src/share/vm/prims/unsafe.cpp

Mon, 03 Jun 2019 16:14:54 +0100

author
xliu
date
Mon, 03 Jun 2019 16:14:54 +0100
changeset 9689
89dcef434423
parent 9327
f96fcd9e1e1b
child 9448
73d689add964
child 9858
b985cbb00e68
permissions
-rw-r--r--

8059575: JEP-JDK-8043304: Test task: Tiered Compilation level transition tests
Summary: Includes compile_id addition from JDK-8054492
Reviewed-by: andrew

     1 /*
     2  * Copyright (c) 2000, 2016, 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  */
    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/prefetch.inline.hpp"
    37 #include "runtime/orderAccess.inline.hpp"
    38 #include "runtime/reflection.hpp"
    39 #include "runtime/synchronizer.hpp"
    40 #include "services/threadService.hpp"
    41 #include "trace/tracing.hpp"
    42 #include "utilities/copy.hpp"
    43 #include "utilities/dtrace.hpp"
    45 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
    47 /*
    48  *      Implementation of class sun.misc.Unsafe
    49  */
    51 #ifndef USDT2
    52 HS_DTRACE_PROBE_DECL3(hotspot, thread__park__begin, uintptr_t, int, long long);
    53 HS_DTRACE_PROBE_DECL1(hotspot, thread__park__end, uintptr_t);
    54 HS_DTRACE_PROBE_DECL1(hotspot, thread__unpark, uintptr_t);
    55 #endif /* !USDT2 */
    57 #define MAX_OBJECT_SIZE \
    58   ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
    59     + ((julong)max_jint * sizeof(double)) )
    62 #define UNSAFE_ENTRY(result_type, header) \
    63   JVM_ENTRY(result_type, header)
    65 // Can't use UNSAFE_LEAF because it has the signature of a straight
    66 // call into the runtime (just like JVM_LEAF, funny that) but it's
    67 // called like a Java Native and thus the wrapper built for it passes
    68 // arguments like a JNI call.  It expects those arguments to be popped
    69 // from the stack on Intel like all good JNI args are, and adjusts the
    70 // stack according.  Since the JVM_LEAF call expects no extra
    71 // arguments the stack isn't popped in the C code, is pushed by the
    72 // wrapper and we get sick.
    73 //#define UNSAFE_LEAF(result_type, header) \
    74 //  JVM_LEAF(result_type, header)
    76 #define UNSAFE_END JVM_END
    78 #define UnsafeWrapper(arg) /*nothing, for the present*/
    81 inline void* addr_from_java(jlong addr) {
    82   // This assert fails in a variety of ways on 32-bit systems.
    83   // It is impossible to predict whether native code that converts
    84   // pointers to longs will sign-extend or zero-extend the addresses.
    85   //assert(addr == (uintptr_t)addr, "must not be odd high bits");
    86   return (void*)(uintptr_t)addr;
    87 }
    89 inline jlong addr_to_java(void* p) {
    90   assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
    91   return (uintptr_t)p;
    92 }
    95 // Note: The VM's obj_field and related accessors use byte-scaled
    96 // ("unscaled") offsets, just as the unsafe methods do.
    98 // However, the method Unsafe.fieldOffset explicitly declines to
    99 // guarantee this.  The field offset values manipulated by the Java user
   100 // through the Unsafe API are opaque cookies that just happen to be byte
   101 // offsets.  We represent this state of affairs by passing the cookies
   102 // through conversion functions when going between the VM and the Unsafe API.
   103 // The conversion functions just happen to be no-ops at present.
   105 inline jlong field_offset_to_byte_offset(jlong field_offset) {
   106   return field_offset;
   107 }
   109 inline jlong field_offset_from_byte_offset(jlong byte_offset) {
   110   return byte_offset;
   111 }
   113 inline jint invocation_key_from_method_slot(jint slot) {
   114   return slot;
   115 }
   117 inline jint invocation_key_to_method_slot(jint key) {
   118   return key;
   119 }
   121 inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
   122   jlong byte_offset = field_offset_to_byte_offset(field_offset);
   123 #ifdef ASSERT
   124   if (p != NULL) {
   125     assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
   126     if (byte_offset == (jint)byte_offset) {
   127       void* ptr_plus_disp = (address)p + byte_offset;
   128       assert((void*)p->obj_field_addr<oop>((jint)byte_offset) == ptr_plus_disp,
   129              "raw [ptr+disp] must be consistent with oop::field_base");
   130     }
   131     jlong p_size = HeapWordSize * (jlong)(p->size());
   132     assert(byte_offset < p_size, err_msg("Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, byte_offset, p_size));
   133   }
   134 #endif
   135   if (sizeof(char*) == sizeof(jint))    // (this constant folds!)
   136     return (address)p + (jint) byte_offset;
   137   else
   138     return (address)p +        byte_offset;
   139 }
   141 // Externally callable versions:
   142 // (Use these in compiler intrinsics which emulate unsafe primitives.)
   143 jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
   144   return field_offset;
   145 }
   146 jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
   147   return byte_offset;
   148 }
   149 jint Unsafe_invocation_key_from_method_slot(jint slot) {
   150   return invocation_key_from_method_slot(slot);
   151 }
   152 jint Unsafe_invocation_key_to_method_slot(jint key) {
   153   return invocation_key_to_method_slot(key);
   154 }
   157 ///// Data in the Java heap.
   159 #define truncate_jboolean(x) ((x) & 1)
   160 #define truncate_jbyte(x) (x)
   161 #define truncate_jshort(x) (x)
   162 #define truncate_jchar(x) (x)
   163 #define truncate_jint(x) (x)
   164 #define truncate_jlong(x) (x)
   165 #define truncate_jfloat(x) (x)
   166 #define truncate_jdouble(x) (x)
   168 #define GET_FIELD(obj, offset, type_name, v) \
   169   oop p = JNIHandles::resolve(obj); \
   170   type_name v = *(type_name*)index_oop_from_field_offset_long(p, offset)
   172 #define SET_FIELD(obj, offset, type_name, x) \
   173   oop p = JNIHandles::resolve(obj); \
   174   *(type_name*)index_oop_from_field_offset_long(p, offset) = truncate_##type_name(x)
   176 #define GET_FIELD_VOLATILE(obj, offset, type_name, v) \
   177   oop p = JNIHandles::resolve(obj); \
   178   if (support_IRIW_for_not_multiple_copy_atomic_cpu) { \
   179     OrderAccess::fence(); \
   180   } \
   181   volatile type_name v = OrderAccess::load_acquire((volatile type_name*)index_oop_from_field_offset_long(p, offset));
   183 #define SET_FIELD_VOLATILE(obj, offset, type_name, x) \
   184   oop p = JNIHandles::resolve(obj); \
   185   OrderAccess::release_store_fence((volatile type_name*)index_oop_from_field_offset_long(p, offset), truncate_##type_name(x));
   187 // Macros for oops that check UseCompressedOops
   189 #define GET_OOP_FIELD(obj, offset, v) \
   190   oop p = JNIHandles::resolve(obj);   \
   191   oop v;                              \
   192   if (UseCompressedOops) {            \
   193     narrowOop n = *(narrowOop*)index_oop_from_field_offset_long(p, offset); \
   194     v = oopDesc::decode_heap_oop(n);                                \
   195   } else {                            \
   196     v = *(oop*)index_oop_from_field_offset_long(p, offset);                 \
   197   }
   200 // Get/SetObject must be special-cased, since it works with handles.
   202 // We could be accessing the referent field in a reference
   203 // object. If G1 is enabled then we need to register non-null
   204 // referent with the SATB barrier.
   206 #if INCLUDE_ALL_GCS
   207 static bool is_java_lang_ref_Reference_access(oop o, jlong offset) {
   208   if (offset == java_lang_ref_Reference::referent_offset && o != NULL) {
   209     Klass* k = o->klass();
   210     if (InstanceKlass::cast(k)->reference_type() != REF_NONE) {
   211       assert(InstanceKlass::cast(k)->is_subclass_of(SystemDictionary::Reference_klass()), "sanity");
   212       return true;
   213     }
   214   }
   215  return false;
   216 }
   217 #endif
   219 static void ensure_satb_referent_alive(oop o, jlong offset, oop v) {
   220 #if INCLUDE_ALL_GCS
   221   if (UseG1GC && v != NULL && is_java_lang_ref_Reference_access(o, offset)) {
   222     G1SATBCardTableModRefBS::enqueue(v);
   223   }
   224 #endif
   225 }
   227 // The xxx140 variants for backward compatibility do not allow a full-width offset.
   228 UNSAFE_ENTRY(jobject, Unsafe_GetObject140(JNIEnv *env, jobject unsafe, jobject obj, jint offset))
   229   UnsafeWrapper("Unsafe_GetObject");
   230   if (obj == NULL)  THROW_0(vmSymbols::java_lang_NullPointerException());
   231   GET_OOP_FIELD(obj, offset, v)
   233   ensure_satb_referent_alive(p, offset, v);
   235   return JNIHandles::make_local(env, v);
   236 UNSAFE_END
   238 UNSAFE_ENTRY(void, Unsafe_SetObject140(JNIEnv *env, jobject unsafe, jobject obj, jint offset, jobject x_h))
   239   UnsafeWrapper("Unsafe_SetObject");
   240   if (obj == NULL)  THROW(vmSymbols::java_lang_NullPointerException());
   241   oop x = JNIHandles::resolve(x_h);
   242   //SET_FIELD(obj, offset, oop, x);
   243   oop p = JNIHandles::resolve(obj);
   244   if (UseCompressedOops) {
   245     if (x != NULL) {
   246       // If there is a heap base pointer, we are obliged to emit a store barrier.
   247       oop_store((narrowOop*)index_oop_from_field_offset_long(p, offset), x);
   248     } else {
   249       narrowOop n = oopDesc::encode_heap_oop_not_null(x);
   250       *(narrowOop*)index_oop_from_field_offset_long(p, offset) = n;
   251     }
   252   } else {
   253     if (x != NULL) {
   254       // If there is a heap base pointer, we are obliged to emit a store barrier.
   255       oop_store((oop*)index_oop_from_field_offset_long(p, offset), x);
   256     } else {
   257       *(oop*)index_oop_from_field_offset_long(p, offset) = x;
   258     }
   259   }
   260 UNSAFE_END
   262 // The normal variants allow a null base pointer with an arbitrary address.
   263 // But if the base pointer is non-null, the offset should make some sense.
   264 // That is, it should be in the range [0, MAX_OBJECT_SIZE].
   265 UNSAFE_ENTRY(jobject, Unsafe_GetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset))
   266   UnsafeWrapper("Unsafe_GetObject");
   267   GET_OOP_FIELD(obj, offset, v)
   269   ensure_satb_referent_alive(p, offset, v);
   271   return JNIHandles::make_local(env, v);
   272 UNSAFE_END
   274 UNSAFE_ENTRY(void, Unsafe_SetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h))
   275   UnsafeWrapper("Unsafe_SetObject");
   276   oop x = JNIHandles::resolve(x_h);
   277   oop p = JNIHandles::resolve(obj);
   278   if (UseCompressedOops) {
   279     oop_store((narrowOop*)index_oop_from_field_offset_long(p, offset), x);
   280   } else {
   281     oop_store((oop*)index_oop_from_field_offset_long(p, offset), x);
   282   }
   283 UNSAFE_END
   285 UNSAFE_ENTRY(jobject, Unsafe_GetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset))
   286   UnsafeWrapper("Unsafe_GetObjectVolatile");
   287   oop p = JNIHandles::resolve(obj);
   288   void* addr = index_oop_from_field_offset_long(p, offset);
   289   volatile oop v;
   290   if (UseCompressedOops) {
   291     volatile narrowOop n = *(volatile narrowOop*) addr;
   292     (void)const_cast<oop&>(v = oopDesc::decode_heap_oop(n));
   293   } else {
   294     (void)const_cast<oop&>(v = *(volatile oop*) addr);
   295   }
   297   ensure_satb_referent_alive(p, offset, v);
   299   OrderAccess::acquire();
   300   return JNIHandles::make_local(env, v);
   301 UNSAFE_END
   303 UNSAFE_ENTRY(void, Unsafe_SetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h))
   304   UnsafeWrapper("Unsafe_SetObjectVolatile");
   305   oop x = JNIHandles::resolve(x_h);
   306   oop p = JNIHandles::resolve(obj);
   307   void* addr = index_oop_from_field_offset_long(p, offset);
   308   OrderAccess::release();
   309   if (UseCompressedOops) {
   310     oop_store((narrowOop*)addr, x);
   311   } else {
   312     oop_store((oop*)addr, x);
   313   }
   314   OrderAccess::fence();
   315 UNSAFE_END
   317 #ifndef SUPPORTS_NATIVE_CX8
   319 // VM_Version::supports_cx8() is a surrogate for 'supports atomic long memory ops'.
   320 //
   321 // On platforms which do not support atomic compare-and-swap of jlong (8 byte)
   322 // values we have to use a lock-based scheme to enforce atomicity. This has to be
   323 // applied to all Unsafe operations that set the value of a jlong field. Even so
   324 // the compareAndSwapLong operation will not be atomic with respect to direct stores
   325 // to the field from Java code. It is important therefore that any Java code that
   326 // utilizes these Unsafe jlong operations does not perform direct stores. To permit
   327 // direct loads of the field from Java code we must also use Atomic::store within the
   328 // locked regions. And for good measure, in case there are direct stores, we also
   329 // employ Atomic::load within those regions. Note that the field in question must be
   330 // volatile and so must have atomic load/store accesses applied at the Java level.
   331 //
   332 // The locking scheme could utilize a range of strategies for controlling the locking
   333 // granularity: from a lock per-field through to a single global lock. The latter is
   334 // the simplest and is used for the current implementation. Note that the Java object
   335 // that contains the field, can not, in general, be used for locking. To do so can lead
   336 // to deadlocks as we may introduce locking into what appears to the Java code to be a
   337 // lock-free path.
   338 //
   339 // As all the locked-regions are very short and themselves non-blocking we can treat
   340 // them as leaf routines and elide safepoint checks (ie we don't perform any thread
   341 // state transitions even when blocking for the lock). Note that if we do choose to
   342 // add safepoint checks and thread state transitions, we must ensure that we calculate
   343 // the address of the field _after_ we have acquired the lock, else the object may have
   344 // been moved by the GC
   346 UNSAFE_ENTRY(jlong, Unsafe_GetLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset))
   347   UnsafeWrapper("Unsafe_GetLongVolatile");
   348   {
   349     if (VM_Version::supports_cx8()) {
   350       GET_FIELD_VOLATILE(obj, offset, jlong, v);
   351       return v;
   352     }
   353     else {
   354       Handle p (THREAD, JNIHandles::resolve(obj));
   355       jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
   356       MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
   357       jlong value = Atomic::load(addr);
   358       return value;
   359     }
   360   }
   361 UNSAFE_END
   363 UNSAFE_ENTRY(void, Unsafe_SetLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong x))
   364   UnsafeWrapper("Unsafe_SetLongVolatile");
   365   {
   366     if (VM_Version::supports_cx8()) {
   367       SET_FIELD_VOLATILE(obj, offset, jlong, x);
   368     }
   369     else {
   370       Handle p (THREAD, JNIHandles::resolve(obj));
   371       jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
   372       MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
   373       Atomic::store(x, addr);
   374     }
   375   }
   376 UNSAFE_END
   378 #endif // not SUPPORTS_NATIVE_CX8
   380 #define DEFINE_GETSETOOP(jboolean, Boolean) \
   381  \
   382 UNSAFE_ENTRY(jboolean, Unsafe_Get##Boolean##140(JNIEnv *env, jobject unsafe, jobject obj, jint offset)) \
   383   UnsafeWrapper("Unsafe_Get"#Boolean); \
   384   if (obj == NULL)  THROW_0(vmSymbols::java_lang_NullPointerException()); \
   385   GET_FIELD(obj, offset, jboolean, v); \
   386   return v; \
   387 UNSAFE_END \
   388  \
   389 UNSAFE_ENTRY(void, Unsafe_Set##Boolean##140(JNIEnv *env, jobject unsafe, jobject obj, jint offset, jboolean x)) \
   390   UnsafeWrapper("Unsafe_Set"#Boolean); \
   391   if (obj == NULL)  THROW(vmSymbols::java_lang_NullPointerException()); \
   392   SET_FIELD(obj, offset, jboolean, x); \
   393 UNSAFE_END \
   394  \
   395 UNSAFE_ENTRY(jboolean, Unsafe_Get##Boolean(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) \
   396   UnsafeWrapper("Unsafe_Get"#Boolean); \
   397   GET_FIELD(obj, offset, jboolean, v); \
   398   return v; \
   399 UNSAFE_END \
   400  \
   401 UNSAFE_ENTRY(void, Unsafe_Set##Boolean(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jboolean x)) \
   402   UnsafeWrapper("Unsafe_Set"#Boolean); \
   403   SET_FIELD(obj, offset, jboolean, x); \
   404 UNSAFE_END \
   405  \
   406 // END DEFINE_GETSETOOP.
   408 DEFINE_GETSETOOP(jboolean, Boolean)
   409 DEFINE_GETSETOOP(jbyte, Byte)
   410 DEFINE_GETSETOOP(jshort, Short);
   411 DEFINE_GETSETOOP(jchar, Char);
   412 DEFINE_GETSETOOP(jint, Int);
   413 DEFINE_GETSETOOP(jlong, Long);
   414 DEFINE_GETSETOOP(jfloat, Float);
   415 DEFINE_GETSETOOP(jdouble, Double);
   417 #undef DEFINE_GETSETOOP
   419 #define DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean) \
   420  \
   421 UNSAFE_ENTRY(jboolean, Unsafe_Get##Boolean##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) \
   422   UnsafeWrapper("Unsafe_Get"#Boolean); \
   423   GET_FIELD_VOLATILE(obj, offset, jboolean, v); \
   424   return v; \
   425 UNSAFE_END \
   426  \
   427 UNSAFE_ENTRY(void, Unsafe_Set##Boolean##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jboolean x)) \
   428   UnsafeWrapper("Unsafe_Set"#Boolean); \
   429   SET_FIELD_VOLATILE(obj, offset, jboolean, x); \
   430 UNSAFE_END \
   431  \
   432 // END DEFINE_GETSETOOP_VOLATILE.
   434 DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
   435 DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
   436 DEFINE_GETSETOOP_VOLATILE(jshort, Short);
   437 DEFINE_GETSETOOP_VOLATILE(jchar, Char);
   438 DEFINE_GETSETOOP_VOLATILE(jint, Int);
   439 DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
   440 DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
   442 #ifdef SUPPORTS_NATIVE_CX8
   443 DEFINE_GETSETOOP_VOLATILE(jlong, Long);
   444 #endif
   446 #undef DEFINE_GETSETOOP_VOLATILE
   448 // The non-intrinsified versions of setOrdered just use setVolatile
   450 UNSAFE_ENTRY(void, Unsafe_SetOrderedInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint x))
   451   UnsafeWrapper("Unsafe_SetOrderedInt");
   452   SET_FIELD_VOLATILE(obj, offset, jint, x);
   453 UNSAFE_END
   455 UNSAFE_ENTRY(void, Unsafe_SetOrderedObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h))
   456   UnsafeWrapper("Unsafe_SetOrderedObject");
   457   oop x = JNIHandles::resolve(x_h);
   458   oop p = JNIHandles::resolve(obj);
   459   void* addr = index_oop_from_field_offset_long(p, offset);
   460   OrderAccess::release();
   461   if (UseCompressedOops) {
   462     oop_store((narrowOop*)addr, x);
   463   } else {
   464     oop_store((oop*)addr, x);
   465   }
   466   OrderAccess::fence();
   467 UNSAFE_END
   469 UNSAFE_ENTRY(void, Unsafe_SetOrderedLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong x))
   470   UnsafeWrapper("Unsafe_SetOrderedLong");
   471 #ifdef SUPPORTS_NATIVE_CX8
   472   SET_FIELD_VOLATILE(obj, offset, jlong, x);
   473 #else
   474   // Keep old code for platforms which may not have atomic long (8 bytes) instructions
   475   {
   476     if (VM_Version::supports_cx8()) {
   477       SET_FIELD_VOLATILE(obj, offset, jlong, x);
   478     }
   479     else {
   480       Handle p (THREAD, JNIHandles::resolve(obj));
   481       jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
   482       MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
   483       Atomic::store(x, addr);
   484     }
   485   }
   486 #endif
   487 UNSAFE_END
   489 UNSAFE_ENTRY(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe))
   490   UnsafeWrapper("Unsafe_LoadFence");
   491   OrderAccess::acquire();
   492 UNSAFE_END
   494 UNSAFE_ENTRY(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe))
   495   UnsafeWrapper("Unsafe_StoreFence");
   496   OrderAccess::release();
   497 UNSAFE_END
   499 UNSAFE_ENTRY(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe))
   500   UnsafeWrapper("Unsafe_FullFence");
   501   OrderAccess::fence();
   502 UNSAFE_END
   504 ////// Data in the C heap.
   506 // Note:  These do not throw NullPointerException for bad pointers.
   507 // They just crash.  Only a oop base pointer can generate a NullPointerException.
   508 //
   509 #define DEFINE_GETSETNATIVE(java_type, Type, native_type) \
   510  \
   511 UNSAFE_ENTRY(java_type, Unsafe_GetNative##Type(JNIEnv *env, jobject unsafe, jlong addr)) \
   512   UnsafeWrapper("Unsafe_GetNative"#Type); \
   513   void* p = addr_from_java(addr); \
   514   JavaThread* t = JavaThread::current(); \
   515   t->set_doing_unsafe_access(true); \
   516   java_type x = *(volatile native_type*)p; \
   517   t->set_doing_unsafe_access(false); \
   518   return x; \
   519 UNSAFE_END \
   520  \
   521 UNSAFE_ENTRY(void, Unsafe_SetNative##Type(JNIEnv *env, jobject unsafe, jlong addr, java_type x)) \
   522   UnsafeWrapper("Unsafe_SetNative"#Type); \
   523   JavaThread* t = JavaThread::current(); \
   524   t->set_doing_unsafe_access(true); \
   525   void* p = addr_from_java(addr); \
   526   *(volatile native_type*)p = x; \
   527   t->set_doing_unsafe_access(false); \
   528 UNSAFE_END \
   529  \
   530 // END DEFINE_GETSETNATIVE.
   532 DEFINE_GETSETNATIVE(jbyte, Byte, signed char)
   533 DEFINE_GETSETNATIVE(jshort, Short, signed short);
   534 DEFINE_GETSETNATIVE(jchar, Char, unsigned short);
   535 DEFINE_GETSETNATIVE(jint, Int, jint);
   536 // no long -- handled specially
   537 DEFINE_GETSETNATIVE(jfloat, Float, float);
   538 DEFINE_GETSETNATIVE(jdouble, Double, double);
   540 #undef DEFINE_GETSETNATIVE
   542 UNSAFE_ENTRY(jlong, Unsafe_GetNativeLong(JNIEnv *env, jobject unsafe, jlong addr))
   543   UnsafeWrapper("Unsafe_GetNativeLong");
   544   JavaThread* t = JavaThread::current();
   545   // We do it this way to avoid problems with access to heap using 64
   546   // bit loads, as jlong in heap could be not 64-bit aligned, and on
   547   // some CPUs (SPARC) it leads to SIGBUS.
   548   t->set_doing_unsafe_access(true);
   549   void* p = addr_from_java(addr);
   550   jlong x;
   551   if (((intptr_t)p & 7) == 0) {
   552     // jlong is aligned, do a volatile access
   553     x = *(volatile jlong*)p;
   554   } else {
   555     jlong_accessor acc;
   556     acc.words[0] = ((volatile jint*)p)[0];
   557     acc.words[1] = ((volatile jint*)p)[1];
   558     x = acc.long_value;
   559   }
   560   t->set_doing_unsafe_access(false);
   561   return x;
   562 UNSAFE_END
   564 UNSAFE_ENTRY(void, Unsafe_SetNativeLong(JNIEnv *env, jobject unsafe, jlong addr, jlong x))
   565   UnsafeWrapper("Unsafe_SetNativeLong");
   566   JavaThread* t = JavaThread::current();
   567   // see comment for Unsafe_GetNativeLong
   568   t->set_doing_unsafe_access(true);
   569   void* p = addr_from_java(addr);
   570   if (((intptr_t)p & 7) == 0) {
   571     // jlong is aligned, do a volatile access
   572     *(volatile jlong*)p = x;
   573   } else {
   574     jlong_accessor acc;
   575     acc.long_value = x;
   576     ((volatile jint*)p)[0] = acc.words[0];
   577     ((volatile jint*)p)[1] = acc.words[1];
   578   }
   579   t->set_doing_unsafe_access(false);
   580 UNSAFE_END
   583 UNSAFE_ENTRY(jlong, Unsafe_GetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr))
   584   UnsafeWrapper("Unsafe_GetNativeAddress");
   585   void* p = addr_from_java(addr);
   586   return addr_to_java(*(void**)p);
   587 UNSAFE_END
   589 UNSAFE_ENTRY(void, Unsafe_SetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr, jlong x))
   590   UnsafeWrapper("Unsafe_SetNativeAddress");
   591   void* p = addr_from_java(addr);
   592   *(void**)p = addr_from_java(x);
   593 UNSAFE_END
   596 ////// Allocation requests
   598 UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls))
   599   UnsafeWrapper("Unsafe_AllocateInstance");
   600   {
   601     ThreadToNativeFromVM ttnfv(thread);
   602     return env->AllocObject(cls);
   603   }
   604 UNSAFE_END
   606 UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory(JNIEnv *env, jobject unsafe, jlong size))
   607   UnsafeWrapper("Unsafe_AllocateMemory");
   608   size_t sz = (size_t)size;
   609   if (sz != (julong)size || size < 0) {
   610     THROW_0(vmSymbols::java_lang_IllegalArgumentException());
   611   }
   612   if (sz == 0) {
   613     return 0;
   614   }
   615   sz = round_to(sz, HeapWordSize);
   616   void* x = os::malloc(sz, mtInternal);
   617   if (x == NULL) {
   618     THROW_0(vmSymbols::java_lang_OutOfMemoryError());
   619   }
   620   //Copy::fill_to_words((HeapWord*)x, sz / HeapWordSize);
   621   return addr_to_java(x);
   622 UNSAFE_END
   624 UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory(JNIEnv *env, jobject unsafe, jlong addr, jlong size))
   625   UnsafeWrapper("Unsafe_ReallocateMemory");
   626   void* p = addr_from_java(addr);
   627   size_t sz = (size_t)size;
   628   if (sz != (julong)size || size < 0) {
   629     THROW_0(vmSymbols::java_lang_IllegalArgumentException());
   630   }
   631   if (sz == 0) {
   632     os::free(p);
   633     return 0;
   634   }
   635   sz = round_to(sz, HeapWordSize);
   636   void* x = (p == NULL) ? os::malloc(sz, mtInternal) : os::realloc(p, sz, mtInternal);
   637   if (x == NULL) {
   638     THROW_0(vmSymbols::java_lang_OutOfMemoryError());
   639   }
   640   return addr_to_java(x);
   641 UNSAFE_END
   643 UNSAFE_ENTRY(void, Unsafe_FreeMemory(JNIEnv *env, jobject unsafe, jlong addr))
   644   UnsafeWrapper("Unsafe_FreeMemory");
   645   void* p = addr_from_java(addr);
   646   if (p == NULL) {
   647     return;
   648   }
   649   os::free(p);
   650 UNSAFE_END
   652 UNSAFE_ENTRY(void, Unsafe_SetMemory(JNIEnv *env, jobject unsafe, jlong addr, jlong size, jbyte value))
   653   UnsafeWrapper("Unsafe_SetMemory");
   654   size_t sz = (size_t)size;
   655   if (sz != (julong)size || size < 0) {
   656     THROW(vmSymbols::java_lang_IllegalArgumentException());
   657   }
   658   char* p = (char*) addr_from_java(addr);
   659   Copy::fill_to_memory_atomic(p, sz, value);
   660 UNSAFE_END
   662 UNSAFE_ENTRY(void, Unsafe_SetMemory2(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value))
   663   UnsafeWrapper("Unsafe_SetMemory");
   664   size_t sz = (size_t)size;
   665   if (sz != (julong)size || size < 0) {
   666     THROW(vmSymbols::java_lang_IllegalArgumentException());
   667   }
   668   oop base = JNIHandles::resolve(obj);
   669   void* p = index_oop_from_field_offset_long(base, offset);
   670   Copy::fill_to_memory_atomic(p, sz, value);
   671 UNSAFE_END
   673 UNSAFE_ENTRY(void, Unsafe_CopyMemory(JNIEnv *env, jobject unsafe, jlong srcAddr, jlong dstAddr, jlong size))
   674   UnsafeWrapper("Unsafe_CopyMemory");
   675   if (size == 0) {
   676     return;
   677   }
   678   size_t sz = (size_t)size;
   679   if (sz != (julong)size || size < 0) {
   680     THROW(vmSymbols::java_lang_IllegalArgumentException());
   681   }
   682   void* src = addr_from_java(srcAddr);
   683   void* dst = addr_from_java(dstAddr);
   684   Copy::conjoint_memory_atomic(src, dst, sz);
   685 UNSAFE_END
   687 UNSAFE_ENTRY(void, Unsafe_CopyMemory2(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size))
   688   UnsafeWrapper("Unsafe_CopyMemory");
   689   if (size == 0) {
   690     return;
   691   }
   692   size_t sz = (size_t)size;
   693   if (sz != (julong)size || size < 0) {
   694     THROW(vmSymbols::java_lang_IllegalArgumentException());
   695   }
   696   oop srcp = JNIHandles::resolve(srcObj);
   697   oop dstp = JNIHandles::resolve(dstObj);
   698   if (dstp != NULL && !dstp->is_typeArray()) {
   699     // NYI:  This works only for non-oop arrays at present.
   700     // Generalizing it would be reasonable, but requires card marking.
   701     // Also, autoboxing a Long from 0L in copyMemory(x,y, 0L,z, n) would be bad.
   702     THROW(vmSymbols::java_lang_IllegalArgumentException());
   703   }
   704   void* src = index_oop_from_field_offset_long(srcp, srcOffset);
   705   void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
   706   Copy::conjoint_memory_atomic(src, dst, sz);
   707 UNSAFE_END
   710 ////// Random queries
   712 // See comment at file start about UNSAFE_LEAF
   713 //UNSAFE_LEAF(jint, Unsafe_AddressSize())
   714 UNSAFE_ENTRY(jint, Unsafe_AddressSize(JNIEnv *env, jobject unsafe))
   715   UnsafeWrapper("Unsafe_AddressSize");
   716   return sizeof(void*);
   717 UNSAFE_END
   719 // See comment at file start about UNSAFE_LEAF
   720 //UNSAFE_LEAF(jint, Unsafe_PageSize())
   721 UNSAFE_ENTRY(jint, Unsafe_PageSize(JNIEnv *env, jobject unsafe))
   722   UnsafeWrapper("Unsafe_PageSize");
   723   return os::vm_page_size();
   724 UNSAFE_END
   726 jint find_field_offset(jobject field, int must_be_static, TRAPS) {
   727   if (field == NULL) {
   728     THROW_0(vmSymbols::java_lang_NullPointerException());
   729   }
   731   oop reflected   = JNIHandles::resolve_non_null(field);
   732   oop mirror      = java_lang_reflect_Field::clazz(reflected);
   733   Klass* k      = java_lang_Class::as_Klass(mirror);
   734   int slot        = java_lang_reflect_Field::slot(reflected);
   735   int modifiers   = java_lang_reflect_Field::modifiers(reflected);
   737   if (must_be_static >= 0) {
   738     int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
   739     if (must_be_static != really_is_static) {
   740       THROW_0(vmSymbols::java_lang_IllegalArgumentException());
   741     }
   742   }
   744   int offset = InstanceKlass::cast(k)->field_offset(slot);
   745   return field_offset_from_byte_offset(offset);
   746 }
   748 UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset(JNIEnv *env, jobject unsafe, jobject field))
   749   UnsafeWrapper("Unsafe_ObjectFieldOffset");
   750   return find_field_offset(field, 0, THREAD);
   751 UNSAFE_END
   753 UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset(JNIEnv *env, jobject unsafe, jobject field))
   754   UnsafeWrapper("Unsafe_StaticFieldOffset");
   755   return find_field_offset(field, 1, THREAD);
   756 UNSAFE_END
   758 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBaseFromField(JNIEnv *env, jobject unsafe, jobject field))
   759   UnsafeWrapper("Unsafe_StaticFieldBase");
   760   // Note:  In this VM implementation, a field address is always a short
   761   // offset from the base of a a klass metaobject.  Thus, the full dynamic
   762   // range of the return type is never used.  However, some implementations
   763   // might put the static field inside an array shared by many classes,
   764   // or even at a fixed address, in which case the address could be quite
   765   // large.  In that last case, this function would return NULL, since
   766   // the address would operate alone, without any base pointer.
   768   if (field == NULL)  THROW_0(vmSymbols::java_lang_NullPointerException());
   770   oop reflected   = JNIHandles::resolve_non_null(field);
   771   oop mirror      = java_lang_reflect_Field::clazz(reflected);
   772   int modifiers   = java_lang_reflect_Field::modifiers(reflected);
   774   if ((modifiers & JVM_ACC_STATIC) == 0) {
   775     THROW_0(vmSymbols::java_lang_IllegalArgumentException());
   776   }
   778   return JNIHandles::make_local(env, mirror);
   779 UNSAFE_END
   781 //@deprecated
   782 UNSAFE_ENTRY(jint, Unsafe_FieldOffset(JNIEnv *env, jobject unsafe, jobject field))
   783   UnsafeWrapper("Unsafe_FieldOffset");
   784   // tries (but fails) to be polymorphic between static and non-static:
   785   jlong offset = find_field_offset(field, -1, THREAD);
   786   guarantee(offset == (jint)offset, "offset fits in 32 bits");
   787   return (jint)offset;
   788 UNSAFE_END
   790 //@deprecated
   791 UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBaseFromClass(JNIEnv *env, jobject unsafe, jobject clazz))
   792   UnsafeWrapper("Unsafe_StaticFieldBase");
   793   if (clazz == NULL) {
   794     THROW_0(vmSymbols::java_lang_NullPointerException());
   795   }
   796   return JNIHandles::make_local(env, JNIHandles::resolve_non_null(clazz));
   797 UNSAFE_END
   799 UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized(JNIEnv *env, jobject unsafe, jobject clazz)) {
   800   UnsafeWrapper("Unsafe_EnsureClassInitialized");
   801   if (clazz == NULL) {
   802     THROW(vmSymbols::java_lang_NullPointerException());
   803   }
   804   oop mirror = JNIHandles::resolve_non_null(clazz);
   806   Klass* klass = java_lang_Class::as_Klass(mirror);
   807   if (klass != NULL && klass->should_be_initialized()) {
   808     InstanceKlass* k = InstanceKlass::cast(klass);
   809     k->initialize(CHECK);
   810   }
   811 }
   812 UNSAFE_END
   814 UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized(JNIEnv *env, jobject unsafe, jobject clazz)) {
   815   UnsafeWrapper("Unsafe_ShouldBeInitialized");
   816   if (clazz == NULL) {
   817     THROW_(vmSymbols::java_lang_NullPointerException(), false);
   818   }
   819   oop mirror = JNIHandles::resolve_non_null(clazz);
   820   Klass* klass = java_lang_Class::as_Klass(mirror);
   821   if (klass != NULL && klass->should_be_initialized()) {
   822     return true;
   823   }
   824   return false;
   825 }
   826 UNSAFE_END
   828 static void getBaseAndScale(int& base, int& scale, jclass acls, TRAPS) {
   829   if (acls == NULL) {
   830     THROW(vmSymbols::java_lang_NullPointerException());
   831   }
   832   oop      mirror = JNIHandles::resolve_non_null(acls);
   833   Klass* k      = java_lang_Class::as_Klass(mirror);
   834   if (k == NULL || !k->oop_is_array()) {
   835     THROW(vmSymbols::java_lang_InvalidClassException());
   836   } else if (k->oop_is_objArray()) {
   837     base  = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
   838     scale = heapOopSize;
   839   } else if (k->oop_is_typeArray()) {
   840     TypeArrayKlass* tak = TypeArrayKlass::cast(k);
   841     base  = tak->array_header_in_bytes();
   842     assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
   843     scale = (1 << tak->log2_element_size());
   844   } else {
   845     ShouldNotReachHere();
   846   }
   847 }
   849 UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset(JNIEnv *env, jobject unsafe, jclass acls))
   850   UnsafeWrapper("Unsafe_ArrayBaseOffset");
   851   int base = 0, scale = 0;
   852   getBaseAndScale(base, scale, acls, CHECK_0);
   853   return field_offset_from_byte_offset(base);
   854 UNSAFE_END
   857 UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale(JNIEnv *env, jobject unsafe, jclass acls))
   858   UnsafeWrapper("Unsafe_ArrayIndexScale");
   859   int base = 0, scale = 0;
   860   getBaseAndScale(base, scale, acls, CHECK_0);
   861   // This VM packs both fields and array elements down to the byte.
   862   // But watch out:  If this changes, so that array references for
   863   // a given primitive type (say, T_BOOLEAN) use different memory units
   864   // than fields, this method MUST return zero for such arrays.
   865   // For example, the VM used to store sub-word sized fields in full
   866   // words in the object layout, so that accessors like getByte(Object,int)
   867   // did not really do what one might expect for arrays.  Therefore,
   868   // this function used to report a zero scale factor, so that the user
   869   // would know not to attempt to access sub-word array elements.
   870   // // Code for unpacked fields:
   871   // if (scale < wordSize)  return 0;
   873   // The following allows for a pretty general fieldOffset cookie scheme,
   874   // but requires it to be linear in byte offset.
   875   return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
   876 UNSAFE_END
   879 static inline void throw_new(JNIEnv *env, const char *ename) {
   880   char buf[100];
   881   strcpy(buf, "java/lang/");
   882   strcat(buf, ename);
   883   jclass cls = env->FindClass(buf);
   884   if (env->ExceptionCheck()) {
   885     env->ExceptionClear();
   886     tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", buf);
   887     return;
   888   }
   889   char* msg = NULL;
   890   env->ThrowNew(cls, msg);
   891 }
   893 static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
   894   {
   895     // Code lifted from JDK 1.3 ClassLoader.c
   897     jbyte *body;
   898     char *utfName;
   899     jclass result = 0;
   900     char buf[128];
   902     if (UsePerfData) {
   903       ClassLoader::unsafe_defineClassCallCounter()->inc();
   904     }
   906     if (data == NULL) {
   907         throw_new(env, "NullPointerException");
   908         return 0;
   909     }
   911     /* Work around 4153825. malloc crashes on Solaris when passed a
   912      * negative size.
   913      */
   914     if (length < 0) {
   915         throw_new(env, "ArrayIndexOutOfBoundsException");
   916         return 0;
   917     }
   919     body = NEW_C_HEAP_ARRAY(jbyte, length, mtInternal);
   921     if (body == 0) {
   922         throw_new(env, "OutOfMemoryError");
   923         return 0;
   924     }
   926     env->GetByteArrayRegion(data, offset, length, body);
   928     if (env->ExceptionOccurred())
   929         goto free_body;
   931     if (name != NULL) {
   932         uint len = env->GetStringUTFLength(name);
   933         int unicode_len = env->GetStringLength(name);
   934         if (len >= sizeof(buf)) {
   935             utfName = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
   936             if (utfName == NULL) {
   937                 throw_new(env, "OutOfMemoryError");
   938                 goto free_body;
   939             }
   940         } else {
   941             utfName = buf;
   942         }
   943         env->GetStringUTFRegion(name, 0, unicode_len, utfName);
   944         //VerifyFixClassname(utfName);
   945         for (uint i = 0; i < len; i++) {
   946           if (utfName[i] == '.')   utfName[i] = '/';
   947         }
   948     } else {
   949         utfName = NULL;
   950     }
   952     result = JVM_DefineClass(env, utfName, loader, body, length, pd);
   954     if (utfName && utfName != buf)
   955         FREE_C_HEAP_ARRAY(char, utfName, mtInternal);
   957  free_body:
   958     FREE_C_HEAP_ARRAY(jbyte, body, mtInternal);
   959     return result;
   960   }
   961 }
   964 UNSAFE_ENTRY(jclass, Unsafe_DefineClass(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd))
   965   UnsafeWrapper("Unsafe_DefineClass");
   966   {
   967     ThreadToNativeFromVM ttnfv(thread);
   968     return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
   969   }
   970 UNSAFE_END
   973 UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length))
   974   UnsafeWrapper("Unsafe_DefineClass");
   975   {
   976     ThreadToNativeFromVM ttnfv(thread);
   978     int depthFromDefineClass0 = 1;
   979     jclass  caller = JVM_GetCallerClass(env, depthFromDefineClass0);
   980     jobject loader = (caller == NULL) ? NULL : JVM_GetClassLoader(env, caller);
   981     jobject pd     = (caller == NULL) ? NULL : JVM_GetProtectionDomain(env, caller);
   983     return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
   984   }
   985 UNSAFE_END
   988 #define DAC_Args CLS"[B["OBJ
   989 // define a class but do not make it known to the class loader or system dictionary
   990 // - host_class:  supplies context for linkage, access control, protection domain, and class loader
   991 // - data:  bytes of a class file, a raw memory address (length gives the number of bytes)
   992 // - cp_patches:  where non-null entries exist, they replace corresponding CP entries in data
   994 // When you load an anonymous class U, it works as if you changed its name just before loading,
   995 // to a name that you will never use again.  Since the name is lost, no other class can directly
   996 // link to any member of U.  Just after U is loaded, the only way to use it is reflectively,
   997 // through java.lang.Class methods like Class.newInstance.
   999 // Access checks for linkage sites within U continue to follow the same rules as for named classes.
  1000 // The package of an anonymous class is given by the package qualifier on the name under which it was loaded.
  1001 // An anonymous class also has special privileges to access any member of its host class.
  1002 // This is the main reason why this loading operation is unsafe.  The purpose of this is to
  1003 // allow language implementations to simulate "open classes"; a host class in effect gets
  1004 // new code when an anonymous class is loaded alongside it.  A less convenient but more
  1005 // standard way to do this is with reflection, which can also be set to ignore access
  1006 // restrictions.
  1008 // Access into an anonymous class is possible only through reflection.  Therefore, there
  1009 // are no special access rules for calling into an anonymous class.  The relaxed access
  1010 // rule for the host class is applied in the opposite direction:  A host class reflectively
  1011 // access one of its anonymous classes.
  1013 // If you load the same bytecodes twice, you get two different classes.  You can reload
  1014 // the same bytecodes with or without varying CP patches.
  1016 // By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
  1017 // The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
  1018 // The CONSTANT_Class entry for that name can be patched to refer directly to U1.
  1020 // This allows, for example, U2 to use U1 as a superclass or super-interface, or as
  1021 // an outer class (so that U2 is an anonymous inner class of anonymous U1).
  1022 // It is not possible for a named class, or an older anonymous class, to refer by
  1023 // name (via its CP) to a newer anonymous class.
  1025 // CP patching may also be used to modify (i.e., hack) the names of methods, classes,
  1026 // or type descriptors used in the loaded anonymous class.
  1028 // Finally, CP patching may be used to introduce "live" objects into the constant pool,
  1029 // instead of "dead" strings.  A compiled statement like println((Object)"hello") can
  1030 // be changed to println(greeting), where greeting is an arbitrary object created before
  1031 // the anonymous class is loaded.  This is useful in dynamic languages, in which
  1032 // various kinds of metaobjects must be introduced as constants into bytecode.
  1033 // Note the cast (Object), which tells the verifier to expect an arbitrary object,
  1034 // not just a literal string.  For such ldc instructions, the verifier uses the
  1035 // type Object instead of String, if the loaded constant is not in fact a String.
  1037 static instanceKlassHandle
  1038 Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
  1039                                  jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
  1040                                  HeapWord* *temp_alloc,
  1041                                  TRAPS) {
  1043   if (UsePerfData) {
  1044     ClassLoader::unsafe_defineClassCallCounter()->inc();
  1047   if (data == NULL) {
  1048     THROW_0(vmSymbols::java_lang_NullPointerException());
  1051   jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
  1052   jint word_length = (length + sizeof(HeapWord)-1) / sizeof(HeapWord);
  1053   HeapWord* body = NEW_C_HEAP_ARRAY(HeapWord, word_length, mtInternal);
  1054   if (body == NULL) {
  1055     THROW_0(vmSymbols::java_lang_OutOfMemoryError());
  1058   // caller responsible to free it:
  1059   (*temp_alloc) = body;
  1062     jbyte* array_base = typeArrayOop(JNIHandles::resolve_non_null(data))->byte_at_addr(0);
  1063     Copy::conjoint_words((HeapWord*) array_base, body, word_length);
  1066   u1* class_bytes = (u1*) body;
  1067   int class_bytes_length = (int) length;
  1068   if (class_bytes_length < 0)  class_bytes_length = 0;
  1069   if (class_bytes == NULL
  1070       || host_class == NULL
  1071       || length != class_bytes_length)
  1072     THROW_0(vmSymbols::java_lang_IllegalArgumentException());
  1074   objArrayHandle cp_patches_h;
  1075   if (cp_patches_jh != NULL) {
  1076     oop p = JNIHandles::resolve_non_null(cp_patches_jh);
  1077     if (!p->is_objArray())
  1078       THROW_0(vmSymbols::java_lang_IllegalArgumentException());
  1079     cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
  1082   KlassHandle host_klass(THREAD, java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class)));
  1083   const char* host_source = host_klass->external_name();
  1084   Handle      host_loader(THREAD, host_klass->class_loader());
  1085   Handle      host_domain(THREAD, host_klass->protection_domain());
  1087   GrowableArray<Handle>* cp_patches = NULL;
  1088   if (cp_patches_h.not_null()) {
  1089     int alen = cp_patches_h->length();
  1090     for (int i = alen-1; i >= 0; i--) {
  1091       oop p = cp_patches_h->obj_at(i);
  1092       if (p != NULL) {
  1093         Handle patch(THREAD, p);
  1094         if (cp_patches == NULL)
  1095           cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
  1096         cp_patches->at_put(i, patch);
  1101   ClassFileStream st(class_bytes, class_bytes_length, (char*) host_source);
  1103   instanceKlassHandle anon_klass;
  1105     Symbol* no_class_name = NULL;
  1106     Klass* anonk = SystemDictionary::parse_stream(no_class_name,
  1107                                                     host_loader, host_domain,
  1108                                                     &st, host_klass, cp_patches,
  1109                                                     CHECK_NULL);
  1110     if (anonk == NULL)  return NULL;
  1111     anon_klass = instanceKlassHandle(THREAD, anonk);
  1114   return anon_klass;
  1117 UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh))
  1119   instanceKlassHandle anon_klass;
  1120   jobject res_jh = NULL;
  1122   UnsafeWrapper("Unsafe_DefineAnonymousClass");
  1123   ResourceMark rm(THREAD);
  1125   HeapWord* temp_alloc = NULL;
  1127   anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data,
  1128                                                 cp_patches_jh,
  1129                                                    &temp_alloc, THREAD);
  1130   if (anon_klass() != NULL)
  1131     res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
  1133   // try/finally clause:
  1134   if (temp_alloc != NULL) {
  1135     FREE_C_HEAP_ARRAY(HeapWord, temp_alloc, mtInternal);
  1138   // The anonymous class loader data has been artificially been kept alive to
  1139   // this point.   The mirror and any instances of this class have to keep
  1140   // it alive afterwards.
  1141   if (anon_klass() != NULL) {
  1142     anon_klass->class_loader_data()->set_keep_alive(false);
  1145   // let caller initialize it as needed...
  1147   return (jclass) res_jh;
  1149 UNSAFE_END
  1153 UNSAFE_ENTRY(void, Unsafe_MonitorEnter(JNIEnv *env, jobject unsafe, jobject jobj))
  1154   UnsafeWrapper("Unsafe_MonitorEnter");
  1156     if (jobj == NULL) {
  1157       THROW(vmSymbols::java_lang_NullPointerException());
  1159     Handle obj(thread, JNIHandles::resolve_non_null(jobj));
  1160     ObjectSynchronizer::jni_enter(obj, CHECK);
  1162 UNSAFE_END
  1165 UNSAFE_ENTRY(jboolean, Unsafe_TryMonitorEnter(JNIEnv *env, jobject unsafe, jobject jobj))
  1166   UnsafeWrapper("Unsafe_TryMonitorEnter");
  1168     if (jobj == NULL) {
  1169       THROW_(vmSymbols::java_lang_NullPointerException(), JNI_FALSE);
  1171     Handle obj(thread, JNIHandles::resolve_non_null(jobj));
  1172     bool res = ObjectSynchronizer::jni_try_enter(obj, CHECK_0);
  1173     return (res ? JNI_TRUE : JNI_FALSE);
  1175 UNSAFE_END
  1178 UNSAFE_ENTRY(void, Unsafe_MonitorExit(JNIEnv *env, jobject unsafe, jobject jobj))
  1179   UnsafeWrapper("Unsafe_MonitorExit");
  1181     if (jobj == NULL) {
  1182       THROW(vmSymbols::java_lang_NullPointerException());
  1184     Handle obj(THREAD, JNIHandles::resolve_non_null(jobj));
  1185     ObjectSynchronizer::jni_exit(obj(), CHECK);
  1187 UNSAFE_END
  1190 UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr))
  1191   UnsafeWrapper("Unsafe_ThrowException");
  1193     ThreadToNativeFromVM ttnfv(thread);
  1194     env->Throw(thr);
  1196 UNSAFE_END
  1198 // JSR166 ------------------------------------------------------------------
  1200 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h))
  1201   UnsafeWrapper("Unsafe_CompareAndSwapObject");
  1202   oop x = JNIHandles::resolve(x_h);
  1203   oop e = JNIHandles::resolve(e_h);
  1204   oop p = JNIHandles::resolve(obj);
  1205   HeapWord* addr = (HeapWord *)index_oop_from_field_offset_long(p, offset);
  1206   oop res = oopDesc::atomic_compare_exchange_oop(x, addr, e, true);
  1207   jboolean success  = (res == e);
  1208   if (success)
  1209     update_barrier_set((void*)addr, x);
  1210   return success;
  1211 UNSAFE_END
  1213 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x))
  1214   UnsafeWrapper("Unsafe_CompareAndSwapInt");
  1215   oop p = JNIHandles::resolve(obj);
  1216   jint* addr = (jint *) index_oop_from_field_offset_long(p, offset);
  1217   return (jint)(Atomic::cmpxchg(x, addr, e)) == e;
  1218 UNSAFE_END
  1220 UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x))
  1221   UnsafeWrapper("Unsafe_CompareAndSwapLong");
  1222   Handle p (THREAD, JNIHandles::resolve(obj));
  1223   jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
  1224 #ifdef SUPPORTS_NATIVE_CX8
  1225   return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
  1226 #else
  1227   if (VM_Version::supports_cx8())
  1228     return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
  1229   else {
  1230     jboolean success = false;
  1231     MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag);
  1232     jlong val = Atomic::load(addr);
  1233     if (val == e) { Atomic::store(x, addr); success = true; }
  1234     return success;
  1236 #endif
  1237 UNSAFE_END
  1239 UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time))
  1240   UnsafeWrapper("Unsafe_Park");
  1241   EventThreadPark event;
  1242 #ifndef USDT2
  1243   HS_DTRACE_PROBE3(hotspot, thread__park__begin, thread->parker(), (int) isAbsolute, time);
  1244 #else /* USDT2 */
  1245    HOTSPOT_THREAD_PARK_BEGIN(
  1246                              (uintptr_t) thread->parker(), (int) isAbsolute, time);
  1247 #endif /* USDT2 */
  1248   JavaThreadParkedState jtps(thread, time != 0);
  1249   thread->parker()->park(isAbsolute != 0, time);
  1250 #ifndef USDT2
  1251   HS_DTRACE_PROBE1(hotspot, thread__park__end, thread->parker());
  1252 #else /* USDT2 */
  1253   HOTSPOT_THREAD_PARK_END(
  1254                           (uintptr_t) thread->parker());
  1255 #endif /* USDT2 */
  1256   if (event.should_commit()) {
  1257     oop obj = thread->current_park_blocker();
  1258     event.set_klass((obj != NULL) ? obj->klass() : NULL);
  1259     event.set_timeout(time);
  1260     event.set_address((obj != NULL) ? (TYPE_ADDRESS) cast_from_oop<uintptr_t>(obj) : 0);
  1261     event.commit();
  1263 UNSAFE_END
  1265 UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread))
  1266   UnsafeWrapper("Unsafe_Unpark");
  1267   Parker* p = NULL;
  1268   if (jthread != NULL) {
  1269     oop java_thread = JNIHandles::resolve_non_null(jthread);
  1270     if (java_thread != NULL) {
  1271       jlong lp = java_lang_Thread::park_event(java_thread);
  1272       if (lp != 0) {
  1273         // This cast is OK even though the jlong might have been read
  1274         // non-atomically on 32bit systems, since there, one word will
  1275         // always be zero anyway and the value set is always the same
  1276         p = (Parker*)addr_from_java(lp);
  1277       } else {
  1278         // Grab lock if apparently null or using older version of library
  1279         MutexLocker mu(Threads_lock);
  1280         java_thread = JNIHandles::resolve_non_null(jthread);
  1281         if (java_thread != NULL) {
  1282           JavaThread* thr = java_lang_Thread::thread(java_thread);
  1283           if (thr != NULL) {
  1284             p = thr->parker();
  1285             if (p != NULL) { // Bind to Java thread for next time.
  1286               java_lang_Thread::set_park_event(java_thread, addr_to_java(p));
  1293   if (p != NULL) {
  1294 #ifndef USDT2
  1295     HS_DTRACE_PROBE1(hotspot, thread__unpark, p);
  1296 #else /* USDT2 */
  1297     HOTSPOT_THREAD_UNPARK(
  1298                           (uintptr_t) p);
  1299 #endif /* USDT2 */
  1300     p->unpark();
  1302 UNSAFE_END
  1304 UNSAFE_ENTRY(jint, Unsafe_Loadavg(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem))
  1305   UnsafeWrapper("Unsafe_Loadavg");
  1306   const int max_nelem = 3;
  1307   double la[max_nelem];
  1308   jint ret;
  1310   typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
  1311   assert(a->is_typeArray(), "must be type array");
  1313   if (nelem < 0 || nelem > max_nelem || a->length() < nelem) {
  1314     ThreadToNativeFromVM ttnfv(thread);
  1315     throw_new(env, "ArrayIndexOutOfBoundsException");
  1316     return -1;
  1319   ret = os::loadavg(la, nelem);
  1320   if (ret == -1) return -1;
  1322   // if successful, ret is the number of samples actually retrieved.
  1323   assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
  1324   switch(ret) {
  1325     case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
  1326     case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
  1327     case 1: a->double_at_put(0, (jdouble)la[0]); break;
  1329   return ret;
  1330 UNSAFE_END
  1332 UNSAFE_ENTRY(void, Unsafe_PrefetchRead(JNIEnv* env, jclass ignored, jobject obj, jlong offset))
  1333   UnsafeWrapper("Unsafe_PrefetchRead");
  1334   oop p = JNIHandles::resolve(obj);
  1335   void* addr = index_oop_from_field_offset_long(p, 0);
  1336   Prefetch::read(addr, (intx)offset);
  1337 UNSAFE_END
  1339 UNSAFE_ENTRY(void, Unsafe_PrefetchWrite(JNIEnv* env, jclass ignored, jobject obj, jlong offset))
  1340   UnsafeWrapper("Unsafe_PrefetchWrite");
  1341   oop p = JNIHandles::resolve(obj);
  1342   void* addr = index_oop_from_field_offset_long(p, 0);
  1343   Prefetch::write(addr, (intx)offset);
  1344 UNSAFE_END
  1347 /// JVM_RegisterUnsafeMethods
  1349 #define ADR "J"
  1351 #define LANG "Ljava/lang/"
  1353 #define OBJ LANG "Object;"
  1354 #define CLS LANG "Class;"
  1355 #define CTR LANG "reflect/Constructor;"
  1356 #define FLD LANG "reflect/Field;"
  1357 #define MTH LANG "reflect/Method;"
  1358 #define THR LANG "Throwable;"
  1360 #define DC0_Args LANG "String;[BII"
  1361 #define DC_Args  DC0_Args LANG "ClassLoader;" "Ljava/security/ProtectionDomain;"
  1363 #define CC (char*)  /*cast a literal from (const char*)*/
  1364 #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
  1366 // define deprecated accessors for compabitility with 1.4.0
  1367 #define DECLARE_GETSETOOP_140(Boolean, Z) \
  1368     {CC "get" #Boolean,      CC "(" OBJ "I)" #Z,      FN_PTR(Unsafe_Get##Boolean##140)}, \
  1369     {CC "put" #Boolean,      CC "(" OBJ "I" #Z ")V",   FN_PTR(Unsafe_Set##Boolean##140)}
  1371 // Note:  In 1.4.1, getObject and kin take both int and long offsets.
  1372 #define DECLARE_GETSETOOP_141(Boolean, Z) \
  1373     {CC "get" #Boolean,      CC "(" OBJ "J)" #Z,      FN_PTR(Unsafe_Get##Boolean)}, \
  1374     {CC "put" #Boolean,      CC "(" OBJ "J" #Z ")V",   FN_PTR(Unsafe_Set##Boolean)}
  1376 // Note:  In 1.5.0, there are volatile versions too
  1377 #define DECLARE_GETSETOOP(Boolean, Z) \
  1378     {CC "get" #Boolean,      CC "(" OBJ "J)" #Z,      FN_PTR(Unsafe_Get##Boolean)}, \
  1379     {CC "put" #Boolean,      CC "(" OBJ "J" #Z ")V",   FN_PTR(Unsafe_Set##Boolean)}, \
  1380     {CC "get" #Boolean "Volatile",      CC "(" OBJ "J)" #Z,      FN_PTR(Unsafe_Get##Boolean##Volatile)}, \
  1381     {CC "put" #Boolean "Volatile",      CC "(" OBJ "J" #Z ")V",   FN_PTR(Unsafe_Set##Boolean##Volatile)}
  1384 #define DECLARE_GETSETNATIVE(Byte, B) \
  1385     {CC "get" #Byte,         CC "(" ADR ")" #B,       FN_PTR(Unsafe_GetNative##Byte)}, \
  1386     {CC "put" #Byte,         CC "(" ADR#B ")V",      FN_PTR(Unsafe_SetNative##Byte)}
  1390 // These are the methods for 1.4.0
  1391 static JNINativeMethod methods_140[] = {
  1392     {CC "getObject",        CC "(" OBJ "I)" OBJ "",   FN_PTR(Unsafe_GetObject140)},
  1393     {CC "putObject",        CC "(" OBJ "I" OBJ ")V",  FN_PTR(Unsafe_SetObject140)},
  1395     DECLARE_GETSETOOP_140(Boolean, Z),
  1396     DECLARE_GETSETOOP_140(Byte, B),
  1397     DECLARE_GETSETOOP_140(Short, S),
  1398     DECLARE_GETSETOOP_140(Char, C),
  1399     DECLARE_GETSETOOP_140(Int, I),
  1400     DECLARE_GETSETOOP_140(Long, J),
  1401     DECLARE_GETSETOOP_140(Float, F),
  1402     DECLARE_GETSETOOP_140(Double, D),
  1404     DECLARE_GETSETNATIVE(Byte, B),
  1405     DECLARE_GETSETNATIVE(Short, S),
  1406     DECLARE_GETSETNATIVE(Char, C),
  1407     DECLARE_GETSETNATIVE(Int, I),
  1408     DECLARE_GETSETNATIVE(Long, J),
  1409     DECLARE_GETSETNATIVE(Float, F),
  1410     DECLARE_GETSETNATIVE(Double, D),
  1412     {CC "getAddress",         CC "(" ADR ")" ADR,             FN_PTR(Unsafe_GetNativeAddress)},
  1413     {CC "putAddress",         CC "(" ADR "" ADR ")V",          FN_PTR(Unsafe_SetNativeAddress)},
  1415     {CC "allocateMemory",     CC "(J)" ADR,                 FN_PTR(Unsafe_AllocateMemory)},
  1416     {CC "reallocateMemory",   CC "(" ADR "J)" ADR,            FN_PTR(Unsafe_ReallocateMemory)},
  1417     {CC "freeMemory",         CC "(" ADR ")V",               FN_PTR(Unsafe_FreeMemory)},
  1419     {CC "fieldOffset",        CC "(" FLD ")I",               FN_PTR(Unsafe_FieldOffset)},
  1420     {CC "staticFieldBase",    CC "(" CLS ")" OBJ,             FN_PTR(Unsafe_StaticFieldBaseFromClass)},
  1421     {CC "ensureClassInitialized",CC "(" CLS ")V",            FN_PTR(Unsafe_EnsureClassInitialized)},
  1422     {CC "arrayBaseOffset",    CC "(" CLS ")I",               FN_PTR(Unsafe_ArrayBaseOffset)},
  1423     {CC "arrayIndexScale",    CC "(" CLS ")I",               FN_PTR(Unsafe_ArrayIndexScale)},
  1424     {CC "addressSize",        CC "()I",                    FN_PTR(Unsafe_AddressSize)},
  1425     {CC "pageSize",           CC "()I",                    FN_PTR(Unsafe_PageSize)},
  1427     {CC "defineClass",        CC "(" DC0_Args ")" CLS,        FN_PTR(Unsafe_DefineClass0)},
  1428     {CC "defineClass",        CC "(" DC_Args ")" CLS,         FN_PTR(Unsafe_DefineClass)},
  1429     {CC "allocateInstance",   CC "(" CLS ")" OBJ,             FN_PTR(Unsafe_AllocateInstance)},
  1430     {CC "monitorEnter",       CC "(" OBJ ")V",               FN_PTR(Unsafe_MonitorEnter)},
  1431     {CC "monitorExit",        CC "(" OBJ ")V",               FN_PTR(Unsafe_MonitorExit)},
  1432     {CC "throwException",     CC "(" THR ")V",               FN_PTR(Unsafe_ThrowException)}
  1433 };
  1435 // These are the methods prior to the JSR 166 changes in 1.5.0
  1436 static JNINativeMethod methods_141[] = {
  1437     {CC "getObject",        CC "(" OBJ "J)" OBJ "",   FN_PTR(Unsafe_GetObject)},
  1438     {CC "putObject",        CC "(" OBJ "J" OBJ ")V",  FN_PTR(Unsafe_SetObject)},
  1440     DECLARE_GETSETOOP_141(Boolean, Z),
  1441     DECLARE_GETSETOOP_141(Byte, B),
  1442     DECLARE_GETSETOOP_141(Short, S),
  1443     DECLARE_GETSETOOP_141(Char, C),
  1444     DECLARE_GETSETOOP_141(Int, I),
  1445     DECLARE_GETSETOOP_141(Long, J),
  1446     DECLARE_GETSETOOP_141(Float, F),
  1447     DECLARE_GETSETOOP_141(Double, D),
  1449     DECLARE_GETSETNATIVE(Byte, B),
  1450     DECLARE_GETSETNATIVE(Short, S),
  1451     DECLARE_GETSETNATIVE(Char, C),
  1452     DECLARE_GETSETNATIVE(Int, I),
  1453     DECLARE_GETSETNATIVE(Long, J),
  1454     DECLARE_GETSETNATIVE(Float, F),
  1455     DECLARE_GETSETNATIVE(Double, D),
  1457     {CC "getAddress",         CC "(" ADR ")" ADR,             FN_PTR(Unsafe_GetNativeAddress)},
  1458     {CC "putAddress",         CC "(" ADR "" ADR ")V",          FN_PTR(Unsafe_SetNativeAddress)},
  1460     {CC "allocateMemory",     CC "(J)" ADR,                 FN_PTR(Unsafe_AllocateMemory)},
  1461     {CC "reallocateMemory",   CC "(" ADR "J)" ADR,            FN_PTR(Unsafe_ReallocateMemory)},
  1462     {CC "freeMemory",         CC "(" ADR ")V",               FN_PTR(Unsafe_FreeMemory)},
  1464     {CC "objectFieldOffset",  CC "(" FLD ")J",               FN_PTR(Unsafe_ObjectFieldOffset)},
  1465     {CC "staticFieldOffset",  CC "(" FLD ")J",               FN_PTR(Unsafe_StaticFieldOffset)},
  1466     {CC "staticFieldBase",    CC "(" FLD ")" OBJ,             FN_PTR(Unsafe_StaticFieldBaseFromField)},
  1467     {CC "ensureClassInitialized",CC "(" CLS ")V",            FN_PTR(Unsafe_EnsureClassInitialized)},
  1468     {CC "arrayBaseOffset",    CC "(" CLS ")I",               FN_PTR(Unsafe_ArrayBaseOffset)},
  1469     {CC "arrayIndexScale",    CC "(" CLS ")I",               FN_PTR(Unsafe_ArrayIndexScale)},
  1470     {CC "addressSize",        CC "()I",                    FN_PTR(Unsafe_AddressSize)},
  1471     {CC "pageSize",           CC "()I",                    FN_PTR(Unsafe_PageSize)},
  1473     {CC "defineClass",        CC "(" DC0_Args ")" CLS,        FN_PTR(Unsafe_DefineClass0)},
  1474     {CC "defineClass",        CC "(" DC_Args ")" CLS,         FN_PTR(Unsafe_DefineClass)},
  1475     {CC "allocateInstance",   CC "(" CLS ")" OBJ,             FN_PTR(Unsafe_AllocateInstance)},
  1476     {CC "monitorEnter",       CC "(" OBJ ")V",               FN_PTR(Unsafe_MonitorEnter)},
  1477     {CC "monitorExit",        CC "(" OBJ ")V",               FN_PTR(Unsafe_MonitorExit)},
  1478     {CC "throwException",     CC "(" THR ")V",               FN_PTR(Unsafe_ThrowException)}
  1480 };
  1482 // These are the methods prior to the JSR 166 changes in 1.6.0
  1483 static JNINativeMethod methods_15[] = {
  1484     {CC "getObject",        CC "(" OBJ "J)" OBJ "",   FN_PTR(Unsafe_GetObject)},
  1485     {CC "putObject",        CC "(" OBJ "J" OBJ ")V",  FN_PTR(Unsafe_SetObject)},
  1486     {CC "getObjectVolatile",CC "(" OBJ "J)" OBJ "",   FN_PTR(Unsafe_GetObjectVolatile)},
  1487     {CC "putObjectVolatile",CC "(" OBJ "J" OBJ ")V",  FN_PTR(Unsafe_SetObjectVolatile)},
  1490     DECLARE_GETSETOOP(Boolean, Z),
  1491     DECLARE_GETSETOOP(Byte, B),
  1492     DECLARE_GETSETOOP(Short, S),
  1493     DECLARE_GETSETOOP(Char, C),
  1494     DECLARE_GETSETOOP(Int, I),
  1495     DECLARE_GETSETOOP(Long, J),
  1496     DECLARE_GETSETOOP(Float, F),
  1497     DECLARE_GETSETOOP(Double, D),
  1499     DECLARE_GETSETNATIVE(Byte, B),
  1500     DECLARE_GETSETNATIVE(Short, S),
  1501     DECLARE_GETSETNATIVE(Char, C),
  1502     DECLARE_GETSETNATIVE(Int, I),
  1503     DECLARE_GETSETNATIVE(Long, J),
  1504     DECLARE_GETSETNATIVE(Float, F),
  1505     DECLARE_GETSETNATIVE(Double, D),
  1507     {CC "getAddress",         CC "(" ADR ")" ADR,             FN_PTR(Unsafe_GetNativeAddress)},
  1508     {CC "putAddress",         CC "(" ADR "" ADR ")V",          FN_PTR(Unsafe_SetNativeAddress)},
  1510     {CC "allocateMemory",     CC "(J)" ADR,                 FN_PTR(Unsafe_AllocateMemory)},
  1511     {CC "reallocateMemory",   CC "(" ADR "J)" ADR,            FN_PTR(Unsafe_ReallocateMemory)},
  1512     {CC "freeMemory",         CC "(" ADR ")V",               FN_PTR(Unsafe_FreeMemory)},
  1514     {CC "objectFieldOffset",  CC "(" FLD ")J",               FN_PTR(Unsafe_ObjectFieldOffset)},
  1515     {CC "staticFieldOffset",  CC "(" FLD ")J",               FN_PTR(Unsafe_StaticFieldOffset)},
  1516     {CC "staticFieldBase",    CC "(" FLD ")" OBJ,             FN_PTR(Unsafe_StaticFieldBaseFromField)},
  1517     {CC "ensureClassInitialized",CC "(" CLS ")V",            FN_PTR(Unsafe_EnsureClassInitialized)},
  1518     {CC "arrayBaseOffset",    CC "(" CLS ")I",               FN_PTR(Unsafe_ArrayBaseOffset)},
  1519     {CC "arrayIndexScale",    CC "(" CLS ")I",               FN_PTR(Unsafe_ArrayIndexScale)},
  1520     {CC "addressSize",        CC "()I",                    FN_PTR(Unsafe_AddressSize)},
  1521     {CC "pageSize",           CC "()I",                    FN_PTR(Unsafe_PageSize)},
  1523     {CC "defineClass",        CC "(" DC0_Args ")" CLS,        FN_PTR(Unsafe_DefineClass0)},
  1524     {CC "defineClass",        CC "(" DC_Args ")" CLS,         FN_PTR(Unsafe_DefineClass)},
  1525     {CC "allocateInstance",   CC "(" CLS ")" OBJ,             FN_PTR(Unsafe_AllocateInstance)},
  1526     {CC "monitorEnter",       CC "(" OBJ ")V",               FN_PTR(Unsafe_MonitorEnter)},
  1527     {CC "monitorExit",        CC "(" OBJ ")V",               FN_PTR(Unsafe_MonitorExit)},
  1528     {CC "throwException",     CC "(" THR ")V",               FN_PTR(Unsafe_ThrowException)},
  1529     {CC "compareAndSwapObject", CC "(" OBJ "J" OBJ "" OBJ ")Z",  FN_PTR(Unsafe_CompareAndSwapObject)},
  1530     {CC "compareAndSwapInt",  CC "(" OBJ "J""I""I"")Z",      FN_PTR(Unsafe_CompareAndSwapInt)},
  1531     {CC "compareAndSwapLong", CC "(" OBJ "J""J""J"")Z",      FN_PTR(Unsafe_CompareAndSwapLong)},
  1532     {CC "park",               CC "(ZJ)V",                  FN_PTR(Unsafe_Park)},
  1533     {CC "unpark",             CC "(" OBJ ")V",               FN_PTR(Unsafe_Unpark)}
  1535 };
  1537 // These are the methods for 1.6.0 and 1.7.0
  1538 static JNINativeMethod methods_16[] = {
  1539     {CC "getObject",        CC "(" OBJ "J)" OBJ "",   FN_PTR(Unsafe_GetObject)},
  1540     {CC "putObject",        CC "(" OBJ "J" OBJ ")V",  FN_PTR(Unsafe_SetObject)},
  1541     {CC "getObjectVolatile",CC "(" OBJ "J)" OBJ "",   FN_PTR(Unsafe_GetObjectVolatile)},
  1542     {CC "putObjectVolatile",CC "(" OBJ "J" OBJ ")V",  FN_PTR(Unsafe_SetObjectVolatile)},
  1544     DECLARE_GETSETOOP(Boolean, Z),
  1545     DECLARE_GETSETOOP(Byte, B),
  1546     DECLARE_GETSETOOP(Short, S),
  1547     DECLARE_GETSETOOP(Char, C),
  1548     DECLARE_GETSETOOP(Int, I),
  1549     DECLARE_GETSETOOP(Long, J),
  1550     DECLARE_GETSETOOP(Float, F),
  1551     DECLARE_GETSETOOP(Double, D),
  1553     DECLARE_GETSETNATIVE(Byte, B),
  1554     DECLARE_GETSETNATIVE(Short, S),
  1555     DECLARE_GETSETNATIVE(Char, C),
  1556     DECLARE_GETSETNATIVE(Int, I),
  1557     DECLARE_GETSETNATIVE(Long, J),
  1558     DECLARE_GETSETNATIVE(Float, F),
  1559     DECLARE_GETSETNATIVE(Double, D),
  1561     {CC "getAddress",         CC "(" ADR ")" ADR,             FN_PTR(Unsafe_GetNativeAddress)},
  1562     {CC "putAddress",         CC "(" ADR "" ADR ")V",          FN_PTR(Unsafe_SetNativeAddress)},
  1564     {CC "allocateMemory",     CC "(J)" ADR,                 FN_PTR(Unsafe_AllocateMemory)},
  1565     {CC "reallocateMemory",   CC "(" ADR "J)" ADR,            FN_PTR(Unsafe_ReallocateMemory)},
  1566     {CC "freeMemory",         CC "(" ADR ")V",               FN_PTR(Unsafe_FreeMemory)},
  1568     {CC "objectFieldOffset",  CC "(" FLD ")J",               FN_PTR(Unsafe_ObjectFieldOffset)},
  1569     {CC "staticFieldOffset",  CC "(" FLD ")J",               FN_PTR(Unsafe_StaticFieldOffset)},
  1570     {CC "staticFieldBase",    CC "(" FLD ")" OBJ,             FN_PTR(Unsafe_StaticFieldBaseFromField)},
  1571     {CC "ensureClassInitialized",CC "(" CLS ")V",            FN_PTR(Unsafe_EnsureClassInitialized)},
  1572     {CC "arrayBaseOffset",    CC "(" CLS ")I",               FN_PTR(Unsafe_ArrayBaseOffset)},
  1573     {CC "arrayIndexScale",    CC "(" CLS ")I",               FN_PTR(Unsafe_ArrayIndexScale)},
  1574     {CC "addressSize",        CC "()I",                    FN_PTR(Unsafe_AddressSize)},
  1575     {CC "pageSize",           CC "()I",                    FN_PTR(Unsafe_PageSize)},
  1577     {CC "defineClass",        CC "(" DC0_Args ")" CLS,        FN_PTR(Unsafe_DefineClass0)},
  1578     {CC "defineClass",        CC "(" DC_Args ")" CLS,         FN_PTR(Unsafe_DefineClass)},
  1579     {CC "allocateInstance",   CC "(" CLS ")" OBJ,             FN_PTR(Unsafe_AllocateInstance)},
  1580     {CC "monitorEnter",       CC "(" OBJ ")V",               FN_PTR(Unsafe_MonitorEnter)},
  1581     {CC "monitorExit",        CC "(" OBJ ")V",               FN_PTR(Unsafe_MonitorExit)},
  1582     {CC "tryMonitorEnter",    CC "(" OBJ ")Z",               FN_PTR(Unsafe_TryMonitorEnter)},
  1583     {CC "throwException",     CC "(" THR ")V",               FN_PTR(Unsafe_ThrowException)},
  1584     {CC "compareAndSwapObject", CC "(" OBJ "J" OBJ "" OBJ ")Z",  FN_PTR(Unsafe_CompareAndSwapObject)},
  1585     {CC "compareAndSwapInt",  CC "(" OBJ "J""I""I"")Z",      FN_PTR(Unsafe_CompareAndSwapInt)},
  1586     {CC "compareAndSwapLong", CC "(" OBJ "J""J""J"")Z",      FN_PTR(Unsafe_CompareAndSwapLong)},
  1587     {CC "putOrderedObject",   CC "(" OBJ "J" OBJ ")V",         FN_PTR(Unsafe_SetOrderedObject)},
  1588     {CC "putOrderedInt",      CC "(" OBJ "JI)V",             FN_PTR(Unsafe_SetOrderedInt)},
  1589     {CC "putOrderedLong",     CC "(" OBJ "JJ)V",             FN_PTR(Unsafe_SetOrderedLong)},
  1590     {CC "park",               CC "(ZJ)V",                  FN_PTR(Unsafe_Park)},
  1591     {CC "unpark",             CC "(" OBJ ")V",               FN_PTR(Unsafe_Unpark)}
  1592 };
  1594 // These are the methods for 1.8.0
  1595 static JNINativeMethod methods_18[] = {
  1596     {CC "getObject",        CC "(" OBJ "J)" OBJ "",   FN_PTR(Unsafe_GetObject)},
  1597     {CC "putObject",        CC "(" OBJ "J" OBJ ")V",  FN_PTR(Unsafe_SetObject)},
  1598     {CC "getObjectVolatile",CC "(" OBJ "J)" OBJ "",   FN_PTR(Unsafe_GetObjectVolatile)},
  1599     {CC "putObjectVolatile",CC "(" OBJ "J" OBJ ")V",  FN_PTR(Unsafe_SetObjectVolatile)},
  1601     DECLARE_GETSETOOP(Boolean, Z),
  1602     DECLARE_GETSETOOP(Byte, B),
  1603     DECLARE_GETSETOOP(Short, S),
  1604     DECLARE_GETSETOOP(Char, C),
  1605     DECLARE_GETSETOOP(Int, I),
  1606     DECLARE_GETSETOOP(Long, J),
  1607     DECLARE_GETSETOOP(Float, F),
  1608     DECLARE_GETSETOOP(Double, D),
  1610     DECLARE_GETSETNATIVE(Byte, B),
  1611     DECLARE_GETSETNATIVE(Short, S),
  1612     DECLARE_GETSETNATIVE(Char, C),
  1613     DECLARE_GETSETNATIVE(Int, I),
  1614     DECLARE_GETSETNATIVE(Long, J),
  1615     DECLARE_GETSETNATIVE(Float, F),
  1616     DECLARE_GETSETNATIVE(Double, D),
  1618     {CC "getAddress",         CC "(" ADR ")" ADR,             FN_PTR(Unsafe_GetNativeAddress)},
  1619     {CC "putAddress",         CC "(" ADR "" ADR ")V",          FN_PTR(Unsafe_SetNativeAddress)},
  1621     {CC "allocateMemory",     CC "(J)" ADR,                 FN_PTR(Unsafe_AllocateMemory)},
  1622     {CC "reallocateMemory",   CC "(" ADR "J)" ADR,            FN_PTR(Unsafe_ReallocateMemory)},
  1623     {CC "freeMemory",         CC "(" ADR ")V",               FN_PTR(Unsafe_FreeMemory)},
  1625     {CC "objectFieldOffset",  CC "(" FLD ")J",               FN_PTR(Unsafe_ObjectFieldOffset)},
  1626     {CC "staticFieldOffset",  CC "(" FLD ")J",               FN_PTR(Unsafe_StaticFieldOffset)},
  1627     {CC "staticFieldBase",    CC "(" FLD ")" OBJ,             FN_PTR(Unsafe_StaticFieldBaseFromField)},
  1628     {CC "ensureClassInitialized",CC "(" CLS ")V",            FN_PTR(Unsafe_EnsureClassInitialized)},
  1629     {CC "arrayBaseOffset",    CC "(" CLS ")I",               FN_PTR(Unsafe_ArrayBaseOffset)},
  1630     {CC "arrayIndexScale",    CC "(" CLS ")I",               FN_PTR(Unsafe_ArrayIndexScale)},
  1631     {CC "addressSize",        CC "()I",                    FN_PTR(Unsafe_AddressSize)},
  1632     {CC "pageSize",           CC "()I",                    FN_PTR(Unsafe_PageSize)},
  1634     {CC "defineClass",        CC "(" DC_Args ")" CLS,         FN_PTR(Unsafe_DefineClass)},
  1635     {CC "allocateInstance",   CC "(" CLS ")" OBJ,             FN_PTR(Unsafe_AllocateInstance)},
  1636     {CC "monitorEnter",       CC "(" OBJ ")V",               FN_PTR(Unsafe_MonitorEnter)},
  1637     {CC "monitorExit",        CC "(" OBJ ")V",               FN_PTR(Unsafe_MonitorExit)},
  1638     {CC "tryMonitorEnter",    CC "(" OBJ ")Z",               FN_PTR(Unsafe_TryMonitorEnter)},
  1639     {CC "throwException",     CC "(" THR ")V",               FN_PTR(Unsafe_ThrowException)},
  1640     {CC "compareAndSwapObject", CC "(" OBJ "J" OBJ "" OBJ ")Z",  FN_PTR(Unsafe_CompareAndSwapObject)},
  1641     {CC "compareAndSwapInt",  CC "(" OBJ "J""I""I"")Z",      FN_PTR(Unsafe_CompareAndSwapInt)},
  1642     {CC "compareAndSwapLong", CC "(" OBJ "J""J""J"")Z",      FN_PTR(Unsafe_CompareAndSwapLong)},
  1643     {CC "putOrderedObject",   CC "(" OBJ "J" OBJ ")V",         FN_PTR(Unsafe_SetOrderedObject)},
  1644     {CC "putOrderedInt",      CC "(" OBJ "JI)V",             FN_PTR(Unsafe_SetOrderedInt)},
  1645     {CC "putOrderedLong",     CC "(" OBJ "JJ)V",             FN_PTR(Unsafe_SetOrderedLong)},
  1646     {CC "park",               CC "(ZJ)V",                  FN_PTR(Unsafe_Park)},
  1647     {CC "unpark",             CC "(" OBJ ")V",               FN_PTR(Unsafe_Unpark)}
  1648 };
  1650 JNINativeMethod loadavg_method[] = {
  1651     {CC "getLoadAverage",     CC "([DI)I",                 FN_PTR(Unsafe_Loadavg)}
  1652 };
  1654 JNINativeMethod prefetch_methods[] = {
  1655     {CC "prefetchRead",       CC "(" OBJ "J)V",              FN_PTR(Unsafe_PrefetchRead)},
  1656     {CC "prefetchWrite",      CC "(" OBJ "J)V",              FN_PTR(Unsafe_PrefetchWrite)},
  1657     {CC "prefetchReadStatic", CC "(" OBJ "J)V",              FN_PTR(Unsafe_PrefetchRead)},
  1658     {CC "prefetchWriteStatic",CC "(" OBJ "J)V",              FN_PTR(Unsafe_PrefetchWrite)}
  1659 };
  1661 JNINativeMethod memcopy_methods_17[] = {
  1662     {CC "copyMemory",         CC "(" OBJ "J" OBJ "JJ)V",       FN_PTR(Unsafe_CopyMemory2)},
  1663     {CC "setMemory",          CC "(" OBJ "JJB)V",            FN_PTR(Unsafe_SetMemory2)}
  1664 };
  1666 JNINativeMethod memcopy_methods_15[] = {
  1667     {CC "setMemory",          CC "(" ADR "JB)V",             FN_PTR(Unsafe_SetMemory)},
  1668     {CC "copyMemory",         CC "(" ADR ADR "J)V",          FN_PTR(Unsafe_CopyMemory)}
  1669 };
  1671 JNINativeMethod anonk_methods[] = {
  1672     {CC "defineAnonymousClass", CC "(" DAC_Args ")" CLS,      FN_PTR(Unsafe_DefineAnonymousClass)},
  1673 };
  1675 JNINativeMethod lform_methods[] = {
  1676     {CC "shouldBeInitialized",CC "(" CLS ")Z",               FN_PTR(Unsafe_ShouldBeInitialized)},
  1677 };
  1679 JNINativeMethod fence_methods[] = {
  1680     {CC "loadFence",          CC "()V",                    FN_PTR(Unsafe_LoadFence)},
  1681     {CC "storeFence",         CC "()V",                    FN_PTR(Unsafe_StoreFence)},
  1682     {CC "fullFence",          CC "()V",                    FN_PTR(Unsafe_FullFence)},
  1683 };
  1685 #undef CC
  1686 #undef FN_PTR
  1688 #undef ADR
  1689 #undef LANG
  1690 #undef OBJ
  1691 #undef CLS
  1692 #undef CTR
  1693 #undef FLD
  1694 #undef MTH
  1695 #undef THR
  1696 #undef DC0_Args
  1697 #undef DC_Args
  1699 #undef DECLARE_GETSETOOP
  1700 #undef DECLARE_GETSETNATIVE
  1703 /**
  1704  * Helper method to register native methods.
  1705  */
  1706 static bool register_natives(const char* message, JNIEnv* env, jclass clazz, const JNINativeMethod* methods, jint nMethods) {
  1707   int status = env->RegisterNatives(clazz, methods, nMethods);
  1708   if (status < 0 || env->ExceptionOccurred()) {
  1709     if (PrintMiscellaneous && (Verbose || WizardMode)) {
  1710       tty->print_cr("Unsafe:  failed registering %s", message);
  1712     env->ExceptionClear();
  1713     return false;
  1714   } else {
  1715     if (PrintMiscellaneous && (Verbose || WizardMode)) {
  1716       tty->print_cr("Unsafe:  successfully registered %s", message);
  1718     return true;
  1723 // This one function is exported, used by NativeLookup.
  1724 // The Unsafe_xxx functions above are called only from the interpreter.
  1725 // The optimizer looks at names and signatures to recognize
  1726 // individual functions.
  1728 JVM_ENTRY(void, JVM_RegisterUnsafeMethods(JNIEnv *env, jclass unsafecls))
  1729   UnsafeWrapper("JVM_RegisterUnsafeMethods");
  1731     ThreadToNativeFromVM ttnfv(thread);
  1733     // Unsafe methods
  1735       bool success = false;
  1736       // We need to register the 1.6 methods first because the 1.8 methods would register fine on 1.7 and 1.6
  1737       if (!success) {
  1738         success = register_natives("1.6 methods",   env, unsafecls, methods_16,  sizeof(methods_16)/sizeof(JNINativeMethod));
  1740       if (!success) {
  1741         success = register_natives("1.8 methods",   env, unsafecls, methods_18,  sizeof(methods_18)/sizeof(JNINativeMethod));
  1743       if (!success) {
  1744         success = register_natives("1.5 methods",   env, unsafecls, methods_15,  sizeof(methods_15)/sizeof(JNINativeMethod));
  1746       if (!success) {
  1747         success = register_natives("1.4.1 methods", env, unsafecls, methods_141, sizeof(methods_141)/sizeof(JNINativeMethod));
  1749       if (!success) {
  1750         success = register_natives("1.4.0 methods", env, unsafecls, methods_140, sizeof(methods_140)/sizeof(JNINativeMethod));
  1752       guarantee(success, "register unsafe natives");
  1755     // Unsafe.getLoadAverage
  1756     register_natives("1.6 loadavg method", env, unsafecls, loadavg_method, sizeof(loadavg_method)/sizeof(JNINativeMethod));
  1758     // Prefetch methods
  1759     register_natives("1.6 prefetch methods", env, unsafecls, prefetch_methods, sizeof(prefetch_methods)/sizeof(JNINativeMethod));
  1761     // Memory copy methods
  1763       bool success = false;
  1764       if (!success) {
  1765         success = register_natives("1.7 memory copy methods", env, unsafecls, memcopy_methods_17, sizeof(memcopy_methods_17)/sizeof(JNINativeMethod));
  1767       if (!success) {
  1768         success = register_natives("1.5 memory copy methods", env, unsafecls, memcopy_methods_15, sizeof(memcopy_methods_15)/sizeof(JNINativeMethod));
  1772     // Unsafe.defineAnonymousClass
  1773     if (EnableInvokeDynamic) {
  1774       register_natives("1.7 define anonymous class method", env, unsafecls, anonk_methods, sizeof(anonk_methods)/sizeof(JNINativeMethod));
  1777     // Unsafe.shouldBeInitialized
  1778     if (EnableInvokeDynamic) {
  1779       register_natives("1.7 LambdaForm support", env, unsafecls, lform_methods, sizeof(lform_methods)/sizeof(JNINativeMethod));
  1782     // Fence methods
  1783     register_natives("1.8 fence methods", env, unsafecls, fence_methods, sizeof(fence_methods)/sizeof(JNINativeMethod));
  1785 JVM_END

mercurial