| /* |
| * Copyright (c) 2008, 2018, 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. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * 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. |
| */ |
| |
| package java.lang.invoke; |
| |
| import jdk.internal.misc.Unsafe; |
| import jdk.internal.vm.annotation.ForceInline; |
| import jdk.internal.vm.annotation.Stable; |
| import sun.invoke.util.ValueConversions; |
| import sun.invoke.util.VerifyAccess; |
| import sun.invoke.util.VerifyType; |
| import sun.invoke.util.Wrapper; |
| |
| import java.lang.ref.WeakReference; |
| import java.util.Arrays; |
| import java.util.Objects; |
| |
| import static java.lang.invoke.LambdaForm.*; |
| import static java.lang.invoke.LambdaForm.Kind.*; |
| import static java.lang.invoke.MethodHandleNatives.Constants.*; |
| import static java.lang.invoke.MethodHandleStatics.UNSAFE; |
| import static java.lang.invoke.MethodHandleStatics.newInternalError; |
| import static java.lang.invoke.MethodTypeForm.*; |
| |
| /** |
| * The flavor of method handle which implements a constant reference |
| * to a class member. |
| * @author jrose |
| */ |
| class DirectMethodHandle extends MethodHandle { |
| final MemberName member; |
| |
| // Constructors and factory methods in this class *must* be package scoped or private. |
| private DirectMethodHandle(MethodType mtype, LambdaForm form, MemberName member) { |
| super(mtype, form); |
| if (!member.isResolved()) throw new InternalError(); |
| |
| if (member.getDeclaringClass().isInterface() && |
| member.getReferenceKind() == REF_invokeInterface && |
| member.isMethod() && !member.isAbstract()) { |
| // Check for corner case: invokeinterface of Object method |
| MemberName m = new MemberName(Object.class, member.getName(), member.getMethodType(), member.getReferenceKind()); |
| m = MemberName.getFactory().resolveOrNull(m.getReferenceKind(), m, null); |
| if (m != null && m.isPublic()) { |
| assert(member.getReferenceKind() == m.getReferenceKind()); // else this.form is wrong |
| member = m; |
| } |
| } |
| |
| this.member = member; |
| } |
| |
| // Factory methods: |
| static DirectMethodHandle make(byte refKind, Class<?> refc, MemberName member, Class<?> callerClass) { |
| MethodType mtype = member.getMethodOrFieldType(); |
| if (!member.isStatic()) { |
| if (!member.getDeclaringClass().isAssignableFrom(refc) || member.isConstructor()) |
| throw new InternalError(member.toString()); |
| mtype = mtype.insertParameterTypes(0, refc); |
| } |
| if (!member.isField()) { |
| // refKind reflects the original type of lookup via findSpecial or |
| // findVirtual etc. |
| switch (refKind) { |
| case REF_invokeSpecial: { |
| member = member.asSpecial(); |
| // if caller is an interface we need to adapt to get the |
| // receiver check inserted |
| if (callerClass == null) { |
| throw new InternalError("callerClass must not be null for REF_invokeSpecial"); |
| } |
| LambdaForm lform = preparedLambdaForm(member, callerClass.isInterface()); |
| return new Special(mtype, lform, member, callerClass); |
| } |
| case REF_invokeInterface: { |
| // for interfaces we always need the receiver typecheck, |
| // so we always pass 'true' to ensure we adapt if needed |
| // to include the REF_invokeSpecial case |
| LambdaForm lform = preparedLambdaForm(member, true); |
| return new Interface(mtype, lform, member, refc); |
| } |
| default: { |
| LambdaForm lform = preparedLambdaForm(member); |
| return new DirectMethodHandle(mtype, lform, member); |
| } |
| } |
| } else { |
| LambdaForm lform = preparedFieldLambdaForm(member); |
| if (member.isStatic()) { |
| long offset = MethodHandleNatives.staticFieldOffset(member); |
| Object base = MethodHandleNatives.staticFieldBase(member); |
| return new StaticAccessor(mtype, lform, member, base, offset); |
| } else { |
| long offset = MethodHandleNatives.objectFieldOffset(member); |
| assert(offset == (int)offset); |
| return new Accessor(mtype, lform, member, (int)offset); |
| } |
| } |
| } |
| static DirectMethodHandle make(Class<?> refc, MemberName member) { |
| byte refKind = member.getReferenceKind(); |
| if (refKind == REF_invokeSpecial) |
| refKind = REF_invokeVirtual; |
| return make(refKind, refc, member, null /* no callerClass context */); |
| } |
| static DirectMethodHandle make(MemberName member) { |
| if (member.isConstructor()) |
| return makeAllocator(member); |
| return make(member.getDeclaringClass(), member); |
| } |
| private static DirectMethodHandle makeAllocator(MemberName ctor) { |
| assert(ctor.isConstructor() && ctor.getName().equals("<init>")); |
| Class<?> instanceClass = ctor.getDeclaringClass(); |
| ctor = ctor.asConstructor(); |
| assert(ctor.isConstructor() && ctor.getReferenceKind() == REF_newInvokeSpecial) : ctor; |
| MethodType mtype = ctor.getMethodType().changeReturnType(instanceClass); |
| LambdaForm lform = preparedLambdaForm(ctor); |
| MemberName init = ctor.asSpecial(); |
| assert(init.getMethodType().returnType() == void.class); |
| return new Constructor(mtype, lform, ctor, init, instanceClass); |
| } |
| |
| @Override |
| BoundMethodHandle rebind() { |
| return BoundMethodHandle.makeReinvoker(this); |
| } |
| |
| @Override |
| MethodHandle copyWith(MethodType mt, LambdaForm lf) { |
| assert(this.getClass() == DirectMethodHandle.class); // must override in subclasses |
| return new DirectMethodHandle(mt, lf, member); |
| } |
| |
| @Override |
| String internalProperties() { |
| return "\n& DMH.MN="+internalMemberName(); |
| } |
| |
| //// Implementation methods. |
| @Override |
| @ForceInline |
| MemberName internalMemberName() { |
| return member; |
| } |
| |
| private static final MemberName.Factory IMPL_NAMES = MemberName.getFactory(); |
| |
| /** |
| * Create a LF which can invoke the given method. |
| * Cache and share this structure among all methods with |
| * the same basicType and refKind. |
| */ |
| private static LambdaForm preparedLambdaForm(MemberName m, boolean adaptToSpecialIfc) { |
| assert(m.isInvocable()) : m; // call preparedFieldLambdaForm instead |
| MethodType mtype = m.getInvocationType().basicType(); |
| assert(!m.isMethodHandleInvoke()) : m; |
| int which; |
| // MemberName.getReferenceKind represents the JVM optimized form of the call |
| // as distinct from the "kind" passed to DMH.make which represents the original |
| // bytecode-equivalent request. Specifically private/final methods that use a direct |
| // call have getReferenceKind adapted to REF_invokeSpecial, even though the actual |
| // invocation mode may be invokevirtual or invokeinterface. |
| switch (m.getReferenceKind()) { |
| case REF_invokeVirtual: which = LF_INVVIRTUAL; break; |
| case REF_invokeStatic: which = LF_INVSTATIC; break; |
| case REF_invokeSpecial: which = LF_INVSPECIAL; break; |
| case REF_invokeInterface: which = LF_INVINTERFACE; break; |
| case REF_newInvokeSpecial: which = LF_NEWINVSPECIAL; break; |
| default: throw new InternalError(m.toString()); |
| } |
| if (which == LF_INVSTATIC && shouldBeInitialized(m)) { |
| // precompute the barrier-free version: |
| preparedLambdaForm(mtype, which); |
| which = LF_INVSTATIC_INIT; |
| } |
| if (which == LF_INVSPECIAL && adaptToSpecialIfc) { |
| which = LF_INVSPECIAL_IFC; |
| } |
| LambdaForm lform = preparedLambdaForm(mtype, which); |
| maybeCompile(lform, m); |
| assert(lform.methodType().dropParameterTypes(0, 1) |
| .equals(m.getInvocationType().basicType())) |
| : Arrays.asList(m, m.getInvocationType().basicType(), lform, lform.methodType()); |
| return lform; |
| } |
| |
| private static LambdaForm preparedLambdaForm(MemberName m) { |
| return preparedLambdaForm(m, false); |
| } |
| |
| private static LambdaForm preparedLambdaForm(MethodType mtype, int which) { |
| LambdaForm lform = mtype.form().cachedLambdaForm(which); |
| if (lform != null) return lform; |
| lform = makePreparedLambdaForm(mtype, which); |
| return mtype.form().setCachedLambdaForm(which, lform); |
| } |
| |
| static LambdaForm makePreparedLambdaForm(MethodType mtype, int which) { |
| boolean needsInit = (which == LF_INVSTATIC_INIT); |
| boolean doesAlloc = (which == LF_NEWINVSPECIAL); |
| boolean needsReceiverCheck = (which == LF_INVINTERFACE || |
| which == LF_INVSPECIAL_IFC); |
| |
| String linkerName; |
| LambdaForm.Kind kind; |
| switch (which) { |
| case LF_INVVIRTUAL: linkerName = "linkToVirtual"; kind = DIRECT_INVOKE_VIRTUAL; break; |
| case LF_INVSTATIC: linkerName = "linkToStatic"; kind = DIRECT_INVOKE_STATIC; break; |
| case LF_INVSTATIC_INIT:linkerName = "linkToStatic"; kind = DIRECT_INVOKE_STATIC_INIT; break; |
| case LF_INVSPECIAL_IFC:linkerName = "linkToSpecial"; kind = DIRECT_INVOKE_SPECIAL_IFC; break; |
| case LF_INVSPECIAL: linkerName = "linkToSpecial"; kind = DIRECT_INVOKE_SPECIAL; break; |
| case LF_INVINTERFACE: linkerName = "linkToInterface"; kind = DIRECT_INVOKE_INTERFACE; break; |
| case LF_NEWINVSPECIAL: linkerName = "linkToSpecial"; kind = DIRECT_NEW_INVOKE_SPECIAL; break; |
| default: throw new InternalError("which="+which); |
| } |
| |
| MethodType mtypeWithArg = mtype.appendParameterTypes(MemberName.class); |
| if (doesAlloc) |
| mtypeWithArg = mtypeWithArg |
| .insertParameterTypes(0, Object.class) // insert newly allocated obj |
| .changeReturnType(void.class); // <init> returns void |
| MemberName linker = new MemberName(MethodHandle.class, linkerName, mtypeWithArg, REF_invokeStatic); |
| try { |
| linker = IMPL_NAMES.resolveOrFail(REF_invokeStatic, linker, null, NoSuchMethodException.class); |
| } catch (ReflectiveOperationException ex) { |
| throw newInternalError(ex); |
| } |
| final int DMH_THIS = 0; |
| final int ARG_BASE = 1; |
| final int ARG_LIMIT = ARG_BASE + mtype.parameterCount(); |
| int nameCursor = ARG_LIMIT; |
| final int NEW_OBJ = (doesAlloc ? nameCursor++ : -1); |
| final int GET_MEMBER = nameCursor++; |
| final int CHECK_RECEIVER = (needsReceiverCheck ? nameCursor++ : -1); |
| final int LINKER_CALL = nameCursor++; |
| Name[] names = arguments(nameCursor - ARG_LIMIT, mtype.invokerType()); |
| assert(names.length == nameCursor); |
| if (doesAlloc) { |
| // names = { argx,y,z,... new C, init method } |
| names[NEW_OBJ] = new Name(getFunction(NF_allocateInstance), names[DMH_THIS]); |
| names[GET_MEMBER] = new Name(getFunction(NF_constructorMethod), names[DMH_THIS]); |
| } else if (needsInit) { |
| names[GET_MEMBER] = new Name(getFunction(NF_internalMemberNameEnsureInit), names[DMH_THIS]); |
| } else { |
| names[GET_MEMBER] = new Name(getFunction(NF_internalMemberName), names[DMH_THIS]); |
| } |
| assert(findDirectMethodHandle(names[GET_MEMBER]) == names[DMH_THIS]); |
| Object[] outArgs = Arrays.copyOfRange(names, ARG_BASE, GET_MEMBER+1, Object[].class); |
| if (needsReceiverCheck) { |
| names[CHECK_RECEIVER] = new Name(getFunction(NF_checkReceiver), names[DMH_THIS], names[ARG_BASE]); |
| outArgs[0] = names[CHECK_RECEIVER]; |
| } |
| assert(outArgs[outArgs.length-1] == names[GET_MEMBER]); // look, shifted args! |
| int result = LAST_RESULT; |
| if (doesAlloc) { |
| assert(outArgs[outArgs.length-2] == names[NEW_OBJ]); // got to move this one |
| System.arraycopy(outArgs, 0, outArgs, 1, outArgs.length-2); |
| outArgs[0] = names[NEW_OBJ]; |
| result = NEW_OBJ; |
| } |
| names[LINKER_CALL] = new Name(linker, outArgs); |
| LambdaForm lform = new LambdaForm(ARG_LIMIT, names, result, kind); |
| |
| // This is a tricky bit of code. Don't send it through the LF interpreter. |
| lform.compileToBytecode(); |
| return lform; |
| } |
| |
| /* assert */ static Object findDirectMethodHandle(Name name) { |
| if (name.function.equals(getFunction(NF_internalMemberName)) || |
| name.function.equals(getFunction(NF_internalMemberNameEnsureInit)) || |
| name.function.equals(getFunction(NF_constructorMethod))) { |
| assert(name.arguments.length == 1); |
| return name.arguments[0]; |
| } |
| return null; |
| } |
| |
| private static void maybeCompile(LambdaForm lform, MemberName m) { |
| if (lform.vmentry == null && VerifyAccess.isSamePackage(m.getDeclaringClass(), MethodHandle.class)) |
| // Help along bootstrapping... |
| lform.compileToBytecode(); |
| } |
| |
| /** Static wrapper for DirectMethodHandle.internalMemberName. */ |
| @ForceInline |
| /*non-public*/ static Object internalMemberName(Object mh) { |
| return ((DirectMethodHandle)mh).member; |
| } |
| |
| /** Static wrapper for DirectMethodHandle.internalMemberName. |
| * This one also forces initialization. |
| */ |
| /*non-public*/ static Object internalMemberNameEnsureInit(Object mh) { |
| DirectMethodHandle dmh = (DirectMethodHandle)mh; |
| dmh.ensureInitialized(); |
| return dmh.member; |
| } |
| |
| /*non-public*/ static |
| boolean shouldBeInitialized(MemberName member) { |
| switch (member.getReferenceKind()) { |
| case REF_invokeStatic: |
| case REF_getStatic: |
| case REF_putStatic: |
| case REF_newInvokeSpecial: |
| break; |
| default: |
| // No need to initialize the class on this kind of member. |
| return false; |
| } |
| Class<?> cls = member.getDeclaringClass(); |
| if (cls == ValueConversions.class || |
| cls == MethodHandleImpl.class || |
| cls == Invokers.class) { |
| // These guys have lots of <clinit> DMH creation but we know |
| // the MHs will not be used until the system is booted. |
| return false; |
| } |
| if (VerifyAccess.isSamePackage(MethodHandle.class, cls) || |
| VerifyAccess.isSamePackage(ValueConversions.class, cls)) { |
| // It is a system class. It is probably in the process of |
| // being initialized, but we will help it along just to be safe. |
| if (UNSAFE.shouldBeInitialized(cls)) { |
| UNSAFE.ensureClassInitialized(cls); |
| } |
| return false; |
| } |
| return UNSAFE.shouldBeInitialized(cls); |
| } |
| |
| private static class EnsureInitialized extends ClassValue<WeakReference<Thread>> { |
| @Override |
| protected WeakReference<Thread> computeValue(Class<?> type) { |
| UNSAFE.ensureClassInitialized(type); |
| if (UNSAFE.shouldBeInitialized(type)) |
| // If the previous call didn't block, this can happen. |
| // We are executing inside <clinit>. |
| return new WeakReference<>(Thread.currentThread()); |
| return null; |
| } |
| static final EnsureInitialized INSTANCE = new EnsureInitialized(); |
| } |
| |
| private void ensureInitialized() { |
| if (checkInitialized(member)) { |
| // The coast is clear. Delete the <clinit> barrier. |
| if (member.isField()) |
| updateForm(preparedFieldLambdaForm(member)); |
| else |
| updateForm(preparedLambdaForm(member)); |
| } |
| } |
| private static boolean checkInitialized(MemberName member) { |
| Class<?> defc = member.getDeclaringClass(); |
| WeakReference<Thread> ref = EnsureInitialized.INSTANCE.get(defc); |
| if (ref == null) { |
| return true; // the final state |
| } |
| Thread clinitThread = ref.get(); |
| // Somebody may still be running defc.<clinit>. |
| if (clinitThread == Thread.currentThread()) { |
| // If anybody is running defc.<clinit>, it is this thread. |
| if (UNSAFE.shouldBeInitialized(defc)) |
| // Yes, we are running it; keep the barrier for now. |
| return false; |
| } else { |
| // We are in a random thread. Block. |
| UNSAFE.ensureClassInitialized(defc); |
| } |
| assert(!UNSAFE.shouldBeInitialized(defc)); |
| // put it into the final state |
| EnsureInitialized.INSTANCE.remove(defc); |
| return true; |
| } |
| |
| /*non-public*/ static void ensureInitialized(Object mh) { |
| ((DirectMethodHandle)mh).ensureInitialized(); |
| } |
| |
| /** This subclass represents invokespecial instructions. */ |
| static class Special extends DirectMethodHandle { |
| private final Class<?> caller; |
| private Special(MethodType mtype, LambdaForm form, MemberName member, Class<?> caller) { |
| super(mtype, form, member); |
| this.caller = caller; |
| } |
| @Override |
| boolean isInvokeSpecial() { |
| return true; |
| } |
| @Override |
| MethodHandle copyWith(MethodType mt, LambdaForm lf) { |
| return new Special(mt, lf, member, caller); |
| } |
| Object checkReceiver(Object recv) { |
| if (!caller.isInstance(recv)) { |
| String msg = String.format("Receiver class %s is not a subclass of caller class %s", |
| recv.getClass().getName(), caller.getName()); |
| throw new IncompatibleClassChangeError(msg); |
| } |
| return recv; |
| } |
| } |
| |
| /** This subclass represents invokeinterface instructions. */ |
| static class Interface extends DirectMethodHandle { |
| private final Class<?> refc; |
| private Interface(MethodType mtype, LambdaForm form, MemberName member, Class<?> refc) { |
| super(mtype, form, member); |
| assert refc.isInterface() : refc; |
| this.refc = refc; |
| } |
| @Override |
| MethodHandle copyWith(MethodType mt, LambdaForm lf) { |
| return new Interface(mt, lf, member, refc); |
| } |
| @Override |
| Object checkReceiver(Object recv) { |
| if (!refc.isInstance(recv)) { |
| String msg = String.format("Receiver class %s does not implement the requested interface %s", |
| recv.getClass().getName(), refc.getName()); |
| throw new IncompatibleClassChangeError(msg); |
| } |
| return recv; |
| } |
| } |
| |
| /** Used for interface receiver type checks, by Interface and Special modes. */ |
| Object checkReceiver(Object recv) { |
| throw new InternalError("Should only be invoked on a subclass"); |
| } |
| |
| |
| /** This subclass handles constructor references. */ |
| static class Constructor extends DirectMethodHandle { |
| final MemberName initMethod; |
| final Class<?> instanceClass; |
| |
| private Constructor(MethodType mtype, LambdaForm form, MemberName constructor, |
| MemberName initMethod, Class<?> instanceClass) { |
| super(mtype, form, constructor); |
| this.initMethod = initMethod; |
| this.instanceClass = instanceClass; |
| assert(initMethod.isResolved()); |
| } |
| @Override |
| MethodHandle copyWith(MethodType mt, LambdaForm lf) { |
| return new Constructor(mt, lf, member, initMethod, instanceClass); |
| } |
| } |
| |
| /*non-public*/ static Object constructorMethod(Object mh) { |
| Constructor dmh = (Constructor)mh; |
| return dmh.initMethod; |
| } |
| |
| /*non-public*/ static Object allocateInstance(Object mh) throws InstantiationException { |
| Constructor dmh = (Constructor)mh; |
| return UNSAFE.allocateInstance(dmh.instanceClass); |
| } |
| |
| /** This subclass handles non-static field references. */ |
| static class Accessor extends DirectMethodHandle { |
| final Class<?> fieldType; |
| final int fieldOffset; |
| private Accessor(MethodType mtype, LambdaForm form, MemberName member, |
| int fieldOffset) { |
| super(mtype, form, member); |
| this.fieldType = member.getFieldType(); |
| this.fieldOffset = fieldOffset; |
| } |
| |
| @Override Object checkCast(Object obj) { |
| return fieldType.cast(obj); |
| } |
| @Override |
| MethodHandle copyWith(MethodType mt, LambdaForm lf) { |
| return new Accessor(mt, lf, member, fieldOffset); |
| } |
| } |
| |
| @ForceInline |
| /*non-public*/ static long fieldOffset(Object accessorObj) { |
| // Note: We return a long because that is what Unsafe.getObject likes. |
| // We store a plain int because it is more compact. |
| return ((Accessor)accessorObj).fieldOffset; |
| } |
| |
| @ForceInline |
| /*non-public*/ static Object checkBase(Object obj) { |
| // Note that the object's class has already been verified, |
| // since the parameter type of the Accessor method handle |
| // is either member.getDeclaringClass or a subclass. |
| // This was verified in DirectMethodHandle.make. |
| // Therefore, the only remaining check is for null. |
| // Since this check is *not* guaranteed by Unsafe.getInt |
| // and its siblings, we need to make an explicit one here. |
| return Objects.requireNonNull(obj); |
| } |
| |
| /** This subclass handles static field references. */ |
| static class StaticAccessor extends DirectMethodHandle { |
| private final Class<?> fieldType; |
| private final Object staticBase; |
| private final long staticOffset; |
| |
| private StaticAccessor(MethodType mtype, LambdaForm form, MemberName member, |
| Object staticBase, long staticOffset) { |
| super(mtype, form, member); |
| this.fieldType = member.getFieldType(); |
| this.staticBase = staticBase; |
| this.staticOffset = staticOffset; |
| } |
| |
| @Override Object checkCast(Object obj) { |
| return fieldType.cast(obj); |
| } |
| @Override |
| MethodHandle copyWith(MethodType mt, LambdaForm lf) { |
| return new StaticAccessor(mt, lf, member, staticBase, staticOffset); |
| } |
| } |
| |
| @ForceInline |
| /*non-public*/ static Object nullCheck(Object obj) { |
| return Objects.requireNonNull(obj); |
| } |
| |
| @ForceInline |
| /*non-public*/ static Object staticBase(Object accessorObj) { |
| return ((StaticAccessor)accessorObj).staticBase; |
| } |
| |
| @ForceInline |
| /*non-public*/ static long staticOffset(Object accessorObj) { |
| return ((StaticAccessor)accessorObj).staticOffset; |
| } |
| |
| @ForceInline |
| /*non-public*/ static Object checkCast(Object mh, Object obj) { |
| return ((DirectMethodHandle) mh).checkCast(obj); |
| } |
| |
| Object checkCast(Object obj) { |
| return member.getReturnType().cast(obj); |
| } |
| |
| // Caching machinery for field accessors: |
| static final byte |
| AF_GETFIELD = 0, |
| AF_PUTFIELD = 1, |
| AF_GETSTATIC = 2, |
| AF_PUTSTATIC = 3, |
| AF_GETSTATIC_INIT = 4, |
| AF_PUTSTATIC_INIT = 5, |
| AF_LIMIT = 6; |
| // Enumerate the different field kinds using Wrapper, |
| // with an extra case added for checked references. |
| static final int |
| FT_LAST_WRAPPER = Wrapper.COUNT-1, |
| FT_UNCHECKED_REF = Wrapper.OBJECT.ordinal(), |
| FT_CHECKED_REF = FT_LAST_WRAPPER+1, |
| FT_LIMIT = FT_LAST_WRAPPER+2; |
| private static int afIndex(byte formOp, boolean isVolatile, int ftypeKind) { |
| return ((formOp * FT_LIMIT * 2) |
| + (isVolatile ? FT_LIMIT : 0) |
| + ftypeKind); |
| } |
| @Stable |
| private static final LambdaForm[] ACCESSOR_FORMS |
| = new LambdaForm[afIndex(AF_LIMIT, false, 0)]; |
| static int ftypeKind(Class<?> ftype) { |
| if (ftype.isPrimitive()) |
| return Wrapper.forPrimitiveType(ftype).ordinal(); |
| else if (VerifyType.isNullReferenceConversion(Object.class, ftype)) |
| return FT_UNCHECKED_REF; |
| else |
| return FT_CHECKED_REF; |
| } |
| |
| /** |
| * Create a LF which can access the given field. |
| * Cache and share this structure among all fields with |
| * the same basicType and refKind. |
| */ |
| private static LambdaForm preparedFieldLambdaForm(MemberName m) { |
| Class<?> ftype = m.getFieldType(); |
| boolean isVolatile = m.isVolatile(); |
| byte formOp; |
| switch (m.getReferenceKind()) { |
| case REF_getField: formOp = AF_GETFIELD; break; |
| case REF_putField: formOp = AF_PUTFIELD; break; |
| case REF_getStatic: formOp = AF_GETSTATIC; break; |
| case REF_putStatic: formOp = AF_PUTSTATIC; break; |
| default: throw new InternalError(m.toString()); |
| } |
| if (shouldBeInitialized(m)) { |
| // precompute the barrier-free version: |
| preparedFieldLambdaForm(formOp, isVolatile, ftype); |
| assert((AF_GETSTATIC_INIT - AF_GETSTATIC) == |
| (AF_PUTSTATIC_INIT - AF_PUTSTATIC)); |
| formOp += (AF_GETSTATIC_INIT - AF_GETSTATIC); |
| } |
| LambdaForm lform = preparedFieldLambdaForm(formOp, isVolatile, ftype); |
| maybeCompile(lform, m); |
| assert(lform.methodType().dropParameterTypes(0, 1) |
| .equals(m.getInvocationType().basicType())) |
| : Arrays.asList(m, m.getInvocationType().basicType(), lform, lform.methodType()); |
| return lform; |
| } |
| private static LambdaForm preparedFieldLambdaForm(byte formOp, boolean isVolatile, Class<?> ftype) { |
| int ftypeKind = ftypeKind(ftype); |
| int afIndex = afIndex(formOp, isVolatile, ftypeKind); |
| LambdaForm lform = ACCESSOR_FORMS[afIndex]; |
| if (lform != null) return lform; |
| lform = makePreparedFieldLambdaForm(formOp, isVolatile, ftypeKind); |
| ACCESSOR_FORMS[afIndex] = lform; // don't bother with a CAS |
| return lform; |
| } |
| |
| private static final Wrapper[] ALL_WRAPPERS = Wrapper.values(); |
| |
| private static Kind getFieldKind(boolean isGetter, boolean isVolatile, Wrapper wrapper) { |
| if (isGetter) { |
| if (isVolatile) { |
| switch (wrapper) { |
| case BOOLEAN: return GET_BOOLEAN_VOLATILE; |
| case BYTE: return GET_BYTE_VOLATILE; |
| case SHORT: return GET_SHORT_VOLATILE; |
| case CHAR: return GET_CHAR_VOLATILE; |
| case INT: return GET_INT_VOLATILE; |
| case LONG: return GET_LONG_VOLATILE; |
| case FLOAT: return GET_FLOAT_VOLATILE; |
| case DOUBLE: return GET_DOUBLE_VOLATILE; |
| case OBJECT: return GET_OBJECT_VOLATILE; |
| } |
| } else { |
| switch (wrapper) { |
| case BOOLEAN: return GET_BOOLEAN; |
| case BYTE: return GET_BYTE; |
| case SHORT: return GET_SHORT; |
| case CHAR: return GET_CHAR; |
| case INT: return GET_INT; |
| case LONG: return GET_LONG; |
| case FLOAT: return GET_FLOAT; |
| case DOUBLE: return GET_DOUBLE; |
| case OBJECT: return GET_OBJECT; |
| } |
| } |
| } else { |
| if (isVolatile) { |
| switch (wrapper) { |
| case BOOLEAN: return PUT_BOOLEAN_VOLATILE; |
| case BYTE: return PUT_BYTE_VOLATILE; |
| case SHORT: return PUT_SHORT_VOLATILE; |
| case CHAR: return PUT_CHAR_VOLATILE; |
| case INT: return PUT_INT_VOLATILE; |
| case LONG: return PUT_LONG_VOLATILE; |
| case FLOAT: return PUT_FLOAT_VOLATILE; |
| case DOUBLE: return PUT_DOUBLE_VOLATILE; |
| case OBJECT: return PUT_OBJECT_VOLATILE; |
| } |
| } else { |
| switch (wrapper) { |
| case BOOLEAN: return PUT_BOOLEAN; |
| case BYTE: return PUT_BYTE; |
| case SHORT: return PUT_SHORT; |
| case CHAR: return PUT_CHAR; |
| case INT: return PUT_INT; |
| case LONG: return PUT_LONG; |
| case FLOAT: return PUT_FLOAT; |
| case DOUBLE: return PUT_DOUBLE; |
| case OBJECT: return PUT_OBJECT; |
| } |
| } |
| } |
| throw new AssertionError("Invalid arguments"); |
| } |
| |
| static LambdaForm makePreparedFieldLambdaForm(byte formOp, boolean isVolatile, int ftypeKind) { |
| boolean isGetter = (formOp & 1) == (AF_GETFIELD & 1); |
| boolean isStatic = (formOp >= AF_GETSTATIC); |
| boolean needsInit = (formOp >= AF_GETSTATIC_INIT); |
| boolean needsCast = (ftypeKind == FT_CHECKED_REF); |
| Wrapper fw = (needsCast ? Wrapper.OBJECT : ALL_WRAPPERS[ftypeKind]); |
| Class<?> ft = fw.primitiveType(); |
| assert(ftypeKind(needsCast ? String.class : ft) == ftypeKind); |
| |
| // getObject, putIntVolatile, etc. |
| Kind kind = getFieldKind(isGetter, isVolatile, fw); |
| |
| MethodType linkerType; |
| if (isGetter) |
| linkerType = MethodType.methodType(ft, Object.class, long.class); |
| else |
| linkerType = MethodType.methodType(void.class, Object.class, long.class, ft); |
| MemberName linker = new MemberName(Unsafe.class, kind.methodName, linkerType, REF_invokeVirtual); |
| try { |
| linker = IMPL_NAMES.resolveOrFail(REF_invokeVirtual, linker, null, NoSuchMethodException.class); |
| } catch (ReflectiveOperationException ex) { |
| throw newInternalError(ex); |
| } |
| |
| // What is the external type of the lambda form? |
| MethodType mtype; |
| if (isGetter) |
| mtype = MethodType.methodType(ft); |
| else |
| mtype = MethodType.methodType(void.class, ft); |
| mtype = mtype.basicType(); // erase short to int, etc. |
| if (!isStatic) |
| mtype = mtype.insertParameterTypes(0, Object.class); |
| final int DMH_THIS = 0; |
| final int ARG_BASE = 1; |
| final int ARG_LIMIT = ARG_BASE + mtype.parameterCount(); |
| // if this is for non-static access, the base pointer is stored at this index: |
| final int OBJ_BASE = isStatic ? -1 : ARG_BASE; |
| // if this is for write access, the value to be written is stored at this index: |
| final int SET_VALUE = isGetter ? -1 : ARG_LIMIT - 1; |
| int nameCursor = ARG_LIMIT; |
| final int F_HOLDER = (isStatic ? nameCursor++ : -1); // static base if any |
| final int F_OFFSET = nameCursor++; // Either static offset or field offset. |
| final int OBJ_CHECK = (OBJ_BASE >= 0 ? nameCursor++ : -1); |
| final int U_HOLDER = nameCursor++; // UNSAFE holder |
| final int INIT_BAR = (needsInit ? nameCursor++ : -1); |
| final int PRE_CAST = (needsCast && !isGetter ? nameCursor++ : -1); |
| final int LINKER_CALL = nameCursor++; |
| final int POST_CAST = (needsCast && isGetter ? nameCursor++ : -1); |
| final int RESULT = nameCursor-1; // either the call or the cast |
| Name[] names = arguments(nameCursor - ARG_LIMIT, mtype.invokerType()); |
| if (needsInit) |
| names[INIT_BAR] = new Name(getFunction(NF_ensureInitialized), names[DMH_THIS]); |
| if (needsCast && !isGetter) |
| names[PRE_CAST] = new Name(getFunction(NF_checkCast), names[DMH_THIS], names[SET_VALUE]); |
| Object[] outArgs = new Object[1 + linkerType.parameterCount()]; |
| assert(outArgs.length == (isGetter ? 3 : 4)); |
| outArgs[0] = names[U_HOLDER] = new Name(getFunction(NF_UNSAFE)); |
| if (isStatic) { |
| outArgs[1] = names[F_HOLDER] = new Name(getFunction(NF_staticBase), names[DMH_THIS]); |
| outArgs[2] = names[F_OFFSET] = new Name(getFunction(NF_staticOffset), names[DMH_THIS]); |
| } else { |
| outArgs[1] = names[OBJ_CHECK] = new Name(getFunction(NF_checkBase), names[OBJ_BASE]); |
| outArgs[2] = names[F_OFFSET] = new Name(getFunction(NF_fieldOffset), names[DMH_THIS]); |
| } |
| if (!isGetter) { |
| outArgs[3] = (needsCast ? names[PRE_CAST] : names[SET_VALUE]); |
| } |
| for (Object a : outArgs) assert(a != null); |
| names[LINKER_CALL] = new Name(linker, outArgs); |
| if (needsCast && isGetter) |
| names[POST_CAST] = new Name(getFunction(NF_checkCast), names[DMH_THIS], names[LINKER_CALL]); |
| for (Name n : names) assert(n != null); |
| |
| LambdaForm form; |
| if (needsCast || needsInit) { |
| // can't use the pre-generated form when casting and/or initializing |
| form = new LambdaForm(ARG_LIMIT, names, RESULT); |
| } else { |
| form = new LambdaForm(ARG_LIMIT, names, RESULT, kind); |
| } |
| |
| if (LambdaForm.debugNames()) { |
| // add some detail to the lambdaForm debugname, |
| // significant only for debugging |
| StringBuilder nameBuilder = new StringBuilder(kind.methodName); |
| if (isStatic) { |
| nameBuilder.append("Static"); |
| } else { |
| nameBuilder.append("Field"); |
| } |
| if (needsCast) { |
| nameBuilder.append("Cast"); |
| } |
| if (needsInit) { |
| nameBuilder.append("Init"); |
| } |
| LambdaForm.associateWithDebugName(form, nameBuilder.toString()); |
| } |
| return form; |
| } |
| |
| /** |
| * Pre-initialized NamedFunctions for bootstrapping purposes. |
| */ |
| static final byte NF_internalMemberName = 0, |
| NF_internalMemberNameEnsureInit = 1, |
| NF_ensureInitialized = 2, |
| NF_fieldOffset = 3, |
| NF_checkBase = 4, |
| NF_staticBase = 5, |
| NF_staticOffset = 6, |
| NF_checkCast = 7, |
| NF_allocateInstance = 8, |
| NF_constructorMethod = 9, |
| NF_UNSAFE = 10, |
| NF_checkReceiver = 11, |
| NF_LIMIT = 12; |
| |
| private static final @Stable NamedFunction[] NFS = new NamedFunction[NF_LIMIT]; |
| |
| private static NamedFunction getFunction(byte func) { |
| NamedFunction nf = NFS[func]; |
| if (nf != null) { |
| return nf; |
| } |
| // Each nf must be statically invocable or we get tied up in our bootstraps. |
| nf = NFS[func] = createFunction(func); |
| assert(InvokerBytecodeGenerator.isStaticallyInvocable(nf)); |
| return nf; |
| } |
| |
| private static final MethodType OBJ_OBJ_TYPE = MethodType.methodType(Object.class, Object.class); |
| |
| private static final MethodType LONG_OBJ_TYPE = MethodType.methodType(long.class, Object.class); |
| |
| private static NamedFunction createFunction(byte func) { |
| try { |
| switch (func) { |
| case NF_internalMemberName: |
| return getNamedFunction("internalMemberName", OBJ_OBJ_TYPE); |
| case NF_internalMemberNameEnsureInit: |
| return getNamedFunction("internalMemberNameEnsureInit", OBJ_OBJ_TYPE); |
| case NF_ensureInitialized: |
| return getNamedFunction("ensureInitialized", MethodType.methodType(void.class, Object.class)); |
| case NF_fieldOffset: |
| return getNamedFunction("fieldOffset", LONG_OBJ_TYPE); |
| case NF_checkBase: |
| return getNamedFunction("checkBase", OBJ_OBJ_TYPE); |
| case NF_staticBase: |
| return getNamedFunction("staticBase", OBJ_OBJ_TYPE); |
| case NF_staticOffset: |
| return getNamedFunction("staticOffset", LONG_OBJ_TYPE); |
| case NF_checkCast: |
| return getNamedFunction("checkCast", MethodType.methodType(Object.class, Object.class, Object.class)); |
| case NF_allocateInstance: |
| return getNamedFunction("allocateInstance", OBJ_OBJ_TYPE); |
| case NF_constructorMethod: |
| return getNamedFunction("constructorMethod", OBJ_OBJ_TYPE); |
| case NF_UNSAFE: |
| MemberName member = new MemberName(MethodHandleStatics.class, "UNSAFE", Unsafe.class, REF_getField); |
| return new NamedFunction( |
| MemberName.getFactory() |
| .resolveOrFail(REF_getField, member, DirectMethodHandle.class, NoSuchMethodException.class)); |
| case NF_checkReceiver: |
| member = new MemberName(DirectMethodHandle.class, "checkReceiver", OBJ_OBJ_TYPE, REF_invokeVirtual); |
| return new NamedFunction( |
| MemberName.getFactory() |
| .resolveOrFail(REF_invokeVirtual, member, DirectMethodHandle.class, NoSuchMethodException.class)); |
| default: |
| throw newInternalError("Unknown function: " + func); |
| } |
| } catch (ReflectiveOperationException ex) { |
| throw newInternalError(ex); |
| } |
| } |
| |
| private static NamedFunction getNamedFunction(String name, MethodType type) |
| throws ReflectiveOperationException |
| { |
| MemberName member = new MemberName(DirectMethodHandle.class, name, type, REF_invokeStatic); |
| return new NamedFunction( |
| MemberName.getFactory() |
| .resolveOrFail(REF_invokeStatic, member, DirectMethodHandle.class, NoSuchMethodException.class)); |
| } |
| |
| static { |
| // The Holder class will contain pre-generated DirectMethodHandles resolved |
| // speculatively using MemberName.getFactory().resolveOrNull. However, that |
| // doesn't initialize the class, which subtly breaks inlining etc. By forcing |
| // initialization of the Holder class we avoid these issues. |
| UNSAFE.ensureClassInitialized(Holder.class); |
| } |
| |
| /* Placeholder class for DirectMethodHandles generated ahead of time */ |
| final class Holder {} |
| } |
