--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/java.base/share/classes/java/lang/invoke/BoundMethodHandle.java Sun Aug 17 15:54:13 2014 +0100
@@ -0,0 +1,827 @@
+/*
+ * Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. 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 static jdk.internal.org.objectweb.asm.Opcodes.*;
+import static java.lang.invoke.LambdaForm.*;
+import static java.lang.invoke.LambdaForm.BasicType.*;
+import static java.lang.invoke.MethodHandleStatics.*;
+
+import java.lang.invoke.LambdaForm.NamedFunction;
+import java.lang.invoke.MethodHandles.Lookup;
+import java.lang.reflect.Field;
+import java.util.Arrays;
+import java.util.HashMap;
+
+import sun.invoke.util.ValueConversions;
+import sun.invoke.util.Wrapper;
+
+import jdk.internal.org.objectweb.asm.ClassWriter;
+import jdk.internal.org.objectweb.asm.MethodVisitor;
+import jdk.internal.org.objectweb.asm.Type;
+
+/**
+ * The flavor of method handle which emulates an invoke instruction
+ * on a predetermined argument. The JVM dispatches to the correct method
+ * when the handle is created, not when it is invoked.
+ *
+ * All bound arguments are encapsulated in dedicated species.
+ */
+/* non-public */ abstract class BoundMethodHandle extends MethodHandle {
+
+ /* non-public */ BoundMethodHandle(MethodType type, LambdaForm form) {
+ super(type, form);
+ }
+
+ //
+ // BMH API and internals
+ //
+
+ static MethodHandle bindSingle(MethodType type, LambdaForm form, BasicType xtype, Object x) {
+ // for some type signatures, there exist pre-defined concrete BMH classes
+ try {
+ switch (xtype) {
+ case L_TYPE:
+ if (true) return bindSingle(type, form, x); // Use known fast path.
+ return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(L_TYPE).constructor[0].invokeBasic(type, form, x);
+ case I_TYPE:
+ return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(I_TYPE).constructor[0].invokeBasic(type, form, ValueConversions.widenSubword(x));
+ case J_TYPE:
+ return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(J_TYPE).constructor[0].invokeBasic(type, form, (long) x);
+ case F_TYPE:
+ return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(F_TYPE).constructor[0].invokeBasic(type, form, (float) x);
+ case D_TYPE:
+ return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(D_TYPE).constructor[0].invokeBasic(type, form, (double) x);
+ default : throw newInternalError("unexpected xtype: " + xtype);
+ }
+ } catch (Throwable t) {
+ throw newInternalError(t);
+ }
+ }
+
+ static MethodHandle bindSingle(MethodType type, LambdaForm form, Object x) {
+ return new Species_L(type, form, x);
+ }
+
+ MethodHandle cloneExtend(MethodType type, LambdaForm form, BasicType xtype, Object x) {
+ try {
+ switch (xtype) {
+ case L_TYPE: return copyWithExtendL(type, form, x);
+ case I_TYPE: return copyWithExtendI(type, form, ValueConversions.widenSubword(x));
+ case J_TYPE: return copyWithExtendJ(type, form, (long) x);
+ case F_TYPE: return copyWithExtendF(type, form, (float) x);
+ case D_TYPE: return copyWithExtendD(type, form, (double) x);
+ }
+ } catch (Throwable t) {
+ throw newInternalError(t);
+ }
+ throw newInternalError("unexpected type: " + xtype);
+ }
+
+ @Override
+ MethodHandle bindArgument(int pos, BasicType basicType, Object value) {
+ MethodType type = type().dropParameterTypes(pos, pos+1);
+ LambdaForm form = internalForm().bind(1+pos, speciesData());
+ return cloneExtend(type, form, basicType, value);
+ }
+
+ @Override
+ MethodHandle dropArguments(MethodType srcType, int pos, int drops) {
+ LambdaForm form = internalForm().addArguments(pos, srcType.parameterList().subList(pos, pos + drops));
+ try {
+ return copyWith(srcType, form);
+ } catch (Throwable t) {
+ throw newInternalError(t);
+ }
+ }
+
+ @Override
+ MethodHandle permuteArguments(MethodType newType, int[] reorder) {
+ try {
+ return copyWith(newType, form.permuteArguments(1, reorder, basicTypes(newType.parameterList())));
+ } catch (Throwable t) {
+ throw newInternalError(t);
+ }
+ }
+
+ /**
+ * Return the {@link SpeciesData} instance representing this BMH species. All subclasses must provide a
+ * static field containing this value, and they must accordingly implement this method.
+ */
+ /*non-public*/ abstract SpeciesData speciesData();
+
+ /**
+ * Return the number of fields in this BMH. Equivalent to speciesData().fieldCount().
+ */
+ /*non-public*/ abstract int fieldCount();
+
+ @Override
+ final Object internalProperties() {
+ return "/BMH="+internalValues();
+ }
+
+ @Override
+ final Object internalValues() {
+ Object[] boundValues = new Object[speciesData().fieldCount()];
+ for (int i = 0; i < boundValues.length; ++i) {
+ boundValues[i] = arg(i);
+ }
+ return Arrays.asList(boundValues);
+ }
+
+ /*non-public*/ final Object arg(int i) {
+ try {
+ switch (speciesData().fieldType(i)) {
+ case L_TYPE: return speciesData().getters[i].invokeBasic(this);
+ case I_TYPE: return (int) speciesData().getters[i].invokeBasic(this);
+ case J_TYPE: return (long) speciesData().getters[i].invokeBasic(this);
+ case F_TYPE: return (float) speciesData().getters[i].invokeBasic(this);
+ case D_TYPE: return (double) speciesData().getters[i].invokeBasic(this);
+ }
+ } catch (Throwable ex) {
+ throw newInternalError(ex);
+ }
+ throw new InternalError("unexpected type: " + speciesData().typeChars+"."+i);
+ }
+
+ //
+ // cloning API
+ //
+
+ /*non-public*/ abstract BoundMethodHandle copyWith(MethodType mt, LambdaForm lf);
+ /*non-public*/ abstract BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg);
+ /*non-public*/ abstract BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg);
+ /*non-public*/ abstract BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg);
+ /*non-public*/ abstract BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg);
+ /*non-public*/ abstract BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg);
+
+ // The following is a grossly irregular hack:
+ @Override MethodHandle reinvokerTarget() {
+ try {
+ return (MethodHandle) arg(0);
+ } catch (Throwable ex) {
+ throw newInternalError(ex);
+ }
+ }
+
+ //
+ // concrete BMH classes required to close bootstrap loops
+ //
+
+ private // make it private to force users to access the enclosing class first
+ static final class Species_L extends BoundMethodHandle {
+ final Object argL0;
+ private Species_L(MethodType mt, LambdaForm lf, Object argL0) {
+ super(mt, lf);
+ this.argL0 = argL0;
+ }
+ // The following is a grossly irregular hack:
+ @Override MethodHandle reinvokerTarget() { return (MethodHandle) argL0; }
+ @Override
+ /*non-public*/ SpeciesData speciesData() {
+ return SPECIES_DATA;
+ }
+ @Override
+ /*non-public*/ int fieldCount() {
+ return 1;
+ }
+ /*non-public*/ static final SpeciesData SPECIES_DATA = SpeciesData.getForClass("L", Species_L.class);
+ /*non-public*/ static BoundMethodHandle make(MethodType mt, LambdaForm lf, Object argL0) {
+ return new Species_L(mt, lf, argL0);
+ }
+ @Override
+ /*non-public*/ final BoundMethodHandle copyWith(MethodType mt, LambdaForm lf) {
+ return new Species_L(mt, lf, argL0);
+ }
+ @Override
+ /*non-public*/ final BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg) {
+ try {
+ return (BoundMethodHandle) SPECIES_DATA.extendWith(L_TYPE).constructor[0].invokeBasic(mt, lf, argL0, narg);
+ } catch (Throwable ex) {
+ throw uncaughtException(ex);
+ }
+ }
+ @Override
+ /*non-public*/ final BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg) {
+ try {
+ return (BoundMethodHandle) SPECIES_DATA.extendWith(I_TYPE).constructor[0].invokeBasic(mt, lf, argL0, narg);
+ } catch (Throwable ex) {
+ throw uncaughtException(ex);
+ }
+ }
+ @Override
+ /*non-public*/ final BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg) {
+ try {
+ return (BoundMethodHandle) SPECIES_DATA.extendWith(J_TYPE).constructor[0].invokeBasic(mt, lf, argL0, narg);
+ } catch (Throwable ex) {
+ throw uncaughtException(ex);
+ }
+ }
+ @Override
+ /*non-public*/ final BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg) {
+ try {
+ return (BoundMethodHandle) SPECIES_DATA.extendWith(F_TYPE).constructor[0].invokeBasic(mt, lf, argL0, narg);
+ } catch (Throwable ex) {
+ throw uncaughtException(ex);
+ }
+ }
+ @Override
+ /*non-public*/ final BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg) {
+ try {
+ return (BoundMethodHandle) SPECIES_DATA.extendWith(D_TYPE).constructor[0].invokeBasic(mt, lf, argL0, narg);
+ } catch (Throwable ex) {
+ throw uncaughtException(ex);
+ }
+ }
+ }
+
+ //
+ // BMH species meta-data
+ //
+
+ /**
+ * Meta-data wrapper for concrete BMH types.
+ * Each BMH type corresponds to a given sequence of basic field types (LIJFD).
+ * The fields are immutable; their values are fully specified at object construction.
+ * Each BMH type supplies an array of getter functions which may be used in lambda forms.
+ * A BMH is constructed by cloning a shorter BMH and adding one or more new field values.
+ * As a degenerate and common case, the "shorter BMH" can be missing, and contributes zero prior fields.
+ */
+ static class SpeciesData {
+ final String typeChars;
+ final BasicType[] typeCodes;
+ final Class<? extends BoundMethodHandle> clazz;
+ // Bootstrapping requires circular relations MH -> BMH -> SpeciesData -> MH
+ // Therefore, we need a non-final link in the chain. Use array elements.
+ final MethodHandle[] constructor;
+ final MethodHandle[] getters;
+ final NamedFunction[] nominalGetters;
+ final SpeciesData[] extensions;
+
+ /*non-public*/ int fieldCount() {
+ return typeCodes.length;
+ }
+ /*non-public*/ BasicType fieldType(int i) {
+ return typeCodes[i];
+ }
+ /*non-public*/ char fieldTypeChar(int i) {
+ return typeChars.charAt(i);
+ }
+
+ public String toString() {
+ return "SpeciesData["+(isPlaceholder() ? "<placeholder>" : clazz.getSimpleName())+":"+typeChars+"]";
+ }
+
+ /**
+ * 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.
+ */
+ NamedFunction getterFunction(int i) {
+ return nominalGetters[i];
+ }
+
+ static final SpeciesData EMPTY = new SpeciesData("", BoundMethodHandle.class);
+
+ private SpeciesData(String types, Class<? extends BoundMethodHandle> clazz) {
+ this.typeChars = types;
+ this.typeCodes = basicTypes(types);
+ this.clazz = clazz;
+ if (!INIT_DONE) {
+ this.constructor = new MethodHandle[1]; // only one ctor
+ this.getters = new MethodHandle[types.length()];
+ this.nominalGetters = new NamedFunction[types.length()];
+ } else {
+ this.constructor = Factory.makeCtors(clazz, types, null);
+ this.getters = Factory.makeGetters(clazz, types, null);
+ this.nominalGetters = Factory.makeNominalGetters(types, null, this.getters);
+ }
+ this.extensions = new SpeciesData[ARG_TYPE_LIMIT];
+ }
+
+ private void initForBootstrap() {
+ assert(!INIT_DONE);
+ if (constructor[0] == null) {
+ String types = typeChars;
+ Factory.makeCtors(clazz, types, this.constructor);
+ Factory.makeGetters(clazz, types, this.getters);
+ Factory.makeNominalGetters(types, this.nominalGetters, this.getters);
+ }
+ }
+
+ private SpeciesData(String typeChars) {
+ // Placeholder only.
+ this.typeChars = typeChars;
+ this.typeCodes = basicTypes(typeChars);
+ this.clazz = null;
+ this.constructor = null;
+ this.getters = null;
+ this.nominalGetters = null;
+ this.extensions = null;
+ }
+ private boolean isPlaceholder() { return clazz == null; }
+
+ private static final HashMap<String, SpeciesData> CACHE = new HashMap<>();
+ static { CACHE.put("", EMPTY); } // make bootstrap predictable
+ private static final boolean INIT_DONE; // set after <clinit> finishes...
+
+ SpeciesData extendWith(byte type) {
+ return extendWith(BasicType.basicType(type));
+ }
+
+ SpeciesData extendWith(BasicType type) {
+ int ord = type.ordinal();
+ SpeciesData d = extensions[ord];
+ if (d != null) return d;
+ extensions[ord] = d = get(typeChars+type.basicTypeChar());
+ return d;
+ }
+
+ private static SpeciesData get(String types) {
+ // Acquire cache lock for query.
+ SpeciesData d = lookupCache(types);
+ if (!d.isPlaceholder())
+ return d;
+ synchronized (d) {
+ // Use synch. on the placeholder to prevent multiple instantiation of one species.
+ // Creating this class forces a recursive call to getForClass.
+ if (lookupCache(types).isPlaceholder())
+ Factory.generateConcreteBMHClass(types);
+ }
+ // Reacquire cache lock.
+ d = lookupCache(types);
+ // Class loading must have upgraded the cache.
+ assert(d != null && !d.isPlaceholder());
+ return d;
+ }
+ static SpeciesData getForClass(String types, Class<? extends BoundMethodHandle> clazz) {
+ // clazz is a new class which is initializing its SPECIES_DATA field
+ return updateCache(types, new SpeciesData(types, clazz));
+ }
+ private static synchronized SpeciesData lookupCache(String types) {
+ SpeciesData d = CACHE.get(types);
+ if (d != null) return d;
+ d = new SpeciesData(types);
+ assert(d.isPlaceholder());
+ CACHE.put(types, d);
+ return d;
+ }
+ private static synchronized SpeciesData updateCache(String types, SpeciesData d) {
+ SpeciesData d2;
+ assert((d2 = CACHE.get(types)) == null || d2.isPlaceholder());
+ assert(!d.isPlaceholder());
+ CACHE.put(types, d);
+ return d;
+ }
+
+ static {
+ // pre-fill the BMH speciesdata cache with BMH's inner classes
+ final Class<BoundMethodHandle> rootCls = BoundMethodHandle.class;
+ try {
+ for (Class<?> c : rootCls.getDeclaredClasses()) {
+ if (rootCls.isAssignableFrom(c)) {
+ final Class<? extends BoundMethodHandle> cbmh = c.asSubclass(BoundMethodHandle.class);
+ SpeciesData d = Factory.speciesDataFromConcreteBMHClass(cbmh);
+ assert(d != null) : cbmh.getName();
+ assert(d.clazz == cbmh);
+ assert(d == lookupCache(d.typeChars));
+ }
+ }
+ } catch (Throwable e) {
+ throw newInternalError(e);
+ }
+
+ for (SpeciesData d : CACHE.values()) {
+ d.initForBootstrap();
+ }
+ // Note: Do not simplify this, because INIT_DONE must not be
+ // a compile-time constant during bootstrapping.
+ INIT_DONE = Boolean.TRUE;
+ }
+ }
+
+ static SpeciesData getSpeciesData(String types) {
+ return SpeciesData.get(types);
+ }
+
+ /**
+ * Generation of concrete BMH classes.
+ *
+ * A concrete BMH species is fit for binding a number of values adhering to a
+ * given type pattern. Reference types are erased.
+ *
+ * BMH species are cached by type pattern.
+ *
+ * A BMH species has a number of fields with the concrete (possibly erased) types of
+ * bound values. Setters are provided as an API in BMH. Getters are exposed as MHs,
+ * which can be included as names in lambda forms.
+ */
+ static class Factory {
+
+ static final String JLO_SIG = "Ljava/lang/Object;";
+ static final String JLS_SIG = "Ljava/lang/String;";
+ static final String JLC_SIG = "Ljava/lang/Class;";
+ static final String MH = "java/lang/invoke/MethodHandle";
+ static final String MH_SIG = "L"+MH+";";
+ static final String BMH = "java/lang/invoke/BoundMethodHandle";
+ static final String BMH_SIG = "L"+BMH+";";
+ static final String SPECIES_DATA = "java/lang/invoke/BoundMethodHandle$SpeciesData";
+ static final String SPECIES_DATA_SIG = "L"+SPECIES_DATA+";";
+
+ static final String SPECIES_PREFIX_NAME = "Species_";
+ static final String SPECIES_PREFIX_PATH = BMH + "$" + SPECIES_PREFIX_NAME;
+
+ static final String BMHSPECIES_DATA_EWI_SIG = "(B)" + SPECIES_DATA_SIG;
+ static final String BMHSPECIES_DATA_GFC_SIG = "(" + JLS_SIG + JLC_SIG + ")" + SPECIES_DATA_SIG;
+ static final String MYSPECIES_DATA_SIG = "()" + SPECIES_DATA_SIG;
+ static final String VOID_SIG = "()V";
+ static final String INT_SIG = "()I";
+
+ static final String SIG_INCIPIT = "(Ljava/lang/invoke/MethodType;Ljava/lang/invoke/LambdaForm;";
+
+ static final String[] E_THROWABLE = new String[] { "java/lang/Throwable" };
+
+ /**
+ * Generate a concrete subclass of BMH for a given combination of bound types.
+ *
+ * A concrete BMH species adheres to the following schema:
+ *
+ * <pre>
+ * class Species_[[types]] extends BoundMethodHandle {
+ * [[fields]]
+ * final SpeciesData speciesData() { return SpeciesData.get("[[types]]"); }
+ * }
+ * </pre>
+ *
+ * The {@code [[types]]} signature is precisely the string that is passed to this
+ * method.
+ *
+ * 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 #makeFieldName}.
+ *
+ * For example, a concrete BMH species for two reference and one integral bound values
+ * would have the following shape:
+ *
+ * <pre>
+ * class BoundMethodHandle { ... private static
+ * final class Species_LLI extends BoundMethodHandle {
+ * final Object argL0;
+ * final Object argL1;
+ * final int argI2;
+ * private Species_LLI(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) {
+ * super(mt, lf);
+ * this.argL0 = argL0;
+ * this.argL1 = argL1;
+ * this.argI2 = argI2;
+ * }
+ * final SpeciesData speciesData() { return SPECIES_DATA; }
+ * final int fieldCount() { return 3; }
+ * static final SpeciesData SPECIES_DATA = SpeciesData.getForClass("LLI", Species_LLI.class);
+ * static BoundMethodHandle make(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) {
+ * return new Species_LLI(mt, lf, argL0, argL1, argI2);
+ * }
+ * final BoundMethodHandle copyWith(MethodType mt, LambdaForm lf) {
+ * return new Species_LLI(mt, lf, argL0, argL1, argI2);
+ * }
+ * final BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg) {
+ * return SPECIES_DATA.extendWith(L_TYPE).constructor[0].invokeBasic(mt, lf, argL0, argL1, argI2, narg);
+ * }
+ * final BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg) {
+ * return SPECIES_DATA.extendWith(I_TYPE).constructor[0].invokeBasic(mt, lf, argL0, argL1, argI2, narg);
+ * }
+ * final BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg) {
+ * return SPECIES_DATA.extendWith(J_TYPE).constructor[0].invokeBasic(mt, lf, argL0, argL1, argI2, narg);
+ * }
+ * final BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg) {
+ * return SPECIES_DATA.extendWith(F_TYPE).constructor[0].invokeBasic(mt, lf, argL0, argL1, argI2, narg);
+ * }
+ * public final BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg) {
+ * return SPECIES_DATA.extendWith(D_TYPE).constructor[0].invokeBasic(mt, lf, argL0, argL1, argI2, narg);
+ * }
+ * }
+ * </pre>
+ *
+ * @param types the type signature, wherein reference types are erased to 'L'
+ * @return the generated concrete BMH class
+ */
+ static Class<? extends BoundMethodHandle> generateConcreteBMHClass(String types) {
+ final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS + ClassWriter.COMPUTE_FRAMES);
+
+ String shortTypes = LambdaForm.shortenSignature(types);
+ final String className = SPECIES_PREFIX_PATH + shortTypes;
+ final String sourceFile = SPECIES_PREFIX_NAME + shortTypes;
+ final int NOT_ACC_PUBLIC = 0; // not ACC_PUBLIC
+ cw.visit(V1_6, NOT_ACC_PUBLIC + ACC_FINAL + ACC_SUPER, className, null, BMH, null);
+ cw.visitSource(sourceFile, null);
+
+ // emit static types and SPECIES_DATA fields
+ cw.visitField(NOT_ACC_PUBLIC + ACC_STATIC, "SPECIES_DATA", SPECIES_DATA_SIG, null, null).visitEnd();
+
+ // emit bound argument fields
+ for (int i = 0; i < types.length(); ++i) {
+ final char t = types.charAt(i);
+ final String fieldName = makeFieldName(types, i);
+ final String fieldDesc = t == 'L' ? JLO_SIG : String.valueOf(t);
+ cw.visitField(ACC_FINAL, fieldName, fieldDesc, null, null).visitEnd();
+ }
+
+ MethodVisitor mv;
+
+ // emit constructor
+ mv = cw.visitMethod(ACC_PRIVATE, "<init>", makeSignature(types, true), null, null);
+ mv.visitCode();
+ mv.visitVarInsn(ALOAD, 0); // this
+ mv.visitVarInsn(ALOAD, 1); // type
+ mv.visitVarInsn(ALOAD, 2); // form
+
+ mv.visitMethodInsn(INVOKESPECIAL, BMH, "<init>", makeSignature("", true), false);
+
+ for (int i = 0, j = 0; i < types.length(); ++i, ++j) {
+ // i counts the arguments, j counts corresponding argument slots
+ char t = types.charAt(i);
+ mv.visitVarInsn(ALOAD, 0);
+ mv.visitVarInsn(typeLoadOp(t), j + 3); // parameters start at 3
+ mv.visitFieldInsn(PUTFIELD, className, makeFieldName(types, i), typeSig(t));
+ if (t == 'J' || t == 'D') {
+ ++j; // adjust argument register access
+ }
+ }
+
+ mv.visitInsn(RETURN);
+ mv.visitMaxs(0, 0);
+ mv.visitEnd();
+
+ // emit implementation of reinvokerTarget()
+ mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "reinvokerTarget", "()" + MH_SIG, null, null);
+ mv.visitCode();
+ mv.visitVarInsn(ALOAD, 0);
+ mv.visitFieldInsn(GETFIELD, className, "argL0", JLO_SIG);
+ mv.visitTypeInsn(CHECKCAST, MH);
+ mv.visitInsn(ARETURN);
+ mv.visitMaxs(0, 0);
+ mv.visitEnd();
+
+ // emit implementation of speciesData()
+ mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "speciesData", MYSPECIES_DATA_SIG, null, null);
+ mv.visitCode();
+ mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);
+ mv.visitInsn(ARETURN);
+ mv.visitMaxs(0, 0);
+ mv.visitEnd();
+
+ // emit implementation of fieldCount()
+ mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "fieldCount", INT_SIG, null, null);
+ mv.visitCode();
+ int fc = types.length();
+ if (fc <= (ICONST_5 - ICONST_0)) {
+ mv.visitInsn(ICONST_0 + fc);
+ } else {
+ mv.visitIntInsn(SIPUSH, fc);
+ }
+ mv.visitInsn(IRETURN);
+ mv.visitMaxs(0, 0);
+ mv.visitEnd();
+ // emit make() ...factory method wrapping constructor
+ mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_STATIC, "make", makeSignature(types, false), null, null);
+ mv.visitCode();
+ // make instance
+ mv.visitTypeInsn(NEW, className);
+ mv.visitInsn(DUP);
+ // load mt, lf
+ mv.visitVarInsn(ALOAD, 0); // type
+ mv.visitVarInsn(ALOAD, 1); // form
+ // load factory method arguments
+ for (int i = 0, j = 0; i < types.length(); ++i, ++j) {
+ // i counts the arguments, j counts corresponding argument slots
+ char t = types.charAt(i);
+ mv.visitVarInsn(typeLoadOp(t), j + 2); // parameters start at 3
+ if (t == 'J' || t == 'D') {
+ ++j; // adjust argument register access
+ }
+ }
+
+ // finally, invoke the constructor and return
+ mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", makeSignature(types, true), false);
+ mv.visitInsn(ARETURN);
+ mv.visitMaxs(0, 0);
+ mv.visitEnd();
+
+ // emit copyWith()
+ mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "copyWith", makeSignature("", false), null, null);
+ mv.visitCode();
+ // make instance
+ mv.visitTypeInsn(NEW, className);
+ mv.visitInsn(DUP);
+ // load mt, lf
+ mv.visitVarInsn(ALOAD, 1);
+ mv.visitVarInsn(ALOAD, 2);
+ // put fields on the stack
+ emitPushFields(types, className, mv);
+ // finally, invoke the constructor and return
+ mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", makeSignature(types, true), false);
+ mv.visitInsn(ARETURN);
+ mv.visitMaxs(0, 0);
+ mv.visitEnd();
+
+ // for each type, emit copyWithExtendT()
+ for (BasicType type : BasicType.ARG_TYPES) {
+ int ord = type.ordinal();
+ char btChar = type.basicTypeChar();
+ mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "copyWithExtend" + btChar, makeSignature(String.valueOf(btChar), false), null, E_THROWABLE);
+ mv.visitCode();
+ // return SPECIES_DATA.extendWith(t).constructor[0].invokeBasic(mt, lf, argL0, ..., narg)
+ // obtain constructor
+ mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);
+ int iconstInsn = ICONST_0 + ord;
+ assert(iconstInsn <= ICONST_5);
+ mv.visitInsn(iconstInsn);
+ mv.visitMethodInsn(INVOKEVIRTUAL, SPECIES_DATA, "extendWith", BMHSPECIES_DATA_EWI_SIG, false);
+ mv.visitFieldInsn(GETFIELD, SPECIES_DATA, "constructor", "[" + MH_SIG);
+ mv.visitInsn(ICONST_0);
+ mv.visitInsn(AALOAD);
+ // load mt, lf
+ mv.visitVarInsn(ALOAD, 1);
+ mv.visitVarInsn(ALOAD, 2);
+ // put fields on the stack
+ emitPushFields(types, className, mv);
+ // put narg on stack
+ mv.visitVarInsn(typeLoadOp(btChar), 3);
+ // finally, invoke the constructor and return
+ mv.visitMethodInsn(INVOKEVIRTUAL, MH, "invokeBasic", makeSignature(types + btChar, false), false);
+ mv.visitInsn(ARETURN);
+ mv.visitMaxs(0, 0);
+ mv.visitEnd();
+ }
+
+ // emit class initializer
+ mv = cw.visitMethod(NOT_ACC_PUBLIC | ACC_STATIC, "<clinit>", VOID_SIG, null, null);
+ mv.visitCode();
+ mv.visitLdcInsn(types);
+ mv.visitLdcInsn(Type.getObjectType(className));
+ mv.visitMethodInsn(INVOKESTATIC, SPECIES_DATA, "getForClass", BMHSPECIES_DATA_GFC_SIG, false);
+ mv.visitFieldInsn(PUTSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);
+ mv.visitInsn(RETURN);
+ mv.visitMaxs(0, 0);
+ mv.visitEnd();
+
+ cw.visitEnd();
+
+ // load class
+ final byte[] classFile = cw.toByteArray();
+ InvokerBytecodeGenerator.maybeDump(className, classFile);
+ Class<? extends BoundMethodHandle> bmhClass =
+ //UNSAFE.defineAnonymousClass(BoundMethodHandle.class, classFile, null).asSubclass(BoundMethodHandle.class);
+ UNSAFE.defineClass(className, classFile, 0, classFile.length,
+ BoundMethodHandle.class.getClassLoader(), null)
+ .asSubclass(BoundMethodHandle.class);
+ UNSAFE.ensureClassInitialized(bmhClass);
+
+ return bmhClass;
+ }
+
+ private static 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 static void emitPushFields(String types, String className, MethodVisitor mv) {
+ for (int i = 0; i < types.length(); ++i) {
+ char tc = types.charAt(i);
+ mv.visitVarInsn(ALOAD, 0);
+ mv.visitFieldInsn(GETFIELD, className, makeFieldName(types, i), typeSig(tc));
+ }
+ }
+
+ static String typeSig(char t) {
+ return t == 'L' ? JLO_SIG : String.valueOf(t);
+ }
+
+ //
+ // Getter MH generation.
+ //
+
+ private static MethodHandle makeGetter(Class<?> cbmhClass, String types, int index) {
+ String fieldName = makeFieldName(types, index);
+ Class<?> fieldType = Wrapper.forBasicType(types.charAt(index)).primitiveType();
+ try {
+ return LOOKUP.findGetter(cbmhClass, fieldName, fieldType);
+ } catch (NoSuchFieldException | IllegalAccessException e) {
+ throw newInternalError(e);
+ }
+ }
+
+ static MethodHandle[] makeGetters(Class<?> cbmhClass, String types, MethodHandle[] mhs) {
+ if (mhs == null) mhs = new MethodHandle[types.length()];
+ for (int i = 0; i < mhs.length; ++i) {
+ mhs[i] = makeGetter(cbmhClass, types, i);
+ assert(mhs[i].internalMemberName().getDeclaringClass() == cbmhClass);
+ }
+ return mhs;
+ }
+
+ static MethodHandle[] makeCtors(Class<? extends BoundMethodHandle> cbmh, String types, MethodHandle mhs[]) {
+ if (mhs == null) mhs = new MethodHandle[1];
+ if (types.equals("")) return mhs; // hack for empty BMH species
+ mhs[0] = makeCbmhCtor(cbmh, types);
+ return mhs;
+ }
+
+ static NamedFunction[] makeNominalGetters(String types, NamedFunction[] nfs, MethodHandle[] getters) {
+ if (nfs == null) nfs = new NamedFunction[types.length()];
+ for (int i = 0; i < nfs.length; ++i) {
+ nfs[i] = new NamedFunction(getters[i]);
+ }
+ return nfs;
+ }
+
+ //
+ // Auxiliary methods.
+ //
+
+ static SpeciesData speciesDataFromConcreteBMHClass(Class<? extends BoundMethodHandle> cbmh) {
+ try {
+ Field F_SPECIES_DATA = cbmh.getDeclaredField("SPECIES_DATA");
+ return (SpeciesData) F_SPECIES_DATA.get(null);
+ } catch (ReflectiveOperationException ex) {
+ throw newInternalError(ex);
+ }
+ }
+
+ /**
+ * Field names in concrete BMHs adhere to this pattern:
+ * arg + type + index
+ * where type is a single character (L, I, J, F, D).
+ */
+ private static String makeFieldName(String types, int index) {
+ assert index >= 0 && index < types.length();
+ return "arg" + types.charAt(index) + index;
+ }
+
+ private static String makeSignature(String types, boolean ctor) {
+ StringBuilder buf = new StringBuilder(SIG_INCIPIT);
+ for (char c : types.toCharArray()) {
+ buf.append(typeSig(c));
+ }
+ return buf.append(')').append(ctor ? "V" : BMH_SIG).toString();
+ }
+
+ static MethodHandle makeCbmhCtor(Class<? extends BoundMethodHandle> cbmh, String types) {
+ try {
+ return LOOKUP.findStatic(cbmh, "make", MethodType.fromMethodDescriptorString(makeSignature(types, false), null));
+ } catch (NoSuchMethodException | IllegalAccessException | IllegalArgumentException | TypeNotPresentException e) {
+ throw newInternalError(e);
+ }
+ }
+ }
+
+ private static final Lookup LOOKUP = Lookup.IMPL_LOOKUP;
+
+ /**
+ * All subclasses must provide such a value describing their type signature.
+ */
+ static final SpeciesData SPECIES_DATA = SpeciesData.EMPTY;
+
+ private static final SpeciesData[] SPECIES_DATA_CACHE = new SpeciesData[5];
+ private static SpeciesData checkCache(int size, String types) {
+ int idx = size - 1;
+ SpeciesData data = SPECIES_DATA_CACHE[idx];
+ if (data != null) return data;
+ SPECIES_DATA_CACHE[idx] = data = getSpeciesData(types);
+ return data;
+ }
+ static SpeciesData speciesData_L() { return checkCache(1, "L"); }
+ static SpeciesData speciesData_LL() { return checkCache(2, "LL"); }
+ static SpeciesData speciesData_LLL() { return checkCache(3, "LLL"); }
+ static SpeciesData speciesData_LLLL() { return checkCache(4, "LLLL"); }
+ static SpeciesData speciesData_LLLLL() { return checkCache(5, "LLLLL"); }
+}