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JVM 中 unsafe.cpp 源码

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发布于: 2020 年 09 月 03 日
JVM中unsafe.cpp源码

Unsafe.java中有部分native方法,如果感兴趣的同学可以查看JVM中对应的C++代码(我看不懂😂),感兴趣的同学可以看看,并进行留言,可以交流学习。

/*
* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "classfile/vmSymbols.hpp"
#include "utilities/macros.hpp"
#if INCLUDE_ALL_GCS
#include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
#endif // INCLUDE_ALL_GCS
#include "memory/allocation.inline.hpp"
#include "prims/jni.h"
#include "prims/jvm.h"
#include "runtime/globals.hpp"
#include "runtime/interfaceSupport.hpp"
#include "runtime/reflection.hpp"
#include "runtime/synchronizer.hpp"
#include "services/threadService.hpp"
#include "trace/tracing.hpp"
#include "utilities/copy.hpp"
#include "utilities/dtrace.hpp"
/*
* Implementation of class sun.misc.Unsafe
*/
#ifndef USDT2
HS_DTRACE_PROBE_DECL3(hotspot, thread__park__begin, uintptr_t, int, long long);
HS_DTRACE_PROBE_DECL1(hotspot, thread__park__end, uintptr_t);
HS_DTRACE_PROBE_DECL1(hotspot, thread__unpark, uintptr_t);
#endif /* !USDT2 */
#define MAX_OBJECT_SIZE \
( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \
+ ((julong)max_jint * sizeof(double)) )
#define UNSAFE_ENTRY(result_type, header) \
JVM_ENTRY(result_type, header)
// Can't use UNSAFE_LEAF because it has the signature of a straight
// call into the runtime (just like JVM_LEAF, funny that) but it's
// called like a Java Native and thus the wrapper built for it passes
// arguments like a JNI call. It expects those arguments to be popped
// from the stack on Intel like all good JNI args are, and adjusts the
// stack according. Since the JVM_LEAF call expects no extra
// arguments the stack isn't popped in the C code, is pushed by the
// wrapper and we get sick.
//#define UNSAFE_LEAF(result_type, header) \
// JVM_LEAF(result_type, header)
#define UNSAFE_END JVM_END
#define UnsafeWrapper(arg) /*nothing, for the present*/
inline void* addr_from_java(jlong addr) {
// This assert fails in a variety of ways on 32-bit systems.
// It is impossible to predict whether native code that converts
// pointers to longs will sign-extend or zero-extend the addresses.
//assert(addr == (uintptr_t)addr, "must not be odd high bits");
return (void*)(uintptr_t)addr;
}
inline jlong addr_to_java(void* p) {
assert(p == (void*)(uintptr_t)p, "must not be odd high bits");
return (uintptr_t)p;
}
// Note: The VM's obj_field and related accessors use byte-scaled
// ("unscaled") offsets, just as the unsafe methods do.
// However, the method Unsafe.fieldOffset explicitly declines to
// guarantee this. The field offset values manipulated by the Java user
// through the Unsafe API are opaque cookies that just happen to be byte
// offsets. We represent this state of affairs by passing the cookies
// through conversion functions when going between the VM and the Unsafe API.
// The conversion functions just happen to be no-ops at present.
inline jlong field_offset_to_byte_offset(jlong field_offset) {
return field_offset;
}
inline jlong field_offset_from_byte_offset(jlong byte_offset) {
return byte_offset;
}
inline jint invocation_key_from_method_slot(jint slot) {
return slot;
}
inline jint invocation_key_to_method_slot(jint key) {
return key;
}
inline void* index_oop_from_field_offset_long(oop p, jlong field_offset) {
jlong byte_offset = field_offset_to_byte_offset(field_offset);
#ifdef ASSERT
if (p != NULL) {
assert(byte_offset >= 0 && byte_offset <= (jlong)MAX_OBJECT_SIZE, "sane offset");
if (byte_offset == (jint)byte_offset) {
void* ptr_plus_disp = (address)p + byte_offset;
assert((void*)p->obj_field_addr<oop>((jint)byte_offset) == ptr_plus_disp,
"raw [ptr+disp] must be consistent with oop::field_base");
}
jlong p_size = HeapWordSize * (jlong)(p->size());
assert(byte_offset < p_size, err_msg("Unsafe access: offset " INT64_FORMAT " > object's size " INT64_FORMAT, byte_offset, p_size));
}
#endif
if (sizeof(char*) == sizeof(jint)) // (this constant folds!)
return (address)p + (jint) byte_offset;
else
return (address)p + byte_offset;
}
// Externally callable versions:
// (Use these in compiler intrinsics which emulate unsafe primitives.)
jlong Unsafe_field_offset_to_byte_offset(jlong field_offset) {
return field_offset;
}
jlong Unsafe_field_offset_from_byte_offset(jlong byte_offset) {
return byte_offset;
}
jint Unsafe_invocation_key_from_method_slot(jint slot) {
return invocation_key_from_method_slot(slot);
}
jint Unsafe_invocation_key_to_method_slot(jint key) {
return invocation_key_to_method_slot(key);
}
///// Data in the Java heap.
#define GET_FIELD(obj, offset, type_name, v) \
oop p = JNIHandles::resolve(obj); \
type_name v = *(type_name*)index_oop_from_field_offset_long(p, offset)
#define SET_FIELD(obj, offset, type_name, x) \
oop p = JNIHandles::resolve(obj); \
*(type_name*)index_oop_from_field_offset_long(p, offset) = x
#define GET_FIELD_VOLATILE(obj, offset, type_name, v) \
oop p = JNIHandles::resolve(obj); \
volatile type_name v = OrderAccess::load_acquire((volatile type_name*)index_oop_from_field_offset_long(p, offset));
#define SET_FIELD_VOLATILE(obj, offset, type_name, x) \
oop p = JNIHandles::resolve(obj); \
OrderAccess::release_store_fence((volatile type_name*)index_oop_from_field_offset_long(p, offset), x);
// Macros for oops that check UseCompressedOops
#define GET_OOP_FIELD(obj, offset, v) \
oop p = JNIHandles::resolve(obj); \
oop v; \
if (UseCompressedOops) { \
narrowOop n = *(narrowOop*)index_oop_from_field_offset_long(p, offset); \
v = oopDesc::decode_heap_oop(n); \
} else { \
v = *(oop*)index_oop_from_field_offset_long(p, offset); \
}
// Get/SetObject must be special-cased, since it works with handles.
// The xxx140 variants for backward compatibility do not allow a full-width offset.
UNSAFE_ENTRY(jobject, Unsafe_GetObject140(JNIEnv *env, jobject unsafe, jobject obj, jint offset))
UnsafeWrapper("Unsafe_GetObject");
if (obj == NULL) THROW_0(vmSymbols::java_lang_NullPointerException());
GET_OOP_FIELD(obj, offset, v)
jobject ret = JNIHandles::make_local(env, v);
#if INCLUDE_ALL_GCS
// We could be accessing the referent field in a reference
// object. If G1 is enabled then we need to register a non-null
// referent with the SATB barrier.
if (UseG1GC) {
bool needs_barrier = false;
if (ret != NULL) {
if (offset == java_lang_ref_Reference::referent_offset) {
oop o = JNIHandles::resolve_non_null(obj);
Klass* k = o->klass();
if (InstanceKlass::cast(k)->reference_type() != REF_NONE) {
assert(InstanceKlass::cast(k)->is_subclass_of(SystemDictionary::Reference_klass()), "sanity");
needs_barrier = true;
}
}
}
if (needs_barrier) {
oop referent = JNIHandles::resolve(ret);
G1SATBCardTableModRefBS::enqueue(referent);
}
}
#endif // INCLUDE_ALL_GCS
return ret;
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_SetObject140(JNIEnv *env, jobject unsafe, jobject obj, jint offset, jobject x_h))
UnsafeWrapper("Unsafe_SetObject");
if (obj == NULL) THROW(vmSymbols::java_lang_NullPointerException());
oop x = JNIHandles::resolve(x_h);
//SET_FIELD(obj, offset, oop, x);
oop p = JNIHandles::resolve(obj);
if (UseCompressedOops) {
if (x != NULL) {
// If there is a heap base pointer, we are obliged to emit a store barrier.
oop_store((narrowOop*)index_oop_from_field_offset_long(p, offset), x);
} else {
narrowOop n = oopDesc::encode_heap_oop_not_null(x);
*(narrowOop*)index_oop_from_field_offset_long(p, offset) = n;
}
} else {
if (x != NULL) {
// If there is a heap base pointer, we are obliged to emit a store barrier.
oop_store((oop*)index_oop_from_field_offset_long(p, offset), x);
} else {
*(oop*)index_oop_from_field_offset_long(p, offset) = x;
}
}
UNSAFE_END
// The normal variants allow a null base pointer with an arbitrary address.
// But if the base pointer is non-null, the offset should make some sense.
// That is, it should be in the range [0, MAX_OBJECT_SIZE].
UNSAFE_ENTRY(jobject, Unsafe_GetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset))
UnsafeWrapper("Unsafe_GetObject");
GET_OOP_FIELD(obj, offset, v)
jobject ret = JNIHandles::make_local(env, v);
#if INCLUDE_ALL_GCS
// We could be accessing the referent field in a reference
// object. If G1 is enabled then we need to register non-null
// referent with the SATB barrier.
if (UseG1GC) {
bool needs_barrier = false;
if (ret != NULL) {
if (offset == java_lang_ref_Reference::referent_offset && obj != NULL) {
oop o = JNIHandles::resolve(obj);
Klass* k = o->klass();
if (InstanceKlass::cast(k)->reference_type() != REF_NONE) {
assert(InstanceKlass::cast(k)->is_subclass_of(SystemDictionary::Reference_klass()), "sanity");
needs_barrier = true;
}
}
}
if (needs_barrier) {
oop referent = JNIHandles::resolve(ret);
G1SATBCardTableModRefBS::enqueue(referent);
}
}
#endif // INCLUDE_ALL_GCS
return ret;
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_SetObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h))
UnsafeWrapper("Unsafe_SetObject");
oop x = JNIHandles::resolve(x_h);
oop p = JNIHandles::resolve(obj);
if (UseCompressedOops) {
oop_store((narrowOop*)index_oop_from_field_offset_long(p, offset), x);
} else {
oop_store((oop*)index_oop_from_field_offset_long(p, offset), x);
}
UNSAFE_END
UNSAFE_ENTRY(jobject, Unsafe_GetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset))
UnsafeWrapper("Unsafe_GetObjectVolatile");
oop p = JNIHandles::resolve(obj);
void* addr = index_oop_from_field_offset_long(p, offset);
volatile oop v;
if (UseCompressedOops) {
volatile narrowOop n = *(volatile narrowOop*) addr;
(void)const_cast<oop&>(v = oopDesc::decode_heap_oop(n));
} else {
(void)const_cast<oop&>(v = *(volatile oop*) addr);
}
OrderAccess::acquire();
return JNIHandles::make_local(env, v);
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_SetObjectVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h))
UnsafeWrapper("Unsafe_SetObjectVolatile");
oop x = JNIHandles::resolve(x_h);
oop p = JNIHandles::resolve(obj);
void* addr = index_oop_from_field_offset_long(p, offset);
OrderAccess::release();
if (UseCompressedOops) {
oop_store((narrowOop*)addr, x);
} else {
oop_store((oop*)addr, x);
}
OrderAccess::fence();
UNSAFE_END
#ifndef SUPPORTS_NATIVE_CX8
// Keep old code for platforms which may not have atomic jlong (8 bytes) instructions
// Volatile long versions must use locks if !VM_Version::supports_cx8().
// support_cx8 is a surrogate for 'supports atomic long memory ops'.
UNSAFE_ENTRY(jlong, Unsafe_GetLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset))
UnsafeWrapper("Unsafe_GetLongVolatile");
{
if (VM_Version::supports_cx8()) {
GET_FIELD_VOLATILE(obj, offset, jlong, v);
return v;
}
else {
Handle p (THREAD, JNIHandles::resolve(obj));
jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
ObjectLocker ol(p, THREAD);
jlong value = *addr;
return value;
}
}
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_SetLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong x))
UnsafeWrapper("Unsafe_SetLongVolatile");
{
if (VM_Version::supports_cx8()) {
SET_FIELD_VOLATILE(obj, offset, jlong, x);
}
else {
Handle p (THREAD, JNIHandles::resolve(obj));
jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
ObjectLocker ol(p, THREAD);
*addr = x;
}
}
UNSAFE_END
#endif // not SUPPORTS_NATIVE_CX8
#define DEFINE_GETSETOOP(jboolean, Boolean) \
\
UNSAFE_ENTRY(jboolean, Unsafe_Get##Boolean##140(JNIEnv *env, jobject unsafe, jobject obj, jint offset)) \
UnsafeWrapper("Unsafe_Get"#Boolean); \
if (obj == NULL) THROW_0(vmSymbols::java_lang_NullPointerException()); \
GET_FIELD(obj, offset, jboolean, v); \
return v; \
UNSAFE_END \
\
UNSAFE_ENTRY(void, Unsafe_Set##Boolean##140(JNIEnv *env, jobject unsafe, jobject obj, jint offset, jboolean x)) \
UnsafeWrapper("Unsafe_Set"#Boolean); \
if (obj == NULL) THROW(vmSymbols::java_lang_NullPointerException()); \
SET_FIELD(obj, offset, jboolean, x); \
UNSAFE_END \
\
UNSAFE_ENTRY(jboolean, Unsafe_Get##Boolean(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) \
UnsafeWrapper("Unsafe_Get"#Boolean); \
GET_FIELD(obj, offset, jboolean, v); \
return v; \
UNSAFE_END \
\
UNSAFE_ENTRY(void, Unsafe_Set##Boolean(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jboolean x)) \
UnsafeWrapper("Unsafe_Set"#Boolean); \
SET_FIELD(obj, offset, jboolean, x); \
UNSAFE_END \
\
// END DEFINE_GETSETOOP.
DEFINE_GETSETOOP(jboolean, Boolean)
DEFINE_GETSETOOP(jbyte, Byte)
DEFINE_GETSETOOP(jshort, Short);
DEFINE_GETSETOOP(jchar, Char);
DEFINE_GETSETOOP(jint, Int);
DEFINE_GETSETOOP(jlong, Long);
DEFINE_GETSETOOP(jfloat, Float);
DEFINE_GETSETOOP(jdouble, Double);
#undef DEFINE_GETSETOOP
#define DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean) \
\
UNSAFE_ENTRY(jboolean, Unsafe_Get##Boolean##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) \
UnsafeWrapper("Unsafe_Get"#Boolean); \
GET_FIELD_VOLATILE(obj, offset, jboolean, v); \
return v; \
UNSAFE_END \
\
UNSAFE_ENTRY(void, Unsafe_Set##Boolean##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jboolean x)) \
UnsafeWrapper("Unsafe_Set"#Boolean); \
SET_FIELD_VOLATILE(obj, offset, jboolean, x); \
UNSAFE_END \
\
// END DEFINE_GETSETOOP_VOLATILE.
DEFINE_GETSETOOP_VOLATILE(jboolean, Boolean)
DEFINE_GETSETOOP_VOLATILE(jbyte, Byte)
DEFINE_GETSETOOP_VOLATILE(jshort, Short);
DEFINE_GETSETOOP_VOLATILE(jchar, Char);
DEFINE_GETSETOOP_VOLATILE(jint, Int);
DEFINE_GETSETOOP_VOLATILE(jfloat, Float);
DEFINE_GETSETOOP_VOLATILE(jdouble, Double);
#ifdef SUPPORTS_NATIVE_CX8
DEFINE_GETSETOOP_VOLATILE(jlong, Long);
#endif
#undef DEFINE_GETSETOOP_VOLATILE
// The non-intrinsified versions of setOrdered just use setVolatile
UNSAFE_ENTRY(void, Unsafe_SetOrderedInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint x))
UnsafeWrapper("Unsafe_SetOrderedInt");
SET_FIELD_VOLATILE(obj, offset, jint, x);
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_SetOrderedObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject x_h))
UnsafeWrapper("Unsafe_SetOrderedObject");
oop x = JNIHandles::resolve(x_h);
oop p = JNIHandles::resolve(obj);
void* addr = index_oop_from_field_offset_long(p, offset);
OrderAccess::release();
if (UseCompressedOops) {
oop_store((narrowOop*)addr, x);
} else {
oop_store((oop*)addr, x);
}
OrderAccess::fence();
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_SetOrderedLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong x))
UnsafeWrapper("Unsafe_SetOrderedLong");
#ifdef SUPPORTS_NATIVE_CX8
SET_FIELD_VOLATILE(obj, offset, jlong, x);
#else
// Keep old code for platforms which may not have atomic long (8 bytes) instructions
{
if (VM_Version::supports_cx8()) {
SET_FIELD_VOLATILE(obj, offset, jlong, x);
}
else {
Handle p (THREAD, JNIHandles::resolve(obj));
jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
ObjectLocker ol(p, THREAD);
*addr = x;
}
}
#endif
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe))
UnsafeWrapper("Unsafe_LoadFence");
OrderAccess::acquire();
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe))
UnsafeWrapper("Unsafe_StoreFence");
OrderAccess::release();
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe))
UnsafeWrapper("Unsafe_FullFence");
OrderAccess::fence();
UNSAFE_END
////// Data in the C heap.
// Note: These do not throw NullPointerException for bad pointers.
// They just crash. Only a oop base pointer can generate a NullPointerException.
//
#define DEFINE_GETSETNATIVE(java_type, Type, native_type) \
\
UNSAFE_ENTRY(java_type, Unsafe_GetNative##Type(JNIEnv *env, jobject unsafe, jlong addr)) \
UnsafeWrapper("Unsafe_GetNative"#Type); \
void* p = addr_from_java(addr); \
JavaThread* t = JavaThread::current(); \
t->set_doing_unsafe_access(true); \
java_type x = *(volatile native_type*)p; \
t->set_doing_unsafe_access(false); \
return x; \
UNSAFE_END \
\
UNSAFE_ENTRY(void, Unsafe_SetNative##Type(JNIEnv *env, jobject unsafe, jlong addr, java_type x)) \
UnsafeWrapper("Unsafe_SetNative"#Type); \
JavaThread* t = JavaThread::current(); \
t->set_doing_unsafe_access(true); \
void* p = addr_from_java(addr); \
*(volatile native_type*)p = x; \
t->set_doing_unsafe_access(false); \
UNSAFE_END \
\
// END DEFINE_GETSETNATIVE.
DEFINE_GETSETNATIVE(jbyte, Byte, signed char)
DEFINE_GETSETNATIVE(jshort, Short, signed short);
DEFINE_GETSETNATIVE(jchar, Char, unsigned short);
DEFINE_GETSETNATIVE(jint, Int, jint);
// no long -- handled specially
DEFINE_GETSETNATIVE(jfloat, Float, float);
DEFINE_GETSETNATIVE(jdouble, Double, double);
#undef DEFINE_GETSETNATIVE
UNSAFE_ENTRY(jlong, Unsafe_GetNativeLong(JNIEnv *env, jobject unsafe, jlong addr))
UnsafeWrapper("Unsafe_GetNativeLong");
JavaThread* t = JavaThread::current();
// We do it this way to avoid problems with access to heap using 64
// bit loads, as jlong in heap could be not 64-bit aligned, and on
// some CPUs (SPARC) it leads to SIGBUS.
t->set_doing_unsafe_access(true);
void* p = addr_from_java(addr);
jlong x;
if (((intptr_t)p & 7) == 0) {
// jlong is aligned, do a volatile access
x = *(volatile jlong*)p;
} else {
jlong_accessor acc;
acc.words[0] = ((volatile jint*)p)[0];
acc.words[1] = ((volatile jint*)p)[1];
x = acc.long_value;
}
t->set_doing_unsafe_access(false);
return x;
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_SetNativeLong(JNIEnv *env, jobject unsafe, jlong addr, jlong x))
UnsafeWrapper("Unsafe_SetNativeLong");
JavaThread* t = JavaThread::current();
// see comment for Unsafe_GetNativeLong
t->set_doing_unsafe_access(true);
void* p = addr_from_java(addr);
if (((intptr_t)p & 7) == 0) {
// jlong is aligned, do a volatile access
*(volatile jlong*)p = x;
} else {
jlong_accessor acc;
acc.long_value = x;
((volatile jint*)p)[0] = acc.words[0];
((volatile jint*)p)[1] = acc.words[1];
}
t->set_doing_unsafe_access(false);
UNSAFE_END
UNSAFE_ENTRY(jlong, Unsafe_GetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr))
UnsafeWrapper("Unsafe_GetNativeAddress");
void* p = addr_from_java(addr);
return addr_to_java(*(void**)p);
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_SetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr, jlong x))
UnsafeWrapper("Unsafe_SetNativeAddress");
void* p = addr_from_java(addr);
*(void**)p = addr_from_java(x);
UNSAFE_END
////// Allocation requests
UNSAFE_ENTRY(jobject, Unsafe_AllocateInstance(JNIEnv *env, jobject unsafe, jclass cls))
UnsafeWrapper("Unsafe_AllocateInstance");
{
ThreadToNativeFromVM ttnfv(thread);
return env->AllocObject(cls);
}
UNSAFE_END
UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory(JNIEnv *env, jobject unsafe, jlong size))
UnsafeWrapper("Unsafe_AllocateMemory");
size_t sz = (size_t)size;
if (sz != (julong)size || size < 0) {
THROW_0(vmSymbols::java_lang_IllegalArgumentException());
}
if (sz == 0) {
return 0;
}
sz = round_to(sz, HeapWordSize);
void* x = os::malloc(sz, mtInternal);
if (x == NULL) {
THROW_0(vmSymbols::java_lang_OutOfMemoryError());
}
//Copy::fill_to_words((HeapWord*)x, sz / HeapWordSize);
return addr_to_java(x);
UNSAFE_END
UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory(JNIEnv *env, jobject unsafe, jlong addr, jlong size))
UnsafeWrapper("Unsafe_ReallocateMemory");
void* p = addr_from_java(addr);
size_t sz = (size_t)size;
if (sz != (julong)size || size < 0) {
THROW_0(vmSymbols::java_lang_IllegalArgumentException());
}
if (sz == 0) {
os::free(p);
return 0;
}
sz = round_to(sz, HeapWordSize);
void* x = (p == NULL) ? os::malloc(sz, mtInternal) : os::realloc(p, sz, mtInternal);
if (x == NULL) {
THROW_0(vmSymbols::java_lang_OutOfMemoryError());
}
return addr_to_java(x);
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_FreeMemory(JNIEnv *env, jobject unsafe, jlong addr))
UnsafeWrapper("Unsafe_FreeMemory");
void* p = addr_from_java(addr);
if (p == NULL) {
return;
}
os::free(p);
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_SetMemory(JNIEnv *env, jobject unsafe, jlong addr, jlong size, jbyte value))
UnsafeWrapper("Unsafe_SetMemory");
size_t sz = (size_t)size;
if (sz != (julong)size || size < 0) {
THROW(vmSymbols::java_lang_IllegalArgumentException());
}
char* p = (char*) addr_from_java(addr);
Copy::fill_to_memory_atomic(p, sz, value);
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_SetMemory2(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value))
UnsafeWrapper("Unsafe_SetMemory");
size_t sz = (size_t)size;
if (sz != (julong)size || size < 0) {
THROW(vmSymbols::java_lang_IllegalArgumentException());
}
oop base = JNIHandles::resolve(obj);
void* p = index_oop_from_field_offset_long(base, offset);
Copy::fill_to_memory_atomic(p, sz, value);
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_CopyMemory(JNIEnv *env, jobject unsafe, jlong srcAddr, jlong dstAddr, jlong size))
UnsafeWrapper("Unsafe_CopyMemory");
if (size == 0) {
return;
}
size_t sz = (size_t)size;
if (sz != (julong)size || size < 0) {
THROW(vmSymbols::java_lang_IllegalArgumentException());
}
void* src = addr_from_java(srcAddr);
void* dst = addr_from_java(dstAddr);
Copy::conjoint_memory_atomic(src, dst, sz);
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_CopyMemory2(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size))
UnsafeWrapper("Unsafe_CopyMemory");
if (size == 0) {
return;
}
size_t sz = (size_t)size;
if (sz != (julong)size || size < 0) {
THROW(vmSymbols::java_lang_IllegalArgumentException());
}
oop srcp = JNIHandles::resolve(srcObj);
oop dstp = JNIHandles::resolve(dstObj);
if (dstp != NULL && !dstp->is_typeArray()) {
// NYI: This works only for non-oop arrays at present.
// Generalizing it would be reasonable, but requires card marking.
// Also, autoboxing a Long from 0L in copyMemory(x,y, 0L,z, n) would be bad.
THROW(vmSymbols::java_lang_IllegalArgumentException());
}
void* src = index_oop_from_field_offset_long(srcp, srcOffset);
void* dst = index_oop_from_field_offset_long(dstp, dstOffset);
Copy::conjoint_memory_atomic(src, dst, sz);
UNSAFE_END
////// Random queries
// See comment at file start about UNSAFE_LEAF
//UNSAFE_LEAF(jint, Unsafe_AddressSize())
UNSAFE_ENTRY(jint, Unsafe_AddressSize(JNIEnv *env, jobject unsafe))
UnsafeWrapper("Unsafe_AddressSize");
return sizeof(void*);
UNSAFE_END
// See comment at file start about UNSAFE_LEAF
//UNSAFE_LEAF(jint, Unsafe_PageSize())
UNSAFE_ENTRY(jint, Unsafe_PageSize(JNIEnv *env, jobject unsafe))
UnsafeWrapper("Unsafe_PageSize");
return os::vm_page_size();
UNSAFE_END
jint find_field_offset(jobject field, int must_be_static, TRAPS) {
if (field == NULL) {
THROW_0(vmSymbols::java_lang_NullPointerException());
}
oop reflected = JNIHandles::resolve_non_null(field);
oop mirror = java_lang_reflect_Field::clazz(reflected);
Klass* k = java_lang_Class::as_Klass(mirror);
int slot = java_lang_reflect_Field::slot(reflected);
int modifiers = java_lang_reflect_Field::modifiers(reflected);
if (must_be_static >= 0) {
int really_is_static = ((modifiers & JVM_ACC_STATIC) != 0);
if (must_be_static != really_is_static) {
THROW_0(vmSymbols::java_lang_IllegalArgumentException());
}
}
int offset = InstanceKlass::cast(k)->field_offset(slot);
return field_offset_from_byte_offset(offset);
}
UNSAFE_ENTRY(jlong, Unsafe_ObjectFieldOffset(JNIEnv *env, jobject unsafe, jobject field))
UnsafeWrapper("Unsafe_ObjectFieldOffset");
return find_field_offset(field, 0, THREAD);
UNSAFE_END
UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset(JNIEnv *env, jobject unsafe, jobject field))
UnsafeWrapper("Unsafe_StaticFieldOffset");
return find_field_offset(field, 1, THREAD);
UNSAFE_END
UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBaseFromField(JNIEnv *env, jobject unsafe, jobject field))
UnsafeWrapper("Unsafe_StaticFieldBase");
// Note: In this VM implementation, a field address is always a short
// offset from the base of a a klass metaobject. Thus, the full dynamic
// range of the return type is never used. However, some implementations
// might put the static field inside an array shared by many classes,
// or even at a fixed address, in which case the address could be quite
// large. In that last case, this function would return NULL, since
// the address would operate alone, without any base pointer.
if (field == NULL) THROW_0(vmSymbols::java_lang_NullPointerException());
oop reflected = JNIHandles::resolve_non_null(field);
oop mirror = java_lang_reflect_Field::clazz(reflected);
int modifiers = java_lang_reflect_Field::modifiers(reflected);
if ((modifiers & JVM_ACC_STATIC) == 0) {
THROW_0(vmSymbols::java_lang_IllegalArgumentException());
}
return JNIHandles::make_local(env, mirror);
UNSAFE_END
//@deprecated
UNSAFE_ENTRY(jint, Unsafe_FieldOffset(JNIEnv *env, jobject unsafe, jobject field))
UnsafeWrapper("Unsafe_FieldOffset");
// tries (but fails) to be polymorphic between static and non-static:
jlong offset = find_field_offset(field, -1, THREAD);
guarantee(offset == (jint)offset, "offset fits in 32 bits");
return (jint)offset;
UNSAFE_END
//@deprecated
UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBaseFromClass(JNIEnv *env, jobject unsafe, jobject clazz))
UnsafeWrapper("Unsafe_StaticFieldBase");
if (clazz == NULL) {
THROW_0(vmSymbols::java_lang_NullPointerException());
}
return JNIHandles::make_local(env, JNIHandles::resolve_non_null(clazz));
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized(JNIEnv *env, jobject unsafe, jobject clazz)) {
UnsafeWrapper("Unsafe_EnsureClassInitialized");
if (clazz == NULL) {
THROW(vmSymbols::java_lang_NullPointerException());
}
oop mirror = JNIHandles::resolve_non_null(clazz);
Klass* klass = java_lang_Class::as_Klass(mirror);
if (klass != NULL && klass->should_be_initialized()) {
InstanceKlass* k = InstanceKlass::cast(klass);
k->initialize(CHECK);
}
}
UNSAFE_END
UNSAFE_ENTRY(jboolean, Unsafe_ShouldBeInitialized(JNIEnv *env, jobject unsafe, jobject clazz)) {
UnsafeWrapper("Unsafe_ShouldBeInitialized");
if (clazz == NULL) {
THROW_(vmSymbols::java_lang_NullPointerException(), false);
}
oop mirror = JNIHandles::resolve_non_null(clazz);
Klass* klass = java_lang_Class::as_Klass(mirror);
if (klass != NULL && klass->should_be_initialized()) {
return true;
}
return false;
}
UNSAFE_END
static void getBaseAndScale(int& base, int& scale, jclass acls, TRAPS) {
if (acls == NULL) {
THROW(vmSymbols::java_lang_NullPointerException());
}
oop mirror = JNIHandles::resolve_non_null(acls);
Klass* k = java_lang_Class::as_Klass(mirror);
if (k == NULL || !k->oop_is_array()) {
THROW(vmSymbols::java_lang_InvalidClassException());
} else if (k->oop_is_objArray()) {
base = arrayOopDesc::base_offset_in_bytes(T_OBJECT);
scale = heapOopSize;
} else if (k->oop_is_typeArray()) {
TypeArrayKlass* tak = TypeArrayKlass::cast(k);
base = tak->array_header_in_bytes();
assert(base == arrayOopDesc::base_offset_in_bytes(tak->element_type()), "array_header_size semantics ok");
scale = (1 << tak->log2_element_size());
} else {
ShouldNotReachHere();
}
}
UNSAFE_ENTRY(jint, Unsafe_ArrayBaseOffset(JNIEnv *env, jobject unsafe, jclass acls))
UnsafeWrapper("Unsafe_ArrayBaseOffset");
int base, scale;
getBaseAndScale(base, scale, acls, CHECK_0);
return field_offset_from_byte_offset(base);
UNSAFE_END
UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale(JNIEnv *env, jobject unsafe, jclass acls))
UnsafeWrapper("Unsafe_ArrayIndexScale");
int base, scale;
getBaseAndScale(base, scale, acls, CHECK_0);
// This VM packs both fields and array elements down to the byte.
// But watch out: If this changes, so that array references for
// a given primitive type (say, T_BOOLEAN) use different memory units
// than fields, this method MUST return zero for such arrays.
// For example, the VM used to store sub-word sized fields in full
// words in the object layout, so that accessors like getByte(Object,int)
// did not really do what one might expect for arrays. Therefore,
// this function used to report a zero scale factor, so that the user
// would know not to attempt to access sub-word array elements.
// // Code for unpacked fields:
// if (scale < wordSize) return 0;
// The following allows for a pretty general fieldOffset cookie scheme,
// but requires it to be linear in byte offset.
return field_offset_from_byte_offset(scale) - field_offset_from_byte_offset(0);
UNSAFE_END
static inline void throw_new(JNIEnv *env, const char *ename) {
char buf[100];
strcpy(buf, "java/lang/");
strcat(buf, ename);
jclass cls = env->FindClass(buf);
char* msg = NULL;
env->ThrowNew(cls, msg);
}
static jclass Unsafe_DefineClass_impl(JNIEnv *env, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd) {
{
// Code lifted from JDK 1.3 ClassLoader.c
jbyte *body;
char *utfName;
jclass result = 0;
char buf[128];
if (UsePerfData) {
ClassLoader::unsafe_defineClassCallCounter()->inc();
}
if (data == NULL) {
throw_new(env, "NullPointerException");
return 0;
}
/* Work around 4153825. malloc crashes on Solaris when passed a
* negative size.
*/
if (length < 0) {
throw_new(env, "ArrayIndexOutOfBoundsException");
return 0;
}
body = NEW_C_HEAP_ARRAY(jbyte, length, mtInternal);
if (body == 0) {
throw_new(env, "OutOfMemoryError");
return 0;
}
env->GetByteArrayRegion(data, offset, length, body);
if (env->ExceptionOccurred())
goto free_body;
if (name != NULL) {
uint len = env->GetStringUTFLength(name);
int unicode_len = env->GetStringLength(name);
if (len >= sizeof(buf)) {
utfName = NEW_C_HEAP_ARRAY(char, len + 1, mtInternal);
if (utfName == NULL) {
throw_new(env, "OutOfMemoryError");
goto free_body;
}
} else {
utfName = buf;
}
env->GetStringUTFRegion(name, 0, unicode_len, utfName);
//VerifyFixClassname(utfName);
for (uint i = 0; i < len; i++) {
if (utfName[i] == '.') utfName[i] = '/';
}
} else {
utfName = NULL;
}
result = JVM_DefineClass(env, utfName, loader, body, length, pd);
if (utfName && utfName != buf)
FREE_C_HEAP_ARRAY(char, utfName, mtInternal);
free_body:
FREE_C_HEAP_ARRAY(jbyte, body, mtInternal);
return result;
}
}
UNSAFE_ENTRY(jclass, Unsafe_DefineClass(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd))
UnsafeWrapper("Unsafe_DefineClass");
{
ThreadToNativeFromVM ttnfv(thread);
return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
}
UNSAFE_END
UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length))
UnsafeWrapper("Unsafe_DefineClass");
{
ThreadToNativeFromVM ttnfv(thread);
int depthFromDefineClass0 = 1;
jclass caller = JVM_GetCallerClass(env, depthFromDefineClass0);
jobject loader = (caller == NULL) ? NULL : JVM_GetClassLoader(env, caller);
jobject pd = (caller == NULL) ? NULL : JVM_GetProtectionDomain(env, caller);
return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd);
}
UNSAFE_END
#define DAC_Args CLS"[B["OBJ
// define a class but do not make it known to the class loader or system dictionary
// - host_class: supplies context for linkage, access control, protection domain, and class loader
// - data: bytes of a class file, a raw memory address (length gives the number of bytes)
// - cp_patches: where non-null entries exist, they replace corresponding CP entries in data
// When you load an anonymous class U, it works as if you changed its name just before loading,
// to a name that you will never use again. Since the name is lost, no other class can directly
// link to any member of U. Just after U is loaded, the only way to use it is reflectively,
// through java.lang.Class methods like Class.newInstance.
// Access checks for linkage sites within U continue to follow the same rules as for named classes.
// The package of an anonymous class is given by the package qualifier on the name under which it was loaded.
// An anonymous class also has special privileges to access any member of its host class.
// This is the main reason why this loading operation is unsafe. The purpose of this is to
// allow language implementations to simulate "open classes"; a host class in effect gets
// new code when an anonymous class is loaded alongside it. A less convenient but more
// standard way to do this is with reflection, which can also be set to ignore access
// restrictions.
// Access into an anonymous class is possible only through reflection. Therefore, there
// are no special access rules for calling into an anonymous class. The relaxed access
// rule for the host class is applied in the opposite direction: A host class reflectively
// access one of its anonymous classes.
// If you load the same bytecodes twice, you get two different classes. You can reload
// the same bytecodes with or without varying CP patches.
// By using the CP patching array, you can have a new anonymous class U2 refer to an older one U1.
// The bytecodes for U2 should refer to U1 by a symbolic name (doesn't matter what the name is).
// The CONSTANT_Class entry for that name can be patched to refer directly to U1.
// This allows, for example, U2 to use U1 as a superclass or super-interface, or as
// an outer class (so that U2 is an anonymous inner class of anonymous U1).
// It is not possible for a named class, or an older anonymous class, to refer by
// name (via its CP) to a newer anonymous class.
// CP patching may also be used to modify (i.e., hack) the names of methods, classes,
// or type descriptors used in the loaded anonymous class.
// Finally, CP patching may be used to introduce "live" objects into the constant pool,
// instead of "dead" strings. A compiled statement like println((Object)"hello") can
// be changed to println(greeting), where greeting is an arbitrary object created before
// the anonymous class is loaded. This is useful in dynamic languages, in which
// various kinds of metaobjects must be introduced as constants into bytecode.
// Note the cast (Object), which tells the verifier to expect an arbitrary object,
// not just a literal string. For such ldc instructions, the verifier uses the
// type Object instead of String, if the loaded constant is not in fact a String.
static instanceKlassHandle
Unsafe_DefineAnonymousClass_impl(JNIEnv *env,
jclass host_class, jbyteArray data, jobjectArray cp_patches_jh,
HeapWord* *temp_alloc,
TRAPS) {
if (UsePerfData) {
ClassLoader::unsafe_defineClassCallCounter()->inc();
}
if (data == NULL) {
THROW_0(vmSymbols::java_lang_NullPointerException());
}
jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length();
jint word_length = (length + sizeof(HeapWord)-1) / sizeof(HeapWord);
HeapWord* body = NEW_C_HEAP_ARRAY(HeapWord, word_length, mtInternal);
if (body == NULL) {
THROW_0(vmSymbols::java_lang_OutOfMemoryError());
}
// caller responsible to free it:
(*temp_alloc) = body;
{
jbyte* array_base = typeArrayOop(JNIHandles::resolve_non_null(data))->byte_at_addr(0);
Copy::conjoint_words((HeapWord*) array_base, body, word_length);
}
u1* class_bytes = (u1*) body;
int class_bytes_length = (int) length;
if (class_bytes_length < 0) class_bytes_length = 0;
if (class_bytes == NULL
|| host_class == NULL
|| length != class_bytes_length)
THROW_0(vmSymbols::java_lang_IllegalArgumentException());
objArrayHandle cp_patches_h;
if (cp_patches_jh != NULL) {
oop p = JNIHandles::resolve_non_null(cp_patches_jh);
if (!p->is_objArray())
THROW_0(vmSymbols::java_lang_IllegalArgumentException());
cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p);
}
KlassHandle host_klass(THREAD, java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class)));
const char* host_source = host_klass->external_name();
Handle host_loader(THREAD, host_klass->class_loader());
Handle host_domain(THREAD, host_klass->protection_domain());
GrowableArray<Handle>* cp_patches = NULL;
if (cp_patches_h.not_null()) {
int alen = cp_patches_h->length();
for (int i = alen-1; i >= 0; i--) {
oop p = cp_patches_h->obj_at(i);
if (p != NULL) {
Handle patch(THREAD, p);
if (cp_patches == NULL)
cp_patches = new GrowableArray<Handle>(i+1, i+1, Handle());
cp_patches->at_put(i, patch);
}
}
}
ClassFileStream st(class_bytes, class_bytes_length, (char*) host_source);
instanceKlassHandle anon_klass;
{
Symbol* no_class_name = NULL;
Klass* anonk = SystemDictionary::parse_stream(no_class_name,
host_loader, host_domain,
&st, host_klass, cp_patches,
CHECK_NULL);
if (anonk == NULL) return NULL;
anon_klass = instanceKlassHandle(THREAD, anonk);
}
return anon_klass;
}
UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh))
{
instanceKlassHandle anon_klass;
jobject res_jh = NULL;
UnsafeWrapper("Unsafe_DefineAnonymousClass");
ResourceMark rm(THREAD);
HeapWord* temp_alloc = NULL;
anon_klass = Unsafe_DefineAnonymousClass_impl(env, host_class, data,
cp_patches_jh,
&temp_alloc, THREAD);
if (anon_klass() != NULL)
res_jh = JNIHandles::make_local(env, anon_klass->java_mirror());
// try/finally clause:
if (temp_alloc != NULL) {
FREE_C_HEAP_ARRAY(HeapWord, temp_alloc, mtInternal);
}
// The anonymous class loader data has been artificially been kept alive to
// this point. The mirror and any instances of this class have to keep
// it alive afterwards.
if (anon_klass() != NULL) {
anon_klass->class_loader_data()->set_keep_alive(false);
}
// let caller initialize it as needed...
return (jclass) res_jh;
}
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_MonitorEnter(JNIEnv *env, jobject unsafe, jobject jobj))
UnsafeWrapper("Unsafe_MonitorEnter");
{
if (jobj == NULL) {
THROW(vmSymbols::java_lang_NullPointerException());
}
Handle obj(thread, JNIHandles::resolve_non_null(jobj));
ObjectSynchronizer::jni_enter(obj, CHECK);
}
UNSAFE_END
UNSAFE_ENTRY(jboolean, Unsafe_TryMonitorEnter(JNIEnv *env, jobject unsafe, jobject jobj))
UnsafeWrapper("Unsafe_TryMonitorEnter");
{
if (jobj == NULL) {
THROW_(vmSymbols::java_lang_NullPointerException(), JNI_FALSE);
}
Handle obj(thread, JNIHandles::resolve_non_null(jobj));
bool res = ObjectSynchronizer::jni_try_enter(obj, CHECK_0);
return (res ? JNI_TRUE : JNI_FALSE);
}
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_MonitorExit(JNIEnv *env, jobject unsafe, jobject jobj))
UnsafeWrapper("Unsafe_MonitorExit");
{
if (jobj == NULL) {
THROW(vmSymbols::java_lang_NullPointerException());
}
Handle obj(THREAD, JNIHandles::resolve_non_null(jobj));
ObjectSynchronizer::jni_exit(obj(), CHECK);
}
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr))
UnsafeWrapper("Unsafe_ThrowException");
{
ThreadToNativeFromVM ttnfv(thread);
env->Throw(thr);
}
UNSAFE_END
// JSR166 ------------------------------------------------------------------
UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h))
UnsafeWrapper("Unsafe_CompareAndSwapObject");
oop x = JNIHandles::resolve(x_h);
oop e = JNIHandles::resolve(e_h);
oop p = JNIHandles::resolve(obj);
HeapWord* addr = (HeapWord *)index_oop_from_field_offset_long(p, offset);
oop res = oopDesc::atomic_compare_exchange_oop(x, addr, e, true);
jboolean success = (res == e);
if (success)
update_barrier_set((void*)addr, x);
return success;
UNSAFE_END
UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x))
UnsafeWrapper("Unsafe_CompareAndSwapInt");
oop p = JNIHandles::resolve(obj);
jint* addr = (jint *) index_oop_from_field_offset_long(p, offset);
return (jint)(Atomic::cmpxchg(x, addr, e)) == e;
UNSAFE_END
UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x))
UnsafeWrapper("Unsafe_CompareAndSwapLong");
Handle p (THREAD, JNIHandles::resolve(obj));
jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset));
if (VM_Version::supports_cx8())
return (jlong)(Atomic::cmpxchg(x, addr, e)) == e;
else {
jboolean success = false;
ObjectLocker ol(p, THREAD);
if (*addr == e) { *addr = x; success = true; }
return success;
}
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time))
UnsafeWrapper("Unsafe_Park");
EventThreadPark event;
#ifndef USDT2
HS_DTRACE_PROBE3(hotspot, thread__park__begin, thread->parker(), (int) isAbsolute, time);
#else /* USDT2 */
HOTSPOT_THREAD_PARK_BEGIN(
(uintptr_t) thread->parker(), (int) isAbsolute, time);
#endif /* USDT2 */
JavaThreadParkedState jtps(thread, time != 0);
thread->parker()->park(isAbsolute != 0, time);
#ifndef USDT2
HS_DTRACE_PROBE1(hotspot, thread__park__end, thread->parker());
#else /* USDT2 */
HOTSPOT_THREAD_PARK_END(
(uintptr_t) thread->parker());
#endif /* USDT2 */
if (event.should_commit()) {
oop obj = thread->current_park_blocker();
event.set_klass((obj != NULL) ? obj->klass() : NULL);
event.set_timeout(time);
event.set_address((obj != NULL) ? (TYPE_ADDRESS) cast_from_oop<uintptr_t>(obj) : 0);
event.commit();
}
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_Unpark(JNIEnv *env, jobject unsafe, jobject jthread))
UnsafeWrapper("Unsafe_Unpark");
Parker* p = NULL;
if (jthread != NULL) {
oop java_thread = JNIHandles::resolve_non_null(jthread);
if (java_thread != NULL) {
jlong lp = java_lang_Thread::park_event(java_thread);
if (lp != 0) {
// This cast is OK even though the jlong might have been read
// non-atomically on 32bit systems, since there, one word will
// always be zero anyway and the value set is always the same
p = (Parker*)addr_from_java(lp);
} else {
// Grab lock if apparently null or using older version of library
MutexLocker mu(Threads_lock);
java_thread = JNIHandles::resolve_non_null(jthread);
if (java_thread != NULL) {
JavaThread* thr = java_lang_Thread::thread(java_thread);
if (thr != NULL) {
p = thr->parker();
if (p != NULL) { // Bind to Java thread for next time.
java_lang_Thread::set_park_event(java_thread, addr_to_java(p));
}
}
}
}
}
}
if (p != NULL) {
#ifndef USDT2
HS_DTRACE_PROBE1(hotspot, thread__unpark, p);
#else /* USDT2 */
HOTSPOT_THREAD_UNPARK(
(uintptr_t) p);
#endif /* USDT2 */
p->unpark();
}
UNSAFE_END
UNSAFE_ENTRY(jint, Unsafe_Loadavg(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem))
UnsafeWrapper("Unsafe_Loadavg");
const int max_nelem = 3;
double la[max_nelem];
jint ret;
typeArrayOop a = typeArrayOop(JNIHandles::resolve_non_null(loadavg));
assert(a->is_typeArray(), "must be type array");
if (nelem < 0 || nelem > max_nelem || a->length() < nelem) {
ThreadToNativeFromVM ttnfv(thread);
throw_new(env, "ArrayIndexOutOfBoundsException");
return -1;
}
ret = os::loadavg(la, nelem);
if (ret == -1) return -1;
// if successful, ret is the number of samples actually retrieved.
assert(ret >= 0 && ret <= max_nelem, "Unexpected loadavg return value");
switch(ret) {
case 3: a->double_at_put(2, (jdouble)la[2]); // fall through
case 2: a->double_at_put(1, (jdouble)la[1]); // fall through
case 1: a->double_at_put(0, (jdouble)la[0]); break;
}
return ret;
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_PrefetchRead(JNIEnv* env, jclass ignored, jobject obj, jlong offset))
UnsafeWrapper("Unsafe_PrefetchRead");
oop p = JNIHandles::resolve(obj);
void* addr = index_oop_from_field_offset_long(p, 0);
Prefetch::read(addr, (intx)offset);
UNSAFE_END
UNSAFE_ENTRY(void, Unsafe_PrefetchWrite(JNIEnv* env, jclass ignored, jobject obj, jlong offset))
UnsafeWrapper("Unsafe_PrefetchWrite");
oop p = JNIHandles::resolve(obj);
void* addr = index_oop_from_field_offset_long(p, 0);
Prefetch::write(addr, (intx)offset);
UNSAFE_END
/// JVM_RegisterUnsafeMethods
#define ADR "J"
#define LANG "Ljava/lang/"
#define OBJ LANG"Object;"
#define CLS LANG"Class;"
#define CTR LANG"reflect/Constructor;"
#define FLD LANG"reflect/Field;"
#define MTH LANG"reflect/Method;"
#define THR LANG"Throwable;"
#define DC0_Args LANG"String;[BII"
#define DC_Args DC0_Args LANG"ClassLoader;" "Ljava/security/ProtectionDomain;"
#define CC (char*) /*cast a literal from (const char*)*/
#define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f)
// define deprecated accessors for compabitility with 1.4.0
#define DECLARE_GETSETOOP_140(Boolean, Z) \
{CC"get"#Boolean, CC"("OBJ"I)"#Z, FN_PTR(Unsafe_Get##Boolean##140)}, \
{CC"put"#Boolean, CC"("OBJ"I"#Z")V", FN_PTR(Unsafe_Set##Boolean##140)}
// Note: In 1.4.1, getObject and kin take both int and long offsets.
#define DECLARE_GETSETOOP_141(Boolean, Z) \
{CC"get"#Boolean, CC"("OBJ"J)"#Z, FN_PTR(Unsafe_Get##Boolean)}, \
{CC"put"#Boolean, CC"("OBJ"J"#Z")V", FN_PTR(Unsafe_Set##Boolean)}
// Note: In 1.5.0, there are volatile versions too
#define DECLARE_GETSETOOP(Boolean, Z) \
{CC"get"#Boolean, CC"("OBJ"J)"#Z, FN_PTR(Unsafe_Get##Boolean)}, \
{CC"put"#Boolean, CC"("OBJ"J"#Z")V", FN_PTR(Unsafe_Set##Boolean)}, \
{CC"get"#Boolean"Volatile", CC"("OBJ"J)"#Z, FN_PTR(Unsafe_Get##Boolean##Volatile)}, \
{CC"put"#Boolean"Volatile", CC"("OBJ"J"#Z")V", FN_PTR(Unsafe_Set##Boolean##Volatile)}
#define DECLARE_GETSETNATIVE(Byte, B) \
{CC"get"#Byte, CC"("ADR")"#B, FN_PTR(Unsafe_GetNative##Byte)}, \
{CC"put"#Byte, CC"("ADR#B")V", FN_PTR(Unsafe_SetNative##Byte)}
// These are the methods for 1.4.0
static JNINativeMethod methods_140[] = {
{CC"getObject", CC"("OBJ"I)"OBJ"", FN_PTR(Unsafe_GetObject140)},
{CC"putObject", CC"("OBJ"I"OBJ")V", FN_PTR(Unsafe_SetObject140)},
DECLARE_GETSETOOP_140(Boolean, Z),
DECLARE_GETSETOOP_140(Byte, B),
DECLARE_GETSETOOP_140(Short, S),
DECLARE_GETSETOOP_140(Char, C),
DECLARE_GETSETOOP_140(Int, I),
DECLARE_GETSETOOP_140(Long, J),
DECLARE_GETSETOOP_140(Float, F),
DECLARE_GETSETOOP_140(Double, D),
DECLARE_GETSETNATIVE(Byte, B),
DECLARE_GETSETNATIVE(Short, S),
DECLARE_GETSETNATIVE(Char, C),
DECLARE_GETSETNATIVE(Int, I),
DECLARE_GETSETNATIVE(Long, J),
DECLARE_GETSETNATIVE(Float, F),
DECLARE_GETSETNATIVE(Double, D),
{CC"getAddress", CC"("ADR")"ADR, FN_PTR(Unsafe_GetNativeAddress)},
{CC"putAddress", CC"("ADR""ADR")V", FN_PTR(Unsafe_SetNativeAddress)},
{CC"allocateMemory", CC"(J)"ADR, FN_PTR(Unsafe_AllocateMemory)},
{CC"reallocateMemory", CC"("ADR"J)"ADR, FN_PTR(Unsafe_ReallocateMemory)},
{CC"freeMemory", CC"("ADR")V", FN_PTR(Unsafe_FreeMemory)},
{CC"fieldOffset", CC"("FLD")I", FN_PTR(Unsafe_FieldOffset)},
{CC"staticFieldBase", CC"("CLS")"OBJ, FN_PTR(Unsafe_StaticFieldBaseFromClass)},
{CC"ensureClassInitialized",CC"("CLS")V", FN_PTR(Unsafe_EnsureClassInitialized)},
{CC"arrayBaseOffset", CC"("CLS")I", FN_PTR(Unsafe_ArrayBaseOffset)},
{CC"arrayIndexScale", CC"("CLS")I", FN_PTR(Unsafe_ArrayIndexScale)},
{CC"addressSize", CC"()I", FN_PTR(Unsafe_AddressSize)},
{CC"pageSize", CC"()I", FN_PTR(Unsafe_PageSize)},
{CC"defineClass", CC"("DC0_Args")"CLS, FN_PTR(Unsafe_DefineClass0)},
{CC"defineClass", CC"("DC_Args")"CLS, FN_PTR(Unsafe_DefineClass)},
{CC"allocateInstance", CC"("CLS")"OBJ, FN_PTR(Unsafe_AllocateInstance)},
{CC"monitorEnter", CC"("OBJ")V", FN_PTR(Unsafe_MonitorEnter)},
{CC"monitorExit", CC"("OBJ")V", FN_PTR(Unsafe_MonitorExit)},
{CC"throwException", CC"("THR")V", FN_PTR(Unsafe_ThrowException)}
};
// These are the methods prior to the JSR 166 changes in 1.5.0
static JNINativeMethod methods_141[] = {
{CC"getObject", CC"("OBJ"J)"OBJ"", FN_PTR(Unsafe_GetObject)},
{CC"putObject", CC"("OBJ"J"OBJ")V", FN_PTR(Unsafe_SetObject)},
DECLARE_GETSETOOP_141(Boolean, Z),
DECLARE_GETSETOOP_141(Byte, B),
DECLARE_GETSETOOP_141(Short, S),
DECLARE_GETSETOOP_141(Char, C),
DECLARE_GETSETOOP_141(Int, I),
DECLARE_GETSETOOP_141(Long, J),
DECLARE_GETSETOOP_141(Float, F),
DECLARE_GETSETOOP_141(Double, D),
DECLARE_GETSETNATIVE(Byte, B),
DECLARE_GETSETNATIVE(Short, S),
DECLARE_GETSETNATIVE(Char, C),
DECLARE_GETSETNATIVE(Int, I),
DECLARE_GETSETNATIVE(Long, J),
DECLARE_GETSETNATIVE(Float, F),
DECLARE_GETSETNATIVE(Double, D),
{CC"getAddress", CC"("ADR")"ADR, FN_PTR(Unsafe_GetNativeAddress)},
{CC"putAddress", CC"("ADR""ADR")V", FN_PTR(Unsafe_SetNativeAddress)},
{CC"allocateMemory", CC"(J)"ADR, FN_PTR(Unsafe_AllocateMemory)},
{CC"reallocateMemory", CC"("ADR"J)"ADR, FN_PTR(Unsafe_ReallocateMemory)},
{CC"freeMemory", CC"("ADR")V", FN_PTR(Unsafe_FreeMemory)},
{CC"objectFieldOffset", CC"("FLD")J", FN_PTR(Unsafe_ObjectFieldOffset)},
{CC"staticFieldOffset", CC"("FLD")J", FN_PTR(Unsafe_StaticFieldOffset)},
{CC"staticFieldBase", CC"("FLD")"OBJ, FN_PTR(Unsafe_StaticFieldBaseFromField)},
{CC"ensureClassInitialized",CC"("CLS")V", FN_PTR(Unsafe_EnsureClassInitialized)},
{CC"arrayBaseOffset", CC"("CLS")I", FN_PTR(Unsafe_ArrayBaseOffset)},
{CC"arrayIndexScale", CC"("CLS")I", FN_PTR(Unsafe_ArrayIndexScale)},
{CC"addressSize", CC"()I", FN_PTR(Unsafe_AddressSize)},
{CC"pageSize", CC"()I", FN_PTR(Unsafe_PageSize)},
{CC"defineClass", CC"("DC0_Args")"CLS, FN_PTR(Unsafe_DefineClass0)},
{CC"defineClass", CC"("DC_Args")"CLS, FN_PTR(Unsafe_DefineClass)},
{CC"allocateInstance", CC"("CLS")"OBJ, FN_PTR(Unsafe_AllocateInstance)},
{CC"monitorEnter", CC"("OBJ")V", FN_PTR(Unsafe_MonitorEnter)},
{CC"monitorExit", CC"("OBJ")V", FN_PTR(Unsafe_MonitorExit)},
{CC"throwException", CC"("THR")V", FN_PTR(Unsafe_ThrowException)}
};
// These are the methods prior to the JSR 166 changes in 1.6.0
static JNINativeMethod methods_15[] = {
{CC"getObject", CC"("OBJ"J)"OBJ"", FN_PTR(Unsafe_GetObject)},
{CC"putObject", CC"("OBJ"J"OBJ")V", FN_PTR(Unsafe_SetObject)},
{CC"getObjectVolatile",CC"("OBJ"J)"OBJ"", FN_PTR(Unsafe_GetObjectVolatile)},
{CC"putObjectVolatile",CC"("OBJ"J"OBJ")V", FN_PTR(Unsafe_SetObjectVolatile)},
DECLARE_GETSETOOP(Boolean, Z),
DECLARE_GETSETOOP(Byte, B),
DECLARE_GETSETOOP(Short, S),
DECLARE_GETSETOOP(Char, C),
DECLARE_GETSETOOP(Int, I),
DECLARE_GETSETOOP(Long, J),
DECLARE_GETSETOOP(Float, F),
DECLARE_GETSETOOP(Double, D),
DECLARE_GETSETNATIVE(Byte, B),
DECLARE_GETSETNATIVE(Short, S),
DECLARE_GETSETNATIVE(Char, C),
DECLARE_GETSETNATIVE(Int, I),
DECLARE_GETSETNATIVE(Long, J),
DECLARE_GETSETNATIVE(Float, F),
DECLARE_GETSETNATIVE(Double, D),
{CC"getAddress", CC"("ADR")"ADR, FN_PTR(Unsafe_GetNativeAddress)},
{CC"putAddress", CC"("ADR""ADR")V", FN_PTR(Unsafe_SetNativeAddress)},
{CC"allocateMemory", CC"(J)"ADR, FN_PTR(Unsafe_AllocateMemory)},
{CC"reallocateMemory", CC"("ADR"J)"ADR, FN_PTR(Unsafe_ReallocateMemory)},
{CC"freeMemory", CC"("ADR")V", FN_PTR(Unsafe_FreeMemory)},
{CC"objectFieldOffset", CC"("FLD")J", FN_PTR(Unsafe_ObjectFieldOffset)},
{CC"staticFieldOffset", CC"("FLD")J", FN_PTR(Unsafe_StaticFieldOffset)},
{CC"staticFieldBase", CC"("FLD")"OBJ, FN_PTR(Unsafe_StaticFieldBaseFromField)},
{CC"ensureClassInitialized",CC"("CLS")V", FN_PTR(Unsafe_EnsureClassInitialized)},
{CC"arrayBaseOffset", CC"("CLS")I", FN_PTR(Unsafe_ArrayBaseOffset)},
{CC"arrayIndexScale", CC"("CLS")I", FN_PTR(Unsafe_ArrayIndexScale)},
{CC"addressSize", CC"()I", FN_PTR(Unsafe_AddressSize)},
{CC"pageSize", CC"()I", FN_PTR(Unsafe_PageSize)},
{CC"defineClass", CC"("DC0_Args")"CLS, FN_PTR(Unsafe_DefineClass0)},
{CC"defineClass", CC"("DC_Args")"CLS, FN_PTR(Unsafe_DefineClass)},
{CC"allocateInstance", CC"("CLS")"OBJ, FN_PTR(Unsafe_AllocateInstance)},
{CC"monitorEnter", CC"("OBJ")V", FN_PTR(Unsafe_MonitorEnter)},
{CC"monitorExit", CC"("OBJ")V", FN_PTR(Unsafe_MonitorExit)},
{CC"throwException", CC"("THR")V", FN_PTR(Unsafe_ThrowException)},
{CC"compareAndSwapObject", CC"("OBJ"J"OBJ""OBJ")Z", FN_PTR(Unsafe_CompareAndSwapObject)},
{CC"compareAndSwapInt", CC"("OBJ"J""I""I"")Z", FN_PTR(Unsafe_CompareAndSwapInt)},
{CC"compareAndSwapLong", CC"("OBJ"J""J""J"")Z", FN_PTR(Unsafe_CompareAndSwapLong)},
{CC"park", CC"(ZJ)V", FN_PTR(Unsafe_Park)},
{CC"unpark", CC"("OBJ")V", FN_PTR(Unsafe_Unpark)}
};
// These are the methods for 1.6.0 and 1.7.0
static JNINativeMethod methods_16[] = {
{CC"getObject", CC"("OBJ"J)"OBJ"", FN_PTR(Unsafe_GetObject)},
{CC"putObject", CC"("OBJ"J"OBJ")V", FN_PTR(Unsafe_SetObject)},
{CC"getObjectVolatile",CC"("OBJ"J)"OBJ"", FN_PTR(Unsafe_GetObjectVolatile)},
{CC"putObjectVolatile",CC"("OBJ"J"OBJ")V", FN_PTR(Unsafe_SetObjectVolatile)},
DECLARE_GETSETOOP(Boolean, Z),
DECLARE_GETSETOOP(Byte, B),
DECLARE_GETSETOOP(Short, S),
DECLARE_GETSETOOP(Char, C),
DECLARE_GETSETOOP(Int, I),
DECLARE_GETSETOOP(Long, J),
DECLARE_GETSETOOP(Float, F),
DECLARE_GETSETOOP(Double, D),
DECLARE_GETSETNATIVE(Byte, B),
DECLARE_GETSETNATIVE(Short, S),
DECLARE_GETSETNATIVE(Char, C),
DECLARE_GETSETNATIVE(Int, I),
DECLARE_GETSETNATIVE(Long, J),
DECLARE_GETSETNATIVE(Float, F),
DECLARE_GETSETNATIVE(Double, D),
{CC"getAddress", CC"("ADR")"ADR, FN_PTR(Unsafe_GetNativeAddress)},
{CC"putAddress", CC"("ADR""ADR")V", FN_PTR(Unsafe_SetNativeAddress)},
{CC"allocateMemory", CC"(J)"ADR, FN_PTR(Unsafe_AllocateMemory)},
{CC"reallocateMemory", CC"("ADR"J)"ADR, FN_PTR(Unsafe_ReallocateMemory)},
{CC"freeMemory", CC"("ADR")V", FN_PTR(Unsafe_FreeMemory)},
{CC"objectFieldOffset", CC"("FLD")J", FN_PTR(Unsafe_ObjectFieldOffset)},
{CC"staticFieldOffset", CC"("FLD")J", FN_PTR(Unsafe_StaticFieldOffset)},
{CC"staticFieldBase", CC"("FLD")"OBJ, FN_PTR(Unsafe_StaticFieldBaseFromField)},
{CC"ensureClassInitialized",CC"("CLS")V", FN_PTR(Unsafe_EnsureClassInitialized)},
{CC"arrayBaseOffset", CC"("CLS")I", FN_PTR(Unsafe_ArrayBaseOffset)},
{CC"arrayIndexScale", CC"("CLS")I", FN_PTR(Unsafe_ArrayIndexScale)},
{CC"addressSize", CC"()I", FN_PTR(Unsafe_AddressSize)},
{CC"pageSize", CC"()I", FN_PTR(Unsafe_PageSize)},
{CC"defineClass", CC"("DC0_Args")"CLS, FN_PTR(Unsafe_DefineClass0)},
{CC"defineClass", CC"("DC_Args")"CLS, FN_PTR(Unsafe_DefineClass)},
{CC"allocateInstance", CC"("CLS")"OBJ, FN_PTR(Unsafe_AllocateInstance)},
{CC"monitorEnter", CC"("OBJ")V", FN_PTR(Unsafe_MonitorEnter)},
{CC"monitorExit", CC"("OBJ")V", FN_PTR(Unsafe_MonitorExit)},
{CC"tryMonitorEnter", CC"("OBJ")Z", FN_PTR(Unsafe_TryMonitorEnter)},
{CC"throwException", CC"("THR")V", FN_PTR(Unsafe_ThrowException)},
{CC"compareAndSwapObject", CC"("OBJ"J"OBJ""OBJ")Z", FN_PTR(Unsafe_CompareAndSwapObject)},
{CC"compareAndSwapInt", CC"("OBJ"J""I""I"")Z", FN_PTR(Unsafe_CompareAndSwapInt)},
{CC"compareAndSwapLong", CC"("OBJ"J""J""J"")Z", FN_PTR(Unsafe_CompareAndSwapLong)},
{CC"putOrderedObject", CC"("OBJ"J"OBJ")V", FN_PTR(Unsafe_SetOrderedObject)},
{CC"putOrderedInt", CC"("OBJ"JI)V", FN_PTR(Unsafe_SetOrderedInt)},
{CC"putOrderedLong", CC"("OBJ"JJ)V", FN_PTR(Unsafe_SetOrderedLong)},
{CC"park", CC"(ZJ)V", FN_PTR(Unsafe_Park)},
{CC"unpark", CC"("OBJ")V", FN_PTR(Unsafe_Unpark)}
};
// These are the methods for 1.8.0
static JNINativeMethod methods_18[] = {
{CC"getObject", CC"("OBJ"J)"OBJ"", FN_PTR(Unsafe_GetObject)},
{CC"putObject", CC"("OBJ"J"OBJ")V", FN_PTR(Unsafe_SetObject)},
{CC"getObjectVolatile",CC"("OBJ"J)"OBJ"", FN_PTR(Unsafe_GetObjectVolatile)},
{CC"putObjectVolatile",CC"("OBJ"J"OBJ")V", FN_PTR(Unsafe_SetObjectVolatile)},
DECLARE_GETSETOOP(Boolean, Z),
DECLARE_GETSETOOP(Byte, B),
DECLARE_GETSETOOP(Short, S),
DECLARE_GETSETOOP(Char, C),
DECLARE_GETSETOOP(Int, I),
DECLARE_GETSETOOP(Long, J),
DECLARE_GETSETOOP(Float, F),
DECLARE_GETSETOOP(Double, D),
DECLARE_GETSETNATIVE(Byte, B),
DECLARE_GETSETNATIVE(Short, S),
DECLARE_GETSETNATIVE(Char, C),
DECLARE_GETSETNATIVE(Int, I),
DECLARE_GETSETNATIVE(Long, J),
DECLARE_GETSETNATIVE(Float, F),
DECLARE_GETSETNATIVE(Double, D),
{CC"getAddress", CC"("ADR")"ADR, FN_PTR(Unsafe_GetNativeAddress)},
{CC"putAddress", CC"("ADR""ADR")V", FN_PTR(Unsafe_SetNativeAddress)},
{CC"allocateMemory", CC"(J)"ADR, FN_PTR(Unsafe_AllocateMemory)},
{CC"reallocateMemory", CC"("ADR"J)"ADR, FN_PTR(Unsafe_ReallocateMemory)},
{CC"freeMemory", CC"("ADR")V", FN_PTR(Unsafe_FreeMemory)},
{CC"objectFieldOffset", CC"("FLD")J", FN_PTR(Unsafe_ObjectFieldOffset)},
{CC"staticFieldOffset", CC"("FLD")J", FN_PTR(Unsafe_StaticFieldOffset)},
{CC"staticFieldBase", CC"("FLD")"OBJ, FN_PTR(Unsafe_StaticFieldBaseFromField)},
{CC"ensureClassInitialized",CC"("CLS")V", FN_PTR(Unsafe_EnsureClassInitialized)},
{CC"arrayBaseOffset", CC"("CLS")I", FN_PTR(Unsafe_ArrayBaseOffset)},
{CC"arrayIndexScale", CC"("CLS")I", FN_PTR(Unsafe_ArrayIndexScale)},
{CC"addressSize", CC"()I", FN_PTR(Unsafe_AddressSize)},
{CC"pageSize", CC"()I", FN_PTR(Unsafe_PageSize)},
{CC"defineClass", CC"("DC_Args")"CLS, FN_PTR(Unsafe_DefineClass)},
{CC"allocateInstance", CC"("CLS")"OBJ, FN_PTR(Unsafe_AllocateInstance)},
{CC"monitorEnter", CC"("OBJ")V", FN_PTR(Unsafe_MonitorEnter)},
{CC"monitorExit", CC"("OBJ")V", FN_PTR(Unsafe_MonitorExit)},
{CC"tryMonitorEnter", CC"("OBJ")Z", FN_PTR(Unsafe_TryMonitorEnter)},
{CC"throwException", CC"("THR")V", FN_PTR(Unsafe_ThrowException)},
{CC"compareAndSwapObject", CC"("OBJ"J"OBJ""OBJ")Z", FN_PTR(Unsafe_CompareAndSwapObject)},
{CC"compareAndSwapInt", CC"("OBJ"J""I""I"")Z", FN_PTR(Unsafe_CompareAndSwapInt)},
{CC"compareAndSwapLong", CC"("OBJ"J""J""J"")Z", FN_PTR(Unsafe_CompareAndSwapLong)},
{CC"putOrderedObject", CC"("OBJ"J"OBJ")V", FN_PTR(Unsafe_SetOrderedObject)},
{CC"putOrderedInt", CC"("OBJ"JI)V", FN_PTR(Unsafe_SetOrderedInt)},
{CC"putOrderedLong", CC"("OBJ"JJ)V", FN_PTR(Unsafe_SetOrderedLong)},
{CC"park", CC"(ZJ)V", FN_PTR(Unsafe_Park)},
{CC"unpark", CC"("OBJ")V", FN_PTR(Unsafe_Unpark)}
};
JNINativeMethod loadavg_method[] = {
{CC"getLoadAverage", CC"([DI)I", FN_PTR(Unsafe_Loadavg)}
};
JNINativeMethod prefetch_methods[] = {
{CC"prefetchRead", CC"("OBJ"J)V", FN_PTR(Unsafe_PrefetchRead)},
{CC"prefetchWrite", CC"("OBJ"J)V", FN_PTR(Unsafe_PrefetchWrite)},
{CC"prefetchReadStatic", CC"("OBJ"J)V", FN_PTR(Unsafe_PrefetchRead)},
{CC"prefetchWriteStatic",CC"("OBJ"J)V", FN_PTR(Unsafe_PrefetchWrite)}
};
JNINativeMethod memcopy_methods_17[] = {
{CC"copyMemory", CC"("OBJ"J"OBJ"JJ)V", FN_PTR(Unsafe_CopyMemory2)},
{CC"setMemory", CC"("OBJ"JJB)V", FN_PTR(Unsafe_SetMemory2)}
};
JNINativeMethod memcopy_methods_15[] = {
{CC"setMemory", CC"("ADR"JB)V", FN_PTR(Unsafe_SetMemory)},
{CC"copyMemory", CC"("ADR ADR"J)V", FN_PTR(Unsafe_CopyMemory)}
};
JNINativeMethod anonk_methods[] = {
{CC"defineAnonymousClass", CC"("DAC_Args")"CLS, FN_PTR(Unsafe_DefineAnonymousClass)},
};
JNINativeMethod lform_methods[] = {
{CC"shouldBeInitialized",CC"("CLS")Z", FN_PTR(Unsafe_ShouldBeInitialized)},
};
JNINativeMethod fence_methods[] = {
{CC"loadFence", CC"()V", FN_PTR(Unsafe_LoadFence)},
{CC"storeFence", CC"()V", FN_PTR(Unsafe_StoreFence)},
{CC"fullFence", CC"()V", FN_PTR(Unsafe_FullFence)},
};
#undef CC
#undef FN_PTR
#undef ADR
#undef LANG
#undef OBJ
#undef CLS
#undef CTR
#undef FLD
#undef MTH
#undef THR
#undef DC0_Args
#undef DC_Args
#undef DECLARE_GETSETOOP
#undef DECLARE_GETSETNATIVE
/**
* Helper method to register native methods.
*/
static bool register_natives(const char* message, JNIEnv* env, jclass clazz, const JNINativeMethod* methods, jint nMethods) {
int status = env->RegisterNatives(clazz, methods, nMethods);
if (status < 0 || env->ExceptionOccurred()) {
if (PrintMiscellaneous && (Verbose || WizardMode)) {
tty->print_cr("Unsafe: failed registering %s", message);
}
env->ExceptionClear();
return false;
} else {
if (PrintMiscellaneous && (Verbose || WizardMode)) {
tty->print_cr("Unsafe: successfully registered %s", message);
}
return true;
}
}
// This one function is exported, used by NativeLookup.
// The Unsafe_xxx functions above are called only from the interpreter.
// The optimizer looks at names and signatures to recognize
// individual functions.
JVM_ENTRY(void, JVM_RegisterUnsafeMethods(JNIEnv *env, jclass unsafecls))
UnsafeWrapper("JVM_RegisterUnsafeMethods");
{
ThreadToNativeFromVM ttnfv(thread);
// Unsafe methods
{
bool success = false;
// We need to register the 1.6 methods first because the 1.8 methods would register fine on 1.7 and 1.6
if (!success) {
success = register_natives("1.6 methods", env, unsafecls, methods_16, sizeof(methods_16)/sizeof(JNINativeMethod));
}
if (!success) {
success = register_natives("1.8 methods", env, unsafecls, methods_18, sizeof(methods_18)/sizeof(JNINativeMethod));
}
if (!success) {
success = register_natives("1.5 methods", env, unsafecls, methods_15, sizeof(methods_15)/sizeof(JNINativeMethod));
}
if (!success) {
success = register_natives("1.4.1 methods", env, unsafecls, methods_141, sizeof(methods_141)/sizeof(JNINativeMethod));
}
if (!success) {
success = register_natives("1.4.0 methods", env, unsafecls, methods_140, sizeof(methods_140)/sizeof(JNINativeMethod));
}
guarantee(success, "register unsafe natives");
}
// Unsafe.getLoadAverage
register_natives("1.6 loadavg method", env, unsafecls, loadavg_method, sizeof(loadavg_method)/sizeof(JNINativeMethod));
// Prefetch methods
register_natives("1.6 prefetch methods", env, unsafecls, prefetch_methods, sizeof(prefetch_methods)/sizeof(JNINativeMethod));
// Memory copy methods
{
bool success = false;
if (!success) {
success = register_natives("1.7 memory copy methods", env, unsafecls, memcopy_methods_17, sizeof(memcopy_methods_17)/sizeof(JNINativeMethod));
}
if (!success) {
success = register_natives("1.5 memory copy methods", env, unsafecls, memcopy_methods_15, sizeof(memcopy_methods_15)/sizeof(JNINativeMethod));
}
}
// Unsafe.defineAnonymousClass
if (EnableInvokeDynamic) {
register_natives("1.7 define anonymous class method", env, unsafecls, anonk_methods, sizeof(anonk_methods)/sizeof(JNINativeMethod));
}
// Unsafe.shouldBeInitialized
if (EnableInvokeDynamic) {
register_natives("1.7 LambdaForm support", env, unsafecls, lform_methods, sizeof(lform_methods)/sizeof(JNINativeMethod));
}
// Fence methods
register_natives("1.8 fence methods", env, unsafecls, fence_methods, sizeof(fence_methods)/sizeof(JNINativeMethod));
}



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JVM中unsafe.cpp源码