD); 496 } UNSAFE_END 497 498 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset1(JNIEnv *env, jobject unsafe, jclass c, jstring name)) { 499 return find_field_offset(c, name, THREAD); 500 } UNSAFE_END 501 502 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) { 503 return find_field_offset(field, 1, THREAD); 504 } UNSAFE_END 505 506 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) { 507 assert(field != NULL, "field must not be NULL"); 508 509 // Note: In this VM implementation, a field address is always a short 510 // offset from the base of a a klass metaobject. Thus, the full dynamic 511 // range of the return type is never used. However, some implementations 512 // might put the static field inside an array shared by many classes, 513 // or even at a fixed address, in which case the address could be quite 514 // large. In that last case, this function would return NULL, since 515 // the address would operate alone, without any base pointer. 516 517 oop reflected = JNIHandles::resolve_non_null(field); 518 oop mirror = java_lang_reflect_Field::clazz(reflected); 519 int modifiers = java_lang_reflect_Field::modifiers(reflected); 520 521 if ((modifiers & JVM_ACC_STATIC) == 0) { 522 THROW_0(vmSymbols::java_lang_IllegalArgumentException()); 523 } 524 525 return JNIHandles::make_local(env, mirror); 526 } UNSAFE_END 527 528 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) { 529 assert(clazz != NULL, "clazz must not be NULL"); 530 531 oop mirror = JNIHandles::resolve_non_null(clazz); 532 533 Klass* klass = java_lang_Class::as_Klass(mirror); 534 if (klass != NULL && klass->should_be_initialized()) { 535 InstanceKlass* k = InstanceKlass::cast(klass); 536 k->initialize(CHECK); 537 } 538 } 539 UNSAFE_END 540 541 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) { 542 assert(clazz != NULL, "clazz must not be NULL"); 543 544 oop mirror = JNIHandles::resolve_non_null(clazz); 545 Klass* klass = java_lang_Class::as_Klass(mirror); 546 547 if (klass != NULL && klass->should_be_initialized()) { 548 return true; 549 } 550 551 return false; 552 } 553 UNSAFE_END 554 555 static void getBaseAndScale(int& base, int& scale, jclass clazz, TRAPS) { 556 assert(clazz != NULL, "clazz must not be NULL"); 557 558 oop mirror = JNIHandles::resolve_non_null(clazz); 559 Klass* k = java_lang_Class::as_Klass(mirror); 560 561 if (k == NULL || !k->is_array_klass()) { 562 THROW(vmSymbols::java_lang_InvalidClassException()); 563 } else if (k->is_objArray_klass()) { 564 base = arrayOopDesc::base_offset_in_bytes(T_OBJECT); 565 scale = heapOopSize; 566 } else if (k->is_typeArray_klass()) { 567 TypeArrayKlass* tak = TypeArrayKlass::cast(k); 568 base = tak->array_header_in_bytes(); 569 assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok"); 570 scale = (1 << tak->log2_element_size()); 571 } else { 572 ShouldNotReachHere(); 573 } 574 } 575 576 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) { 577 int base = 0, scale = 0; 578 getBaseAndScale(base, scale, clazz, CHECK_0); 579 580 return field_offset_from_byte_offset(base); 581 } UNSAFE_END 582 583 584 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) { 585 int base = 0, scale = 0; 586 getBaseAndScale(base, scale, clazz, CHECK_0); 587 588 // This VM packs both fields and array elements down to the byte. 589 // But watch out: If this changes, so that array references for 590 // a given primitive type (say, T_BOOLEAN) use different memory units 591 // than fields, this method MUST return zero for such arrays. 592 // For example, the VM used to store sub-word sized fields in full 593 // words in the object layout, so that accessors like getByte(Object,int) 594 // did not really do what one might expect for arrays. Therefore, 595 // this function used to report a zero scale factor, so that the user 596 // would know not to attempt to access sub-word array elements. 597 // // Code for unpacked fields: 598 // if (scale < wordSize) return 0; 599 600 // The following allows for a pretty general fieldOffset cookie scheme, 601 // but requires it to be linear in byte offset. 602 return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0); 603 } UNSAFE_END 604 605 606 static inline void throw_new(JNIEnv *env, const char *ename) { 607 jclass cls = env->FindClass(ename); 608 if (env->ExceptionCheck()) { 609 env->ExceptionClear(); 610 tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", ename); 611 return; 612 } 613 614 env->ThrowNew(cls, NULL); 615 } 616 617 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) { 618 // Code lifted from JDK 1.3 ClassLoader.c 619 620 jbyte *body; 621 char *utfName = NULL; 622 jclass result = 0; 623 char buf[128]; 624 625 assert(data != NULL, "Class bytes must not be NULL"); 626 assert(length >= 0, "length must not be negative: %d", length); 627 628 if (UsePerfData) { 629 ClassLoader::unsafe_defineClassCallCounter()->inc(); 630 } 631 632 body = NEW_C_HEAP_ARRAY(jbyte, length, mtInternal); 633 if (body == NULL) { 634 throw_new(env, "java/lang/OutOfMemoryError"); 635 return 0; 636 } 637 638 env->GetByteArrayRegion(data, offset, length, body); 639 if (env->ExceptionOccurred()) { 640 goto free_body; 641 } 642 643 if (name != NULL) { 644 uint len = env->GetStringUTFLength(name); 645 int unicode_len = env->GetStringLength(name); 646 647 if (len >= sizeof(buf)) { 648 utfName = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal); 649 if (utfName == NULL) { 650 throw_new(env, "java/lang/OutOfMemoryError"); 651 goto free_body; 652 } 653 } else { 654 utfName = buf; 655 } 656 657 env->GetStringUTFRegion(name, 0, unicode_len, utfName); 658 659 for (uint i = 0; i < len; i++) { 660 if (utfName[i] == '.') utfName[i] = '/'; 661 } 662 } 663 664 result = JVM_DefineClass(env, utfName, loader, body, length, pd); 665 666 if (utfName && utfName != buf) { 667 FREE_C_HEAP_ARRAY(char, utfName); 668 } 669 670 free_body: 671 FREE_C_HEAP_ARRAY(jbyte, body); 672 return result; 673 } 674 675 676 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) { 677 ThreadToNativeFromVM ttnfv(thread); 678 679 return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd); 680 } UNSAFE_END 681 682 683 // define a class but do not make it known to the class loader or system dictionary 684 // - host_class: supplies context for linkage, access control, protection domain, and class loader 685 // if host_class is itself anonymous then it is replaced with its host class. 686 // - data: bytes of a class file, a raw memory address (length gives the number of bytes) 687 // - cp_patches: where non-null entries exist, they replace corresponding CP entries in data 688 689 // When you load an anonymous class U, it works as if you changed its name just before loading, 690 // to a name that you will never use again. Since the name is lost, no other class can directly 691 // link to any member of U. Just after U is loaded, the only way to use it is reflectively, 692 // through java.lang.Class methods like Class.newInstance. 693 694 // The package of an anonymous class must either match its host's class's package or be in the 695 // unnamed package. If it is in the unnamed package then it will be put in its host class's 696 // package. 697 // 698 699 // Access checks for linkage sites within U continue to follow the same rules as for named classes. 700 // An anonymous class also has special privileges to access any member of its host class. 701 // This is the main reason why this loading operation is unsafe. The purpose of this is to 702 // allow language implementations to simulate "open classes"; a host class in effect gets 703 // new code when an anonymous class is loaded alongside it. A less convenient but more 704 // standard way to do this is with reflection, which can also be set to ignore access 705 // restrictions. 706 707 // Access into an anonymous class is possible only through reflection. Therefore, there 708 // are no special access rules for calling into an anonymous class. The relaxed access 709 // rule for the host class is applied in the opposite direction: A host class reflectively 710 // access one of its anonymous classes. 711 712 // If you load the same bytecodes twice, you get two different classes. You can reload 713 // the same bytecodes with or without varying CP patches. 714 715 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1. 716 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is). 717 // The CONSTANT_Class entry for that name can be patched to refer directly to U1. 718 719 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as 720 // an outer class (so that U2 is an anonymous inner class of anonymous U1). 721 // It is not possible for a named class, or an older anonymous class, to refer by 722 // name (via its CP) to a newer anonymous class. 723 724 // CP patching may also be used to modify (i.e., hack) the names of methods, classes, 725 // or type descriptors used in the loaded anonymous class. 726 727 // Finally, CP patching may be used to introduce "live" objects into the constant pool, 728 // instead of "dead" strings. A compiled statement like println((Object)"hello") can 729 // be changed to println(greeting), where greeting is an arbitrary object created before 730 // the anonymous class is loaded. This is useful in dynamic languages, in which 731 // various kinds of metaobjects must be introduced as constants into bytecode. 732 // Note the cast (Object), which tells the verifier to expect an arbitrary object, 733 // not just a literal string. For such ldc instructions, the verifier uses the 734 // type Object instead of String, if the loaded constant is not in fact a String. 735 736 static InstanceKlass* 737 Unsafe_DefineAnonymousClass_impl(JNIEnv *env, 738 jclass host_class, jbyteArray data, jobjectArray cp_patches_jh, 739 u1** temp_alloc, 740 TRAPS) { 741 assert(host_class != NULL, "host_class must not be NULL"); 742 assert(data != NULL, "data must not be NULL"); 743 744 if (UsePerfData) { 745 ClassLoader::unsafe_defineClassCallCounter()->inc(); 746 } 747 748 jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length(); 749 assert(length >= 0, "class_bytes_length must not be negative: %d", length); 750 751 int class_bytes_length = (int) length; 752 753 u1* class_bytes = NEW_C_HEAP_ARRAY(u1, length, mtInternal); 754 if (class_bytes == NULL) { 755 THROW_0(vmSymbols::java_lang_OutOfMemoryError()); 756 } 757 758 // caller responsible to free it: 759 *temp_alloc = class_bytes; 760 761 jbyte* array_base = typeArrayOop(JNIHandles::resolve_non_null(data))->byte_at_addr(0); 762 Copy::conjoint_jbytes(array_base, class_bytes, length); 763 764 objArrayHandle cp_patches_h; 765 if (cp_patches_jh != NULL) { 766 oop p = JNIHandles::resolve_non_null(cp_patches_jh); 767 assert(p->is_objArray(), "cp_patches must be an object[]"); 768 cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p); 769 } 770 771 const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class)); 772 773 // Make sure it's the real host class, not another anonymous class. 774 while (host_klass != NULL && host_klass->is_instance_klass() && 775 InstanceKlass::cast(host_klass)->is_anonymous()) { 776 host_klass = InstanceKlass::cast(host_klass)->host_klass(); 777 } 778 779 // Primitive types have NULL Klass* fields in their java.lang.Class instances. 780 if (host_klass == NULL) { 781 THROW_MSG_0(vmSymbols::java_lang_IllegalArgumentException(), "Host class is null"); 782 } 783 784 assert(host_klass->is_instance_klass(), "Host class must be an instance class"); 785 786 const char* host_source = host_klass->external_name(); 787 Handle host_loader(THREAD, host_klass->class_loader()); 788 Handle host_domain(THREAD, host_klass->protection_domain()); 789 790 GrowableArray<Handle>* cp_patches = NULL; 791 792 if (cp_patches_h.not_null()) { 793 int alen = cp_patches_h->length(); 794 795 for (int i = alen-1; i >= 0; i--) { 796 oop p = cp_patches_h->obj_at(i); 797 if (p != NULL) { 798 Handle patch(THREAD, p); 799 800 if (cp_patches == NULL) { 801 cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle()); 802 } 803 804 cp_patches->at_put(i, patch); 805 } 806 } 807 } 808 809 ClassFileStream st(class_bytes, class_bytes_length, host_source, ClassFileStream::verify); 810 811 Symbol* no_class_name = NULL; 812 Klass* anonk = SystemDictionary::parse_stream(no_class_name, 813 host_loader, 814 host_domain, 815 &st, 816 InstanceKlass::cast(host_klass), 817 cp_patches, 818 CHECK_NULL); 819 if (anonk == NULL) { 820 return NULL; 821 } 822 823 return InstanceKlass::cast(anonk); 824 } 825 826 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) { 827 ResourceMark rm(THREAD); 828 829 jobject res_jh = NULL; 830 u1* temp_alloc = NULL; 831 832 InstanceKlass* anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data, cp_patches_jh, &temp_alloc, THREAD); 833 if (anon_klass != NULL) { 834 res_jh = JNIHandles::make_local(env, anon_klass->java_mirror()); 835 } 836 837 // try/finally clause: 838 if (temp_alloc != NULL) { 839 FREE_C_HEAP_ARRAY(u1, temp_alloc); 840 } 841 842 // The anonymous class loader data has been artificially been kept alive to 843 // this point. The mirror and any instances of this class have to keep 844 // it alive afterwards. 845 if (anon_klass != NULL) { 846 anon_klass->class_loader_data()->dec_keep_alive(); 847 } 848 849 // let caller initialize it as needed... 850 851 return (jclass) res_jh; 852 } UNSAFE_END 853 854 855 856 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) { 857 ThreadToNativeFromVM ttnfv(thread); 858 env->Throw(thr); 859 } UNSAFE_END 860 861 // JSR166 ------------------------------------------------------------------ 862 863 UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) { 864 oop x = JNIHandles::resolve(x_h); 865 oop e = JNIHandles::resolve(e_h); 866 oop p = JNIHandles::resolve(obj); 867 assert_field_offset_sane(p, offset); 868 oop res = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e); 869 return JNIHandles::make_local(env, res); 870 } UNSAFE_END 871 872 UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) { 873 oop p = JNIHandles::resolve(obj); 874 if (oopDesc::is_null(p)) { 875 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset); 876 return RawAccess<>::atomic_cmpxchg(x, addr, e); 877 } else { 878 assert_field_offset_sane(p, offset); 879 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e); 880 } 881 } UNSAFE_END 882 883 UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) { 884 oop p = JNIHandles::resolve(obj); 885 if (oopDesc::is_null(p)) { 886 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset); 887 return RawAccess<>::atomic_cmpxchg(x, addr, e); 888 } else { 889 assert_field_offset_sane(p, offset); 890 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e); 891 } 892 } UNSAFE_END 893 894 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) { 895 oop x = JNIHandles::resolve(x_h); 896 oop e = JNIHandles::resolve(e_h); 897 oop p = JNIHandles::resolve(obj); 898 assert_field_offset_sane(p, offset); 899 oop ret = HeapAccess<ON_UNKNOWN_OOP_REF>::oop_atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e); 900 return ret == e; 901 } UNSAFE_END 902 903 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) { 904 oop p = JNIHandles::resolve(obj); 905 if (oopDesc::is_null(p)) { 906 volatile jint* addr = (volatile jint*)index_oop_from_field_offset_long(p, offset); 907 return RawAccess<>::atomic_cmpxchg(x, addr, e) == e; 908 } else { 909 assert_field_offset_sane(p, offset); 910 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e) == e; 911 } 912 } UNSAFE_END 913 914 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSetLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) { 915 oop p = JNIHandles::resolve(obj); 916 if (oopDesc::is_null(p)) { 917 volatile jlong* addr = (volatile jlong*)index_oop_from_field_offset_long(p, offset); 918 return RawAccess<>::atomic_cmpxchg(x, addr, e) == e; 919 } else { 920 assert_field_offset_sane(p, offset); 921 return HeapAccess<>::atomic_cmpxchg_at(x, p, (ptrdiff_t)offset, e) == e; 922 } 923 } UNSAFE_END 924 925 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) { 926 EventThreadPark event; 927 HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time); 928 929 JavaThreadParkedState jtps(thread, time != 0); 930 thread->parker()->park(isAbsolute != 0, time); 931 932 HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker()); 933 934 if (event.should_commit()) { 935 oop obj = thread->current_park_blocker(); 936 event.set_parkedClass((obj != NULL) ? obj->klass() : NULL); 937 event.set_timeout(time); 938 event.set_address((obj != NULL) ? (TYPE_ADDRESS) cast_from_oop<uintptr_t>(obj) : 0); 939 event.commit(); 940 } 941 } UNSAFE_END 942 943 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread)) { 944 Parker* p = NULL; 945 946 if (jthread != NULL) { 947 ThreadsListHandle tlh; 948 JavaThread* thr = NULL; 949 oop java_thread = NULL; 950 (void) tlh.cv_internal_thread_to_JavaThread(jthread, &thr, &java_thread); 951 if (java_thread != NULL) { 952 // This is a valid oop. 953 jlong lp = java_lang_Thread::park_event(java_thread); 954 if (lp != 0) { 955 // This cast is OK even though the jlong might have been read 956 // non-atomically on 32bit systems, since there, one word will 957 // always be zero anyway and the value set is always the same 958 p = (Parker*)addr_from_java(lp); 959 } else { 960 // Not cached in the java.lang.Thread oop yet (could be an 961 // older version of library). 962 if (thr != NULL) { 963 // The JavaThread is alive. 964 p = thr->parker(); 965 if (p != NULL) { 966 // Cache the Parker in the java.lang.Thread oop for next time. 967 java_lang_Thread::set_park_event(java_thread, addr_to_java(p)); 968 } 969 } 970 } 971 } 972 } // ThreadsListHandle is destroyed here. 973 974 if (p != NULL) { 975 HOTSPOT_THREAD_UNPARK((uintptr_t) p); 976 p->unpark(); 977 } 978 } UNSAFE_END 979 980 UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) { 981 const int max_nelem = 3; 982 double la[max_nelem]; 983 jint ret; 984 985 typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg)); 986 assert(a->is_typeArray(), "must be type array"); 987 988 ret = os::loadavg(la, nelem); 989 if (ret == -1) { 990 return -1; 991 } 992 993 // if successful, ret is the number of samples actually retrieved. 994 assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value"); 995 switch(ret) { 996 case 3: a->double_at_put(2, (jdouble)la[2]); // fall through 997 case 2: a->double_at_put(1, (jdouble)la[1]); // fall through 998 case 1: a->double_at_put(0, (jdouble)la[0]); break; 999 } 1000 1001 return ret; 1002 } UNSAFE_END 1003 1004 1005 /// JVM_RegisterUnsafeMethods 1006 1007 #define ADR "J" 1008 1009 #define LANG "Ljava/lang/" 1010 1011 #define OBJ LANG "Object;" 1012 #define CLS LANG "Class;" 1013 #define FLD LANG "reflect/Field;" 1014 #define THR LANG "Throwable;" 1015 1016 #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;" 1017 #define DAC_Args CLS "[B[" OBJ 1018 1019 #define CC (char*) /*cast a literal from (const char*)*/ 1020 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f) 1021 1022 #define DECLARE_GETPUTOOP(Type, Desc) \ 1023 {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \ 1024 {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type)}, \ 1025 {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \ 1026 {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Put##Type##Volatile)} 1027 1028 1029 static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = { 1030 {CC "getObject", CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObject)}, 1031 {CC "putObject", CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutObject)}, 1032 {CC "getObjectVolatile",CC "(" OBJ "J)" OBJ "", FN_PTR(Unsafe_GetObjectVolatile)}, 1033 {CC "putObjectVolatile",CC "(" OBJ "J" OBJ ")V", FN_PTR(Unsafe_PutObjectVolatile)}, 1034 1035 {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)}, 1036 1037 DECLARE_GETPUTOOP(Boolean, Z), 1038 DECLARE_GETPUTOOP(Byte, B), 1039 DECLARE_GETPUTOOP(Short, S), 1040 DECLARE_GETPUTOOP(Char, C), 1041 DECLARE_GETPUTOOP(Int, I), 1042 DECLARE_GETPUTOOP(Long, J), 1043 DECLARE_GETPUTOOP(Float, F), 1044 DECLARE_GETPUTOOP(Double, D), 1045 1046 {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)}, 1047 {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)}, 1048 {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)}, 1049 1050 {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)}, 1051 {CC "objectFieldOffset1", CC "(" CLS LANG "String;)J", FN_PTR(Unsafe_ObjectFieldOffset1)}, 1052 {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)}, 1053 {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)}, 1054 {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)}, 1055 {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)}, 1056 {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)}, 1057 {CC "addressSize0", CC "()I", FN_PTR(Unsafe_AddressSize0)}, 1058 {CC "pageSize", CC "()I", FN_PTR(Unsafe_PageSize)}, 1059 1060 {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)}, 1061 {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)}, 1062 {CC "throwException", CC "(" THR ")V", FN_PTR(Unsafe_ThrowException)}, 1063 {CC "compareAndSetObject",CC "(" OBJ "J" OBJ "" OBJ ")Z", FN_PTR(Unsafe_CompareAndSetObject)}, 1064 {CC "compareAndSetInt", CC "(" OBJ "J""I""I"")Z", FN_PTR(Unsafe_CompareAndSetInt)}, 1065 {CC "compareAndSetLong", CC "(" OBJ "J""J""J"")Z", FN_PTR(Unsafe_CompareAndSetLong)}, 1066 {CC "compareAndExchangeObject", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeObject)}, 1067 {CC "compareAndExchangeInt", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)}, 1068 {CC "compareAndExchangeLong", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)}, 1069 1070 {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)}, 1071 {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)}, 1072 1073 {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)}, 1074 1075 {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)}, 1076 {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)}, 1077 {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)}, 1078 1079 {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)}, 1080 1081 {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)}, 1082 1083 {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)}, 1084 {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)}, 1085 {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)}, 1086 1087 {CC "isBigEndian0", CC "()Z", FN_PTR(Unsafe_isBigEndian0)}, 1088 {CC "unalignedAccess0", CC "()Z", FN_PTR(Unsafe_unalignedAccess0)} 1089 }; 1090 1091 #undef CC 1092 #undef FN_PTR 1093 1094 #undef ADR 1095 #undef LANG 1096 #undef OBJ 1097 #undef CLS 1098 #undef FLD 1099 #undef THR 1100 #undef DC_Args 1101 #undef DAC_Args 1102 1103 #undef DECLARE_GETPUTOOP 1104 1105 1106 // This function is exported, used by NativeLookup. 1107 // The Unsafe_xxx functions above are called only from the interpreter. 1108 // The optimizer looks at names and signatures to recognize 1109 // individual functions. 1110 1111 JVM_ENTRY(void, JVM_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) { 1112 ThreadToNativeFromVM ttnfv(thread); 1113 1114 int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod)); 1115 guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives"); 1116 } JVM_END