| /* |
| * Copyright (c) 2000, 2016, 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/classFileStream.hpp" |
| #include "classfile/vmSymbols.hpp" |
| #include "memory/allocation.inline.hpp" |
| #include "oops/objArrayOop.inline.hpp" |
| #include "oops/oop.inline.hpp" |
| #include "prims/jni.h" |
| #include "prims/jvm.h" |
| #include "prims/unsafe.hpp" |
| #include "runtime/atomic.inline.hpp" |
| #include "runtime/globals.hpp" |
| #include "runtime/interfaceSupport.hpp" |
| #include "runtime/orderAccess.inline.hpp" |
| #include "runtime/reflection.hpp" |
| #include "runtime/vm_version.hpp" |
| #include "services/threadService.hpp" |
| #include "trace/tracing.hpp" |
| #include "utilities/copy.hpp" |
| #include "utilities/dtrace.hpp" |
| #include "utilities/macros.hpp" |
| #if INCLUDE_ALL_GCS |
| #include "gc/g1/g1SATBCardTableModRefBS.hpp" |
| #endif // INCLUDE_ALL_GCS |
| |
| /** |
| * Implementation of the jdk.internal.misc.Unsafe class |
| */ |
| |
| |
| #define MAX_OBJECT_SIZE \ |
| ( arrayOopDesc::header_size(T_DOUBLE) * HeapWordSize \ |
| + ((julong)max_jint * sizeof(double)) ) |
| |
| |
| #define UNSAFE_ENTRY(result_type, header) \ |
| JVM_ENTRY(static result_type, header) |
| |
| #define UNSAFE_LEAF(result_type, header) \ |
| JVM_LEAF(static result_type, header) |
| |
| #define UNSAFE_END JVM_END |
| |
| |
| static 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; |
| } |
| |
| static 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. |
| |
| static inline jlong field_offset_to_byte_offset(jlong field_offset) { |
| return field_offset; |
| } |
| |
| static inline jlong field_offset_from_byte_offset(jlong byte_offset) { |
| return byte_offset; |
| } |
| |
| static 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, "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; |
| } |
| |
| |
| ///// 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); \ |
| if (support_IRIW_for_not_multiple_copy_atomic_cpu) { \ |
| OrderAccess::fence(); \ |
| } \ |
| 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); |
| |
| |
| // Get/SetObject must be special-cased, since it works with handles. |
| |
| // These functions 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)) { |
| 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); |
| } |
| |
| 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)) { |
| 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)) { |
| 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)) { |
| 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(jobject, Unsafe_GetUncompressedObject(JNIEnv *env, jobject unsafe, jlong addr)) { |
| oop v = *(oop*) (address) addr; |
| |
| return JNIHandles::make_local(env, v); |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(jclass, Unsafe_GetJavaMirror(JNIEnv *env, jobject unsafe, jlong metaspace_klass)) { |
| Klass* klass = (Klass*) (address) metaspace_klass; |
| |
| return (jclass) JNIHandles::make_local(klass->java_mirror()); |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(jlong, Unsafe_GetKlassPointer(JNIEnv *env, jobject unsafe, jobject obj)) { |
| oop o = JNIHandles::resolve(obj); |
| jlong klass = (jlong) (address) o->klass(); |
| |
| return klass; |
| } UNSAFE_END |
| |
| #ifndef SUPPORTS_NATIVE_CX8 |
| |
| // VM_Version::supports_cx8() is a surrogate for 'supports atomic long memory ops'. |
| // |
| // On platforms which do not support atomic compare-and-swap of jlong (8 byte) |
| // values we have to use a lock-based scheme to enforce atomicity. This has to be |
| // applied to all Unsafe operations that set the value of a jlong field. Even so |
| // the compareAndSwapLong operation will not be atomic with respect to direct stores |
| // to the field from Java code. It is important therefore that any Java code that |
| // utilizes these Unsafe jlong operations does not perform direct stores. To permit |
| // direct loads of the field from Java code we must also use Atomic::store within the |
| // locked regions. And for good measure, in case there are direct stores, we also |
| // employ Atomic::load within those regions. Note that the field in question must be |
| // volatile and so must have atomic load/store accesses applied at the Java level. |
| // |
| // The locking scheme could utilize a range of strategies for controlling the locking |
| // granularity: from a lock per-field through to a single global lock. The latter is |
| // the simplest and is used for the current implementation. Note that the Java object |
| // that contains the field, can not, in general, be used for locking. To do so can lead |
| // to deadlocks as we may introduce locking into what appears to the Java code to be a |
| // lock-free path. |
| // |
| // As all the locked-regions are very short and themselves non-blocking we can treat |
| // them as leaf routines and elide safepoint checks (ie we don't perform any thread |
| // state transitions even when blocking for the lock). Note that if we do choose to |
| // add safepoint checks and thread state transitions, we must ensure that we calculate |
| // the address of the field _after_ we have acquired the lock, else the object may have |
| // been moved by the GC |
| |
| UNSAFE_ENTRY(jlong, Unsafe_GetLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { |
| 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)); |
| MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag); |
| jlong value = Atomic::load(addr); |
| return value; |
| } |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(void, Unsafe_SetLongVolatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong x)) { |
| 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)); |
| MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag); |
| Atomic::store(x, addr); |
| } |
| } UNSAFE_END |
| |
| #endif // not SUPPORTS_NATIVE_CX8 |
| |
| UNSAFE_LEAF(jboolean, Unsafe_isBigEndian0(JNIEnv *env, jobject unsafe)) { |
| #ifdef VM_LITTLE_ENDIAN |
| return false; |
| #else |
| return true; |
| #endif |
| } UNSAFE_END |
| |
| UNSAFE_LEAF(jint, Unsafe_unalignedAccess0(JNIEnv *env, jobject unsafe)) { |
| return UseUnalignedAccesses; |
| } UNSAFE_END |
| |
| #define DEFINE_GETSETOOP(java_type, Type) \ |
| \ |
| UNSAFE_ENTRY(java_type, Unsafe_Get##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \ |
| GET_FIELD(obj, offset, java_type, v); \ |
| return v; \ |
| } UNSAFE_END \ |
| \ |
| UNSAFE_ENTRY(void, Unsafe_Set##Type(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \ |
| SET_FIELD(obj, offset, java_type, 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(java_type, Type) \ |
| \ |
| UNSAFE_ENTRY(java_type, Unsafe_Get##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset)) { \ |
| GET_FIELD_VOLATILE(obj, offset, java_type, v); \ |
| return v; \ |
| } UNSAFE_END \ |
| \ |
| UNSAFE_ENTRY(void, Unsafe_Set##Type##Volatile(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, java_type x)) { \ |
| SET_FIELD_VOLATILE(obj, offset, java_type, 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 |
| |
| UNSAFE_LEAF(void, Unsafe_LoadFence(JNIEnv *env, jobject unsafe)) { |
| OrderAccess::acquire(); |
| } UNSAFE_END |
| |
| UNSAFE_LEAF(void, Unsafe_StoreFence(JNIEnv *env, jobject unsafe)) { |
| OrderAccess::release(); |
| } UNSAFE_END |
| |
| UNSAFE_LEAF(void, Unsafe_FullFence(JNIEnv *env, jobject unsafe)) { |
| 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)) { \ |
| 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)) { \ |
| 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)) { |
| 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 (is_ptr_aligned(p, sizeof(jlong)) == 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)) { |
| JavaThread* t = JavaThread::current(); |
| // see comment for Unsafe_GetNativeLong |
| t->set_doing_unsafe_access(true); |
| void* p = addr_from_java(addr); |
| |
| if (is_ptr_aligned(p, sizeof(jlong))) { |
| // 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_LEAF(jlong, Unsafe_GetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr)) { |
| void* p = addr_from_java(addr); |
| |
| return addr_to_java(*(void**)p); |
| } UNSAFE_END |
| |
| UNSAFE_LEAF(void, Unsafe_SetNativeAddress(JNIEnv *env, jobject unsafe, jlong addr, jlong x)) { |
| 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)) { |
| ThreadToNativeFromVM ttnfv(thread); |
| return env->AllocObject(cls); |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(jlong, Unsafe_AllocateMemory0(JNIEnv *env, jobject unsafe, jlong size)) { |
| size_t sz = (size_t)size; |
| |
| sz = round_to(sz, HeapWordSize); |
| void* x = os::malloc(sz, mtInternal); |
| |
| return addr_to_java(x); |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(jlong, Unsafe_ReallocateMemory0(JNIEnv *env, jobject unsafe, jlong addr, jlong size)) { |
| void* p = addr_from_java(addr); |
| size_t sz = (size_t)size; |
| sz = round_to(sz, HeapWordSize); |
| |
| void* x = os::realloc(p, sz, mtInternal); |
| |
| return addr_to_java(x); |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(void, Unsafe_FreeMemory0(JNIEnv *env, jobject unsafe, jlong addr)) { |
| void* p = addr_from_java(addr); |
| |
| os::free(p); |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(void, Unsafe_SetMemory0(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong size, jbyte value)) { |
| size_t sz = (size_t)size; |
| |
| 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_CopyMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size)) { |
| size_t sz = (size_t)size; |
| |
| oop srcp = JNIHandles::resolve(srcObj); |
| oop dstp = JNIHandles::resolve(dstObj); |
| |
| 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 |
| |
| // This function is a leaf since if the source and destination are both in native memory |
| // the copy may potentially be very large, and we don't want to disable GC if we can avoid it. |
| // If either source or destination (or both) are on the heap, the function will enter VM using |
| // JVM_ENTRY_FROM_LEAF |
| UNSAFE_LEAF(void, Unsafe_CopySwapMemory0(JNIEnv *env, jobject unsafe, jobject srcObj, jlong srcOffset, jobject dstObj, jlong dstOffset, jlong size, jlong elemSize)) { |
| size_t sz = (size_t)size; |
| size_t esz = (size_t)elemSize; |
| |
| if (srcObj == NULL && dstObj == NULL) { |
| // Both src & dst are in native memory |
| address src = (address)srcOffset; |
| address dst = (address)dstOffset; |
| |
| Copy::conjoint_swap(src, dst, sz, esz); |
| } else { |
| // At least one of src/dst are on heap, transition to VM to access raw pointers |
| |
| JVM_ENTRY_FROM_LEAF(env, void, Unsafe_CopySwapMemory0) { |
| oop srcp = JNIHandles::resolve(srcObj); |
| oop dstp = JNIHandles::resolve(dstObj); |
| |
| address src = (address)index_oop_from_field_offset_long(srcp, srcOffset); |
| address dst = (address)index_oop_from_field_offset_long(dstp, dstOffset); |
| |
| Copy::conjoint_swap(src, dst, sz, esz); |
| } JVM_END |
| } |
| } UNSAFE_END |
| |
| ////// Random queries |
| |
| UNSAFE_LEAF(jint, Unsafe_AddressSize0(JNIEnv *env, jobject unsafe)) { |
| return sizeof(void*); |
| } UNSAFE_END |
| |
| UNSAFE_LEAF(jint, Unsafe_PageSize()) { |
| return os::vm_page_size(); |
| } UNSAFE_END |
| |
| static jint find_field_offset(jobject field, int must_be_static, TRAPS) { |
| assert(field != NULL, "field must not be NULL"); |
| |
| 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_ObjectFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) { |
| return find_field_offset(field, 0, THREAD); |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(jlong, Unsafe_StaticFieldOffset0(JNIEnv *env, jobject unsafe, jobject field)) { |
| return find_field_offset(field, 1, THREAD); |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(jobject, Unsafe_StaticFieldBase0(JNIEnv *env, jobject unsafe, jobject field)) { |
| assert(field != NULL, "field must not be NULL"); |
| |
| // 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. |
| |
| 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 |
| |
| UNSAFE_ENTRY(void, Unsafe_EnsureClassInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) { |
| assert(clazz != NULL, "clazz must not be NULL"); |
| |
| 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_ShouldBeInitialized0(JNIEnv *env, jobject unsafe, jobject clazz)) { |
| assert(clazz != NULL, "clazz must not be NULL"); |
| |
| 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 clazz, TRAPS) { |
| assert(clazz != NULL, "clazz must not be NULL"); |
| |
| oop mirror = JNIHandles::resolve_non_null(clazz); |
| Klass* k = java_lang_Class::as_Klass(mirror); |
| |
| if (k == NULL || !k->is_array_klass()) { |
| THROW(vmSymbols::java_lang_InvalidClassException()); |
| } else if (k->is_objArray_klass()) { |
| base = arrayOopDesc::base_offset_in_bytes(T_OBJECT); |
| scale = heapOopSize; |
| } else if (k->is_typeArray_klass()) { |
| 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_ArrayBaseOffset0(JNIEnv *env, jobject unsafe, jclass clazz)) { |
| int base = 0, scale = 0; |
| getBaseAndScale(base, scale, clazz, CHECK_0); |
| |
| return field_offset_from_byte_offset(base); |
| } UNSAFE_END |
| |
| |
| UNSAFE_ENTRY(jint, Unsafe_ArrayIndexScale0(JNIEnv *env, jobject unsafe, jclass clazz)) { |
| int base = 0, scale = 0; |
| getBaseAndScale(base, scale, clazz, 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]; |
| |
| jio_snprintf(buf, 100, "%s%s", "java/lang/", ename); |
| |
| jclass cls = env->FindClass(buf); |
| if (env->ExceptionCheck()) { |
| env->ExceptionClear(); |
| tty->print_cr("Unsafe: cannot throw %s because FindClass has failed", buf); |
| return; |
| } |
| |
| env->ThrowNew(cls, NULL); |
| } |
| |
| 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 = NULL; |
| jclass result = 0; |
| char buf[128]; |
| |
| assert(data != NULL, "Class bytes must not be NULL"); |
| assert(length >= 0, "length must not be negative: %d", length); |
| |
| if (UsePerfData) { |
| ClassLoader::unsafe_defineClassCallCounter()->inc(); |
| } |
| |
| body = NEW_C_HEAP_ARRAY(jbyte, length, mtInternal); |
| if (body == NULL) { |
| 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); |
| |
| for (uint i = 0; i < len; i++) { |
| if (utfName[i] == '.') utfName[i] = '/'; |
| } |
| } |
| |
| result = JVM_DefineClass(env, utfName, loader, body, length, pd); |
| |
| if (utfName && utfName != buf) { |
| FREE_C_HEAP_ARRAY(char, utfName); |
| } |
| |
| free_body: |
| FREE_C_HEAP_ARRAY(jbyte, body); |
| return result; |
| } |
| |
| |
| UNSAFE_ENTRY(jclass, Unsafe_DefineClass0(JNIEnv *env, jobject unsafe, jstring name, jbyteArray data, int offset, int length, jobject loader, jobject pd)) { |
| ThreadToNativeFromVM ttnfv(thread); |
| |
| return Unsafe_DefineClass_impl(env, name, data, offset, length, loader, pd); |
| } UNSAFE_END |
| |
| |
| // 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, |
| u1** temp_alloc, |
| TRAPS) { |
| assert(host_class != NULL, "host_class must not be NULL"); |
| assert(data != NULL, "data must not be NULL"); |
| |
| if (UsePerfData) { |
| ClassLoader::unsafe_defineClassCallCounter()->inc(); |
| } |
| |
| jint length = typeArrayOop(JNIHandles::resolve_non_null(data))->length(); |
| assert(length >= 0, "class_bytes_length must not be negative: %d", length); |
| |
| int class_bytes_length = (int) length; |
| |
| u1* class_bytes = NEW_C_HEAP_ARRAY(u1, length, mtInternal); |
| if (class_bytes == NULL) { |
| THROW_0(vmSymbols::java_lang_OutOfMemoryError()); |
| } |
| |
| // caller responsible to free it: |
| *temp_alloc = class_bytes; |
| |
| jbyte* array_base = typeArrayOop(JNIHandles::resolve_non_null(data))->byte_at_addr(0); |
| Copy::conjoint_jbytes(array_base, class_bytes, length); |
| |
| objArrayHandle cp_patches_h; |
| if (cp_patches_jh != NULL) { |
| oop p = JNIHandles::resolve_non_null(cp_patches_jh); |
| assert(p->is_objArray(), "cp_patches must be an object[]"); |
| cp_patches_h = objArrayHandle(THREAD, (objArrayOop)p); |
| } |
| |
| const Klass* host_klass = java_lang_Class::as_Klass(JNIHandles::resolve_non_null(host_class)); |
| assert(host_klass != NULL, "invariant"); |
| |
| 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, host_source, ClassFileStream::verify); |
| |
| 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; |
| } |
| |
| return instanceKlassHandle(THREAD, anonk); |
| } |
| |
| UNSAFE_ENTRY(jclass, Unsafe_DefineAnonymousClass0(JNIEnv *env, jobject unsafe, jclass host_class, jbyteArray data, jobjectArray cp_patches_jh)) { |
| ResourceMark rm(THREAD); |
| |
| instanceKlassHandle anon_klass; |
| jobject res_jh = NULL; |
| u1* 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(u1, temp_alloc); |
| } |
| |
| // 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_ThrowException(JNIEnv *env, jobject unsafe, jthrowable thr)) { |
| ThreadToNativeFromVM ttnfv(thread); |
| env->Throw(thr); |
| } UNSAFE_END |
| |
| // JSR166 ------------------------------------------------------------------ |
| |
| UNSAFE_ENTRY(jobject, Unsafe_CompareAndExchangeObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) { |
| 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); |
| if (res == e) { |
| update_barrier_set((void*)addr, x); |
| } |
| return JNIHandles::make_local(env, res); |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(jint, Unsafe_CompareAndExchangeInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) { |
| oop p = JNIHandles::resolve(obj); |
| jint* addr = (jint *) index_oop_from_field_offset_long(p, offset); |
| |
| return (jint)(Atomic::cmpxchg(x, addr, e)); |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(jlong, Unsafe_CompareAndExchangeLong(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jlong e, jlong x)) { |
| Handle p (THREAD, JNIHandles::resolve(obj)); |
| jlong* addr = (jlong*)(index_oop_from_field_offset_long(p(), offset)); |
| |
| #ifdef SUPPORTS_NATIVE_CX8 |
| return (jlong)(Atomic::cmpxchg(x, addr, e)); |
| #else |
| if (VM_Version::supports_cx8()) { |
| return (jlong)(Atomic::cmpxchg(x, addr, e)); |
| } else { |
| MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag); |
| |
| jlong val = Atomic::load(addr); |
| if (val == e) { |
| Atomic::store(x, addr); |
| } |
| return val; |
| } |
| #endif |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapObject(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jobject e_h, jobject x_h)) { |
| 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); |
| if (res != e) { |
| return false; |
| } |
| |
| update_barrier_set((void*)addr, x); |
| |
| return true; |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(jboolean, Unsafe_CompareAndSwapInt(JNIEnv *env, jobject unsafe, jobject obj, jlong offset, jint e, jint x)) { |
| 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)) { |
| Handle p(THREAD, JNIHandles::resolve(obj)); |
| jlong* addr = (jlong*)index_oop_from_field_offset_long(p(), offset); |
| |
| #ifdef SUPPORTS_NATIVE_CX8 |
| return (jlong)(Atomic::cmpxchg(x, addr, e)) == e; |
| #else |
| if (VM_Version::supports_cx8()) { |
| return (jlong)(Atomic::cmpxchg(x, addr, e)) == e; |
| } else { |
| MutexLockerEx mu(UnsafeJlong_lock, Mutex::_no_safepoint_check_flag); |
| |
| jlong val = Atomic::load(addr); |
| if (val != e) { |
| return false; |
| } |
| |
| Atomic::store(x, addr); |
| return true; |
| } |
| #endif |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(void, Unsafe_Park(JNIEnv *env, jobject unsafe, jboolean isAbsolute, jlong time)) { |
| EventThreadPark event; |
| HOTSPOT_THREAD_PARK_BEGIN((uintptr_t) thread->parker(), (int) isAbsolute, time); |
| |
| JavaThreadParkedState jtps(thread, time != 0); |
| thread->parker()->park(isAbsolute != 0, time); |
| |
| HOTSPOT_THREAD_PARK_END((uintptr_t) thread->parker()); |
| |
| 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)) { |
| 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) { |
| HOTSPOT_THREAD_UNPARK((uintptr_t) p); |
| p->unpark(); |
| } |
| } UNSAFE_END |
| |
| UNSAFE_ENTRY(jint, Unsafe_GetLoadAverage0(JNIEnv *env, jobject unsafe, jdoubleArray loadavg, jint nelem)) { |
| 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"); |
| |
| 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 |
| |
| |
| /// JVM_RegisterUnsafeMethods |
| |
| #define ADR "J" |
| |
| #define LANG "Ljava/lang/" |
| |
| #define OBJ LANG "Object;" |
| #define CLS LANG "Class;" |
| #define FLD LANG "reflect/Field;" |
| #define THR LANG "Throwable;" |
| |
| #define DC_Args LANG "String;[BII" LANG "ClassLoader;" "Ljava/security/ProtectionDomain;" |
| #define DAC_Args CLS "[B[" OBJ |
| |
| #define CC (char*) /*cast a literal from (const char*)*/ |
| #define FN_PTR(f) CAST_FROM_FN_PTR(void*, &f) |
| |
| #define DECLARE_GETPUTOOP(Type, Desc) \ |
| {CC "get" #Type, CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type)}, \ |
| {CC "put" #Type, CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Set##Type)}, \ |
| {CC "get" #Type "Volatile", CC "(" OBJ "J)" #Desc, FN_PTR(Unsafe_Get##Type##Volatile)}, \ |
| {CC "put" #Type "Volatile", CC "(" OBJ "J" #Desc ")V", FN_PTR(Unsafe_Set##Type##Volatile)} |
| |
| |
| #define DECLARE_GETPUTNATIVE(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)} |
| |
| static JNINativeMethod jdk_internal_misc_Unsafe_methods[] = { |
| {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)}, |
| |
| {CC "getUncompressedObject", CC "(" ADR ")" OBJ, FN_PTR(Unsafe_GetUncompressedObject)}, |
| {CC "getJavaMirror", CC "(" ADR ")" CLS, FN_PTR(Unsafe_GetJavaMirror)}, |
| {CC "getKlassPointer", CC "(" OBJ ")" ADR, FN_PTR(Unsafe_GetKlassPointer)}, |
| |
| DECLARE_GETPUTOOP(Boolean, Z), |
| DECLARE_GETPUTOOP(Byte, B), |
| DECLARE_GETPUTOOP(Short, S), |
| DECLARE_GETPUTOOP(Char, C), |
| DECLARE_GETPUTOOP(Int, I), |
| DECLARE_GETPUTOOP(Long, J), |
| DECLARE_GETPUTOOP(Float, F), |
| DECLARE_GETPUTOOP(Double, D), |
| |
| DECLARE_GETPUTNATIVE(Byte, B), |
| DECLARE_GETPUTNATIVE(Short, S), |
| DECLARE_GETPUTNATIVE(Char, C), |
| DECLARE_GETPUTNATIVE(Int, I), |
| DECLARE_GETPUTNATIVE(Long, J), |
| DECLARE_GETPUTNATIVE(Float, F), |
| DECLARE_GETPUTNATIVE(Double, D), |
| |
| {CC "getAddress", CC "(" ADR ")" ADR, FN_PTR(Unsafe_GetNativeAddress)}, |
| {CC "putAddress", CC "(" ADR "" ADR ")V", FN_PTR(Unsafe_SetNativeAddress)}, |
| |
| {CC "allocateMemory0", CC "(J)" ADR, FN_PTR(Unsafe_AllocateMemory0)}, |
| {CC "reallocateMemory0", CC "(" ADR "J)" ADR, FN_PTR(Unsafe_ReallocateMemory0)}, |
| {CC "freeMemory0", CC "(" ADR ")V", FN_PTR(Unsafe_FreeMemory0)}, |
| |
| {CC "objectFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_ObjectFieldOffset0)}, |
| {CC "staticFieldOffset0", CC "(" FLD ")J", FN_PTR(Unsafe_StaticFieldOffset0)}, |
| {CC "staticFieldBase0", CC "(" FLD ")" OBJ, FN_PTR(Unsafe_StaticFieldBase0)}, |
| {CC "ensureClassInitialized0", CC "(" CLS ")V", FN_PTR(Unsafe_EnsureClassInitialized0)}, |
| {CC "arrayBaseOffset0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayBaseOffset0)}, |
| {CC "arrayIndexScale0", CC "(" CLS ")I", FN_PTR(Unsafe_ArrayIndexScale0)}, |
| {CC "addressSize0", CC "()I", FN_PTR(Unsafe_AddressSize0)}, |
| {CC "pageSize", CC "()I", FN_PTR(Unsafe_PageSize)}, |
| |
| {CC "defineClass0", CC "(" DC_Args ")" CLS, FN_PTR(Unsafe_DefineClass0)}, |
| {CC "allocateInstance", CC "(" CLS ")" OBJ, FN_PTR(Unsafe_AllocateInstance)}, |
| {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 "compareAndExchangeObjectVolatile", CC "(" OBJ "J" OBJ "" OBJ ")" OBJ, FN_PTR(Unsafe_CompareAndExchangeObject)}, |
| {CC "compareAndExchangeIntVolatile", CC "(" OBJ "J""I""I"")I", FN_PTR(Unsafe_CompareAndExchangeInt)}, |
| {CC "compareAndExchangeLongVolatile", CC "(" OBJ "J""J""J"")J", FN_PTR(Unsafe_CompareAndExchangeLong)}, |
| |
| {CC "park", CC "(ZJ)V", FN_PTR(Unsafe_Park)}, |
| {CC "unpark", CC "(" OBJ ")V", FN_PTR(Unsafe_Unpark)}, |
| |
| {CC "getLoadAverage0", CC "([DI)I", FN_PTR(Unsafe_GetLoadAverage0)}, |
| |
| {CC "copyMemory0", CC "(" OBJ "J" OBJ "JJ)V", FN_PTR(Unsafe_CopyMemory0)}, |
| {CC "copySwapMemory0", CC "(" OBJ "J" OBJ "JJJ)V", FN_PTR(Unsafe_CopySwapMemory0)}, |
| {CC "setMemory0", CC "(" OBJ "JJB)V", FN_PTR(Unsafe_SetMemory0)}, |
| |
| {CC "defineAnonymousClass0", CC "(" DAC_Args ")" CLS, FN_PTR(Unsafe_DefineAnonymousClass0)}, |
| |
| {CC "shouldBeInitialized0", CC "(" CLS ")Z", FN_PTR(Unsafe_ShouldBeInitialized0)}, |
| |
| {CC "loadFence", CC "()V", FN_PTR(Unsafe_LoadFence)}, |
| {CC "storeFence", CC "()V", FN_PTR(Unsafe_StoreFence)}, |
| {CC "fullFence", CC "()V", FN_PTR(Unsafe_FullFence)}, |
| |
| {CC "isBigEndian0", CC "()Z", FN_PTR(Unsafe_isBigEndian0)}, |
| {CC "unalignedAccess0", CC "()Z", FN_PTR(Unsafe_unalignedAccess0)} |
| }; |
| |
| #undef CC |
| #undef FN_PTR |
| |
| #undef ADR |
| #undef LANG |
| #undef OBJ |
| #undef CLS |
| #undef FLD |
| #undef THR |
| #undef DC_Args |
| #undef DAC_Args |
| |
| #undef DECLARE_GETPUTOOP |
| #undef DECLARE_GETPUTNATIVE |
| |
| |
| // This 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_RegisterJDKInternalMiscUnsafeMethods(JNIEnv *env, jclass unsafeclass)) { |
| ThreadToNativeFromVM ttnfv(thread); |
| |
| int ok = env->RegisterNatives(unsafeclass, jdk_internal_misc_Unsafe_methods, sizeof(jdk_internal_misc_Unsafe_methods)/sizeof(JNINativeMethod)); |
| guarantee(ok == 0, "register jdk.internal.misc.Unsafe natives"); |
| } JVM_END |