34 import sun.invoke.util.Wrapper;

    30 

    35 

    31 import java.util.ArrayList;

    36 import java.lang.invoke.LambdaForm.NamedFunction;

    32 import java.util.List;

    37 import java.lang.invoke.MethodHandles.Lookup;

    38 import java.lang.reflect.Field;

    39 import java.util.concurrent.ConcurrentHashMap;

    40 import java.util.concurrent.ConcurrentMap;

    41 import java.util.function.Function;

    45 import static java.lang.invoke.MethodHandleStatics.*;

    36 import static java.lang.invoke.LambdaForm.BasicType.V_TYPE_NUM;

    46 import static jdk.internal.org.objectweb.asm.Opcodes.*;

    37 import static java.lang.invoke.LambdaForm.BasicType.V_TYPE_NUM;

    38 import static java.lang.invoke.LambdaForm.BasicType.V_TYPE_NUM;

    39 import static java.lang.invoke.MethodHandles.Lookup.IMPL_LOOKUP;

    40 import static java.lang.invoke.MethodHandleNatives.Constants.*;

    41 import static java.lang.invoke.MethodHandleStatics.newInternalError;

    42 import static java.lang.invoke.MethodHandleStatics.uncaughtException;

    59         assert(speciesData() == speciesData(form));

    55         assert(speciesData() == speciesDataFor(form));

    73                 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(I_TYPE).constructor().invokeBasic(type, form, ValueConversions.widenSubword(x));

    69                 return (BoundMethodHandle) SPECIALIZER.topSpecies().extendWith(I_TYPE_NUM).factory().invokeBasic(type, form, ValueConversions.widenSubword(x));

    75                 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(J_TYPE).constructor().invokeBasic(type, form, (long) x);

    71                 return (BoundMethodHandle) SPECIALIZER.topSpecies().extendWith(J_TYPE_NUM).factory().invokeBasic(type, form, (long) x);

    77                 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(F_TYPE).constructor().invokeBasic(type, form, (float) x);

    73                 return (BoundMethodHandle) SPECIALIZER.topSpecies().extendWith(F_TYPE_NUM).factory().invokeBasic(type, form, (float) x);

    79                 return (BoundMethodHandle) SpeciesData.EMPTY.extendWith(D_TYPE).constructor().invokeBasic(type, form, (double) x);

    75                 return (BoundMethodHandle) SPECIALIZER.topSpecies().extendWith(D_TYPE_NUM).factory().invokeBasic(type, form, (double) x);

   140                 Species_L.SPECIES_DATA, Species_L.SPECIES_DATA.getterFunction(0));

   136                 Species_L.BMH_SPECIES, Species_L.BMH_SPECIES.getterFunction(0));

   145      * Return the {@link SpeciesData} instance representing this BMH species. All subclasses must provide a

   141      * Return the {@link BoundMethodHandle.SpeciesData} instance representing this BMH species. All subclasses must provide a

   148     /*non-public*/ abstract SpeciesData speciesData();

   144     /*non-public*/ abstract BoundMethodHandle.SpeciesData speciesData();

   149 

   145 

   150     /*non-public*/ static SpeciesData speciesData(LambdaForm form) {

   146     /*non-public*/ static BoundMethodHandle.SpeciesData speciesDataFor(LambdaForm form) {

   152         if (c instanceof SpeciesData)

   148         if (c instanceof SpeciesData) {

   155         return SpeciesData.EMPTY;

   152         return SPECIALIZER.topSpecies();

   161     /*non-public*/ abstract int fieldCount();

   158     /*non-public*/ final int fieldCount() { return speciesData().fieldCount(); }

   170         int count = speciesData().fieldCount();

   167         int count = fieldCount();

   183             switch (speciesData().fieldType(i)) {

   180             Class<?> fieldType = speciesData().fieldTypes().get(i);

   184             case L_TYPE: return          speciesData().getters[i].invokeBasic(this);

   181             switch (BasicType.basicType(fieldType)) {

   185             case I_TYPE: return (int)    speciesData().getters[i].invokeBasic(this);

   182                 case L_TYPE: return          speciesData().getter(i).invokeBasic(this);

   186             case J_TYPE: return (long)   speciesData().getters[i].invokeBasic(this);

   183                 case I_TYPE: return (int)    speciesData().getter(i).invokeBasic(this);

   187             case F_TYPE: return (float)  speciesData().getters[i].invokeBasic(this);

   184                 case J_TYPE: return (long)   speciesData().getter(i).invokeBasic(this);

   188             case D_TYPE: return (double) speciesData().getters[i].invokeBasic(this);

   185                 case F_TYPE: return (float)  speciesData().getter(i).invokeBasic(this);

   186                 case D_TYPE: return (double) speciesData().getter(i).invokeBasic(this);

   193         throw new InternalError("unexpected type: " + speciesData().typeChars+"."+i);

   191         throw new InternalError("unexpected type: " + speciesData().key()+"."+i);

   220             return SPECIES_DATA;

   221             return BMH_SPECIES;

   221         }

   222         }

   222         @Override

   223 

   223         /*non-public*/ int fieldCount() {

   224         /*non-public*/ static @Stable SpeciesData BMH_SPECIES;

   224             return 1;

   225 

   225         }

   226         /*non-public*/ static final SpeciesData SPECIES_DATA = new SpeciesData("L", Species_L.class);

   237                 return (BoundMethodHandle) SPECIES_DATA.extendWith(L_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);

   236                 return (BoundMethodHandle) BMH_SPECIES.extendWith(L_TYPE_NUM).factory().invokeBasic(mt, lf, argL0, narg);

   245                 return (BoundMethodHandle) SPECIES_DATA.extendWith(I_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);

   244                 return (BoundMethodHandle) BMH_SPECIES.extendWith(I_TYPE_NUM).factory().invokeBasic(mt, lf, argL0, narg);

   253                 return (BoundMethodHandle) SPECIES_DATA.extendWith(J_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);

   252                 return (BoundMethodHandle) BMH_SPECIES.extendWith(J_TYPE_NUM).factory().invokeBasic(mt, lf, argL0, narg);

   261                 return (BoundMethodHandle) SPECIES_DATA.extendWith(F_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);

   260                 return (BoundMethodHandle) BMH_SPECIES.extendWith(F_TYPE_NUM).factory().invokeBasic(mt, lf, argL0, narg);

   269                 return (BoundMethodHandle) SPECIES_DATA.extendWith(D_TYPE).constructor().invokeBasic(mt, lf, argL0, narg);

   268                 return (BoundMethodHandle) BMH_SPECIES.extendWith(D_TYPE_NUM).factory().invokeBasic(mt, lf, argL0, narg);

   280     /**

   279     /*non-public*/

   281      * Meta-data wrapper for concrete BMH types.

   280     static final class SpeciesData extends ClassSpecializer<BoundMethodHandle, String, SpeciesData>.SpeciesData {

   282      * Each BMH type corresponds to a given sequence of basic field types (LIJFD).

   281         // This array is filled in lazily, as new species come into being over time.

   283      * The fields are immutable; their values are fully specified at object construction.

   282         @Stable final private SpeciesData[] extensions = new SpeciesData[ARG_TYPE_LIMIT];

   284      * Each BMH type supplies an array of getter functions which may be used in lambda forms.

   283 

   285      * A BMH is constructed by cloning a shorter BMH and adding one or more new field values.

   284         public SpeciesData(Specializer outer, String key) {

   286      * The shortest possible BMH has zero fields; its class is SimpleMethodHandle.

   285             outer.super(key);

   287      * BMH species are not interrelated by subtyping, even though it would appear that

   286         }

   288      * a shorter BMH could serve as a supertype of a longer one which extends it.

   287 

   289      */

   288         @Override

   290     static class SpeciesData {

   289         protected String deriveClassName() {

   291         private final String                             typeChars;

   290             String typeString = deriveTypeString();

   292         private final BasicType[]                        typeCodes;

   291             if (typeString.isEmpty()) {

   293         private final Class<? extends BoundMethodHandle> clazz;

   292                 return SimpleMethodHandle.class.getName();

   294         // Bootstrapping requires circular relations MH -> BMH -> SpeciesData -> MH

   293             }

   295         // Therefore, we need a non-final link in the chain.  Use array elements.

   294             return BoundMethodHandle.class.getName() + "$Species_" + typeString;

   296         @Stable private final MethodHandle[]             constructor;

   295         }

   297         @Stable private final MethodHandle[]             getters;

   296 

   298         @Stable private final NamedFunction[]            nominalGetters;

   297         @Override

   299         @Stable private final SpeciesData[]              extensions;

   298         protected List<Class<?>> deriveFieldTypes(String key) {

   300 

   299             ArrayList<Class<?>> types = new ArrayList<>(key.length());

   301         /*non-public*/ int fieldCount() {

   300             for (int i = 0; i < key.length(); i++) {

   302             return typeCodes.length;

   301                 types.add(basicType(key.charAt(i)).basicTypeClass());

   303         }

   302             }

   304         /*non-public*/ BasicType fieldType(int i) {

   303             return types;

   305             return typeCodes[i];

   304         }

   306         }

   305 

   307         /*non-public*/ char fieldTypeChar(int i) {

   306         @Override

   308             return typeChars.charAt(i);

   307         protected String deriveTypeString() {

   309         }

   308             // (If/when we have to add nominal types, just inherit the more complex default.)

   310         String fieldSignature() {

   309             return key();

   311             return typeChars;

   310         }

   312         }

   311 

   313         public Class<? extends BoundMethodHandle> fieldHolder() {

   312         @Override

   314             return clazz;

   313         protected MethodHandle deriveTransformHelper(MemberName transform, int whichtm) {

   315         }

   314             if (whichtm == Specializer.TN_COPY_NO_EXTEND) {

   316         public String toString() {

   315                 return factory();

   317             return "SpeciesData<"+fieldSignature()+">";

   316             } else if (whichtm < ARG_TYPE_LIMIT) {

   317                 return extendWith((byte) whichtm).factory();

   318             } else {

   319                 throw newInternalError("bad transform");

   320             }

   321         }

   322 

   323         @Override

   324         protected <X> List<X> deriveTransformHelperArguments(MemberName transform, int whichtm, List<X> args, List<X> fields) {

   325             assert(verifyTHAargs(transform, whichtm, args, fields));

   326             // The rule is really simple:  Keep the first two arguments

   327             // the same, then put in the fields, then put any other argument.

   328             args.addAll(2, fields);

   329             return args;

   330         }

   331 

   332         private boolean verifyTHAargs(MemberName transform, int whichtm, List<?> args, List<?> fields) {

   333             assert(transform == Specializer.BMH_TRANSFORMS.get(whichtm));

   334             assert(args.size() == transform.getMethodType().parameterCount());

   335             assert(fields.size() == this.fieldCount());

   336             final int MH_AND_LF = 2;

   337             if (whichtm == Specializer.TN_COPY_NO_EXTEND) {

   338                 assert(transform.getMethodType().parameterCount() == MH_AND_LF);

   339             } else if (whichtm < ARG_TYPE_LIMIT) {

   340                 assert(transform.getMethodType().parameterCount() == MH_AND_LF+1);

   341                 final BasicType type = basicType((byte) whichtm);

   342                 assert(transform.getParameterTypes()[MH_AND_LF] == type.basicTypeClass());

   343             } else {

   344                 return false;

   345             }

   346             return true;

   347         }

   348 

   349         /*non-public*/ SpeciesData extendWith(byte typeNum) {

   350             SpeciesData sd = extensions[typeNum];

   351             if (sd != null)  return sd;

   352             sd = SPECIALIZER.findSpecies(key() + BasicType.basicType(typeNum).basicTypeChar());

   353             extensions[typeNum] = sd;

   354             return sd;

   355         }

   356     }

   357 

   358     /*non-public*/

   359     static final Specializer SPECIALIZER = new Specializer();

   360     static {

   361         SimpleMethodHandle.BMH_SPECIES = BoundMethodHandle.SPECIALIZER.findSpecies("");

   362         Species_L.BMH_SPECIES = BoundMethodHandle.SPECIALIZER.findSpecies("L");

   363     }

   364 

   365     /*non-public*/

   366     static final class Specializer extends ClassSpecializer<BoundMethodHandle, String, SpeciesData> {

   367 

   368         private static final MemberName SPECIES_DATA_ACCESSOR;

   369 

   370         static {

   371             try {

   372                 SPECIES_DATA_ACCESSOR = IMPL_LOOKUP.resolveOrFail(REF_invokeVirtual, BoundMethodHandle.class,

   373                         "speciesData", MethodType.methodType(BoundMethodHandle.SpeciesData.class));

   374             } catch (ReflectiveOperationException ex) {

   375                 throw newInternalError("Bootstrap link error", ex);

   376             }

   377         }

   378 

   379         private Specializer() {

   380             super(  // Reified type parameters:

   381                     BoundMethodHandle.class, String.class, BoundMethodHandle.SpeciesData.class,

   382                     // Principal constructor type:

   383                     MethodType.methodType(void.class, MethodType.class, LambdaForm.class),

   384                     // Required linkage between class and species:

   385                     SPECIES_DATA_ACCESSOR,

   386                     "BMH_SPECIES",

   387                     BMH_TRANSFORMS);

   388         }

   389 

   390         @Override

   391         protected String topSpeciesKey() {

   392             return "";

   393         }

   394 

   395         @Override

   396         protected BoundMethodHandle.SpeciesData newSpeciesData(String key) {

   397             return new BoundMethodHandle.SpeciesData(this, key);

   398         }

   399 

   400         static final List<MemberName> BMH_TRANSFORMS;

   401         static final int TN_COPY_NO_EXTEND = V_TYPE_NUM;

   402         static {

   403             final Class<BoundMethodHandle> BMH = BoundMethodHandle.class;

   404             // copyWithExtendLIJFD + copyWith

   405             try {

   406                 BMH_TRANSFORMS = List.of(

   407                         IMPL_LOOKUP.resolveOrFail(REF_invokeVirtual, BMH, "copyWithExtendL", MethodType.methodType(BMH, MethodType.class, LambdaForm.class, Object.class)),

   408                         IMPL_LOOKUP.resolveOrFail(REF_invokeVirtual, BMH, "copyWithExtendI", MethodType.methodType(BMH, MethodType.class, LambdaForm.class, int.class)),

   409                         IMPL_LOOKUP.resolveOrFail(REF_invokeVirtual, BMH, "copyWithExtendJ", MethodType.methodType(BMH, MethodType.class, LambdaForm.class, long.class)),

   410                         IMPL_LOOKUP.resolveOrFail(REF_invokeVirtual, BMH, "copyWithExtendF", MethodType.methodType(BMH, MethodType.class, LambdaForm.class, float.class)),

   411                         IMPL_LOOKUP.resolveOrFail(REF_invokeVirtual, BMH, "copyWithExtendD", MethodType.methodType(BMH, MethodType.class, LambdaForm.class, double.class)),

   412                         IMPL_LOOKUP.resolveOrFail(REF_invokeVirtual, BMH, "copyWith", MethodType.methodType(BMH, MethodType.class, LambdaForm.class))

   413                 );

   414             } catch (ReflectiveOperationException ex) {

   415                 throw newInternalError("Failed resolving copyWith methods", ex);

   416             }

   417 

   418             // as it happens, there is one transform per BasicType including V_TYPE

   419             assert(BMH_TRANSFORMS.size() == TYPE_LIMIT);

   321          * Return a {@link LambdaForm.Name} containing a {@link LambdaForm.NamedFunction} that

   423          * Generation of concrete BMH classes.

   322          * represents a MH bound to a generic invoker, which in turn forwards to the corresponding

   424          *

   323          * getter.

   425          * A concrete BMH species is fit for binding a number of values adhering to a

   426          * given type pattern. Reference types are erased.

   427          *

   428          * BMH species are cached by type pattern.

   429          *

   430          * A BMH species has a number of fields with the concrete (possibly erased) types of

   431          * bound values. Setters are provided as an API in BMH. Getters are exposed as MHs,

   432          * which can be included as names in lambda forms.

   325         NamedFunction getterFunction(int i) {

   434         class Factory extends ClassSpecializer<BoundMethodHandle, String, BoundMethodHandle.SpeciesData>.Factory {

   326             NamedFunction nf = nominalGetters[i];

   435             @Override

   327             assert(nf.memberDeclaringClassOrNull() == fieldHolder());

   436             protected String chooseFieldName(Class<?> type, int index) {

   328             assert(nf.returnType() == fieldType(i));

   437                 return "arg" + super.chooseFieldName(type, index);

   329             return nf;

   438             }

   330         }

   439         }

   331 

   440 

   332         NamedFunction[] getterFunctions() {

   441         @Override

   333             return nominalGetters;

   442         protected Factory makeFactory() {

   334         }

   443             return new Factory();

   335 

   444         }

   336         MethodHandle[] getterHandles() { return getters; }

   445       }

   337 

   446 

   338         MethodHandle constructor() {

   447     static SpeciesData speciesData_L()      { return Species_L.BMH_SPECIES; }

   339             return constructor[0];

   448     static SpeciesData speciesData_LL()     { return SPECIALIZER.findSpecies("LL"); }

   340         }

   449     static SpeciesData speciesData_LLL()    { return SPECIALIZER.findSpecies("LLL"); }

   341 

   450     static SpeciesData speciesData_LLLL()   { return SPECIALIZER.findSpecies("LLLL"); }

   342         static final SpeciesData EMPTY = new SpeciesData("", BoundMethodHandle.class);

   451     static SpeciesData speciesData_LLLLL()  { return SPECIALIZER.findSpecies("LLLLL"); }

   343 

   344         SpeciesData(String types, Class<? extends BoundMethodHandle> clazz) {

   345             this.typeChars = types;

   346             this.typeCodes = basicTypes(types);

   347             this.clazz = clazz;

   348             if (!INIT_DONE) {

   349                 this.constructor = new MethodHandle[1];  // only one ctor

   350                 this.getters = new MethodHandle[types.length()];

   351                 this.nominalGetters = new NamedFunction[types.length()];

   352             } else {

   353                 this.constructor = Factory.makeCtors(clazz, types, null);

   354                 this.getters = Factory.makeGetters(clazz, types, null);

   355                 this.nominalGetters = Factory.makeNominalGetters(types, null, this.getters);

   356             }

   357             this.extensions = new SpeciesData[ARG_TYPE_LIMIT];

   358         }

   359 

   360         private void initForBootstrap() {

   361             assert(!INIT_DONE);

   362             if (constructor() == null) {

   363                 String types = typeChars;

   364                 CACHE.put(types, this);

   365                 Factory.makeCtors(clazz, types, this.constructor);

   366                 Factory.makeGetters(clazz, types, this.getters);

   367                 Factory.makeNominalGetters(types, this.nominalGetters, this.getters);

   368             }

   369         }

   370 

   371         private static final ConcurrentMap<String, SpeciesData> CACHE = new ConcurrentHashMap<>();

   372         private static final boolean INIT_DONE;  // set after <clinit> finishes...

   373 

   374         SpeciesData extendWith(byte type) {

   375             return extendWith(BasicType.basicType(type));

   376         }

   377 

   378         SpeciesData extendWith(BasicType type) {

   379             int ord = type.ordinal();

   380             SpeciesData d = extensions[ord];

   381             if (d != null)  return d;

   382             extensions[ord] = d = get(typeChars+type.basicTypeChar());

   383             return d;

   384         }

   385 

   386         private static SpeciesData get(String types) {

   387             return CACHE.computeIfAbsent(types, new Function<String, SpeciesData>() {

   388                 @Override

   389                 public SpeciesData apply(String types) {

   390                     Class<? extends BoundMethodHandle> bmhcl = Factory.getConcreteBMHClass(types);

   391                     // SpeciesData instantiation may throw VirtualMachineError because of

   392                     // code cache overflow...

   393                     SpeciesData speciesData = new SpeciesData(types, bmhcl);

   394                     // CHM.computeIfAbsent ensures only one SpeciesData will be set

   395                     // successfully on the concrete BMH class if ever

   396                     Factory.setSpeciesDataToConcreteBMHClass(bmhcl, speciesData);

   397                     // the concrete BMH class is published via SpeciesData instance

   398                     // returned here only after it's SPECIES_DATA field is set

   399                     return speciesData;

   400                 }

   401             });

   402         }

   403 

   404         /**

   405          * This is to be called when assertions are enabled. It checks whether SpeciesData for all of the statically

   406          * defined species subclasses of BoundMethodHandle has been added to the SpeciesData cache. See below in the

   407          * static initializer for

   408          */

   409         static boolean speciesDataCachePopulated() {

   410             Class<BoundMethodHandle> rootCls = BoundMethodHandle.class;

   411             for (Class<?> c : rootCls.getDeclaredClasses()) {

   412                 if (rootCls.isAssignableFrom(c)) {

   413                     final Class<? extends BoundMethodHandle> cbmh = c.asSubclass(BoundMethodHandle.class);

   414                     SpeciesData d = Factory.getSpeciesDataFromConcreteBMHClass(cbmh);

   415                     assert(d != null) : cbmh.getName();

   416                     assert(d.clazz == cbmh);

   417                     assert(CACHE.get(d.typeChars) == d);

   418                 }

   419             }

   420             return true;

   421         }

   422 

   423         static {

   424             // Pre-fill the BMH species-data cache with EMPTY and all BMH's inner subclasses.

   425             EMPTY.initForBootstrap();

   426             Species_L.SPECIES_DATA.initForBootstrap();

   427             // check that all static SpeciesData instances have been initialized

   428             assert speciesDataCachePopulated();

   429             // Note:  Do not simplify this, because INIT_DONE must not be

   430             // a compile-time constant during bootstrapping.

   431             INIT_DONE = Boolean.TRUE;

   432         }

   433     }

   434 

   435     static SpeciesData getSpeciesData(String types) {

   436         return SpeciesData.get(types);

   437     }

   438 

   439     /**

   440      * Generation of concrete BMH classes.

   441      *

   442      * A concrete BMH species is fit for binding a number of values adhering to a

   443      * given type pattern. Reference types are erased.

   444      *

   445      * BMH species are cached by type pattern.

   446      *

   447      * A BMH species has a number of fields with the concrete (possibly erased) types of

   448      * bound values. Setters are provided as an API in BMH. Getters are exposed as MHs,

   449      * which can be included as names in lambda forms.

   450      */

   451     static class Factory {

   452 

   453         private static final String JLO_SIG  = "Ljava/lang/Object;";

   454         private static final String MH       = "java/lang/invoke/MethodHandle";

   455         private static final String MH_SIG   = "L"+MH+";";

   456         private static final String BMH      = "java/lang/invoke/BoundMethodHandle";

   457         private static final String BMH_NAME = "java.lang.invoke.BoundMethodHandle";

   458         private static final String BMH_SIG  = "L"+BMH+";";

   459         private static final String SPECIES_DATA     = "java/lang/invoke/BoundMethodHandle$SpeciesData";

   460         private static final String SPECIES_DATA_SIG = "L"+SPECIES_DATA+";";

   461         private static final String STABLE_SIG       = "Ljdk/internal/vm/annotation/Stable;";

   462 

   463         private static final String SPECIES_PREFIX_NAME = "Species_";

   464         private static final String SPECIES_PREFIX_PATH = BMH + "$" + SPECIES_PREFIX_NAME;

   465         private static final String SPECIES_CLASS_PREFIX = BMH_NAME + "$" + SPECIES_PREFIX_NAME;

   466 

   467         private static final String BMHSPECIES_DATA_EWI_SIG = "(B)" + SPECIES_DATA_SIG;

   468         private static final String MYSPECIES_DATA_SIG = "()" + SPECIES_DATA_SIG;

   469         private static final String INT_SIG    = "()I";

   470 

   471         private static final String SIG_INCIPIT = "(Ljava/lang/invoke/MethodType;Ljava/lang/invoke/LambdaForm;";

   472 

   473         private static final String[] E_THROWABLE = new String[] { "java/lang/Throwable" };

   474 

   475         private static final ConcurrentMap<String, Class<? extends BoundMethodHandle>> CLASS_CACHE = new ConcurrentHashMap<>();

   476 

   477         /**

   478          * Get a concrete subclass of BMH for a given combination of bound types.

   479          *

   480          * @param types the type signature, wherein reference types are erased to 'L'

   481          * @return the concrete BMH class

   482          */

   483         static Class<? extends BoundMethodHandle> getConcreteBMHClass(String types) {

   484             // CHM.computeIfAbsent ensures generateConcreteBMHClass is called

   485             // only once per key.

   486             return CLASS_CACHE.computeIfAbsent(

   487                 types, new Function<String, Class<? extends BoundMethodHandle>>() {

   488                     @Override

   489                     public Class<? extends BoundMethodHandle> apply(String types) {

   490                         String shortTypes = LambdaForm.shortenSignature(types);

   491                         String className = SPECIES_CLASS_PREFIX + shortTypes;

   492                         Class<?> c = BootLoader.loadClassOrNull(className);

   493                         if (TRACE_RESOLVE) {

   494                             System.out.println("[BMH_RESOLVE] " + shortTypes +

   495                                     (c != null ? " (success)" : " (fail)") );

   496                         }

   497                         if (c != null) {

   498                             return c.asSubclass(BoundMethodHandle.class);

   499                         } else {

   500                             // Not pregenerated, generate the class

   501                             return generateConcreteBMHClass(shortTypes, types);

   502                         }

   503                     }

   504                 });

   505         }

   506 

   507         /**

   508          * Generate a concrete subclass of BMH for a given combination of bound types.

   509          *

   510          * A concrete BMH species adheres to the following schema:

   511          *

   512          * <pre>

   513          * class Species_[[types]] extends BoundMethodHandle {

   514          *     [[fields]]

   515          *     final SpeciesData speciesData() { return SpeciesData.get("[[types]]"); }

   516          * }

   517          * </pre>

   518          *

   519          * The {@code [[types]]} signature is precisely the string that is passed to this

   520          * method.

   521          *

   522          * The {@code [[fields]]} section consists of one field definition per character in

   523          * the type signature, adhering to the naming schema described in the definition of

   524          * {@link #makeFieldName}.

   525          *

   526          * For example, a concrete BMH species for two reference and one integral bound values

   527          * would have the following shape:

   528          *

   529          * <pre>

   530          * class BoundMethodHandle { ... private static

   531          * final class Species_LLI extends BoundMethodHandle {

   532          *     final Object argL0;

   533          *     final Object argL1;

   534          *     final int argI2;

   535          *     private Species_LLI(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) {

   536          *         super(mt, lf);

   537          *         this.argL0 = argL0;

   538          *         this.argL1 = argL1;

   539          *         this.argI2 = argI2;

   540          *     }

   541          *     final SpeciesData speciesData() { return SPECIES_DATA; }

   542          *     final int fieldCount() { return 3; }

   543          *     @Stable static SpeciesData SPECIES_DATA; // injected afterwards

   544          *     static BoundMethodHandle make(MethodType mt, LambdaForm lf, Object argL0, Object argL1, int argI2) {

   545          *         return new Species_LLI(mt, lf, argL0, argL1, argI2);

   546          *     }

   547          *     final BoundMethodHandle copyWith(MethodType mt, LambdaForm lf) {

   548          *         return new Species_LLI(mt, lf, argL0, argL1, argI2);

   549          *     }

   550          *     final BoundMethodHandle copyWithExtendL(MethodType mt, LambdaForm lf, Object narg) {

   551          *         return SPECIES_DATA.extendWith(L_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);

   552          *     }

   553          *     final BoundMethodHandle copyWithExtendI(MethodType mt, LambdaForm lf, int narg) {

   554          *         return SPECIES_DATA.extendWith(I_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);

   555          *     }

   556          *     final BoundMethodHandle copyWithExtendJ(MethodType mt, LambdaForm lf, long narg) {

   557          *         return SPECIES_DATA.extendWith(J_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);

   558          *     }

   559          *     final BoundMethodHandle copyWithExtendF(MethodType mt, LambdaForm lf, float narg) {

   560          *         return SPECIES_DATA.extendWith(F_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);

   561          *     }

   562          *     public final BoundMethodHandle copyWithExtendD(MethodType mt, LambdaForm lf, double narg) {

   563          *         return SPECIES_DATA.extendWith(D_TYPE).constructor().invokeBasic(mt, lf, argL0, argL1, argI2, narg);

   564          *     }

   565          * }

   566          * </pre>

   567          *

   568          * @param types the type signature, wherein reference types are erased to 'L'

   569          * @return the generated concrete BMH class

   570          */

   571         static Class<? extends BoundMethodHandle> generateConcreteBMHClass(String shortTypes,

   572                 String types) {

   573             final String className  = speciesInternalClassName(shortTypes);

   574             byte[] classFile = generateConcreteBMHClassBytes(shortTypes, types, className);

   575 

   576             // load class

   577             InvokerBytecodeGenerator.maybeDump(className, classFile);

   578             Class<? extends BoundMethodHandle> bmhClass =

   579                 UNSAFE.defineClass(className, classFile, 0, classFile.length,

   580                                    BoundMethodHandle.class.getClassLoader(), null)

   581                     .asSubclass(BoundMethodHandle.class);

   582 

   583             return bmhClass;

   584         }

   585 

   586         static String speciesInternalClassName(String shortTypes) {

   587             return SPECIES_PREFIX_PATH + shortTypes;

   588         }

   589 

   590         static byte[] generateConcreteBMHClassBytes(final String shortTypes,

   591                 final String types, final String className) {

   592             final String sourceFile = SPECIES_PREFIX_NAME + shortTypes;

   593 

   594             final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_MAXS + ClassWriter.COMPUTE_FRAMES);

   595             final int NOT_ACC_PUBLIC = 0;  // not ACC_PUBLIC

   596             cw.visit(V1_6, NOT_ACC_PUBLIC + ACC_FINAL + ACC_SUPER, className, null, BMH, null);

   597             cw.visitSource(sourceFile, null);

   598 

   599             // emit static types and SPECIES_DATA fields

   600             FieldVisitor fw = cw.visitField(NOT_ACC_PUBLIC + ACC_STATIC, "SPECIES_DATA", SPECIES_DATA_SIG, null, null);

   601             fw.visitAnnotation(STABLE_SIG, true);

   602             fw.visitEnd();

   603 

   604             // emit bound argument fields

   605             for (int i = 0; i < types.length(); ++i) {

   606                 final char t = types.charAt(i);

   607                 final String fieldName = makeFieldName(types, i);

   608                 final String fieldDesc = t == 'L' ? JLO_SIG : String.valueOf(t);

   609                 cw.visitField(ACC_FINAL, fieldName, fieldDesc, null, null).visitEnd();

   610             }

   611 

   612             MethodVisitor mv;

   613 

   614             // emit constructor

   615             mv = cw.visitMethod(ACC_PRIVATE, "<init>", makeSignature(types, true), null, null);

   616             mv.visitCode();

   617             mv.visitVarInsn(ALOAD, 0); // this

   618             mv.visitVarInsn(ALOAD, 1); // type

   619             mv.visitVarInsn(ALOAD, 2); // form

   620 

   621             mv.visitMethodInsn(INVOKESPECIAL, BMH, "<init>", makeSignature("", true), false);

   622 

   623             for (int i = 0, j = 0; i < types.length(); ++i, ++j) {

   624                 // i counts the arguments, j counts corresponding argument slots

   625                 char t = types.charAt(i);

   626                 mv.visitVarInsn(ALOAD, 0);

   627                 mv.visitVarInsn(typeLoadOp(t), j + 3); // parameters start at 3

   628                 mv.visitFieldInsn(PUTFIELD, className, makeFieldName(types, i), typeSig(t));

   629                 if (t == 'J' || t == 'D') {

   630                     ++j; // adjust argument register access

   631                 }

   632             }

   633 

   634             mv.visitInsn(RETURN);

   635             mv.visitMaxs(0, 0);

   636             mv.visitEnd();

   637 

   638             // emit implementation of speciesData()

   639             mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "speciesData", MYSPECIES_DATA_SIG, null, null);

   640             mv.visitCode();

   641             mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);

   642             mv.visitInsn(ARETURN);

   643             mv.visitMaxs(0, 0);

   644             mv.visitEnd();

   645 

   646             // emit implementation of fieldCount()

   647             mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "fieldCount", INT_SIG, null, null);

   648             mv.visitCode();

   649             int fc = types.length();

   650             if (fc <= (ICONST_5 - ICONST_0)) {

   651                 mv.visitInsn(ICONST_0 + fc);

   652             } else {

   653                 mv.visitIntInsn(SIPUSH, fc);

   654             }

   655             mv.visitInsn(IRETURN);

   656             mv.visitMaxs(0, 0);

   657             mv.visitEnd();

   658             // emit make()  ...factory method wrapping constructor

   659             mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_STATIC, "make", makeSignature(types, false), null, null);

   660             mv.visitCode();

   661             // make instance

   662             mv.visitTypeInsn(NEW, className);

   663             mv.visitInsn(DUP);

   664             // load mt, lf

   665             mv.visitVarInsn(ALOAD, 0);  // type

   666             mv.visitVarInsn(ALOAD, 1);  // form

   667             // load factory method arguments

   668             for (int i = 0, j = 0; i < types.length(); ++i, ++j) {

   669                 // i counts the arguments, j counts corresponding argument slots

   670                 char t = types.charAt(i);

   671                 mv.visitVarInsn(typeLoadOp(t), j + 2); // parameters start at 3

   672                 if (t == 'J' || t == 'D') {

   673                     ++j; // adjust argument register access

   674                 }

   675             }

   676 

   677             // finally, invoke the constructor and return

   678             mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", makeSignature(types, true), false);

   679             mv.visitInsn(ARETURN);

   680             mv.visitMaxs(0, 0);

   681             mv.visitEnd();

   682 

   683             // emit copyWith()

   684             mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "copyWith", makeSignature("", false), null, null);

   685             mv.visitCode();

   686             // make instance

   687             mv.visitTypeInsn(NEW, className);

   688             mv.visitInsn(DUP);

   689             // load mt, lf

   690             mv.visitVarInsn(ALOAD, 1);

   691             mv.visitVarInsn(ALOAD, 2);

   692             // put fields on the stack

   693             emitPushFields(types, className, mv);

   694             // finally, invoke the constructor and return

   695             mv.visitMethodInsn(INVOKESPECIAL, className, "<init>", makeSignature(types, true), false);

   696             mv.visitInsn(ARETURN);

   697             mv.visitMaxs(0, 0);

   698             mv.visitEnd();

   699 

   700             // for each type, emit copyWithExtendT()

   701             for (BasicType type : BasicType.ARG_TYPES) {

   702                 int ord = type.ordinal();

   703                 char btChar = type.basicTypeChar();

   704                 mv = cw.visitMethod(NOT_ACC_PUBLIC + ACC_FINAL, "copyWithExtend" + btChar, makeSignature(String.valueOf(btChar), false), null, E_THROWABLE);

   705                 mv.visitCode();

   706                 // return SPECIES_DATA.extendWith(t).constructor().invokeBasic(mt, lf, argL0, ..., narg)

   707                 // obtain constructor

   708                 mv.visitFieldInsn(GETSTATIC, className, "SPECIES_DATA", SPECIES_DATA_SIG);

   709                 int iconstInsn = ICONST_0 + ord;

   710                 assert(iconstInsn <= ICONST_5);

   711                 mv.visitInsn(iconstInsn);

   712                 mv.visitMethodInsn(INVOKEVIRTUAL, SPECIES_DATA, "extendWith", BMHSPECIES_DATA_EWI_SIG, false);

   713                 mv.visitMethodInsn(INVOKEVIRTUAL, SPECIES_DATA, "constructor", "()" + MH_SIG, false);

   714                 // load mt, lf

   715                 mv.visitVarInsn(ALOAD, 1);

   716                 mv.visitVarInsn(ALOAD, 2);

   717                 // put fields on the stack

   718                 emitPushFields(types, className, mv);

   719                 // put narg on stack

   720                 mv.visitVarInsn(typeLoadOp(btChar), 3);

   721                 // finally, invoke the constructor and return

   722                 mv.visitMethodInsn(INVOKEVIRTUAL, MH, "invokeBasic", makeSignature(types + btChar, false), false);

   723                 mv.visitInsn(ARETURN);

   724                 mv.visitMaxs(0, 0);

   725                 mv.visitEnd();

   726             }

   727 

   728             cw.visitEnd();

   729 

   730             return cw.toByteArray();

   731         }

   732 

   733         private static int typeLoadOp(char t) {

   734             switch (t) {

   735             case 'L': return ALOAD;

   736             case 'I': return ILOAD;

   737             case 'J': return LLOAD;

   738             case 'F': return FLOAD;

   739             case 'D': return DLOAD;

   740             default : throw newInternalError("unrecognized type " + t);

   741             }

   742         }

   743 

   744         private static void emitPushFields(String types, String className, MethodVisitor mv) {

   745             for (int i = 0; i < types.length(); ++i) {

   746                 char tc = types.charAt(i);

   747                 mv.visitVarInsn(ALOAD, 0);

   748                 mv.visitFieldInsn(GETFIELD, className, makeFieldName(types, i), typeSig(tc));

   749             }

   750         }

   751 

   752         static String typeSig(char t) {

   753             return t == 'L' ? JLO_SIG : String.valueOf(t);

   754         }

   755 

   756         //

   757         // Getter MH generation.

   758         //

   759 

   760         private static MethodHandle makeGetter(Class<?> cbmhClass, String types, int index) {

   761             String fieldName = makeFieldName(types, index);

   762             Class<?> fieldType = Wrapper.forBasicType(types.charAt(index)).primitiveType();

   763             try {

   764                 return LOOKUP.findGetter(cbmhClass, fieldName, fieldType);

   765             } catch (NoSuchFieldException | IllegalAccessException e) {

   766                 throw newInternalError(e);

   767             }

   768         }

   769 

   770         static MethodHandle[] makeGetters(Class<?> cbmhClass, String types, MethodHandle[] mhs) {

   771             if (mhs == null)  mhs = new MethodHandle[types.length()];

   772             for (int i = 0; i < mhs.length; ++i) {

   773                 mhs[i] = makeGetter(cbmhClass, types, i);

   774                 assert(mhs[i].internalMemberName().getDeclaringClass() == cbmhClass);

   775             }

   776             return mhs;

   777         }

   778 

   779         static MethodHandle[] makeCtors(Class<? extends BoundMethodHandle> cbmh, String types, MethodHandle mhs[]) {

   780             if (mhs == null)  mhs = new MethodHandle[1];

   781             if (types.equals(""))  return mhs;  // hack for empty BMH species

   782             mhs[0] = makeCbmhCtor(cbmh, types);

   783             return mhs;

   784         }

   785 

   786         static NamedFunction[] makeNominalGetters(String types, NamedFunction[] nfs, MethodHandle[] getters) {

   787             if (nfs == null)  nfs = new NamedFunction[types.length()];

   788             for (int i = 0; i < nfs.length; ++i) {

   789                 nfs[i] = new NamedFunction(getters[i]);

   790             }

   791             return nfs;

   792         }

   793 

   794         //

   795         // Auxiliary methods.

   796         //

   797 

   798         static SpeciesData getSpeciesDataFromConcreteBMHClass(Class<? extends BoundMethodHandle> cbmh) {

   799             try {

   800                 Field F_SPECIES_DATA = cbmh.getDeclaredField("SPECIES_DATA");

   801                 return (SpeciesData) F_SPECIES_DATA.get(null);

   802             } catch (ReflectiveOperationException ex) {

   803                 throw newInternalError(ex);

   804             }

   805         }

   806 

   807         static void setSpeciesDataToConcreteBMHClass(Class<? extends BoundMethodHandle> cbmh, SpeciesData speciesData) {

   808             try {

   809                 Field F_SPECIES_DATA = cbmh.getDeclaredField("SPECIES_DATA");

   810                 // ## FIXME: annotation parser can't create proxy classes until module system is fully initialzed

   811                 // assert F_SPECIES_DATA.getDeclaredAnnotation(Stable.class) != null;

   812                 F_SPECIES_DATA.set(null, speciesData);

   813             } catch (ReflectiveOperationException ex) {

   814                 throw newInternalError(ex);

   815             }

   816         }

   817 

   818         /**

   819          * Field names in concrete BMHs adhere to this pattern:

   820          * arg + type + index

   821          * where type is a single character (L, I, J, F, D).

   822          */

   823         private static String makeFieldName(String types, int index) {

   824             assert index >= 0 && index < types.length();

   825             return "arg" + types.charAt(index) + index;

   826         }

   827 

   828         private static String makeSignature(String types, boolean ctor) {

   829             StringBuilder buf = new StringBuilder(SIG_INCIPIT);

   830             int len = types.length();

   831             for (int i = 0; i < len; i++) {

   832                 buf.append(typeSig(types.charAt(i)));

   833             }

   834             return buf.append(')').append(ctor ? "V" : BMH_SIG).toString();

   835         }

   836 

   837         private static MethodType makeConstructorType(String types) {

   838             int length = types.length();

   839             Class<?> ptypes[] = new Class<?>[length + 2];

   840             ptypes[0] = MethodType.class;

   841             ptypes[1] = LambdaForm.class;

   842             for (int i = 0; i < length; i++) {

   843                 ptypes[i + 2] = BasicType.basicType(types.charAt(i)).basicTypeClass();

   844             }

   845             return MethodType.makeImpl(BoundMethodHandle.class, ptypes, true);

   846         }

   847 

   848         static MethodHandle makeCbmhCtor(Class<? extends BoundMethodHandle> cbmh, String types) {

   849             try {

   850                 return LOOKUP.findStatic(cbmh, "make", makeConstructorType(types));

   851             } catch (NoSuchMethodException | IllegalAccessException | IllegalArgumentException | TypeNotPresentException e) {

   852                 throw newInternalError(e);

   853             }

   854         }

   855     }

   856 

   857     static final Lookup LOOKUP = Lookup.IMPL_LOOKUP;

   858 

   859     /**

   860      * All subclasses must provide such a value describing their type signature.

   861      */

   862     static final SpeciesData SPECIES_DATA = SpeciesData.EMPTY;

   863 

   864     private static final SpeciesData[] SPECIES_DATA_CACHE = new SpeciesData[6];

   865     private static SpeciesData checkCache(int size, String types) {

   866         int idx = size - 1;

   867         SpeciesData data = SPECIES_DATA_CACHE[idx];

   868         if (data != null)  return data;

   869         SPECIES_DATA_CACHE[idx] = data = getSpeciesData(types);

   870         return data;

   871     }

   872     static SpeciesData speciesData_L()      { return checkCache(1, "L"); }

   873     static SpeciesData speciesData_LL()     { return checkCache(2, "LL"); }

   874     static SpeciesData speciesData_LLL()    { return checkCache(3, "LLL"); }

   875     static SpeciesData speciesData_LLLL()   { return checkCache(4, "LLLL"); }

   876     static SpeciesData speciesData_LLLLL()  { return checkCache(5, "LLLLL"); }