| /* |
| * Copyright (c) 2017, 2021, 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.access.SharedSecrets; |
| import jdk.internal.loader.BootLoader; |
| import jdk.internal.org.objectweb.asm.ClassWriter; |
| import jdk.internal.org.objectweb.asm.FieldVisitor; |
| import jdk.internal.org.objectweb.asm.MethodVisitor; |
| import jdk.internal.vm.annotation.Stable; |
| import sun.invoke.util.BytecodeName; |
| |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.Field; |
| import java.lang.reflect.Modifier; |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| import java.security.ProtectionDomain; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Objects; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.function.Function; |
| |
| import static java.lang.invoke.LambdaForm.*; |
| import static java.lang.invoke.MethodHandleNatives.Constants.REF_getStatic; |
| import static java.lang.invoke.MethodHandleNatives.Constants.REF_putStatic; |
| import static java.lang.invoke.MethodHandleStatics.*; |
| import static java.lang.invoke.MethodHandles.Lookup.IMPL_LOOKUP; |
| import static jdk.internal.org.objectweb.asm.Opcodes.*; |
| |
| /** |
| * Class specialization code. |
| * @param <T> top class under which species classes are created. |
| * @param <K> key which identifies individual specializations. |
| * @param <S> species data type. |
| */ |
| /*non-public*/ |
| abstract class ClassSpecializer<T,K,S extends ClassSpecializer<T,K,S>.SpeciesData> { |
| private final Class<T> topClass; |
| private final Class<K> keyType; |
| private final Class<S> metaType; |
| private final MemberName sdAccessor; |
| private final String sdFieldName; |
| private final List<MemberName> transformMethods; |
| private final MethodType baseConstructorType; |
| private final S topSpecies; |
| private final ConcurrentHashMap<K, Object> cache = new ConcurrentHashMap<>(); |
| private final Factory factory; |
| private @Stable boolean topClassIsSuper; |
| |
| /** Return the top type mirror, for type {@code T} */ |
| public final Class<T> topClass() { return topClass; } |
| |
| /** Return the key type mirror, for type {@code K} */ |
| public final Class<K> keyType() { return keyType; } |
| |
| /** Return the species metadata type mirror, for type {@code S} */ |
| public final Class<S> metaType() { return metaType; } |
| |
| /** Report the leading arguments (if any) required by every species factory. |
| * Every species factory adds its own field types as additional arguments, |
| * but these arguments always come first, in every factory method. |
| */ |
| protected MethodType baseConstructorType() { return baseConstructorType; } |
| |
| /** Return the trivial species for the null sequence of arguments. */ |
| protected final S topSpecies() { return topSpecies; } |
| |
| /** Return the list of transform methods originally given at creation of this specializer. */ |
| protected final List<MemberName> transformMethods() { return transformMethods; } |
| |
| /** Return the factory object used to build and load concrete species code. */ |
| protected final Factory factory() { return factory; } |
| |
| /** |
| * Constructor for this class specializer. |
| * @param topClass type mirror for T |
| * @param keyType type mirror for K |
| * @param metaType type mirror for S |
| * @param baseConstructorType principal constructor type |
| * @param sdAccessor the method used to get the speciesData |
| * @param sdFieldName the name of the species data field, inject the speciesData object |
| * @param transformMethods optional list of transformMethods |
| */ |
| protected ClassSpecializer(Class<T> topClass, |
| Class<K> keyType, |
| Class<S> metaType, |
| MethodType baseConstructorType, |
| MemberName sdAccessor, |
| String sdFieldName, |
| List<MemberName> transformMethods) { |
| this.topClass = topClass; |
| this.keyType = keyType; |
| this.metaType = metaType; |
| this.sdAccessor = sdAccessor; |
| this.transformMethods = List.copyOf(transformMethods); |
| this.sdFieldName = sdFieldName; |
| this.baseConstructorType = baseConstructorType.changeReturnType(void.class); |
| this.factory = makeFactory(); |
| K tsk = topSpeciesKey(); |
| S topSpecies = null; |
| if (tsk != null && topSpecies == null) { |
| // if there is a key, build the top species if needed: |
| topSpecies = findSpecies(tsk); |
| } |
| this.topSpecies = topSpecies; |
| } |
| |
| // Utilities for subclass constructors: |
| protected static <T> Constructor<T> reflectConstructor(Class<T> defc, Class<?>... ptypes) { |
| try { |
| return defc.getDeclaredConstructor(ptypes); |
| } catch (NoSuchMethodException ex) { |
| throw newIAE(defc.getName()+"("+MethodType.methodType(void.class, ptypes)+")", ex); |
| } |
| } |
| |
| protected static Field reflectField(Class<?> defc, String name) { |
| try { |
| return defc.getDeclaredField(name); |
| } catch (NoSuchFieldException ex) { |
| throw newIAE(defc.getName()+"."+name, ex); |
| } |
| } |
| |
| private static RuntimeException newIAE(String message, Throwable cause) { |
| return new IllegalArgumentException(message, cause); |
| } |
| |
| private static final Function<Object, Object> CREATE_RESERVATION = new Function<>() { |
| @Override |
| public Object apply(Object key) { |
| return new Object(); |
| } |
| }; |
| |
| public final S findSpecies(K key) { |
| // Note: Species instantiation may throw VirtualMachineError because of |
| // code cache overflow. If this happens the species bytecode may be |
| // loaded but not linked to its species metadata (with MH's etc). |
| // That will cause a throw out of Factory.loadSpecies. |
| // |
| // In a later attempt to get the same species, the already-loaded |
| // class will be present in the system dictionary, causing an |
| // error when the species generator tries to reload it. |
| // We try to detect this case and link the pre-existing code. |
| // |
| // Although it would be better to start fresh by loading a new |
| // copy, we have to salvage the previously loaded but broken code. |
| // (As an alternative, we might spin a new class with a new name, |
| // or use the anonymous class mechanism.) |
| // |
| // In the end, as long as everybody goes through this findSpecies method, |
| // it will ensure only one SpeciesData will be set successfully on a |
| // concrete class if ever. |
| // The concrete class is published via SpeciesData instance |
| // returned here only after the class and species data are linked together. |
| Object speciesDataOrReservation = cache.computeIfAbsent(key, CREATE_RESERVATION); |
| // Separating the creation of a placeholder SpeciesData instance above |
| // from the loading and linking a real one below ensures we can never |
| // accidentally call computeIfAbsent recursively. |
| S speciesData; |
| if (speciesDataOrReservation.getClass() == Object.class) { |
| synchronized (speciesDataOrReservation) { |
| Object existingSpeciesData = cache.get(key); |
| if (existingSpeciesData == speciesDataOrReservation) { // won the race |
| // create a new SpeciesData... |
| speciesData = newSpeciesData(key); |
| // load and link it... |
| speciesData = factory.loadSpecies(speciesData); |
| if (!cache.replace(key, existingSpeciesData, speciesData)) { |
| throw newInternalError("Concurrent loadSpecies"); |
| } |
| } else { // lost the race; the retrieved existingSpeciesData is the final |
| speciesData = metaType.cast(existingSpeciesData); |
| } |
| } |
| } else { |
| speciesData = metaType.cast(speciesDataOrReservation); |
| } |
| assert(speciesData != null && speciesData.isResolved()); |
| return speciesData; |
| } |
| |
| /** |
| * Meta-data wrapper for concrete subtypes of the top class. |
| * Each concrete subtype corresponds to a given sequence of basic field types (LIJFD). |
| * The fields are immutable; their values are fully specified at object construction. |
| * Each species supplies an array of getter functions which may be used in lambda forms. |
| * A concrete value is always constructed from the full tuple of its field values, |
| * accompanied by the required constructor parameters. |
| * There *may* also be transforms which cloning a species instance and |
| * either replace a constructor parameter or add one or more new field values. |
| * The shortest possible species has zero fields. |
| * Subtypes are not interrelated among themselves by subtyping, even though |
| * it would appear that a shorter species could serve as a supertype of a |
| * longer one which extends it. |
| */ |
| public abstract class SpeciesData { |
| // Bootstrapping requires circular relations Class -> SpeciesData -> Class |
| // Therefore, we need non-final links in the chain. Use @Stable fields. |
| private final K key; |
| private final List<Class<?>> fieldTypes; |
| @Stable private Class<? extends T> speciesCode; |
| @Stable private List<MethodHandle> factories; |
| @Stable private List<MethodHandle> getters; |
| @Stable private List<LambdaForm.NamedFunction> nominalGetters; |
| @Stable private final MethodHandle[] transformHelpers = new MethodHandle[transformMethods.size()]; |
| |
| protected SpeciesData(K key) { |
| this.key = keyType.cast(Objects.requireNonNull(key)); |
| List<Class<?>> types = deriveFieldTypes(key); |
| this.fieldTypes = List.copyOf(types); |
| } |
| |
| public final K key() { |
| return key; |
| } |
| |
| protected final List<Class<?>> fieldTypes() { |
| return fieldTypes; |
| } |
| |
| protected final int fieldCount() { |
| return fieldTypes.size(); |
| } |
| |
| protected ClassSpecializer<T,K,S> outer() { |
| return ClassSpecializer.this; |
| } |
| |
| protected final boolean isResolved() { |
| return speciesCode != null && factories != null && !factories.isEmpty(); |
| } |
| |
| @Override public String toString() { |
| return metaType.getSimpleName() + "[" + key.toString() + " => " + (isResolved() ? speciesCode.getSimpleName() : "UNRESOLVED") + "]"; |
| } |
| |
| @Override |
| public int hashCode() { |
| return key.hashCode(); |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (!(obj instanceof ClassSpecializer.SpeciesData)) { |
| return false; |
| } |
| @SuppressWarnings("rawtypes") |
| ClassSpecializer.SpeciesData that = (ClassSpecializer.SpeciesData) obj; |
| return this.outer() == that.outer() && this.key.equals(that.key); |
| } |
| |
| /** Throws NPE if this species is not yet resolved. */ |
| protected final Class<? extends T> speciesCode() { |
| return Objects.requireNonNull(speciesCode); |
| } |
| |
| /** |
| * Return a {@link MethodHandle} which can get the indexed field of this species. |
| * The return type is the type of the species field it accesses. |
| * The argument type is the {@code fieldHolder} class of this species. |
| */ |
| protected MethodHandle getter(int i) { |
| return getters.get(i); |
| } |
| |
| /** |
| * Return a {@link LambdaForm.Name} containing a {@link LambdaForm.NamedFunction} that |
| * represents a MH bound to a generic invoker, which in turn forwards to the corresponding |
| * getter. |
| */ |
| protected LambdaForm.NamedFunction getterFunction(int i) { |
| LambdaForm.NamedFunction nf = nominalGetters.get(i); |
| assert(nf.memberDeclaringClassOrNull() == speciesCode()); |
| assert(nf.returnType() == BasicType.basicType(fieldTypes.get(i))); |
| return nf; |
| } |
| |
| protected List<LambdaForm.NamedFunction> getterFunctions() { |
| return nominalGetters; |
| } |
| |
| protected List<MethodHandle> getters() { |
| return getters; |
| } |
| |
| protected MethodHandle factory() { |
| return factories.get(0); |
| } |
| |
| protected MethodHandle transformHelper(int whichtm) { |
| MethodHandle mh = transformHelpers[whichtm]; |
| if (mh != null) return mh; |
| mh = deriveTransformHelper(transformMethods().get(whichtm), whichtm); |
| // Do a little type checking before we start using the MH. |
| // (It will be called with invokeBasic, so this is our only chance.) |
| final MethodType mt = transformHelperType(whichtm); |
| mh = mh.asType(mt); |
| return transformHelpers[whichtm] = mh; |
| } |
| |
| private final MethodType transformHelperType(int whichtm) { |
| MemberName tm = transformMethods().get(whichtm); |
| ArrayList<Class<?>> args = new ArrayList<>(); |
| ArrayList<Class<?>> fields = new ArrayList<>(); |
| Collections.addAll(args, tm.getParameterTypes()); |
| fields.addAll(fieldTypes()); |
| List<Class<?>> helperArgs = deriveTransformHelperArguments(tm, whichtm, args, fields); |
| return MethodType.methodType(tm.getReturnType(), helperArgs); |
| } |
| |
| // Hooks for subclasses: |
| |
| /** |
| * Given a key, derive the list of field types, which all instances of this |
| * species must store. |
| */ |
| protected abstract List<Class<?>> deriveFieldTypes(K key); |
| |
| /** |
| * Given the index of a method in the transforms list, supply a factory |
| * method that takes the arguments of the transform, plus the local fields, |
| * and produce a value of the required type. |
| * You can override this to return null or throw if there are no transforms. |
| * This method exists so that the transforms can be "grown" lazily. |
| * This is necessary if the transform *adds* a field to an instance, |
| * which sometimes requires the creation, on the fly, of an extended species. |
| * This method is only called once for any particular parameter. |
| * The species caches the result in a private array. |
| * |
| * @param transform the transform being implemented |
| * @param whichtm the index of that transform in the original list of transforms |
| * @return the method handle which creates a new result from a mix of transform |
| * arguments and field values |
| */ |
| protected abstract MethodHandle deriveTransformHelper(MemberName transform, int whichtm); |
| |
| /** |
| * During code generation, this method is called once per transform to determine |
| * what is the mix of arguments to hand to the transform-helper. The bytecode |
| * which marshals these arguments is open-coded in the species-specific transform. |
| * The two lists are of opaque objects, which you shouldn't do anything with besides |
| * reordering them into the output list. (They are both mutable, to make editing |
| * easier.) The imputed types of the args correspond to the transform's parameter |
| * list, while the imputed types of the fields correspond to the species field types. |
| * After code generation, this method may be called occasionally by error-checking code. |
| * |
| * @param transform the transform being implemented |
| * @param whichtm the index of that transform in the original list of transforms |
| * @param args a list of opaque objects representing the incoming transform arguments |
| * @param fields a list of opaque objects representing the field values of the receiver |
| * @param <X> the common element type of the various lists |
| * @return a new list |
| */ |
| protected abstract <X> List<X> deriveTransformHelperArguments(MemberName transform, int whichtm, |
| List<X> args, List<X> fields); |
| |
| /** Given a key, generate the name of the class which implements the species for that key. |
| * This algorithm must be stable. |
| * |
| * @return class name, which by default is {@code outer().topClass().getName() + "$Species_" + deriveTypeString(key)} |
| */ |
| protected String deriveClassName() { |
| return outer().topClass().getName() + "$Species_" + deriveTypeString(); |
| } |
| |
| /** |
| * Default implementation collects basic type characters, |
| * plus possibly type names, if some types don't correspond |
| * to basic types. |
| * |
| * @return a string suitable for use in a class name |
| */ |
| protected String deriveTypeString() { |
| List<Class<?>> types = fieldTypes(); |
| StringBuilder buf = new StringBuilder(); |
| StringBuilder end = new StringBuilder(); |
| for (Class<?> type : types) { |
| BasicType basicType = BasicType.basicType(type); |
| if (basicType.basicTypeClass() == type) { |
| buf.append(basicType.basicTypeChar()); |
| } else { |
| buf.append('V'); |
| end.append(classSig(type)); |
| } |
| } |
| String typeString; |
| if (end.length() > 0) { |
| typeString = BytecodeName.toBytecodeName(buf.append("_").append(end).toString()); |
| } else { |
| typeString = buf.toString(); |
| } |
| return LambdaForm.shortenSignature(typeString); |
| } |
| |
| /** |
| * Report what immediate super-class to use for the concrete class of this species. |
| * Normally this is {@code topClass}, but if that is an interface, the factory must override. |
| * The super-class must provide a constructor which takes the {@code baseConstructorType} arguments, if any. |
| * This hook also allows the code generator to use more than one canned supertype for species. |
| * |
| * @return the super-class of the class to be generated |
| */ |
| protected Class<? extends T> deriveSuperClass() { |
| final Class<T> topc = topClass(); |
| if (!topClassIsSuper) { |
| try { |
| final Constructor<T> con = reflectConstructor(topc, baseConstructorType().parameterArray()); |
| if (!topc.isInterface() && !Modifier.isPrivate(con.getModifiers())) { |
| topClassIsSuper = true; |
| } |
| } catch (Exception|InternalError ex) { |
| // fall through... |
| } |
| if (!topClassIsSuper) { |
| throw newInternalError("must override if the top class cannot serve as a super class"); |
| } |
| } |
| return topc; |
| } |
| } |
| |
| protected abstract S newSpeciesData(K key); |
| |
| protected K topSpeciesKey() { |
| return null; // null means don't report a top species |
| } |
| |
| /** |
| * Code generation support for instances. |
| * Subclasses can modify the behavior. |
| */ |
| public class Factory { |
| /** |
| * Constructs a factory. |
| */ |
| Factory() {} |
| |
| /** |
| * Get a concrete subclass of the top class for a given combination of bound types. |
| * |
| * @param speciesData the species requiring the class, not yet linked |
| * @return a linked version of the same species |
| */ |
| S loadSpecies(S speciesData) { |
| String className = speciesData.deriveClassName(); |
| assert(className.indexOf('/') < 0) : className; |
| Class<?> salvage = null; |
| try { |
| salvage = BootLoader.loadClassOrNull(className); |
| } catch (Error ex) { |
| // ignore |
| } finally { |
| traceSpeciesType(className, salvage); |
| } |
| final Class<? extends T> speciesCode; |
| if (salvage != null) { |
| speciesCode = salvage.asSubclass(topClass()); |
| linkSpeciesDataToCode(speciesData, speciesCode); |
| linkCodeToSpeciesData(speciesCode, speciesData, true); |
| } else { |
| // Not pregenerated, generate the class |
| try { |
| speciesCode = generateConcreteSpeciesCode(className, speciesData); |
| // This operation causes a lot of churn: |
| linkSpeciesDataToCode(speciesData, speciesCode); |
| // This operation commits the relation, but causes little churn: |
| linkCodeToSpeciesData(speciesCode, speciesData, false); |
| } catch (Error ex) { |
| // We can get here if there is a race condition loading a class. |
| // Or maybe we are out of resources. Back out of the CHM.get and retry. |
| throw ex; |
| } |
| } |
| |
| if (!speciesData.isResolved()) { |
| throw newInternalError("bad species class linkage for " + className + ": " + speciesData); |
| } |
| assert(speciesData == loadSpeciesDataFromCode(speciesCode)); |
| return speciesData; |
| } |
| |
| /** |
| * Generate a concrete subclass of the top class for a given combination of bound types. |
| * |
| * A concrete species subclass roughly matches the following schema: |
| * |
| * <pre> |
| * class Species_[[types]] extends [[T]] { |
| * final [[S]] speciesData() { return ... } |
| * static [[T]] make([[fields]]) { return ... } |
| * [[fields]] |
| * final [[T]] transform([[args]]) { return ... } |
| * } |
| * </pre> |
| * |
| * The {@code [[types]]} signature is precisely the key for the species. |
| * |
| * The {@code [[fields]]} section consists of one field definition per character in |
| * the type signature, adhering to the naming schema described in the definition of |
| * {@link #chooseFieldName}. |
| * |
| * For example, a concrete species for two references and one integral bound value |
| * has a shape like the following: |
| * |
| * <pre> |
| * class TopClass { |
| * ... |
| * private static final class Species_LLI extends TopClass { |
| * final Object argL0; |
| * final Object argL1; |
| * final int argI2; |
| * private Species_LLI(CT ctarg, ..., Object argL0, Object argL1, int argI2) { |
| * super(ctarg, ...); |
| * this.argL0 = argL0; |
| * this.argL1 = argL1; |
| * this.argI2 = argI2; |
| * } |
| * final SpeciesData speciesData() { return BMH_SPECIES; } |
| * @Stable static SpeciesData BMH_SPECIES; // injected afterwards |
| * static TopClass make(CT ctarg, ..., Object argL0, Object argL1, int argI2) { |
| * return new Species_LLI(ctarg, ..., argL0, argL1, argI2); |
| * } |
| * final TopClass copyWith(CT ctarg, ...) { |
| * return new Species_LLI(ctarg, ..., argL0, argL1, argI2); |
| * } |
| * // two transforms, for the sake of illustration: |
| * final TopClass copyWithExtendL(CT ctarg, ..., Object narg) { |
| * return BMH_SPECIES.transform(L_TYPE).invokeBasic(ctarg, ..., argL0, argL1, argI2, narg); |
| * } |
| * final TopClass copyWithExtendI(CT ctarg, ..., int narg) { |
| * return BMH_SPECIES.transform(I_TYPE).invokeBasic(ctarg, ..., argL0, argL1, argI2, narg); |
| * } |
| * } |
| * } |
| * </pre> |
| * |
| * @param className of the species |
| * @param speciesData what species we are generating |
| * @return the generated concrete TopClass class |
| */ |
| @SuppressWarnings("removal") |
| Class<? extends T> generateConcreteSpeciesCode(String className, ClassSpecializer<T,K,S>.SpeciesData speciesData) { |
| byte[] classFile = generateConcreteSpeciesCodeFile(className, speciesData); |
| |
| // load class |
| InvokerBytecodeGenerator.maybeDump(classBCName(className), classFile); |
| ClassLoader cl = topClass.getClassLoader(); |
| ProtectionDomain pd = null; |
| if (cl != null) { |
| pd = AccessController.doPrivileged( |
| new PrivilegedAction<>() { |
| @Override |
| public ProtectionDomain run() { |
| return topClass().getProtectionDomain(); |
| } |
| }); |
| } |
| Class<?> speciesCode = SharedSecrets.getJavaLangAccess() |
| .defineClass(cl, className, classFile, pd, "_ClassSpecializer_generateConcreteSpeciesCode"); |
| return speciesCode.asSubclass(topClass()); |
| } |
| |
| // These are named like constants because there is only one per specialization scheme: |
| private final String SPECIES_DATA = classBCName(metaType); |
| private final String SPECIES_DATA_SIG = classSig(SPECIES_DATA); |
| private final String SPECIES_DATA_NAME = sdAccessor.getName(); |
| private final int SPECIES_DATA_MODS = sdAccessor.getModifiers(); |
| private final List<String> TRANSFORM_NAMES; // derived from transformMethods |
| private final List<MethodType> TRANSFORM_TYPES; |
| private final List<Integer> TRANSFORM_MODS; |
| { |
| // Tear apart transformMethods to get the names, types, and modifiers. |
| List<String> tns = new ArrayList<>(); |
| List<MethodType> tts = new ArrayList<>(); |
| List<Integer> tms = new ArrayList<>(); |
| for (int i = 0; i < transformMethods.size(); i++) { |
| MemberName tm = transformMethods.get(i); |
| tns.add(tm.getName()); |
| final MethodType tt = tm.getMethodType(); |
| tts.add(tt); |
| tms.add(tm.getModifiers()); |
| } |
| TRANSFORM_NAMES = List.of(tns.toArray(new String[0])); |
| TRANSFORM_TYPES = List.of(tts.toArray(new MethodType[0])); |
| TRANSFORM_MODS = List.of(tms.toArray(new Integer[0])); |
| } |
| private static final int ACC_PPP = ACC_PUBLIC | ACC_PRIVATE | ACC_PROTECTED; |
| |
| /*non-public*/ |
| byte[] generateConcreteSpeciesCodeFile(String className0, ClassSpecializer<T,K,S>.SpeciesData speciesData) { |
| final String className = classBCName(className0); |
| final String superClassName = classBCName(speciesData.deriveSuperClass()); |
| |
| final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS + ClassWriter.COMPUTE_FRAMES); |
| final int NOT_ACC_PUBLIC = 0; // not ACC_PUBLIC |
| cw.visit(V1_6, NOT_ACC_PUBLIC + ACC_FINAL + ACC_SUPER, className, null, superClassName, null); |
| |
| final String sourceFile = className.substring(className.lastIndexOf('.')+1); |
| cw.visitSource(sourceFile, null); |
| |
| // emit static types and BMH_SPECIES fields |
| FieldVisitor fw = cw.visitField(NOT_ACC_PUBLIC + ACC_STATIC, sdFieldName, SPECIES_DATA_SIG, null, null); |
| fw.visitAnnotation(STABLE_SIG, true); |
| fw.visitEnd(); |
| |
| // handy holder for dealing with groups of typed values (ctor arguments and fields) |
| class Var { |
| final int index; |
| final String name; |
| final Class<?> type; |
| final String desc; |
| final BasicType basicType; |
| final int slotIndex; |
| Var(int index, int slotIndex) { |
| this.index = index; |
| this.slotIndex = slotIndex; |
| name = null; type = null; desc = null; |
| basicType = BasicType.V_TYPE; |
| } |
| Var(String name, Class<?> type, Var prev) { |
| int slotIndex = prev.nextSlotIndex(); |
| int index = prev.nextIndex(); |
| if (name == null) name = "x"; |
| if (name.endsWith("#")) |
| name = name.substring(0, name.length()-1) + index; |
| assert(!type.equals(void.class)); |
| String desc = classSig(type); |
| BasicType basicType = BasicType.basicType(type); |
| this.index = index; |
| this.name = name; |
| this.type = type; |
| this.desc = desc; |
| this.basicType = basicType; |
| this.slotIndex = slotIndex; |
| } |
| Var lastOf(List<Var> vars) { |
| int n = vars.size(); |
| return (n == 0 ? this : vars.get(n-1)); |
| } |
| <X> List<Var> fromTypes(List<X> types) { |
| Var prev = this; |
| ArrayList<Var> result = new ArrayList<>(types.size()); |
| int i = 0; |
| for (X x : types) { |
| String vn = name; |
| Class<?> vt; |
| if (x instanceof Class) { |
| vt = (Class<?>) x; |
| // make the names friendlier if debugging |
| assert((vn = vn + "_" + (i++)) != null); |
| } else { |
| @SuppressWarnings("unchecked") |
| Var v = (Var) x; |
| vn = v.name; |
| vt = v.type; |
| } |
| prev = new Var(vn, vt, prev); |
| result.add(prev); |
| } |
| return result; |
| } |
| |
| int slotSize() { return basicType.basicTypeSlots(); } |
| int nextIndex() { return index + (slotSize() == 0 ? 0 : 1); } |
| int nextSlotIndex() { return slotIndex >= 0 ? slotIndex + slotSize() : slotIndex; } |
| boolean isInHeap() { return slotIndex < 0; } |
| void emitVarInstruction(int asmop, MethodVisitor mv) { |
| if (asmop == ALOAD) |
| asmop = typeLoadOp(basicType.basicTypeChar()); |
| else |
| throw new AssertionError("bad op="+asmop+" for desc="+desc); |
| mv.visitVarInsn(asmop, slotIndex); |
| } |
| public void emitFieldInsn(int asmop, MethodVisitor mv) { |
| mv.visitFieldInsn(asmop, className, name, desc); |
| } |
| } |
| |
| final Var NO_THIS = new Var(0, 0), |
| AFTER_THIS = new Var(0, 1), |
| IN_HEAP = new Var(0, -1); |
| |
| // figure out the field types |
| final List<Class<?>> fieldTypes = speciesData.fieldTypes(); |
| final List<Var> fields = new ArrayList<>(fieldTypes.size()); |
| { |
| Var nextF = IN_HEAP; |
| for (Class<?> ft : fieldTypes) { |
| String fn = chooseFieldName(ft, nextF.nextIndex()); |
| nextF = new Var(fn, ft, nextF); |
| fields.add(nextF); |
| } |
| } |
| |
| // emit bound argument fields |
| for (Var field : fields) { |
| cw.visitField(ACC_FINAL, field.name, field.desc, null, null).visitEnd(); |
| } |
| |
| MethodVisitor mv; |
| |
| // emit implementation of speciesData() |
| mv = cw.visitMethod((SPECIES_DATA_MODS & ACC_PPP) + ACC_FINAL, |
| SPECIES_DATA_NAME, "()" + SPECIES_DATA_SIG, null, null); |
| mv.visitCode(); |
| mv.visitFieldInsn(GETSTATIC, className, sdFieldName, SPECIES_DATA_SIG); |
| mv.visitInsn(ARETURN); |
| mv.visitMaxs(0, 0); |
| mv.visitEnd(); |
| |
| // figure out the constructor arguments |
| MethodType superCtorType = ClassSpecializer.this.baseConstructorType(); |
| MethodType thisCtorType = superCtorType.appendParameterTypes(fieldTypes); |
| |
| // emit constructor |
| { |
| mv = cw.visitMethod(ACC_PRIVATE, |
| "<init>", methodSig(thisCtorType), null, null); |
| mv.visitCode(); |
| mv.visitVarInsn(ALOAD, 0); // this |
| |
| final List<Var> ctorArgs = AFTER_THIS.fromTypes(superCtorType.parameterList()); |
| for (Var ca : ctorArgs) { |
| ca.emitVarInstruction(ALOAD, mv); |
| } |
| |
| // super(ca...) |
| mv.visitMethodInsn(INVOKESPECIAL, superClassName, |
| "<init>", methodSig(superCtorType), false); |
| |
| // store down fields |
| Var lastFV = AFTER_THIS.lastOf(ctorArgs); |
| for (Var f : fields) { |
| // this.argL1 = argL1 |
| mv.visitVarInsn(ALOAD, 0); // this |
| lastFV = new Var(f.name, f.type, lastFV); |
| lastFV.emitVarInstruction(ALOAD, mv); |
| f.emitFieldInsn(PUTFIELD, mv); |
| } |
| |
| mv.visitInsn(RETURN); |
| mv.visitMaxs(0, 0); |
| mv.visitEnd(); |
| } |
| |
| // emit make() ...factory method wrapping constructor |
| { |
| MethodType ftryType = thisCtorType.changeReturnType(topClass()); |
| mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_STATIC, |
| "make", methodSig(ftryType), null, null); |
| mv.visitCode(); |
| // make instance |
| mv.visitTypeInsn(NEW, className); |
| mv.visitInsn(DUP); |
| // load factory method arguments: ctarg... and arg... |
| for (Var v : NO_THIS.fromTypes(ftryType.parameterList())) { |
| v.emitVarInstruction(ALOAD, mv); |
| } |
| |
| // finally, invoke the constructor and return |
| mv.visitMethodInsn(INVOKESPECIAL, className, |
| "<init>", methodSig(thisCtorType), false); |
| mv.visitInsn(ARETURN); |
| mv.visitMaxs(0, 0); |
| mv.visitEnd(); |
| } |
| |
| // For each transform, emit the customized override of the transform method. |
| // This method mixes together some incoming arguments (from the transform's |
| // static type signature) with the field types themselves, and passes |
| // the resulting mish-mosh of values to a method handle produced by |
| // the species itself. (Typically this method handle is the factory |
| // method of this species or a related one.) |
| for (int whichtm = 0; whichtm < TRANSFORM_NAMES.size(); whichtm++) { |
| final String TNAME = TRANSFORM_NAMES.get(whichtm); |
| final MethodType TTYPE = TRANSFORM_TYPES.get(whichtm); |
| final int TMODS = TRANSFORM_MODS.get(whichtm); |
| mv = cw.visitMethod((TMODS & ACC_PPP) | ACC_FINAL, |
| TNAME, TTYPE.toMethodDescriptorString(), null, E_THROWABLE); |
| mv.visitCode(); |
| // return a call to the corresponding "transform helper", something like this: |
| // MY_SPECIES.transformHelper(whichtm).invokeBasic(ctarg, ..., argL0, ..., xarg) |
| mv.visitFieldInsn(GETSTATIC, className, |
| sdFieldName, SPECIES_DATA_SIG); |
| emitIntConstant(whichtm, mv); |
| mv.visitMethodInsn(INVOKEVIRTUAL, SPECIES_DATA, |
| "transformHelper", "(I)" + MH_SIG, false); |
| |
| List<Var> targs = AFTER_THIS.fromTypes(TTYPE.parameterList()); |
| List<Var> tfields = new ArrayList<>(fields); |
| // mix them up and load them for the transform helper: |
| List<Var> helperArgs = speciesData.deriveTransformHelperArguments(transformMethods.get(whichtm), whichtm, targs, tfields); |
| List<Class<?>> helperTypes = new ArrayList<>(helperArgs.size()); |
| for (Var ha : helperArgs) { |
| helperTypes.add(ha.basicType.basicTypeClass()); |
| if (ha.isInHeap()) { |
| assert(tfields.contains(ha)); |
| mv.visitVarInsn(ALOAD, 0); |
| ha.emitFieldInsn(GETFIELD, mv); |
| } else { |
| assert(targs.contains(ha)); |
| ha.emitVarInstruction(ALOAD, mv); |
| } |
| } |
| |
| // jump into the helper (which is probably a factory method) |
| final Class<?> rtype = TTYPE.returnType(); |
| final BasicType rbt = BasicType.basicType(rtype); |
| MethodType invokeBasicType = MethodType.methodType(rbt.basicTypeClass(), helperTypes); |
| mv.visitMethodInsn(INVOKEVIRTUAL, MH, |
| "invokeBasic", methodSig(invokeBasicType), false); |
| if (rbt == BasicType.L_TYPE) { |
| mv.visitTypeInsn(CHECKCAST, classBCName(rtype)); |
| mv.visitInsn(ARETURN); |
| } else { |
| throw newInternalError("NYI: transform of type "+rtype); |
| } |
| mv.visitMaxs(0, 0); |
| mv.visitEnd(); |
| } |
| |
| cw.visitEnd(); |
| |
| return cw.toByteArray(); |
| } |
| |
| private int typeLoadOp(char t) { |
| switch (t) { |
| case 'L': return ALOAD; |
| case 'I': return ILOAD; |
| case 'J': return LLOAD; |
| case 'F': return FLOAD; |
| case 'D': return DLOAD; |
| default : throw newInternalError("unrecognized type " + t); |
| } |
| } |
| |
| private void emitIntConstant(int con, MethodVisitor mv) { |
| if (ICONST_M1 - ICONST_0 <= con && con <= ICONST_5 - ICONST_0) |
| mv.visitInsn(ICONST_0 + con); |
| else if (con == (byte) con) |
| mv.visitIntInsn(BIPUSH, con); |
| else if (con == (short) con) |
| mv.visitIntInsn(SIPUSH, con); |
| else { |
| mv.visitLdcInsn(con); |
| } |
| |
| } |
| |
| // |
| // Getter MH generation. |
| // |
| |
| private MethodHandle findGetter(Class<?> speciesCode, List<Class<?>> types, int index) { |
| Class<?> fieldType = types.get(index); |
| String fieldName = chooseFieldName(fieldType, index); |
| try { |
| return IMPL_LOOKUP.findGetter(speciesCode, fieldName, fieldType); |
| } catch (NoSuchFieldException | IllegalAccessException e) { |
| throw newInternalError(e); |
| } |
| } |
| |
| private List<MethodHandle> findGetters(Class<?> speciesCode, List<Class<?>> types) { |
| MethodHandle[] mhs = new MethodHandle[types.size()]; |
| for (int i = 0; i < mhs.length; ++i) { |
| mhs[i] = findGetter(speciesCode, types, i); |
| assert(mhs[i].internalMemberName().getDeclaringClass() == speciesCode); |
| } |
| return List.of(mhs); |
| } |
| |
| private List<MethodHandle> findFactories(Class<? extends T> speciesCode, List<Class<?>> types) { |
| MethodHandle[] mhs = new MethodHandle[1]; |
| mhs[0] = findFactory(speciesCode, types); |
| return List.of(mhs); |
| } |
| |
| List<LambdaForm.NamedFunction> makeNominalGetters(List<Class<?>> types, List<MethodHandle> getters) { |
| LambdaForm.NamedFunction[] nfs = new LambdaForm.NamedFunction[types.size()]; |
| for (int i = 0; i < nfs.length; ++i) { |
| nfs[i] = new LambdaForm.NamedFunction(getters.get(i)); |
| } |
| return List.of(nfs); |
| } |
| |
| // |
| // Auxiliary methods. |
| // |
| |
| protected void linkSpeciesDataToCode(ClassSpecializer<T,K,S>.SpeciesData speciesData, Class<? extends T> speciesCode) { |
| speciesData.speciesCode = speciesCode.asSubclass(topClass); |
| final List<Class<?>> types = speciesData.fieldTypes; |
| speciesData.factories = this.findFactories(speciesCode, types); |
| speciesData.getters = this.findGetters(speciesCode, types); |
| speciesData.nominalGetters = this.makeNominalGetters(types, speciesData.getters); |
| } |
| |
| private Field reflectSDField(Class<? extends T> speciesCode) { |
| final Field field = reflectField(speciesCode, sdFieldName); |
| assert(field.getType() == metaType); |
| assert(Modifier.isStatic(field.getModifiers())); |
| return field; |
| } |
| |
| private S readSpeciesDataFromCode(Class<? extends T> speciesCode) { |
| try { |
| MemberName sdField = IMPL_LOOKUP.resolveOrFail(REF_getStatic, speciesCode, sdFieldName, metaType); |
| Object base = MethodHandleNatives.staticFieldBase(sdField); |
| long offset = MethodHandleNatives.staticFieldOffset(sdField); |
| UNSAFE.loadFence(); |
| return metaType.cast(UNSAFE.getReference(base, offset)); |
| } catch (Error err) { |
| throw err; |
| } catch (Exception ex) { |
| throw newInternalError("Failed to load speciesData from speciesCode: " + speciesCode.getName(), ex); |
| } catch (Throwable t) { |
| throw uncaughtException(t); |
| } |
| } |
| |
| protected S loadSpeciesDataFromCode(Class<? extends T> speciesCode) { |
| if (speciesCode == topClass()) { |
| return topSpecies; |
| } |
| S result = readSpeciesDataFromCode(speciesCode); |
| if (result.outer() != ClassSpecializer.this) { |
| throw newInternalError("wrong class"); |
| } |
| return result; |
| } |
| |
| protected void linkCodeToSpeciesData(Class<? extends T> speciesCode, ClassSpecializer<T,K,S>.SpeciesData speciesData, boolean salvage) { |
| try { |
| assert(readSpeciesDataFromCode(speciesCode) == null || |
| (salvage && readSpeciesDataFromCode(speciesCode).equals(speciesData))); |
| |
| MemberName sdField = IMPL_LOOKUP.resolveOrFail(REF_putStatic, speciesCode, sdFieldName, metaType); |
| Object base = MethodHandleNatives.staticFieldBase(sdField); |
| long offset = MethodHandleNatives.staticFieldOffset(sdField); |
| UNSAFE.storeFence(); |
| UNSAFE.putReference(base, offset, speciesData); |
| UNSAFE.storeFence(); |
| } catch (Error err) { |
| throw err; |
| } catch (Exception ex) { |
| throw newInternalError("Failed to link speciesData to speciesCode: " + speciesCode.getName(), ex); |
| } catch (Throwable t) { |
| throw uncaughtException(t); |
| } |
| } |
| |
| /** |
| * Field names in concrete species classes adhere to this pattern: |
| * type + index, where type is a single character (L, I, J, F, D). |
| * The factory subclass can customize this. |
| * The name is purely cosmetic, since it applies to a private field. |
| */ |
| protected String chooseFieldName(Class<?> type, int index) { |
| BasicType bt = BasicType.basicType(type); |
| return "" + bt.basicTypeChar() + index; |
| } |
| |
| MethodHandle findFactory(Class<? extends T> speciesCode, List<Class<?>> types) { |
| final MethodType type = baseConstructorType().changeReturnType(topClass()).appendParameterTypes(types); |
| try { |
| return IMPL_LOOKUP.findStatic(speciesCode, "make", type); |
| } catch (NoSuchMethodException | IllegalAccessException | IllegalArgumentException | TypeNotPresentException e) { |
| throw newInternalError(e); |
| } |
| } |
| } |
| |
| /** Hook that virtualizes the Factory class, allowing subclasses to extend it. */ |
| protected Factory makeFactory() { |
| return new Factory(); |
| } |
| |
| |
| // Other misc helpers: |
| private static final String MH = "java/lang/invoke/MethodHandle"; |
| private static final String MH_SIG = "L" + MH + ";"; |
| private static final String STABLE = "jdk/internal/vm/annotation/Stable"; |
| private static final String STABLE_SIG = "L" + STABLE + ";"; |
| private static final String[] E_THROWABLE = new String[] { "java/lang/Throwable" }; |
| static { |
| assert(MH_SIG.equals(classSig(MethodHandle.class))); |
| assert(MH.equals(classBCName(MethodHandle.class))); |
| } |
| |
| static String methodSig(MethodType mt) { |
| return mt.toMethodDescriptorString(); |
| } |
| static String classSig(Class<?> cls) { |
| if (cls.isPrimitive() || cls.isArray()) |
| return MethodType.methodType(cls).toMethodDescriptorString().substring(2); |
| return classSig(classBCName(cls)); |
| } |
| static String classSig(String bcName) { |
| assert(bcName.indexOf('.') < 0); |
| assert(!bcName.endsWith(";")); |
| assert(!bcName.startsWith("[")); |
| return "L" + bcName + ";"; |
| } |
| static String classBCName(Class<?> cls) { |
| return classBCName(className(cls)); |
| } |
| static String classBCName(String str) { |
| assert(str.indexOf('/') < 0) : str; |
| return str.replace('.', '/'); |
| } |
| static String className(Class<?> cls) { |
| assert(!cls.isArray() && !cls.isPrimitive()); |
| return cls.getName(); |
| } |
| } |
