1 /*
   2  * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/vmSymbols.hpp"
  27 #include "utilities/macros.hpp"
  28 #if INCLUDE_ALL_GCS
  29 #include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
  30 #endif // INCLUDE_ALL_GCS
  31 #include "memory/allocation.inline.hpp"
  32 #include "prims/jni.h"
  33 #include "prims/jvm.h"
  34 #include "runtime/globals.hpp"
  35 #include "runtime/interfaceSupport.hpp"
  36 #include "runtime/reflection.hpp"
  37 #include "runtime/synchronizer.hpp"
  38 #include "services/threadService.hpp"
  39 #include "utilities/copy.hpp"
  40 #include "utilities/dtrace.hpp"
  41 
  42 /*
  43  *      Implementation of class sun.misc.Unsafe
  44  */
  45 
  46 #ifndef USDT2
  47 HS_DTRACE_PROBE_DECL3(hotspot, thread__park__begin, uintptr_t, int, long long);
  48 HS_DTRACE_PROBE_DECL1(hotspot, thread__park__end, uintptr_t);
  49 HS_DTRACE_PROBE_DECL1(hotspot, thread__unpark, uintptr_t);
  50 #endif /* !USDT2 */
  51 
  52 #define MAX_OBJECT_SIZE \
  53   ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
  54     + ((julong)max_jint * sizeof(double)) )
  55 
  56 
  57 #define UNSAFE_ENTRY(result_type, header) \
  58   JVM_ENTRY(result_type, header)
  59 
  60 // Can't use UNSAFE_LEAF because it has the signature of a straight
  61 // call into the runtime (just like JVM_LEAF, funny that) but it's
  62 // called like a Java Native and thus the wrapper built for it passes
  63 // arguments like a JNI call.  It expects those arguments to be popped
  64 // from the stack on Intel like all good JNI args are, and adjusts the
  65 // stack according.  Since the JVM_LEAF call expects no extra
  66 // arguments the stack isn't popped in the C code, is pushed by the
  67 // wrapper and we get sick.
  68 //#define UNSAFE_LEAF(result_type, header) \
  69 //  JVM_LEAF(result_type, header)
  70 
  71 #define UNSAFE_END JVM_END
  72 
  73 #define UnsafeWrapper(arg) /*nothing, for the present*/
  74 
  75 
  76 inline void* addr_from_java(jlong addr) {
  77   // This assert fails in a variety of ways on 32-bit systems.
  78   // It is impossible to predict whether native code that converts
  79   // pointers to longs will sign-extend or zero-extend the addresses.
  80   //assert(addr == (uintptr_t)addr, "must not be odd high bits");
  81   return (void*)(uintptr_t)addr;
  82 }
  83 
  84 inline jlong addr_to_java(void* p) {
  85   assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
  86   return (uintptr_t)p;
  87 }
  88 
  89 
  90 // Note: The VM's obj_field and related accessors use byte-scaled
  91 // ("unscaled") offsets, just as the unsafe methods do.
  92 
  93 // However, the method Unsafe.fieldOffset explicitly declines to
  94 // guarantee this.  The field offset values manipulated by the Java user
  95 // through the Unsafe API are opaque cookies that just happen to be byte
  96 // offsets.  We represent this state of affairs by passing the cookies
  97 // through conversion functions when going between the VM and the Unsafe API.
  98 // The conversion functions just happen to be no-ops at present.
  99 
 100 inline jlong field_offset_to_byte_offset(jlong field_offset) {
 101   return field_offset;
 102 }
 103 
 104 inline jlong field_offset_from_byte_offset(jlong byte_offset) {
 105   return byte_offset;
 106 }
 107 
 108 inline jint invocation_key_from_method_slot(jint slot) {
 109   return slot;
 110 }
 111 
 112 inline jint invocation_key_to_method_slot(jint key) {
 113   return key;
 114 }
 115 
 116 inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
 117   jlong byte_offset = field_offset_to_byte_offset(field_offset);
 118   // Don't allow unsafe to be used to read or write the header word of oops
 119   assert(p == NULL || field_offset >= oopDesc::header_size(), "offset must be outside of header");
 120 #ifdef ASSERT
 121   if (p != NULL) {
 122     assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
 123     if (byte_offset == (jint)byte_offset) {
 124       void* ptr_plus_disp = (address)p + byte_offset;
 125       assert((void*)p->obj_field_addr<oop>((jint)byte_offset) == ptr_plus_disp,
 126              "raw [ptr+disp] must be consistent with oop::field_base");
 127     }
 128     jlong p_size = HeapWordSize * (jlong)(p->size());
 129     assert(byte_offset < p_size, err_msg("Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, byte_offset, p_size));
 130   }
 131 #endif
 132   if (sizeof(char*) == sizeof(jint))    // (this constant folds!)
 133     return (address)p + (jint) byte_offset;
 134   else
 135     return (address)p +        byte_offset;
 136 }
 137 
 138 // Externally callable versions:
 139 // (Use these in compiler intrinsics which emulate unsafe primitives.)
 140 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
 141   return field_offset;
 142 }
 143 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
 144   return byte_offset;
 145 }
 146 jint Unsafe_invocation_key_from_method_slot(jint slot) {
 147   return invocation_key_from_method_slot(slot);
 148 }
 149 jint Unsafe_invocation_key_to_method_slot(jint key) {
 150   return invocation_key_to_method_slot(key);
 151 }
 152 
 153 
 154 ///// Data in the Java heap.
 155 
 156 #define GET_FIELD(obj, offset, type_name, v) \
 157   oop p = JNIHandles::resolve(obj); \
 158   type_name v = *(type_name*)index_oop_from_field_offset_long(p, offset)
 159 
 160 #define SET_FIELD(obj, offset, type_name, x) \
 161   oop p = JNIHandles::resolve(obj); \
 162   *(type_name*)index_oop_from_field_offset_long(p, offset) = x
 163 
 164 #define GET_FIELD_VOLATILE(obj, offset, type_name, v) \
 165   oop p = JNIHandles::resolve(obj); \
 166   volatile type_name v = OrderAccess::load_acquire((volatile type_name*)index_oop_from_field_offset_long(p, offset));
 167 
 168 #define SET_FIELD_VOLATILE(obj, offset, type_name, x) \
 169   oop p = JNIHandles::resolve(obj); \
 170   OrderAccess::release_store_fence((volatile type_name*)index_oop_from_field_offset_long(p, offset), x);
 171 
 172 // Macros for oops that check UseCompressedOops
 173 
 174 #define GET_OOP_FIELD(obj, offset, v) \
 175   oop p = JNIHandles::resolve(obj);   \
 176   oop v;                              \
 177   if (UseCompressedOops) {            \
 178     narrowOop n = *(narrowOop*)index_oop_from_field_offset_long(p, offset); \
 179     v = oopDesc::decode_heap_oop(n);                                \
 180   } else {                            \
 181     v = *(oop*)index_oop_from_field_offset_long(p, offset);                 \
 182   }
 183 
 184 
 185 // Get/SetObject must be special-cased, since it works with handles.
 186 
 187 // The xxx140 variants for backward compatibility do not allow a full-width offset.
 188 UNSAFE_ENTRY(jobject, Unsafe_GetObject140(JNIEnv *env, jobject unsafe, jobject obj, jint offset))
 189   UnsafeWrapper("Unsafe_GetObject");
 190   if (obj == NULL)  THROW_0(vmSymbols::java_lang_NullPointerException());
 191   GET_OOP_FIELD(obj, offset, v)
 192   jobject ret = JNIHandles::make_local(env, v);
 193 #if INCLUDE_ALL_GCS
 194   // We could be accessing the referent field in a reference
 195   // object. If G1 is enabled then we need to register a non-null
 196   // referent with the SATB barrier.
 197   if (UseG1GC) {
 198     bool needs_barrier = false;
 199 
 200     if (ret != NULL) {
 201       if (offset == java_lang_ref_Reference::referent_offset) {
 202         oop o = JNIHandles::resolve_non_null(obj);
 203         Klass* k = o->klass();
 204         if (InstanceKlass::cast(k)->reference_type() != REF_NONE) {
 205           assert(InstanceKlass::cast(k)->is_subclass_of(SystemDictionary::Reference_klass()), "sanity");
 206           needs_barrier = true;
 207         }
 208       }
 209     }
 210 
 211     if (needs_barrier) {
 212       oop referent = JNIHandles::resolve(ret);
 213       G1SATBCardTableModRefBS::enqueue(referent);
 214     }
 215   }
 216 #endif // INCLUDE_ALL_GCS
 217   return ret;
 218 UNSAFE_END
 219 
 220 UNSAFE_ENTRY(void, Unsafe_SetObject140(JNIEnv *env, jobject unsafe, jobject obj, jint offset, jobject x_h))
 221   UnsafeWrapper("Unsafe_SetObject");
 222   if (obj == NULL)  THROW(vmSymbols::java_lang_NullPointerException());
 223   oop x = JNIHandles::resolve(x_h);
 224   //SET_FIELD(obj, offset, oop, x);
 225   oop p = JNIHandles::resolve(obj);
 226   if (UseCompressedOops) {
 227     if (x != NULL) {
 228       // If there is a heap base pointer, we are obliged to emit a store barrier.
 229       oop_store((narrowOop*)index_oop_from_field_offset_long(p, offset), x);
 230     } else {
 231       narrowOop n = oopDesc::encode_heap_oop_not_null(x);
 232       *(narrowOop*)index_oop_from_field_offset_long(p, offset) = n;
 233     }
 234   } else {
 235     if (x != NULL) {
 236       // If there is a heap base pointer, we are obliged to emit a store barrier.
 237       oop_store((oop*)index_oop_from_field_offset_long(p, offset), x);
 238     } else {
 239       *(oop*)index_oop_from_field_offset_long(p, offset) = x;
 240     }
 241   }
 242 UNSAFE_END
 243 
 244 // The normal variants allow a null base pointer with an arbitrary address.
 245 // But if the base pointer is non-null, the offset should make some sense.
 246 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
 247 UNSAFE_ENTRY(jobject, Unsafe_GetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset))
 248   UnsafeWrapper("Unsafe_GetObject");
 249   GET_OOP_FIELD(obj, offset, v)
 250   jobject ret = JNIHandles::make_local(env, v);
 251 #if INCLUDE_ALL_GCS
 252   // We could be accessing the referent field in a reference
 253   // object. If G1 is enabled then we need to register non-null
 254   // referent with the SATB barrier.
 255   if (UseG1GC) {
 256     bool needs_barrier = false;
 257 
 258     if (ret != NULL) {
 259       if (offset == java_lang_ref_Reference::referent_offset && obj != NULL) {
 260         oop o = JNIHandles::resolve(obj);
 261         Klass* k = o->klass();
 262         if (InstanceKlass::cast(k)->reference_type() != REF_NONE) {
 263           assert(InstanceKlass::cast(k)->is_subclass_of(SystemDictionary::Reference_klass()), "sanity");
 264           needs_barrier = true;
 265         }
 266       }
 267     }
 268 
 269     if (needs_barrier) {
 270       oop referent = JNIHandles::resolve(ret);
 271       G1SATBCardTableModRefBS::enqueue(referent);
 272     }
 273   }
 274 #endif // INCLUDE_ALL_GCS
 275   return ret;
 276 UNSAFE_END
 277 
 278 UNSAFE_ENTRY(void, Unsafe_SetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h))
 279   UnsafeWrapper("Unsafe_SetObject");
 280   oop x = JNIHandles::resolve(x_h);
 281   oop p = JNIHandles::resolve(obj);
 282   if (UseCompressedOops) {
 283     oop_store((narrowOop*)index_oop_from_field_offset_long(p, offset), x);
 284   } else {
 285     oop_store((oop*)index_oop_from_field_offset_long(p, offset), x);
 286   }
 287 UNSAFE_END
 288 
 289 UNSAFE_ENTRY(jobject, Unsafe_GetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset))
 290   UnsafeWrapper("Unsafe_GetObjectVolatile");
 291   oop p = JNIHandles::resolve(obj);
 292   void* addr = index_oop_from_field_offset_long(p, offset);
 293   volatile oop v;
 294   if (UseCompressedOops) {
 295     volatile narrowOop n = *(volatile narrowOop*) addr;
 296     v = oopDesc::decode_heap_oop(n);
 297   } else {
 298     v = *(volatile oop*) addr;
 299   }
 300   OrderAccess::acquire();
 301   return JNIHandles::make_local(env, v);
 302 UNSAFE_END
 303 
 304 UNSAFE_ENTRY(void, Unsafe_SetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h))
 305   UnsafeWrapper("Unsafe_SetObjectVolatile");
 306   oop x = JNIHandles::resolve(x_h);
 307   oop p = JNIHandles::resolve(obj);
 308   void* addr = index_oop_from_field_offset_long(p, offset);
 309   OrderAccess::release();
 310   if (UseCompressedOops) {
 311     oop_store((narrowOop*)addr, x);
 312   } else {
 313     oop_store((oop*)addr, x);
 314   }
 315   OrderAccess::fence();
 316 UNSAFE_END
 317 
 318 #ifndef SUPPORTS_NATIVE_CX8
 319 // Keep old code for platforms which may not have atomic jlong (8 bytes) instructions
 320 
 321 // Volatile long versions must use locks if !VM_Version::supports_cx8().
 322 // support_cx8 is a surrogate for 'supports atomic long memory ops'.
 323 
 324 UNSAFE_ENTRY(jlong, Unsafe_GetLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset))
 325   UnsafeWrapper("Unsafe_GetLongVolatile");
 326   {
 327     if (VM_Version::supports_cx8()) {
 328       GET_FIELD_VOLATILE(obj, offset, jlong, v);
 329       return v;
 330     }
 331     else {
 332       Handle p (THREAD, JNIHandles::resolve(obj));
 333       jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
 334       ObjectLocker ol(p, THREAD);
 335       jlong value = *addr;
 336       return value;
 337     }
 338   }
 339 UNSAFE_END
 340 
 341 UNSAFE_ENTRY(void, Unsafe_SetLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong x))
 342   UnsafeWrapper("Unsafe_SetLongVolatile");
 343   {
 344     if (VM_Version::supports_cx8()) {
 345       SET_FIELD_VOLATILE(obj, offset, jlong, x);
 346     }
 347     else {
 348       Handle p (THREAD, JNIHandles::resolve(obj));
 349       jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
 350       ObjectLocker ol(p, THREAD);
 351       *addr = x;
 352     }
 353   }
 354 UNSAFE_END
 355 
 356 #endif // not SUPPORTS_NATIVE_CX8
 357 
 358 #define DEFINE_GETSETOOP(jboolean, Boolean) \
 359  \
 360 UNSAFE_ENTRY(jboolean, Unsafe_Get##Boolean##140(JNIEnv *env, jobject unsafe, jobject obj, jint offset)) \
 361   UnsafeWrapper("Unsafe_Get"#Boolean); \
 362   if (obj == NULL)  THROW_0(vmSymbols::java_lang_NullPointerException()); \
 363   GET_FIELD(obj, offset, jboolean, v); \
 364   return v; \
 365 UNSAFE_END \
 366  \
 367 UNSAFE_ENTRY(void, Unsafe_Set##Boolean##140(JNIEnv *env, jobject unsafe, jobject obj, jint offset, jboolean x)) \
 368   UnsafeWrapper("Unsafe_Set"#Boolean); \
 369   if (obj == NULL)  THROW(vmSymbols::java_lang_NullPointerException()); \
 370   SET_FIELD(obj, offset, jboolean, x); \
 371 UNSAFE_END \
 372  \
 373 UNSAFE_ENTRY(jboolean, Unsafe_Get##Boolean(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) \
 374   UnsafeWrapper("Unsafe_Get"#Boolean); \
 375   GET_FIELD(obj, offset, jboolean, v); \
 376   return v; \
 377 UNSAFE_END \
 378  \
 379 UNSAFE_ENTRY(void, Unsafe_Set##Boolean(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jboolean x)) \
 380   UnsafeWrapper("Unsafe_Set"#Boolean); \
 381   SET_FIELD(obj, offset, jboolean, x); \
 382 UNSAFE_END \
 383  \
 384 // END DEFINE_GETSETOOP.
 385 
 386 DEFINE_GETSETOOP(jboolean, Boolean)
 387 DEFINE_GETSETOOP(jbyte, Byte)
 388 DEFINE_GETSETOOP(jshort, Short);
 389 DEFINE_GETSETOOP(jchar, Char);
 390 DEFINE_GETSETOOP(jint, Int);
 391 DEFINE_GETSETOOP(jlong, Long);
 392 DEFINE_GETSETOOP(jfloat, Float);
 393 DEFINE_GETSETOOP(jdouble, Double);
 394 
 395 #undef DEFINE_GETSETOOP
 396 
 397 #define DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean) \
 398  \
 399 UNSAFE_ENTRY(jboolean, Unsafe_Get##Boolean##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) \
 400   UnsafeWrapper("Unsafe_Get"#Boolean); \
 401   GET_FIELD_VOLATILE(obj, offset, jboolean, v); \
 402   return v; \
 403 UNSAFE_END \
 404  \
 405 UNSAFE_ENTRY(void, Unsafe_Set##Boolean##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jboolean x)) \
 406   UnsafeWrapper("Unsafe_Set"#Boolean); \
 407   SET_FIELD_VOLATILE(obj, offset, jboolean, x); \
 408 UNSAFE_END \
 409  \
 410 // END DEFINE_GETSETOOP_VOLATILE.
 411 
 412 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
 413 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
 414 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
 415 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
 416 DEFINE_GETSETOOP_VOLATILE(jint, Int);
 417 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
 418 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
 419 
 420 #ifdef SUPPORTS_NATIVE_CX8
 421 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
 422 #endif
 423 
 424 #undef DEFINE_GETSETOOP_VOLATILE
 425 
 426 // The non-intrinsified versions of setOrdered just use setVolatile
 427 
 428 UNSAFE_ENTRY(void, Unsafe_SetOrderedInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint x))
 429   UnsafeWrapper("Unsafe_SetOrderedInt");
 430   SET_FIELD_VOLATILE(obj, offset, jint, x);
 431 UNSAFE_END
 432 
 433 UNSAFE_ENTRY(void, Unsafe_SetOrderedObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h))
 434   UnsafeWrapper("Unsafe_SetOrderedObject");
 435   oop x = JNIHandles::resolve(x_h);
 436   oop p = JNIHandles::resolve(obj);
 437   void* addr = index_oop_from_field_offset_long(p, offset);
 438   OrderAccess::release();
 439   if (UseCompressedOops) {
 440     oop_store((narrowOop*)addr, x);
 441   } else {
 442     oop_store((oop*)addr, x);
 443   }
 444   OrderAccess::fence();
 445 UNSAFE_END
 446 
 447 UNSAFE_ENTRY(void, Unsafe_SetOrderedLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong x))
 448   UnsafeWrapper("Unsafe_SetOrderedLong");
 449 #ifdef SUPPORTS_NATIVE_CX8
 450   SET_FIELD_VOLATILE(obj, offset, jlong, x);
 451 #else
 452   // Keep old code for platforms which may not have atomic long (8 bytes) instructions
 453   {
 454     if (VM_Version::supports_cx8()) {
 455       SET_FIELD_VOLATILE(obj, offset, jlong, x);
 456     }
 457     else {
 458       Handle p (THREAD, JNIHandles::resolve(obj));
 459       jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
 460       ObjectLocker ol(p, THREAD);
 461       *addr = x;
 462     }
 463   }
 464 #endif
 465 UNSAFE_END
 466 
 467 UNSAFE_ENTRY(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe))
 468   UnsafeWrapper("Unsafe_LoadFence");
 469   OrderAccess::acquire();
 470 UNSAFE_END
 471 
 472 UNSAFE_ENTRY(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe))
 473   UnsafeWrapper("Unsafe_StoreFence");
 474   OrderAccess::release();
 475 UNSAFE_END
 476 
 477 UNSAFE_ENTRY(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe))
 478   UnsafeWrapper("Unsafe_FullFence");
 479   OrderAccess::fence();
 480 UNSAFE_END
 481 
 482 ////// Data in the C heap.
 483 
 484 // Note:  These do not throw NullPointerException for bad pointers.
 485 // They just crash.  Only a oop base pointer can generate a NullPointerException.
 486 //
 487 #define DEFINE_GETSETNATIVE(java_type, Type, native_type) \
 488  \
 489 UNSAFE_ENTRY(java_type, Unsafe_GetNative##Type(JNIEnv *env, jobject unsafe, jlong addr)) \
 490   UnsafeWrapper("Unsafe_GetNative"#Type); \
 491   void* p = addr_from_java(addr); \
 492   JavaThread* t = JavaThread::current(); \
 493   t->set_doing_unsafe_access(true); \
 494   java_type x = *(volatile native_type*)p; \
 495   t->set_doing_unsafe_access(false); \
 496   return x; \
 497 UNSAFE_END \
 498  \
 499 UNSAFE_ENTRY(void, Unsafe_SetNative##Type(JNIEnv *env, jobject unsafe, jlong addr, java_type x)) \
 500   UnsafeWrapper("Unsafe_SetNative"#Type); \
 501   JavaThread* t = JavaThread::current(); \
 502   t->set_doing_unsafe_access(true); \
 503   void* p = addr_from_java(addr); \
 504   *(volatile native_type*)p = x; \
 505   t->set_doing_unsafe_access(false); \
 506 UNSAFE_END \
 507  \
 508 // END DEFINE_GETSETNATIVE.
 509 
 510 DEFINE_GETSETNATIVE(jbyte, Byte, signed char)
 511 DEFINE_GETSETNATIVE(jshort, Short, signed short);
 512 DEFINE_GETSETNATIVE(jchar, Char, unsigned short);
 513 DEFINE_GETSETNATIVE(jint, Int, jint);
 514 // no long -- handled specially
 515 DEFINE_GETSETNATIVE(jfloat, Float, float);
 516 DEFINE_GETSETNATIVE(jdouble, Double, double);
 517 
 518 #undef DEFINE_GETSETNATIVE
 519 
 520 UNSAFE_ENTRY(jlong, Unsafe_GetNativeLong(JNIEnv *env, jobject unsafe, jlong addr))
 521   UnsafeWrapper("Unsafe_GetNativeLong");
 522   JavaThread* t = JavaThread::current();
 523   // We do it this way to avoid problems with access to heap using 64
 524   // bit loads, as jlong in heap could be not 64-bit aligned, and on
 525   // some CPUs (SPARC) it leads to SIGBUS.
 526   t->set_doing_unsafe_access(true);
 527   void* p = addr_from_java(addr);
 528   jlong x;
 529   if (((intptr_t)p & 7) == 0) {
 530     // jlong is aligned, do a volatile access
 531     x = *(volatile jlong*)p;
 532   } else {
 533     jlong_accessor acc;
 534     acc.words[0] = ((volatile jint*)p)[0];
 535     acc.words[1] = ((volatile jint*)p)[1];
 536     x = acc.long_value;
 537   }
 538   t->set_doing_unsafe_access(false);
 539   return x;
 540 UNSAFE_END
 541 
 542 UNSAFE_ENTRY(void, Unsafe_SetNativeLong(JNIEnv *env, jobject unsafe, jlong addr, jlong x))
 543   UnsafeWrapper("Unsafe_SetNativeLong");
 544   JavaThread* t = JavaThread::current();
 545   // see comment for Unsafe_GetNativeLong
 546   t->set_doing_unsafe_access(true);
 547   void* p = addr_from_java(addr);
 548   if (((intptr_t)p & 7) == 0) {
 549     // jlong is aligned, do a volatile access
 550     *(volatile jlong*)p = x;
 551   } else {
 552     jlong_accessor acc;
 553     acc.long_value = x;
 554     ((volatile jint*)p)[0] = acc.words[0];
 555     ((volatile jint*)p)[1] = acc.words[1];
 556   }
 557   t->set_doing_unsafe_access(false);
 558 UNSAFE_END
 559 
 560 
 561 UNSAFE_ENTRY(jlong, Unsafe_GetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr))
 562   UnsafeWrapper("Unsafe_GetNativeAddress");
 563   void* p = addr_from_java(addr);
 564   return addr_to_java(*(void**)p);
 565 UNSAFE_END
 566 
 567 UNSAFE_ENTRY(void, Unsafe_SetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr, jlong x))
 568   UnsafeWrapper("Unsafe_SetNativeAddress");
 569   void* p = addr_from_java(addr);
 570   *(void**)p = addr_from_java(x);
 571 UNSAFE_END
 572 
 573 
 574 ////// Allocation requests
 575 
 576 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls))
 577   UnsafeWrapper("Unsafe_AllocateInstance");
 578   {
 579     ThreadToNativeFromVM ttnfv(thread);
 580     return env->AllocObject(cls);
 581   }
 582 UNSAFE_END
 583 
 584 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory(JNIEnv *env, jobject unsafe, jlong size))
 585   UnsafeWrapper("Unsafe_AllocateMemory");
 586   size_t sz = (size_t)size;
 587   if (sz != (julong)size || size < 0) {
 588     THROW_0(vmSymbols::java_lang_IllegalArgumentException());
 589   }
 590   if (sz == 0) {
 591     return 0;
 592   }
 593   sz = round_to(sz, HeapWordSize);
 594   void* x = os::malloc(sz, mtInternal);
 595   if (x == NULL) {
 596     THROW_0(vmSymbols::java_lang_OutOfMemoryError());
 597   }
 598   //Copy::fill_to_words((HeapWord*)x, sz / HeapWordSize);
 599   return addr_to_java(x);
 600 UNSAFE_END
 601 
 602 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory(JNIEnv *env, jobject unsafe, jlong addr, jlong size))
 603   UnsafeWrapper("Unsafe_ReallocateMemory");
 604   void* p = addr_from_java(addr);
 605   size_t sz = (size_t)size;
 606   if (sz != (julong)size || size < 0) {
 607     THROW_0(vmSymbols::java_lang_IllegalArgumentException());
 608   }
 609   if (sz == 0) {
 610     os::free(p);
 611     return 0;
 612   }
 613   sz = round_to(sz, HeapWordSize);
 614   void* x = (p == NULL) ? os::malloc(sz, mtInternal) : os::realloc(p, sz, mtInternal);
 615   if (x == NULL) {
 616     THROW_0(vmSymbols::java_lang_OutOfMemoryError());
 617   }
 618   return addr_to_java(x);
 619 UNSAFE_END
 620 
 621 UNSAFE_ENTRY(void, Unsafe_FreeMemory(JNIEnv *env, jobject unsafe, jlong addr))
 622   UnsafeWrapper("Unsafe_FreeMemory");
 623   void* p = addr_from_java(addr);
 624   if (p == NULL) {
 625     return;
 626   }
 627   os::free(p);
 628 UNSAFE_END
 629 
 630 UNSAFE_ENTRY(void, Unsafe_SetMemory(JNIEnv *env, jobject unsafe, jlong addr, jlong size, jbyte value))
 631   UnsafeWrapper("Unsafe_SetMemory");
 632   size_t sz = (size_t)size;
 633   if (sz != (julong)size || size < 0) {
 634     THROW(vmSymbols::java_lang_IllegalArgumentException());
 635   }
 636   char* p = (char*) addr_from_java(addr);
 637   Copy::fill_to_memory_atomic(p, sz, value);
 638 UNSAFE_END
 639 
 640 UNSAFE_ENTRY(void, Unsafe_SetMemory2(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value))
 641   UnsafeWrapper("Unsafe_SetMemory");
 642   size_t sz = (size_t)size;
 643   if (sz != (julong)size || size < 0) {
 644     THROW(vmSymbols::java_lang_IllegalArgumentException());
 645   }
 646   oop base = JNIHandles::resolve(obj);
 647   void* p = index_oop_from_field_offset_long(base, offset);
 648   Copy::fill_to_memory_atomic(p, sz, value);
 649 UNSAFE_END
 650 
 651 UNSAFE_ENTRY(void, Unsafe_CopyMemory(JNIEnv *env, jobject unsafe, jlong srcAddr, jlong dstAddr, jlong size))
 652   UnsafeWrapper("Unsafe_CopyMemory");
 653   if (size == 0) {
 654     return;
 655   }
 656   size_t sz = (size_t)size;
 657   if (sz != (julong)size || size < 0) {
 658     THROW(vmSymbols::java_lang_IllegalArgumentException());
 659   }
 660   void* src = addr_from_java(srcAddr);
 661   void* dst = addr_from_java(dstAddr);
 662   Copy::conjoint_memory_atomic(src, dst, sz);
 663 UNSAFE_END
 664 
 665 UNSAFE_ENTRY(void, Unsafe_CopyMemory2(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size))
 666   UnsafeWrapper("Unsafe_CopyMemory");
 667   if (size == 0) {
 668     return;
 669   }
 670   size_t sz = (size_t)size;
 671   if (sz != (julong)size || size < 0) {
 672     THROW(vmSymbols::java_lang_IllegalArgumentException());
 673   }
 674   oop srcp = JNIHandles::resolve(srcObj);
 675   oop dstp = JNIHandles::resolve(dstObj);
 676   if (dstp != NULL && !dstp->is_typeArray()) {
 677     // NYI:  This works only for non-oop arrays at present.
 678     // Generalizing it would be reasonable, but requires card marking.
 679     // Also, autoboxing a Long from 0L in copyMemory(x,y, 0L,z, n) would be bad.
 680     THROW(vmSymbols::java_lang_IllegalArgumentException());
 681   }
 682   void* src = index_oop_from_field_offset_long(srcp, srcOffset);
 683   void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
 684   Copy::conjoint_memory_atomic(src, dst, sz);
 685 UNSAFE_END
 686 
 687 
 688 ////// Random queries
 689 
 690 // See comment at file start about UNSAFE_LEAF
 691 //UNSAFE_LEAF(jint, Unsafe_AddressSize())
 692 UNSAFE_ENTRY(jint, Unsafe_AddressSize(JNIEnv *env, jobject unsafe))
 693   UnsafeWrapper("Unsafe_AddressSize");
 694   return sizeof(void*);
 695 UNSAFE_END
 696 
 697 // See comment at file start about UNSAFE_LEAF
 698 //UNSAFE_LEAF(jint, Unsafe_PageSize())
 699 UNSAFE_ENTRY(jint, Unsafe_PageSize(JNIEnv *env, jobject unsafe))
 700   UnsafeWrapper("Unsafe_PageSize");
 701   return os::vm_page_size();
 702 UNSAFE_END
 703 
 704 jint find_field_offset(jobject field, int must_be_static, TRAPS) {
 705   if (field == NULL) {
 706     THROW_0(vmSymbols::java_lang_NullPointerException());
 707   }
 708 
 709   oop reflected   = JNIHandles::resolve_non_null(field);
 710   oop mirror      = java_lang_reflect_Field::clazz(reflected);
 711   Klass* k      = java_lang_Class::as_Klass(mirror);
 712   int slot        = java_lang_reflect_Field::slot(reflected);
 713   int modifiers   = java_lang_reflect_Field::modifiers(reflected);
 714 
 715   if (must_be_static >= 0) {
 716     int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
 717     if (must_be_static != really_is_static) {
 718       THROW_0(vmSymbols::java_lang_IllegalArgumentException());
 719     }
 720   }
 721 
 722   int offset = InstanceKlass::cast(k)->field_offset(slot);
 723   return field_offset_from_byte_offset(offset);
 724 }
 725 
 726 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset(JNIEnv *env, jobject unsafe, jobject field))
 727   UnsafeWrapper("Unsafe_ObjectFieldOffset");
 728   return find_field_offset(field, 0, THREAD);
 729 UNSAFE_END
 730 
 731 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset(JNIEnv *env, jobject unsafe, jobject field))
 732   UnsafeWrapper("Unsafe_StaticFieldOffset");
 733   return find_field_offset(field, 1, THREAD);
 734 UNSAFE_END
 735 
 736 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBaseFromField(JNIEnv *env, jobject unsafe, jobject field))
 737   UnsafeWrapper("Unsafe_StaticFieldBase");
 738   // Note:  In this VM implementation, a field address is always a short
 739   // offset from the base of a a klass metaobject.  Thus, the full dynamic
 740   // range of the return type is never used.  However, some implementations
 741   // might put the static field inside an array shared by many classes,
 742   // or even at a fixed address, in which case the address could be quite
 743   // large.  In that last case, this function would return NULL, since
 744   // the address would operate alone, without any base pointer.
 745 
 746   if (field == NULL)  THROW_0(vmSymbols::java_lang_NullPointerException());
 747 
 748   oop reflected   = JNIHandles::resolve_non_null(field);
 749   oop mirror      = java_lang_reflect_Field::clazz(reflected);
 750   int modifiers   = java_lang_reflect_Field::modifiers(reflected);
 751 
 752   if ((modifiers & JVM_ACC_STATIC) == 0) {
 753     THROW_0(vmSymbols::java_lang_IllegalArgumentException());
 754   }
 755 
 756   return JNIHandles::make_local(env, mirror);
 757 UNSAFE_END
 758 
 759 //@deprecated
 760 UNSAFE_ENTRY(jint, Unsafe_FieldOffset(JNIEnv *env, jobject unsafe, jobject field))
 761   UnsafeWrapper("Unsafe_FieldOffset");
 762   // tries (but fails) to be polymorphic between static and non-static:
 763   jlong offset = find_field_offset(field, -1, THREAD);
 764   guarantee(offset == (jint)offset, "offset fits in 32 bits");
 765   return (jint)offset;
 766 UNSAFE_END
 767 
 768 //@deprecated
 769 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBaseFromClass(JNIEnv *env, jobject unsafe, jobject clazz))
 770   UnsafeWrapper("Unsafe_StaticFieldBase");
 771   if (clazz == NULL) {
 772     THROW_0(vmSymbols::java_lang_NullPointerException());
 773   }
 774   return JNIHandles::make_local(env, JNIHandles::resolve_non_null(clazz));
 775 UNSAFE_END
 776 
 777 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized(JNIEnv *env, jobject unsafe, jobject clazz)) {
 778   UnsafeWrapper("Unsafe_EnsureClassInitialized");
 779   if (clazz == NULL) {
 780     THROW(vmSymbols::java_lang_NullPointerException());
 781   }
 782   oop mirror = JNIHandles::resolve_non_null(clazz);
 783 
 784   Klass* klass = java_lang_Class::as_Klass(mirror);
 785   if (klass != NULL && klass->should_be_initialized()) {
 786     InstanceKlass* k = InstanceKlass::cast(klass);
 787     k->initialize(CHECK);
 788   }
 789 }
 790 UNSAFE_END
 791 
 792 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized(JNIEnv *env, jobject unsafe, jobject clazz)) {
 793   UnsafeWrapper("Unsafe_ShouldBeInitialized");
 794   if (clazz == NULL) {
 795     THROW_(vmSymbols::java_lang_NullPointerException(), false);
 796   }
 797   oop mirror = JNIHandles::resolve_non_null(clazz);
 798   Klass* klass = java_lang_Class::as_Klass(mirror);
 799   if (klass != NULL && klass->should_be_initialized()) {
 800     return true;
 801   }
 802   return false;
 803 }
 804 UNSAFE_END
 805 
 806 static void getBaseAndScale(int& base, int& scale, jclass acls, TRAPS) {
 807   if (acls == NULL) {
 808     THROW(vmSymbols::java_lang_NullPointerException());
 809   }
 810   oop      mirror = JNIHandles::resolve_non_null(acls);
 811   Klass* k      = java_lang_Class::as_Klass(mirror);
 812   if (k == NULL || !k->oop_is_array()) {
 813     THROW(vmSymbols::java_lang_InvalidClassException());
 814   } else if (k->oop_is_objArray()) {
 815     base  = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
 816     scale = heapOopSize;
 817   } else if (k->oop_is_typeArray()) {
 818     TypeArrayKlass* tak = TypeArrayKlass::cast(k);
 819     base  = tak->array_header_in_bytes();
 820     assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
 821     scale = (1 << tak->log2_element_size());
 822   } else {
 823     ShouldNotReachHere();
 824   }
 825 }
 826 
 827 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset(JNIEnv *env, jobject unsafe, jclass acls))
 828   UnsafeWrapper("Unsafe_ArrayBaseOffset");
 829   int base, scale;
 830   getBaseAndScale(base, scale, acls, CHECK_0);
 831   return field_offset_from_byte_offset(base);
 832 UNSAFE_END
 833 
 834 
 835 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale(JNIEnv *env, jobject unsafe, jclass acls))
 836   UnsafeWrapper("Unsafe_ArrayIndexScale");
 837   int base, scale;
 838   getBaseAndScale(base, scale, acls, CHECK_0);
 839   // This VM packs both fields and array elements down to the byte.
 840   // But watch out:  If this changes, so that array references for
 841   // a given primitive type (say, T_BOOLEAN) use different memory units
 842   // than fields, this method MUST return zero for such arrays.
 843   // For example, the VM used to store sub-word sized fields in full
 844   // words in the object layout, so that accessors like getByte(Object,int)
 845   // did not really do what one might expect for arrays.  Therefore,
 846   // this function used to report a zero scale factor, so that the user
 847   // would know not to attempt to access sub-word array elements.
 848   // // Code for unpacked fields:
 849   // if (scale < wordSize)  return 0;
 850 
 851   // The following allows for a pretty general fieldOffset cookie scheme,
 852   // but requires it to be linear in byte offset.
 853   return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
 854 UNSAFE_END
 855 
 856 
 857 static inline void throw_new(JNIEnv *env, const char *ename) {
 858   char buf[100];
 859   strcpy(buf, "java/lang/");
 860   strcat(buf, ename);
 861   jclass cls = env->FindClass(buf);
 862   char* msg = NULL;
 863   env->ThrowNew(cls, msg);
 864 }
 865 
 866 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
 867   {
 868     // Code lifted from JDK 1.3 ClassLoader.c
 869 
 870     jbyte *body;
 871     char *utfName;
 872     jclass result = 0;
 873     char buf[128];
 874 
 875     if (UsePerfData) {
 876       ClassLoader::unsafe_defineClassCallCounter()->inc();
 877     }
 878 
 879     if (data == NULL) {
 880         throw_new(env, "NullPointerException");
 881         return 0;
 882     }
 883 
 884     /* Work around 4153825. malloc crashes on Solaris when passed a
 885      * negative size.
 886      */
 887     if (length < 0) {
 888         throw_new(env, "ArrayIndexOutOfBoundsException");
 889         return 0;
 890     }
 891 
 892     body = NEW_C_HEAP_ARRAY(jbyte, length, mtInternal);
 893 
 894     if (body == 0) {
 895         throw_new(env, "OutOfMemoryError");
 896         return 0;
 897     }
 898 
 899     env->GetByteArrayRegion(data, offset, length, body);
 900 
 901     if (env->ExceptionOccurred())
 902         goto free_body;
 903 
 904     if (name != NULL) {
 905         uint len = env->GetStringUTFLength(name);
 906         int unicode_len = env->GetStringLength(name);
 907         if (len >= sizeof(buf)) {
 908             utfName = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
 909             if (utfName == NULL) {
 910                 throw_new(env, "OutOfMemoryError");
 911                 goto free_body;
 912             }
 913         } else {
 914             utfName = buf;
 915         }
 916         env->GetStringUTFRegion(name, 0, unicode_len, utfName);
 917         //VerifyFixClassname(utfName);
 918         for (uint i = 0; i < len; i++) {
 919           if (utfName[i] == '.')   utfName[i] = '/';
 920         }
 921     } else {
 922         utfName = NULL;
 923     }
 924 
 925     result = JVM_DefineClass(env, utfName, loader, body, length, pd);
 926 
 927     if (utfName && utfName != buf)
 928         FREE_C_HEAP_ARRAY(char, utfName, mtInternal);
 929 
 930  free_body:
 931     FREE_C_HEAP_ARRAY(jbyte, body, mtInternal);
 932     return result;
 933   }
 934 }
 935 
 936 
 937 UNSAFE_ENTRY(jclass, Unsafe_DefineClass(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd))
 938   UnsafeWrapper("Unsafe_DefineClass");
 939   {
 940     ThreadToNativeFromVM ttnfv(thread);
 941     return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
 942   }
 943 UNSAFE_END
 944 
 945 
 946 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length))
 947   UnsafeWrapper("Unsafe_DefineClass");
 948   {
 949     ThreadToNativeFromVM ttnfv(thread);
 950 
 951     int depthFromDefineClass0 = 1;
 952     jclass  caller = JVM_GetCallerClass(env, depthFromDefineClass0);
 953     jobject loader = (caller == NULL) ? NULL : JVM_GetClassLoader(env, caller);
 954     jobject pd     = (caller == NULL) ? NULL : JVM_GetProtectionDomain(env, caller);
 955 
 956     return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
 957   }
 958 UNSAFE_END
 959 
 960 
 961 #define DAC_Args CLS"[B["OBJ
 962 // define a class but do not make it known to the class loader or system dictionary
 963 // - host_class:  supplies context for linkage, access control, protection domain, and class loader
 964 // - data:  bytes of a class file, a raw memory address (length gives the number of bytes)
 965 // - cp_patches:  where non-null entries exist, they replace corresponding CP entries in data
 966 
 967 // When you load an anonymous class U, it works as if you changed its name just before loading,
 968 // to a name that you will never use again.  Since the name is lost, no other class can directly
 969 // link to any member of U.  Just after U is loaded, the only way to use it is reflectively,
 970 // through java.lang.Class methods like Class.newInstance.
 971 
 972 // Access checks for linkage sites within U continue to follow the same rules as for named classes.
 973 // The package of an anonymous class is given by the package qualifier on the name under which it was loaded.
 974 // An anonymous class also has special privileges to access any member of its host class.
 975 // This is the main reason why this loading operation is unsafe.  The purpose of this is to
 976 // allow language implementations to simulate "open classes"; a host class in effect gets
 977 // new code when an anonymous class is loaded alongside it.  A less convenient but more
 978 // standard way to do this is with reflection, which can also be set to ignore access
 979 // restrictions.
 980 
 981 // Access into an anonymous class is possible only through reflection.  Therefore, there
 982 // are no special access rules for calling into an anonymous class.  The relaxed access
 983 // rule for the host class is applied in the opposite direction:  A host class reflectively
 984 // access one of its anonymous classes.
 985 
 986 // If you load the same bytecodes twice, you get two different classes.  You can reload
 987 // the same bytecodes with or without varying CP patches.
 988 
 989 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
 990 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
 991 // The CONSTANT_Class entry for that name can be patched to refer directly to U1.
 992 
 993 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as
 994 // an outer class (so that U2 is an anonymous inner class of anonymous U1).
 995 // It is not possible for a named class, or an older anonymous class, to refer by
 996 // name (via its CP) to a newer anonymous class.
 997 
 998 // CP patching may also be used to modify (i.e., hack) the names of methods, classes,
 999 // or type descriptors used in the loaded anonymous class.
1000 
1001 // Finally, CP patching may be used to introduce "live" objects into the constant pool,
1002 // instead of "dead" strings.  A compiled statement like println((Object)"hello") can
1003 // be changed to println(greeting), where greeting is an arbitrary object created before
1004 // the anonymous class is loaded.  This is useful in dynamic languages, in which
1005 // various kinds of metaobjects must be introduced as constants into bytecode.
1006 // Note the cast (Object), which tells the verifier to expect an arbitrary object,
1007 // not just a literal string.  For such ldc instructions, the verifier uses the
1008 // type Object instead of String, if the loaded constant is not in fact a String.
1009 
1010 static instanceKlassHandle
1011 Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
1012                                  jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
1013                                  HeapWord* *temp_alloc,
1014                                  TRAPS) {
1015 
1016   if (UsePerfData) {
1017     ClassLoader::unsafe_defineClassCallCounter()->inc();
1018   }
1019 
1020   if (data == NULL) {
1021     THROW_0(vmSymbols::java_lang_NullPointerException());
1022   }
1023 
1024   jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
1025   jint word_length = (length + sizeof(HeapWord)-1) / sizeof(HeapWord);
1026   HeapWord* body = NEW_C_HEAP_ARRAY(HeapWord, word_length, mtInternal);
1027   if (body == NULL) {
1028     THROW_0(vmSymbols::java_lang_OutOfMemoryError());
1029   }
1030 
1031   // caller responsible to free it:
1032   (*temp_alloc) = body;
1033 
1034   {
1035     jbyte* array_base = typeArrayOop(JNIHandles::resolve_non_null(data))->byte_at_addr(0);
1036     Copy::conjoint_words((HeapWord*) array_base, body, word_length);
1037   }
1038 
1039   u1* class_bytes = (u1*) body;
1040   int class_bytes_length = (int) length;
1041   if (class_bytes_length < 0)  class_bytes_length = 0;
1042   if (class_bytes == NULL
1043       || host_class == NULL
1044       || length != class_bytes_length)
1045     THROW_0(vmSymbols::java_lang_IllegalArgumentException());
1046 
1047   objArrayHandle cp_patches_h;
1048   if (cp_patches_jh != NULL) {
1049     oop p = JNIHandles::resolve_non_null(cp_patches_jh);
1050     if (!p->is_objArray())
1051       THROW_0(vmSymbols::java_lang_IllegalArgumentException());
1052     cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
1053   }
1054 
1055   KlassHandle host_klass(THREAD, java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class)));
1056   const char* host_source = host_klass->external_name();
1057   Handle      host_loader(THREAD, host_klass->class_loader());
1058   Handle      host_domain(THREAD, host_klass->protection_domain());
1059 
1060   GrowableArray<Handle>* cp_patches = NULL;
1061   if (cp_patches_h.not_null()) {
1062     int alen = cp_patches_h->length();
1063     for (int i = alen-1; i >= 0; i--) {
1064       oop p = cp_patches_h->obj_at(i);
1065       if (p != NULL) {
1066         Handle patch(THREAD, p);
1067         if (cp_patches == NULL)
1068           cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
1069         cp_patches->at_put(i, patch);
1070       }
1071     }
1072   }
1073 
1074   ClassFileStream st(class_bytes, class_bytes_length, (char*) host_source);
1075 
1076   instanceKlassHandle anon_klass;
1077   {
1078     Symbol* no_class_name = NULL;
1079     Klass* anonk = SystemDictionary::parse_stream(no_class_name,
1080                                                     host_loader, host_domain,
1081                                                     &st, host_klass, cp_patches,
1082                                                     CHECK_NULL);
1083     if (anonk == NULL)  return NULL;
1084     anon_klass = instanceKlassHandle(THREAD, anonk);
1085   }
1086 
1087   return anon_klass;
1088 }
1089 
1090 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh))
1091 {
1092   instanceKlassHandle anon_klass;
1093   jobject res_jh = NULL;
1094 
1095   UnsafeWrapper("Unsafe_DefineAnonymousClass");
1096   ResourceMark rm(THREAD);
1097 
1098   HeapWord* temp_alloc = NULL;
1099 
1100   anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data,
1101                                                 cp_patches_jh,
1102                                                    &temp_alloc, THREAD);
1103   if (anon_klass() != NULL)
1104     res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
1105 
1106   // try/finally clause:
1107   if (temp_alloc != NULL) {
1108     FREE_C_HEAP_ARRAY(HeapWord, temp_alloc, mtInternal);
1109   }
1110 
1111   // The anonymous class loader data has been artificially been kept alive to
1112   // this point.   The mirror and any instances of this class have to keep
1113   // it alive afterwards.
1114   if (anon_klass() != NULL) {
1115     anon_klass->class_loader_data()->set_keep_alive(false);
1116   }
1117 
1118   // let caller initialize it as needed...
1119 
1120   return (jclass) res_jh;
1121 }
1122 UNSAFE_END
1123 
1124 
1125 
1126 UNSAFE_ENTRY(void, Unsafe_MonitorEnter(JNIEnv *env, jobject unsafe, jobject jobj))
1127   UnsafeWrapper("Unsafe_MonitorEnter");
1128   {
1129     if (jobj == NULL) {
1130       THROW(vmSymbols::java_lang_NullPointerException());
1131     }
1132     Handle obj(thread, JNIHandles::resolve_non_null(jobj));
1133     ObjectSynchronizer::jni_enter(obj, CHECK);
1134   }
1135 UNSAFE_END
1136 
1137 
1138 UNSAFE_ENTRY(jboolean, Unsafe_TryMonitorEnter(JNIEnv *env, jobject unsafe, jobject jobj))
1139   UnsafeWrapper("Unsafe_TryMonitorEnter");
1140   {
1141     if (jobj == NULL) {
1142       THROW_(vmSymbols::java_lang_NullPointerException(), JNI_FALSE);
1143     }
1144     Handle obj(thread, JNIHandles::resolve_non_null(jobj));
1145     bool res = ObjectSynchronizer::jni_try_enter(obj, CHECK_0);
1146     return (res ? JNI_TRUE : JNI_FALSE);
1147   }
1148 UNSAFE_END
1149 
1150 
1151 UNSAFE_ENTRY(void, Unsafe_MonitorExit(JNIEnv *env, jobject unsafe, jobject jobj))
1152   UnsafeWrapper("Unsafe_MonitorExit");
1153   {
1154     if (jobj == NULL) {
1155       THROW(vmSymbols::java_lang_NullPointerException());
1156     }
1157     Handle obj(THREAD, JNIHandles::resolve_non_null(jobj));
1158     ObjectSynchronizer::jni_exit(obj(), CHECK);
1159   }
1160 UNSAFE_END
1161 
1162 
1163 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr))
1164   UnsafeWrapper("Unsafe_ThrowException");
1165   {
1166     ThreadToNativeFromVM ttnfv(thread);
1167     env->Throw(thr);
1168   }
1169 UNSAFE_END
1170 
1171 // JSR166 ------------------------------------------------------------------
1172 
1173 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h))
1174   UnsafeWrapper("Unsafe_CompareAndSwapObject");
1175   oop x = JNIHandles::resolve(x_h);
1176   oop e = JNIHandles::resolve(e_h);
1177   oop p = JNIHandles::resolve(obj);
1178   HeapWord* addr = (HeapWord *)index_oop_from_field_offset_long(p, offset);
1179   oop res = oopDesc::atomic_compare_exchange_oop(x, addr, e, true);
1180   jboolean success  = (res == e);
1181   if (success)
1182     update_barrier_set((void*)addr, x);
1183   return success;
1184 UNSAFE_END
1185 
1186 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x))
1187   UnsafeWrapper("Unsafe_CompareAndSwapInt");
1188   oop p = JNIHandles::resolve(obj);
1189   jint* addr = (jint *) index_oop_from_field_offset_long(p, offset);
1190   return (jint)(Atomic::cmpxchg(x, addr, e)) == e;
1191 UNSAFE_END
1192 
1193 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x))
1194   UnsafeWrapper("Unsafe_CompareAndSwapLong");
1195   Handle p (THREAD, JNIHandles::resolve(obj));
1196   jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
1197   if (VM_Version::supports_cx8())
1198     return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
1199   else {
1200     jboolean success = false;
1201     ObjectLocker ol(p, THREAD);
1202     if (*addr == e) { *addr = x; success = true; }
1203     return success;
1204   }
1205 UNSAFE_END
1206 
1207 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time))
1208   UnsafeWrapper("Unsafe_Park");
1209 #ifndef USDT2
1210   HS_DTRACE_PROBE3(hotspot, thread__park__begin, thread->parker(), (int) isAbsolute, time);
1211 #else /* USDT2 */
1212    HOTSPOT_THREAD_PARK_BEGIN(
1213                              (uintptr_t) thread->parker(), (int) isAbsolute, time);
1214 #endif /* USDT2 */
1215   JavaThreadParkedState jtps(thread, time != 0);
1216   thread->parker()->park(isAbsolute != 0, time);
1217 #ifndef USDT2
1218   HS_DTRACE_PROBE1(hotspot, thread__park__end, thread->parker());
1219 #else /* USDT2 */
1220   HOTSPOT_THREAD_PARK_END(
1221                           (uintptr_t) thread->parker());
1222 #endif /* USDT2 */
1223 UNSAFE_END
1224 
1225 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread))
1226   UnsafeWrapper("Unsafe_Unpark");
1227   Parker* p = NULL;
1228   if (jthread != NULL) {
1229     oop java_thread = JNIHandles::resolve_non_null(jthread);
1230     if (java_thread != NULL) {
1231       jlong lp = java_lang_Thread::park_event(java_thread);
1232       if (lp != 0) {
1233         // This cast is OK even though the jlong might have been read
1234         // non-atomically on 32bit systems, since there, one word will
1235         // always be zero anyway and the value set is always the same
1236         p = (Parker*)addr_from_java(lp);
1237       } else {
1238         // Grab lock if apparently null or using older version of library
1239         MutexLocker mu(Threads_lock);
1240         java_thread = JNIHandles::resolve_non_null(jthread);
1241         if (java_thread != NULL) {
1242           JavaThread* thr = java_lang_Thread::thread(java_thread);
1243           if (thr != NULL) {
1244             p = thr->parker();
1245             if (p != NULL) { // Bind to Java thread for next time.
1246               java_lang_Thread::set_park_event(java_thread, addr_to_java(p));
1247             }
1248           }
1249         }
1250       }
1251     }
1252   }
1253   if (p != NULL) {
1254 #ifndef USDT2
1255     HS_DTRACE_PROBE1(hotspot, thread__unpark, p);
1256 #else /* USDT2 */
1257     HOTSPOT_THREAD_UNPARK(
1258                           (uintptr_t) p);
1259 #endif /* USDT2 */
1260     p->unpark();
1261   }
1262 UNSAFE_END
1263 
1264 UNSAFE_ENTRY(jint, Unsafe_Loadavg(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem))
1265   UnsafeWrapper("Unsafe_Loadavg");
1266   const int max_nelem = 3;
1267   double la[max_nelem];
1268   jint ret;
1269 
1270   typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
1271   assert(a->is_typeArray(), "must be type array");
1272 
1273   if (nelem < 0 || nelem > max_nelem || a->length() < nelem) {
1274     ThreadToNativeFromVM ttnfv(thread);
1275     throw_new(env, "ArrayIndexOutOfBoundsException");
1276     return -1;
1277   }
1278 
1279   ret = os::loadavg(la, nelem);
1280   if (ret == -1) return -1;
1281 
1282   // if successful, ret is the number of samples actually retrieved.
1283   assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
1284   switch(ret) {
1285     case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
1286     case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
1287     case 1: a->double_at_put(0, (jdouble)la[0]); break;
1288   }
1289   return ret;
1290 UNSAFE_END
1291 
1292 UNSAFE_ENTRY(void, Unsafe_PrefetchRead(JNIEnv* env, jclass ignored, jobject obj, jlong offset))
1293   UnsafeWrapper("Unsafe_PrefetchRead");
1294   oop p = JNIHandles::resolve(obj);
1295   void* addr = index_oop_from_field_offset_long(p, 0);
1296   Prefetch::read(addr, (intx)offset);
1297 UNSAFE_END
1298 
1299 UNSAFE_ENTRY(void, Unsafe_PrefetchWrite(JNIEnv* env, jclass ignored, jobject obj, jlong offset))
1300   UnsafeWrapper("Unsafe_PrefetchWrite");
1301   oop p = JNIHandles::resolve(obj);
1302   void* addr = index_oop_from_field_offset_long(p, 0);
1303   Prefetch::write(addr, (intx)offset);
1304 UNSAFE_END
1305 
1306 
1307 /// JVM_RegisterUnsafeMethods
1308 
1309 #define ADR "J"
1310 
1311 #define LANG "Ljava/lang/"
1312 
1313 #define OBJ LANG"Object;"
1314 #define CLS LANG"Class;"
1315 #define CTR LANG"reflect/Constructor;"
1316 #define FLD LANG"reflect/Field;"
1317 #define MTH LANG"reflect/Method;"
1318 #define THR LANG"Throwable;"
1319 
1320 #define DC0_Args LANG"String;[BII"
1321 #define DC_Args  DC0_Args LANG"ClassLoader;" "Ljava/security/ProtectionDomain;"
1322 
1323 #define CC (char*)  /*cast a literal from (const char*)*/
1324 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
1325 
1326 // define deprecated accessors for compabitility with 1.4.0
1327 #define DECLARE_GETSETOOP_140(Boolean, Z) \
1328     {CC"get"#Boolean,      CC"("OBJ"I)"#Z,      FN_PTR(Unsafe_Get##Boolean##140)}, \
1329     {CC"put"#Boolean,      CC"("OBJ"I"#Z")V",   FN_PTR(Unsafe_Set##Boolean##140)}
1330 
1331 // Note:  In 1.4.1, getObject and kin take both int and long offsets.
1332 #define DECLARE_GETSETOOP_141(Boolean, Z) \
1333     {CC"get"#Boolean,      CC"("OBJ"J)"#Z,      FN_PTR(Unsafe_Get##Boolean)}, \
1334     {CC"put"#Boolean,      CC"("OBJ"J"#Z")V",   FN_PTR(Unsafe_Set##Boolean)}
1335 
1336 // Note:  In 1.5.0, there are volatile versions too
1337 #define DECLARE_GETSETOOP(Boolean, Z) \
1338     {CC"get"#Boolean,      CC"("OBJ"J)"#Z,      FN_PTR(Unsafe_Get##Boolean)}, \
1339     {CC"put"#Boolean,      CC"("OBJ"J"#Z")V",   FN_PTR(Unsafe_Set##Boolean)}, \
1340     {CC"get"#Boolean"Volatile",      CC"("OBJ"J)"#Z,      FN_PTR(Unsafe_Get##Boolean##Volatile)}, \
1341     {CC"put"#Boolean"Volatile",      CC"("OBJ"J"#Z")V",   FN_PTR(Unsafe_Set##Boolean##Volatile)}
1342 
1343 
1344 #define DECLARE_GETSETNATIVE(Byte, B) \
1345     {CC"get"#Byte,         CC"("ADR")"#B,       FN_PTR(Unsafe_GetNative##Byte)}, \
1346     {CC"put"#Byte,         CC"("ADR#B")V",      FN_PTR(Unsafe_SetNative##Byte)}
1347 
1348 
1349 
1350 // These are the methods for 1.4.0
1351 static JNINativeMethod methods_140[] = {
1352     {CC"getObject",        CC"("OBJ"I)"OBJ"",   FN_PTR(Unsafe_GetObject140)},
1353     {CC"putObject",        CC"("OBJ"I"OBJ")V",  FN_PTR(Unsafe_SetObject140)},
1354 
1355     DECLARE_GETSETOOP_140(Boolean, Z),
1356     DECLARE_GETSETOOP_140(Byte, B),
1357     DECLARE_GETSETOOP_140(Short, S),
1358     DECLARE_GETSETOOP_140(Char, C),
1359     DECLARE_GETSETOOP_140(Int, I),
1360     DECLARE_GETSETOOP_140(Long, J),
1361     DECLARE_GETSETOOP_140(Float, F),
1362     DECLARE_GETSETOOP_140(Double, D),
1363 
1364     DECLARE_GETSETNATIVE(Byte, B),
1365     DECLARE_GETSETNATIVE(Short, S),
1366     DECLARE_GETSETNATIVE(Char, C),
1367     DECLARE_GETSETNATIVE(Int, I),
1368     DECLARE_GETSETNATIVE(Long, J),
1369     DECLARE_GETSETNATIVE(Float, F),
1370     DECLARE_GETSETNATIVE(Double, D),
1371 
1372     {CC"getAddress",         CC"("ADR")"ADR,             FN_PTR(Unsafe_GetNativeAddress)},
1373     {CC"putAddress",         CC"("ADR""ADR")V",          FN_PTR(Unsafe_SetNativeAddress)},
1374 
1375     {CC"allocateMemory",     CC"(J)"ADR,                 FN_PTR(Unsafe_AllocateMemory)},
1376     {CC"reallocateMemory",   CC"("ADR"J)"ADR,            FN_PTR(Unsafe_ReallocateMemory)},
1377     {CC"freeMemory",         CC"("ADR")V",               FN_PTR(Unsafe_FreeMemory)},
1378 
1379     {CC"fieldOffset",        CC"("FLD")I",               FN_PTR(Unsafe_FieldOffset)},
1380     {CC"staticFieldBase",    CC"("CLS")"OBJ,             FN_PTR(Unsafe_StaticFieldBaseFromClass)},
1381     {CC"ensureClassInitialized",CC"("CLS")V",            FN_PTR(Unsafe_EnsureClassInitialized)},
1382     {CC"arrayBaseOffset",    CC"("CLS")I",               FN_PTR(Unsafe_ArrayBaseOffset)},
1383     {CC"arrayIndexScale",    CC"("CLS")I",               FN_PTR(Unsafe_ArrayIndexScale)},
1384     {CC"addressSize",        CC"()I",                    FN_PTR(Unsafe_AddressSize)},
1385     {CC"pageSize",           CC"()I",                    FN_PTR(Unsafe_PageSize)},
1386 
1387     {CC"defineClass",        CC"("DC0_Args")"CLS,        FN_PTR(Unsafe_DefineClass0)},
1388     {CC"defineClass",        CC"("DC_Args")"CLS,         FN_PTR(Unsafe_DefineClass)},
1389     {CC"allocateInstance",   CC"("CLS")"OBJ,             FN_PTR(Unsafe_AllocateInstance)},
1390     {CC"monitorEnter",       CC"("OBJ")V",               FN_PTR(Unsafe_MonitorEnter)},
1391     {CC"monitorExit",        CC"("OBJ")V",               FN_PTR(Unsafe_MonitorExit)},
1392     {CC"throwException",     CC"("THR")V",               FN_PTR(Unsafe_ThrowException)}
1393 };
1394 
1395 // These are the methods prior to the JSR 166 changes in 1.5.0
1396 static JNINativeMethod methods_141[] = {
1397     {CC"getObject",        CC"("OBJ"J)"OBJ"",   FN_PTR(Unsafe_GetObject)},
1398     {CC"putObject",        CC"("OBJ"J"OBJ")V",  FN_PTR(Unsafe_SetObject)},
1399 
1400     DECLARE_GETSETOOP_141(Boolean, Z),
1401     DECLARE_GETSETOOP_141(Byte, B),
1402     DECLARE_GETSETOOP_141(Short, S),
1403     DECLARE_GETSETOOP_141(Char, C),
1404     DECLARE_GETSETOOP_141(Int, I),
1405     DECLARE_GETSETOOP_141(Long, J),
1406     DECLARE_GETSETOOP_141(Float, F),
1407     DECLARE_GETSETOOP_141(Double, D),
1408 
1409     DECLARE_GETSETNATIVE(Byte, B),
1410     DECLARE_GETSETNATIVE(Short, S),
1411     DECLARE_GETSETNATIVE(Char, C),
1412     DECLARE_GETSETNATIVE(Int, I),
1413     DECLARE_GETSETNATIVE(Long, J),
1414     DECLARE_GETSETNATIVE(Float, F),
1415     DECLARE_GETSETNATIVE(Double, D),
1416 
1417     {CC"getAddress",         CC"("ADR")"ADR,             FN_PTR(Unsafe_GetNativeAddress)},
1418     {CC"putAddress",         CC"("ADR""ADR")V",          FN_PTR(Unsafe_SetNativeAddress)},
1419 
1420     {CC"allocateMemory",     CC"(J)"ADR,                 FN_PTR(Unsafe_AllocateMemory)},
1421     {CC"reallocateMemory",   CC"("ADR"J)"ADR,            FN_PTR(Unsafe_ReallocateMemory)},
1422     {CC"freeMemory",         CC"("ADR")V",               FN_PTR(Unsafe_FreeMemory)},
1423 
1424     {CC"objectFieldOffset",  CC"("FLD")J",               FN_PTR(Unsafe_ObjectFieldOffset)},
1425     {CC"staticFieldOffset",  CC"("FLD")J",               FN_PTR(Unsafe_StaticFieldOffset)},
1426     {CC"staticFieldBase",    CC"("FLD")"OBJ,             FN_PTR(Unsafe_StaticFieldBaseFromField)},
1427     {CC"ensureClassInitialized",CC"("CLS")V",            FN_PTR(Unsafe_EnsureClassInitialized)},
1428     {CC"arrayBaseOffset",    CC"("CLS")I",               FN_PTR(Unsafe_ArrayBaseOffset)},
1429     {CC"arrayIndexScale",    CC"("CLS")I",               FN_PTR(Unsafe_ArrayIndexScale)},
1430     {CC"addressSize",        CC"()I",                    FN_PTR(Unsafe_AddressSize)},
1431     {CC"pageSize",           CC"()I",                    FN_PTR(Unsafe_PageSize)},
1432 
1433     {CC"defineClass",        CC"("DC0_Args")"CLS,        FN_PTR(Unsafe_DefineClass0)},
1434     {CC"defineClass",        CC"("DC_Args")"CLS,         FN_PTR(Unsafe_DefineClass)},
1435     {CC"allocateInstance",   CC"("CLS")"OBJ,             FN_PTR(Unsafe_AllocateInstance)},
1436     {CC"monitorEnter",       CC"("OBJ")V",               FN_PTR(Unsafe_MonitorEnter)},
1437     {CC"monitorExit",        CC"("OBJ")V",               FN_PTR(Unsafe_MonitorExit)},
1438     {CC"throwException",     CC"("THR")V",               FN_PTR(Unsafe_ThrowException)}
1439 
1440 };
1441 
1442 // These are the methods prior to the JSR 166 changes in 1.6.0
1443 static JNINativeMethod methods_15[] = {
1444     {CC"getObject",        CC"("OBJ"J)"OBJ"",   FN_PTR(Unsafe_GetObject)},
1445     {CC"putObject",        CC"("OBJ"J"OBJ")V",  FN_PTR(Unsafe_SetObject)},
1446     {CC"getObjectVolatile",CC"("OBJ"J)"OBJ"",   FN_PTR(Unsafe_GetObjectVolatile)},
1447     {CC"putObjectVolatile",CC"("OBJ"J"OBJ")V",  FN_PTR(Unsafe_SetObjectVolatile)},
1448 
1449 
1450     DECLARE_GETSETOOP(Boolean, Z),
1451     DECLARE_GETSETOOP(Byte, B),
1452     DECLARE_GETSETOOP(Short, S),
1453     DECLARE_GETSETOOP(Char, C),
1454     DECLARE_GETSETOOP(Int, I),
1455     DECLARE_GETSETOOP(Long, J),
1456     DECLARE_GETSETOOP(Float, F),
1457     DECLARE_GETSETOOP(Double, D),
1458 
1459     DECLARE_GETSETNATIVE(Byte, B),
1460     DECLARE_GETSETNATIVE(Short, S),
1461     DECLARE_GETSETNATIVE(Char, C),
1462     DECLARE_GETSETNATIVE(Int, I),
1463     DECLARE_GETSETNATIVE(Long, J),
1464     DECLARE_GETSETNATIVE(Float, F),
1465     DECLARE_GETSETNATIVE(Double, D),
1466 
1467     {CC"getAddress",         CC"("ADR")"ADR,             FN_PTR(Unsafe_GetNativeAddress)},
1468     {CC"putAddress",         CC"("ADR""ADR")V",          FN_PTR(Unsafe_SetNativeAddress)},
1469 
1470     {CC"allocateMemory",     CC"(J)"ADR,                 FN_PTR(Unsafe_AllocateMemory)},
1471     {CC"reallocateMemory",   CC"("ADR"J)"ADR,            FN_PTR(Unsafe_ReallocateMemory)},
1472     {CC"freeMemory",         CC"("ADR")V",               FN_PTR(Unsafe_FreeMemory)},
1473 
1474     {CC"objectFieldOffset",  CC"("FLD")J",               FN_PTR(Unsafe_ObjectFieldOffset)},
1475     {CC"staticFieldOffset",  CC"("FLD")J",               FN_PTR(Unsafe_StaticFieldOffset)},
1476     {CC"staticFieldBase",    CC"("FLD")"OBJ,             FN_PTR(Unsafe_StaticFieldBaseFromField)},
1477     {CC"ensureClassInitialized",CC"("CLS")V",            FN_PTR(Unsafe_EnsureClassInitialized)},
1478     {CC"arrayBaseOffset",    CC"("CLS")I",               FN_PTR(Unsafe_ArrayBaseOffset)},
1479     {CC"arrayIndexScale",    CC"("CLS")I",               FN_PTR(Unsafe_ArrayIndexScale)},
1480     {CC"addressSize",        CC"()I",                    FN_PTR(Unsafe_AddressSize)},
1481     {CC"pageSize",           CC"()I",                    FN_PTR(Unsafe_PageSize)},
1482 
1483     {CC"defineClass",        CC"("DC0_Args")"CLS,        FN_PTR(Unsafe_DefineClass0)},
1484     {CC"defineClass",        CC"("DC_Args")"CLS,         FN_PTR(Unsafe_DefineClass)},
1485     {CC"allocateInstance",   CC"("CLS")"OBJ,             FN_PTR(Unsafe_AllocateInstance)},
1486     {CC"monitorEnter",       CC"("OBJ")V",               FN_PTR(Unsafe_MonitorEnter)},
1487     {CC"monitorExit",        CC"("OBJ")V",               FN_PTR(Unsafe_MonitorExit)},
1488     {CC"throwException",     CC"("THR")V",               FN_PTR(Unsafe_ThrowException)},
1489     {CC"compareAndSwapObject", CC"("OBJ"J"OBJ""OBJ")Z",  FN_PTR(Unsafe_CompareAndSwapObject)},
1490     {CC"compareAndSwapInt",  CC"("OBJ"J""I""I"")Z",      FN_PTR(Unsafe_CompareAndSwapInt)},
1491     {CC"compareAndSwapLong", CC"("OBJ"J""J""J"")Z",      FN_PTR(Unsafe_CompareAndSwapLong)},
1492     {CC"park",               CC"(ZJ)V",                  FN_PTR(Unsafe_Park)},
1493     {CC"unpark",             CC"("OBJ")V",               FN_PTR(Unsafe_Unpark)}
1494 
1495 };
1496 
1497 // These are the methods for 1.6.0 and 1.7.0
1498 static JNINativeMethod methods_16[] = {
1499     {CC"getObject",        CC"("OBJ"J)"OBJ"",   FN_PTR(Unsafe_GetObject)},
1500     {CC"putObject",        CC"("OBJ"J"OBJ")V",  FN_PTR(Unsafe_SetObject)},
1501     {CC"getObjectVolatile",CC"("OBJ"J)"OBJ"",   FN_PTR(Unsafe_GetObjectVolatile)},
1502     {CC"putObjectVolatile",CC"("OBJ"J"OBJ")V",  FN_PTR(Unsafe_SetObjectVolatile)},
1503 
1504     DECLARE_GETSETOOP(Boolean, Z),
1505     DECLARE_GETSETOOP(Byte, B),
1506     DECLARE_GETSETOOP(Short, S),
1507     DECLARE_GETSETOOP(Char, C),
1508     DECLARE_GETSETOOP(Int, I),
1509     DECLARE_GETSETOOP(Long, J),
1510     DECLARE_GETSETOOP(Float, F),
1511     DECLARE_GETSETOOP(Double, D),
1512 
1513     DECLARE_GETSETNATIVE(Byte, B),
1514     DECLARE_GETSETNATIVE(Short, S),
1515     DECLARE_GETSETNATIVE(Char, C),
1516     DECLARE_GETSETNATIVE(Int, I),
1517     DECLARE_GETSETNATIVE(Long, J),
1518     DECLARE_GETSETNATIVE(Float, F),
1519     DECLARE_GETSETNATIVE(Double, D),
1520 
1521     {CC"getAddress",         CC"("ADR")"ADR,             FN_PTR(Unsafe_GetNativeAddress)},
1522     {CC"putAddress",         CC"("ADR""ADR")V",          FN_PTR(Unsafe_SetNativeAddress)},
1523 
1524     {CC"allocateMemory",     CC"(J)"ADR,                 FN_PTR(Unsafe_AllocateMemory)},
1525     {CC"reallocateMemory",   CC"("ADR"J)"ADR,            FN_PTR(Unsafe_ReallocateMemory)},
1526     {CC"freeMemory",         CC"("ADR")V",               FN_PTR(Unsafe_FreeMemory)},
1527 
1528     {CC"objectFieldOffset",  CC"("FLD")J",               FN_PTR(Unsafe_ObjectFieldOffset)},
1529     {CC"staticFieldOffset",  CC"("FLD")J",               FN_PTR(Unsafe_StaticFieldOffset)},
1530     {CC"staticFieldBase",    CC"("FLD")"OBJ,             FN_PTR(Unsafe_StaticFieldBaseFromField)},
1531     {CC"ensureClassInitialized",CC"("CLS")V",            FN_PTR(Unsafe_EnsureClassInitialized)},
1532     {CC"arrayBaseOffset",    CC"("CLS")I",               FN_PTR(Unsafe_ArrayBaseOffset)},
1533     {CC"arrayIndexScale",    CC"("CLS")I",               FN_PTR(Unsafe_ArrayIndexScale)},
1534     {CC"addressSize",        CC"()I",                    FN_PTR(Unsafe_AddressSize)},
1535     {CC"pageSize",           CC"()I",                    FN_PTR(Unsafe_PageSize)},
1536 
1537     {CC"defineClass",        CC"("DC0_Args")"CLS,        FN_PTR(Unsafe_DefineClass0)},
1538     {CC"defineClass",        CC"("DC_Args")"CLS,         FN_PTR(Unsafe_DefineClass)},
1539     {CC"allocateInstance",   CC"("CLS")"OBJ,             FN_PTR(Unsafe_AllocateInstance)},
1540     {CC"monitorEnter",       CC"("OBJ")V",               FN_PTR(Unsafe_MonitorEnter)},
1541     {CC"monitorExit",        CC"("OBJ")V",               FN_PTR(Unsafe_MonitorExit)},
1542     {CC"tryMonitorEnter",    CC"("OBJ")Z",               FN_PTR(Unsafe_TryMonitorEnter)},
1543     {CC"throwException",     CC"("THR")V",               FN_PTR(Unsafe_ThrowException)},
1544     {CC"compareAndSwapObject", CC"("OBJ"J"OBJ""OBJ")Z",  FN_PTR(Unsafe_CompareAndSwapObject)},
1545     {CC"compareAndSwapInt",  CC"("OBJ"J""I""I"")Z",      FN_PTR(Unsafe_CompareAndSwapInt)},
1546     {CC"compareAndSwapLong", CC"("OBJ"J""J""J"")Z",      FN_PTR(Unsafe_CompareAndSwapLong)},
1547     {CC"putOrderedObject",   CC"("OBJ"J"OBJ")V",         FN_PTR(Unsafe_SetOrderedObject)},
1548     {CC"putOrderedInt",      CC"("OBJ"JI)V",             FN_PTR(Unsafe_SetOrderedInt)},
1549     {CC"putOrderedLong",     CC"("OBJ"JJ)V",             FN_PTR(Unsafe_SetOrderedLong)},
1550     {CC"park",               CC"(ZJ)V",                  FN_PTR(Unsafe_Park)},
1551     {CC"unpark",             CC"("OBJ")V",               FN_PTR(Unsafe_Unpark)}
1552 };
1553 
1554 // These are the methods for 1.8.0
1555 static JNINativeMethod methods_18[] = {
1556     {CC"getObject",        CC"("OBJ"J)"OBJ"",   FN_PTR(Unsafe_GetObject)},
1557     {CC"putObject",        CC"("OBJ"J"OBJ")V",  FN_PTR(Unsafe_SetObject)},
1558     {CC"getObjectVolatile",CC"("OBJ"J)"OBJ"",   FN_PTR(Unsafe_GetObjectVolatile)},
1559     {CC"putObjectVolatile",CC"("OBJ"J"OBJ")V",  FN_PTR(Unsafe_SetObjectVolatile)},
1560 
1561     DECLARE_GETSETOOP(Boolean, Z),
1562     DECLARE_GETSETOOP(Byte, B),
1563     DECLARE_GETSETOOP(Short, S),
1564     DECLARE_GETSETOOP(Char, C),
1565     DECLARE_GETSETOOP(Int, I),
1566     DECLARE_GETSETOOP(Long, J),
1567     DECLARE_GETSETOOP(Float, F),
1568     DECLARE_GETSETOOP(Double, D),
1569 
1570     DECLARE_GETSETNATIVE(Byte, B),
1571     DECLARE_GETSETNATIVE(Short, S),
1572     DECLARE_GETSETNATIVE(Char, C),
1573     DECLARE_GETSETNATIVE(Int, I),
1574     DECLARE_GETSETNATIVE(Long, J),
1575     DECLARE_GETSETNATIVE(Float, F),
1576     DECLARE_GETSETNATIVE(Double, D),
1577 
1578     {CC"getAddress",         CC"("ADR")"ADR,             FN_PTR(Unsafe_GetNativeAddress)},
1579     {CC"putAddress",         CC"("ADR""ADR")V",          FN_PTR(Unsafe_SetNativeAddress)},
1580 
1581     {CC"allocateMemory",     CC"(J)"ADR,                 FN_PTR(Unsafe_AllocateMemory)},
1582     {CC"reallocateMemory",   CC"("ADR"J)"ADR,            FN_PTR(Unsafe_ReallocateMemory)},
1583     {CC"freeMemory",         CC"("ADR")V",               FN_PTR(Unsafe_FreeMemory)},
1584 
1585     {CC"objectFieldOffset",  CC"("FLD")J",               FN_PTR(Unsafe_ObjectFieldOffset)},
1586     {CC"staticFieldOffset",  CC"("FLD")J",               FN_PTR(Unsafe_StaticFieldOffset)},
1587     {CC"staticFieldBase",    CC"("FLD")"OBJ,             FN_PTR(Unsafe_StaticFieldBaseFromField)},
1588     {CC"ensureClassInitialized",CC"("CLS")V",            FN_PTR(Unsafe_EnsureClassInitialized)},
1589     {CC"arrayBaseOffset",    CC"("CLS")I",               FN_PTR(Unsafe_ArrayBaseOffset)},
1590     {CC"arrayIndexScale",    CC"("CLS")I",               FN_PTR(Unsafe_ArrayIndexScale)},
1591     {CC"addressSize",        CC"()I",                    FN_PTR(Unsafe_AddressSize)},
1592     {CC"pageSize",           CC"()I",                    FN_PTR(Unsafe_PageSize)},
1593 
1594     {CC"defineClass",        CC"("DC_Args")"CLS,         FN_PTR(Unsafe_DefineClass)},
1595     {CC"allocateInstance",   CC"("CLS")"OBJ,             FN_PTR(Unsafe_AllocateInstance)},
1596     {CC"monitorEnter",       CC"("OBJ")V",               FN_PTR(Unsafe_MonitorEnter)},
1597     {CC"monitorExit",        CC"("OBJ")V",               FN_PTR(Unsafe_MonitorExit)},
1598     {CC"tryMonitorEnter",    CC"("OBJ")Z",               FN_PTR(Unsafe_TryMonitorEnter)},
1599     {CC"throwException",     CC"("THR")V",               FN_PTR(Unsafe_ThrowException)},
1600     {CC"compareAndSwapObject", CC"("OBJ"J"OBJ""OBJ")Z",  FN_PTR(Unsafe_CompareAndSwapObject)},
1601     {CC"compareAndSwapInt",  CC"("OBJ"J""I""I"")Z",      FN_PTR(Unsafe_CompareAndSwapInt)},
1602     {CC"compareAndSwapLong", CC"("OBJ"J""J""J"")Z",      FN_PTR(Unsafe_CompareAndSwapLong)},
1603     {CC"putOrderedObject",   CC"("OBJ"J"OBJ")V",         FN_PTR(Unsafe_SetOrderedObject)},
1604     {CC"putOrderedInt",      CC"("OBJ"JI)V",             FN_PTR(Unsafe_SetOrderedInt)},
1605     {CC"putOrderedLong",     CC"("OBJ"JJ)V",             FN_PTR(Unsafe_SetOrderedLong)},
1606     {CC"park",               CC"(ZJ)V",                  FN_PTR(Unsafe_Park)},
1607     {CC"unpark",             CC"("OBJ")V",               FN_PTR(Unsafe_Unpark)}
1608 };
1609 
1610 JNINativeMethod loadavg_method[] = {
1611     {CC"getLoadAverage",     CC"([DI)I",                 FN_PTR(Unsafe_Loadavg)}
1612 };
1613 
1614 JNINativeMethod prefetch_methods[] = {
1615     {CC"prefetchRead",       CC"("OBJ"J)V",              FN_PTR(Unsafe_PrefetchRead)},
1616     {CC"prefetchWrite",      CC"("OBJ"J)V",              FN_PTR(Unsafe_PrefetchWrite)},
1617     {CC"prefetchReadStatic", CC"("OBJ"J)V",              FN_PTR(Unsafe_PrefetchRead)},
1618     {CC"prefetchWriteStatic",CC"("OBJ"J)V",              FN_PTR(Unsafe_PrefetchWrite)}
1619 };
1620 
1621 JNINativeMethod memcopy_methods_17[] = {
1622     {CC"copyMemory",         CC"("OBJ"J"OBJ"JJ)V",       FN_PTR(Unsafe_CopyMemory2)},
1623     {CC"setMemory",          CC"("OBJ"JJB)V",            FN_PTR(Unsafe_SetMemory2)}
1624 };
1625 
1626 JNINativeMethod memcopy_methods_15[] = {
1627     {CC"setMemory",          CC"("ADR"JB)V",             FN_PTR(Unsafe_SetMemory)},
1628     {CC"copyMemory",         CC"("ADR ADR"J)V",          FN_PTR(Unsafe_CopyMemory)}
1629 };
1630 
1631 JNINativeMethod anonk_methods[] = {
1632     {CC"defineAnonymousClass", CC"("DAC_Args")"CLS,      FN_PTR(Unsafe_DefineAnonymousClass)},
1633 };
1634 
1635 JNINativeMethod lform_methods[] = {
1636     {CC"shouldBeInitialized",CC"("CLS")Z",               FN_PTR(Unsafe_ShouldBeInitialized)},
1637 };
1638 
1639 JNINativeMethod fence_methods[] = {
1640     {CC"loadFence",          CC"()V",                    FN_PTR(Unsafe_LoadFence)},
1641     {CC"storeFence",         CC"()V",                    FN_PTR(Unsafe_StoreFence)},
1642     {CC"fullFence",          CC"()V",                    FN_PTR(Unsafe_FullFence)},
1643 };
1644 
1645 #undef CC
1646 #undef FN_PTR
1647 
1648 #undef ADR
1649 #undef LANG
1650 #undef OBJ
1651 #undef CLS
1652 #undef CTR
1653 #undef FLD
1654 #undef MTH
1655 #undef THR
1656 #undef DC0_Args
1657 #undef DC_Args
1658 
1659 #undef DECLARE_GETSETOOP
1660 #undef DECLARE_GETSETNATIVE
1661 
1662 
1663 /**
1664  * Helper method to register native methods.
1665  */
1666 static bool register_natives(const char* message, JNIEnv* env, jclass clazz, const JNINativeMethod* methods, jint nMethods) {
1667   int status = env->RegisterNatives(clazz, methods, nMethods);
1668   if (status < 0 || env->ExceptionOccurred()) {
1669     if (PrintMiscellaneous && (Verbose || WizardMode)) {
1670       tty->print_cr("Unsafe:  failed registering %s", message);
1671     }
1672     env->ExceptionClear();
1673     return false;
1674   } else {
1675     if (PrintMiscellaneous && (Verbose || WizardMode)) {
1676       tty->print_cr("Unsafe:  successfully registered %s", message);
1677     }
1678     return true;
1679   }
1680 }
1681 
1682 
1683 // This one function is exported, used by NativeLookup.
1684 // The Unsafe_xxx functions above are called only from the interpreter.
1685 // The optimizer looks at names and signatures to recognize
1686 // individual functions.
1687 
1688 JVM_ENTRY(void, JVM_RegisterUnsafeMethods(JNIEnv *env, jclass unsafecls))
1689   UnsafeWrapper("JVM_RegisterUnsafeMethods");
1690   {
1691     ThreadToNativeFromVM ttnfv(thread);
1692 
1693     // Unsafe methods
1694     {
1695       bool success = false;
1696       // We need to register the 1.6 methods first because the 1.8 methods would register fine on 1.7 and 1.6
1697       if (!success) {
1698         success = register_natives("1.6 methods",   env, unsafecls, methods_16,  sizeof(methods_16)/sizeof(JNINativeMethod));
1699       }
1700       if (!success) {
1701         success = register_natives("1.8 methods",   env, unsafecls, methods_18,  sizeof(methods_18)/sizeof(JNINativeMethod));
1702       }
1703       if (!success) {
1704         success = register_natives("1.5 methods",   env, unsafecls, methods_15,  sizeof(methods_15)/sizeof(JNINativeMethod));
1705       }
1706       if (!success) {
1707         success = register_natives("1.4.1 methods", env, unsafecls, methods_141, sizeof(methods_141)/sizeof(JNINativeMethod));
1708       }
1709       if (!success) {
1710         success = register_natives("1.4.0 methods", env, unsafecls, methods_140, sizeof(methods_140)/sizeof(JNINativeMethod));
1711       }
1712       guarantee(success, "register unsafe natives");
1713     }
1714 
1715     // Unsafe.getLoadAverage
1716     register_natives("1.6 loadavg method", env, unsafecls, loadavg_method, sizeof(loadavg_method)/sizeof(JNINativeMethod));
1717 
1718     // Prefetch methods
1719     register_natives("1.6 prefetch methods", env, unsafecls, prefetch_methods, sizeof(prefetch_methods)/sizeof(JNINativeMethod));
1720 
1721     // Memory copy methods
1722     {
1723       bool success = false;
1724       if (!success) {
1725         success = register_natives("1.7 memory copy methods", env, unsafecls, memcopy_methods_17, sizeof(memcopy_methods_17)/sizeof(JNINativeMethod));
1726       }
1727       if (!success) {
1728         success = register_natives("1.5 memory copy methods", env, unsafecls, memcopy_methods_15, sizeof(memcopy_methods_15)/sizeof(JNINativeMethod));
1729       }
1730     }
1731 
1732     // Unsafe.defineAnonymousClass
1733     if (EnableInvokeDynamic) {
1734       register_natives("1.7 define anonymous class method", env, unsafecls, anonk_methods, sizeof(anonk_methods)/sizeof(JNINativeMethod));
1735     }
1736 
1737     // Unsafe.shouldBeInitialized
1738     if (EnableInvokeDynamic) {
1739       register_natives("1.7 LambdaForm support", env, unsafecls, lform_methods, sizeof(lform_methods)/sizeof(JNINativeMethod));
1740     }
1741 
1742     // Fence methods
1743     register_natives("1.8 fence methods", env, unsafecls, fence_methods, sizeof(fence_methods)/sizeof(JNINativeMethod));
1744   }
1745 JVM_END