jaroslav@1646: /*
jaroslav@1646:  * Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved.
jaroslav@1646:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
jaroslav@1646:  *
jaroslav@1646:  * This code is free software; you can redistribute it and/or modify it
jaroslav@1646:  * under the terms of the GNU General Public License version 2 only, as
jaroslav@1646:  * published by the Free Software Foundation.  Oracle designates this
jaroslav@1646:  * particular file as subject to the "Classpath" exception as provided
jaroslav@1646:  * by Oracle in the LICENSE file that accompanied this code.
jaroslav@1646:  *
jaroslav@1646:  * This code is distributed in the hope that it will be useful, but WITHOUT
jaroslav@1646:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
jaroslav@1646:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
jaroslav@1646:  * version 2 for more details (a copy is included in the LICENSE file that
jaroslav@1646:  * accompanied this code).
jaroslav@1646:  *
jaroslav@1646:  * You should have received a copy of the GNU General Public License version
jaroslav@1646:  * 2 along with this work; if not, write to the Free Software Foundation,
jaroslav@1646:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
jaroslav@1646:  *
jaroslav@1646:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
jaroslav@1646:  * or visit www.oracle.com if you need additional information or have any
jaroslav@1646:  * questions.
jaroslav@1646:  */
jaroslav@1646: 
jaroslav@1646: package java.lang.invoke;
jaroslav@1646: 
jaroslav@1646: import java.util.Arrays;
jaroslav@1646: import sun.invoke.empty.Empty;
jaroslav@1646: import static java.lang.invoke.MethodHandleStatics.*;
jaroslav@1646: import static java.lang.invoke.MethodHandleNatives.Constants.*;
jaroslav@1646: import static java.lang.invoke.MethodHandles.Lookup.IMPL_LOOKUP;
jaroslav@1646: import static java.lang.invoke.LambdaForm.*;
jaroslav@1646: 
jaroslav@1646: /**
jaroslav@1646:  * Construction and caching of often-used invokers.
jaroslav@1646:  * @author jrose
jaroslav@1646:  */
jaroslav@1646: class Invokers {
jaroslav@1646:     // exact type (sans leading taget MH) for the outgoing call
jaroslav@1646:     private final MethodType targetType;
jaroslav@1646: 
jaroslav@1646:     // FIXME: Get rid of the invokers that are not useful.
jaroslav@1646: 
jaroslav@1646:     // exact invoker for the outgoing call
jaroslav@1646:     private /*lazy*/ MethodHandle exactInvoker;
jaroslav@1646:     private /*lazy*/ MethodHandle basicInvoker;  // invokeBasic (unchecked exact)
jaroslav@1646: 
jaroslav@1646:     // erased (partially untyped but with primitives) invoker for the outgoing call
jaroslav@1646:     // FIXME: get rid of
jaroslav@1646:     private /*lazy*/ MethodHandle erasedInvoker;
jaroslav@1646:     // FIXME: get rid of
jaroslav@1646:     /*lazy*/ MethodHandle erasedInvokerWithDrops;  // for InvokeGeneric
jaroslav@1646: 
jaroslav@1646:     // general invoker for the outgoing call
jaroslav@1646:     private /*lazy*/ MethodHandle generalInvoker;
jaroslav@1646: 
jaroslav@1646:     // general invoker for the outgoing call, uses varargs
jaroslav@1646:     private /*lazy*/ MethodHandle varargsInvoker;
jaroslav@1646: 
jaroslav@1646:     // general invoker for the outgoing call; accepts a trailing Object[]
jaroslav@1646:     private final /*lazy*/ MethodHandle[] spreadInvokers;
jaroslav@1646: 
jaroslav@1646:     // invoker for an unbound callsite
jaroslav@1646:     private /*lazy*/ MethodHandle uninitializedCallSite;
jaroslav@1646: 
jaroslav@1646:     /** Compute and cache information common to all collecting adapters
jaroslav@1646:      *  that implement members of the erasure-family of the given erased type.
jaroslav@1646:      */
jaroslav@1646:     /*non-public*/ Invokers(MethodType targetType) {
jaroslav@1646:         this.targetType = targetType;
jaroslav@1646:         this.spreadInvokers = new MethodHandle[targetType.parameterCount()+1];
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     /*non-public*/ MethodHandle exactInvoker() {
jaroslav@1646:         MethodHandle invoker = exactInvoker;
jaroslav@1646:         if (invoker != null)  return invoker;
jaroslav@1646:         invoker = makeExactOrGeneralInvoker(true);
jaroslav@1646:         exactInvoker = invoker;
jaroslav@1646:         return invoker;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     /*non-public*/ MethodHandle generalInvoker() {
jaroslav@1646:         MethodHandle invoker = generalInvoker;
jaroslav@1646:         if (invoker != null)  return invoker;
jaroslav@1646:         invoker = makeExactOrGeneralInvoker(false);
jaroslav@1646:         generalInvoker = invoker;
jaroslav@1646:         return invoker;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     private MethodHandle makeExactOrGeneralInvoker(boolean isExact) {
jaroslav@1646:         MethodType mtype = targetType;
jaroslav@1646:         MethodType invokerType = mtype.invokerType();
jaroslav@1646:         int which = (isExact ? MethodTypeForm.LF_EX_INVOKER : MethodTypeForm.LF_GEN_INVOKER);
jaroslav@1646:         LambdaForm lform = invokeHandleForm(mtype, false, which);
jaroslav@1646:         MethodHandle invoker = BoundMethodHandle.bindSingle(invokerType, lform, mtype);
jaroslav@1646:         String whichName = (isExact ? "invokeExact" : "invoke");
jaroslav@1646:         invoker = invoker.withInternalMemberName(MemberName.makeMethodHandleInvoke(whichName, mtype));
jaroslav@1646:         assert(checkInvoker(invoker));
jaroslav@1646:         maybeCompileToBytecode(invoker);
jaroslav@1646:         return invoker;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     /** If the target type seems to be common enough, eagerly compile the invoker to bytecodes. */
jaroslav@1646:     private void maybeCompileToBytecode(MethodHandle invoker) {
jaroslav@1646:         final int EAGER_COMPILE_ARITY_LIMIT = 10;
jaroslav@1646:         if (targetType == targetType.erase() &&
jaroslav@1646:             targetType.parameterCount() < EAGER_COMPILE_ARITY_LIMIT) {
jaroslav@1646:             invoker.form.compileToBytecode();
jaroslav@1646:         }
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     /*non-public*/ MethodHandle basicInvoker() {
jaroslav@1646:         MethodHandle invoker = basicInvoker;
jaroslav@1646:         if (invoker != null)  return invoker;
jaroslav@1646:         MethodType basicType = targetType.basicType();
jaroslav@1646:         if (basicType != targetType) {
jaroslav@1646:             // double cache; not used significantly
jaroslav@1646:             return basicInvoker = basicType.invokers().basicInvoker();
jaroslav@1646:         }
jaroslav@1646:         MemberName method = invokeBasicMethod(basicType);
jaroslav@1646:         invoker = DirectMethodHandle.make(method);
jaroslav@1646:         assert(checkInvoker(invoker));
jaroslav@1646:         basicInvoker = invoker;
jaroslav@1646:         return invoker;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     // This next one is called from LambdaForm.NamedFunction.<init>.
jaroslav@1646:     /*non-public*/ static MemberName invokeBasicMethod(MethodType basicType) {
jaroslav@1646:         assert(basicType == basicType.basicType());
jaroslav@1646:         try {
jaroslav@1646:             //Lookup.findVirtual(MethodHandle.class, name, type);
jaroslav@1646:             return IMPL_LOOKUP.resolveOrFail(REF_invokeVirtual, MethodHandle.class, "invokeBasic", basicType);
jaroslav@1646:         } catch (ReflectiveOperationException ex) {
jaroslav@1646:             throw newInternalError("JVM cannot find invoker for "+basicType, ex);
jaroslav@1646:         }
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     private boolean checkInvoker(MethodHandle invoker) {
jaroslav@1646:         assert(targetType.invokerType().equals(invoker.type()))
jaroslav@1646:                 : java.util.Arrays.asList(targetType, targetType.invokerType(), invoker);
jaroslav@1646:         assert(invoker.internalMemberName() == null ||
jaroslav@1646:                invoker.internalMemberName().getMethodType().equals(targetType));
jaroslav@1646:         assert(!invoker.isVarargsCollector());
jaroslav@1646:         return true;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     // FIXME: get rid of
jaroslav@1646:     /*non-public*/ MethodHandle erasedInvoker() {
jaroslav@1646:         MethodHandle xinvoker = exactInvoker();
jaroslav@1646:         MethodHandle invoker = erasedInvoker;
jaroslav@1646:         if (invoker != null)  return invoker;
jaroslav@1646:         MethodType erasedType = targetType.erase();
jaroslav@1646:         invoker = xinvoker.asType(erasedType.invokerType());
jaroslav@1646:         erasedInvoker = invoker;
jaroslav@1646:         return invoker;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     /*non-public*/ MethodHandle spreadInvoker(int leadingArgCount) {
jaroslav@1646:         MethodHandle vaInvoker = spreadInvokers[leadingArgCount];
jaroslav@1646:         if (vaInvoker != null)  return vaInvoker;
jaroslav@1646:         int spreadArgCount = targetType.parameterCount() - leadingArgCount;
jaroslav@1646:         MethodType spreadInvokerType = targetType
jaroslav@1646:             .replaceParameterTypes(leadingArgCount, targetType.parameterCount(), Object[].class);
jaroslav@1646:         if (targetType.parameterSlotCount() <= MethodType.MAX_MH_INVOKER_ARITY) {
jaroslav@1646:             // Factor sinvoker.invoke(mh, a) into ginvoker.asSpreader().invoke(mh, a)
jaroslav@1646:             // where ginvoker.invoke(mh, a*) => mh.invoke(a*).
jaroslav@1646:             MethodHandle genInvoker = generalInvoker();
jaroslav@1646:             vaInvoker = genInvoker.asSpreader(Object[].class, spreadArgCount);
jaroslav@1646:         } else {
jaroslav@1646:             // Cannot build a general invoker here of type ginvoker.invoke(mh, a*[254]).
jaroslav@1646:             // Instead, factor sinvoker.invoke(mh, a) into ainvoker.invoke(filter(mh), a)
jaroslav@1646:             // where filter(mh) == mh.asSpreader(Object[], spreadArgCount)
jaroslav@1646:             MethodHandle arrayInvoker = MethodHandles.exactInvoker(spreadInvokerType);
jaroslav@1646:             MethodHandle makeSpreader;
jaroslav@1646:             try {
jaroslav@1646:                 makeSpreader = IMPL_LOOKUP
jaroslav@1646:                     .findVirtual(MethodHandle.class, "asSpreader",
jaroslav@1646:                         MethodType.methodType(MethodHandle.class, Class.class, int.class));
jaroslav@1646:             } catch (ReflectiveOperationException ex) {
jaroslav@1646:                 throw newInternalError(ex);
jaroslav@1646:             }
jaroslav@1646:             makeSpreader = MethodHandles.insertArguments(makeSpreader, 1, Object[].class, spreadArgCount);
jaroslav@1646:             vaInvoker = MethodHandles.filterArgument(arrayInvoker, 0, makeSpreader);
jaroslav@1646:         }
jaroslav@1646:         assert(vaInvoker.type().equals(spreadInvokerType.invokerType()));
jaroslav@1646:         maybeCompileToBytecode(vaInvoker);
jaroslav@1646:         spreadInvokers[leadingArgCount] = vaInvoker;
jaroslav@1646:         return vaInvoker;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     /*non-public*/ MethodHandle varargsInvoker() {
jaroslav@1646:         MethodHandle vaInvoker = varargsInvoker;
jaroslav@1646:         if (vaInvoker != null)  return vaInvoker;
jaroslav@1646:         vaInvoker = spreadInvoker(0).asType(MethodType.genericMethodType(0, true).invokerType());
jaroslav@1646:         varargsInvoker = vaInvoker;
jaroslav@1646:         return vaInvoker;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     private static MethodHandle THROW_UCS = null;
jaroslav@1646: 
jaroslav@1646:     /*non-public*/ MethodHandle uninitializedCallSite() {
jaroslav@1646:         MethodHandle invoker = uninitializedCallSite;
jaroslav@1646:         if (invoker != null)  return invoker;
jaroslav@1646:         if (targetType.parameterCount() > 0) {
jaroslav@1646:             MethodType type0 = targetType.dropParameterTypes(0, targetType.parameterCount());
jaroslav@1646:             Invokers invokers0 = type0.invokers();
jaroslav@1646:             invoker = MethodHandles.dropArguments(invokers0.uninitializedCallSite(),
jaroslav@1646:                                                   0, targetType.parameterList());
jaroslav@1646:             assert(invoker.type().equals(targetType));
jaroslav@1646:             uninitializedCallSite = invoker;
jaroslav@1646:             return invoker;
jaroslav@1646:         }
jaroslav@1646:         invoker = THROW_UCS;
jaroslav@1646:         if (invoker == null) {
jaroslav@1646:             try {
jaroslav@1646:                 THROW_UCS = invoker = IMPL_LOOKUP
jaroslav@1646:                     .findStatic(CallSite.class, "uninitializedCallSite",
jaroslav@1646:                                 MethodType.methodType(Empty.class));
jaroslav@1646:             } catch (ReflectiveOperationException ex) {
jaroslav@1646:                 throw newInternalError(ex);
jaroslav@1646:             }
jaroslav@1646:         }
jaroslav@1646:         invoker = MethodHandles.explicitCastArguments(invoker, MethodType.methodType(targetType.returnType()));
jaroslav@1646:         invoker = invoker.dropArguments(targetType, 0, targetType.parameterCount());
jaroslav@1646:         assert(invoker.type().equals(targetType));
jaroslav@1646:         uninitializedCallSite = invoker;
jaroslav@1646:         return invoker;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     public String toString() {
jaroslav@1646:         return "Invokers"+targetType;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     static MemberName methodHandleInvokeLinkerMethod(String name,
jaroslav@1646:                                                      MethodType mtype,
jaroslav@1646:                                                      Object[] appendixResult) {
jaroslav@1646:         int which;
jaroslav@1646:         switch (name) {
jaroslav@1646:         case "invokeExact":  which = MethodTypeForm.LF_EX_LINKER; break;
jaroslav@1646:         case "invoke":       which = MethodTypeForm.LF_GEN_LINKER; break;
jaroslav@1646:         default:             throw new InternalError("not invoker: "+name);
jaroslav@1646:         }
jaroslav@1646:         LambdaForm lform;
jaroslav@1646:         if (mtype.parameterSlotCount() <= MethodType.MAX_MH_ARITY - MH_LINKER_ARG_APPENDED) {
jaroslav@1646:             lform = invokeHandleForm(mtype, false, which);
jaroslav@1646:             appendixResult[0] = mtype;
jaroslav@1646:         } else {
jaroslav@1646:             lform = invokeHandleForm(mtype, true, which);
jaroslav@1646:         }
jaroslav@1646:         return lform.vmentry;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     // argument count to account for trailing "appendix value" (typically the mtype)
jaroslav@1646:     private static final int MH_LINKER_ARG_APPENDED = 1;
jaroslav@1646: 
jaroslav@1646:     /** Returns an adapter for invokeExact or generic invoke, as a MH or constant pool linker.
jaroslav@1646:      * If !customized, caller is responsible for supplying, during adapter execution,
jaroslav@1646:      * a copy of the exact mtype.  This is because the adapter might be generalized to
jaroslav@1646:      * a basic type.
jaroslav@1646:      * @param mtype the caller's method type (either basic or full-custom)
jaroslav@1646:      * @param customized whether to use a trailing appendix argument (to carry the mtype)
jaroslav@1646:      * @param which bit-encoded 0x01 whether it is a CP adapter ("linker") or MHs.invoker value ("invoker");
jaroslav@1646:      *                          0x02 whether it is for invokeExact or generic invoke
jaroslav@1646:      */
jaroslav@1646:     private static LambdaForm invokeHandleForm(MethodType mtype, boolean customized, int which) {
jaroslav@1646:         boolean isCached;
jaroslav@1646:         if (!customized) {
jaroslav@1646:             mtype = mtype.basicType();  // normalize Z to I, String to Object, etc.
jaroslav@1646:             isCached = true;
jaroslav@1646:         } else {
jaroslav@1646:             isCached = false;  // maybe cache if mtype == mtype.basicType()
jaroslav@1646:         }
jaroslav@1646:         boolean isLinker, isGeneric;
jaroslav@1646:         String debugName;
jaroslav@1646:         switch (which) {
jaroslav@1646:         case MethodTypeForm.LF_EX_LINKER:   isLinker = true;  isGeneric = false; debugName = "invokeExact_MT"; break;
jaroslav@1646:         case MethodTypeForm.LF_EX_INVOKER:  isLinker = false; isGeneric = false; debugName = "exactInvoker"; break;
jaroslav@1646:         case MethodTypeForm.LF_GEN_LINKER:  isLinker = true;  isGeneric = true;  debugName = "invoke_MT"; break;
jaroslav@1646:         case MethodTypeForm.LF_GEN_INVOKER: isLinker = false; isGeneric = true;  debugName = "invoker"; break;
jaroslav@1646:         default: throw new InternalError();
jaroslav@1646:         }
jaroslav@1646:         LambdaForm lform;
jaroslav@1646:         if (isCached) {
jaroslav@1646:             lform = mtype.form().cachedLambdaForm(which);
jaroslav@1646:             if (lform != null)  return lform;
jaroslav@1646:         }
jaroslav@1646:         // exactInvokerForm (Object,Object)Object
jaroslav@1646:         //   link with java.lang.invoke.MethodHandle.invokeBasic(MethodHandle,Object,Object)Object/invokeSpecial
jaroslav@1646:         final int THIS_MH      = 0;
jaroslav@1646:         final int CALL_MH      = THIS_MH + (isLinker ? 0 : 1);
jaroslav@1646:         final int ARG_BASE     = CALL_MH + 1;
jaroslav@1646:         final int OUTARG_LIMIT = ARG_BASE + mtype.parameterCount();
jaroslav@1646:         final int INARG_LIMIT  = OUTARG_LIMIT + (isLinker && !customized ? 1 : 0);
jaroslav@1646:         int nameCursor = OUTARG_LIMIT;
jaroslav@1646:         final int MTYPE_ARG    = customized ? -1 : nameCursor++;  // might be last in-argument
jaroslav@1646:         final int CHECK_TYPE   = nameCursor++;
jaroslav@1646:         final int LINKER_CALL  = nameCursor++;
jaroslav@1646:         MethodType invokerFormType = mtype.invokerType();
jaroslav@1646:         if (isLinker) {
jaroslav@1646:             if (!customized)
jaroslav@1646:                 invokerFormType = invokerFormType.appendParameterTypes(MemberName.class);
jaroslav@1646:         } else {
jaroslav@1646:             invokerFormType = invokerFormType.invokerType();
jaroslav@1646:         }
jaroslav@1646:         Name[] names = arguments(nameCursor - INARG_LIMIT, invokerFormType);
jaroslav@1646:         assert(names.length == nameCursor)
jaroslav@1646:                 : Arrays.asList(mtype, customized, which, nameCursor, names.length);
jaroslav@1646:         if (MTYPE_ARG >= INARG_LIMIT) {
jaroslav@1646:             assert(names[MTYPE_ARG] == null);
jaroslav@1646:             NamedFunction getter = BoundMethodHandle.getSpeciesData("L").getterFunction(0);
jaroslav@1646:             names[MTYPE_ARG] = new Name(getter, names[THIS_MH]);
jaroslav@1646:             // else if isLinker, then MTYPE is passed in from the caller (e.g., the JVM)
jaroslav@1646:         }
jaroslav@1646: 
jaroslav@1646:         // Make the final call.  If isGeneric, then prepend the result of type checking.
jaroslav@1646:         MethodType outCallType = mtype.basicType();
jaroslav@1646:         Object[] outArgs = Arrays.copyOfRange(names, CALL_MH, OUTARG_LIMIT, Object[].class);
jaroslav@1646:         Object mtypeArg = (customized ? mtype : names[MTYPE_ARG]);
jaroslav@1646:         if (!isGeneric) {
jaroslav@1646:             names[CHECK_TYPE] = new Name(NF_checkExactType, names[CALL_MH], mtypeArg);
jaroslav@1646:             // mh.invokeExact(a*):R => checkExactType(mh, TYPEOF(a*:R)); mh.invokeBasic(a*)
jaroslav@1646:         } else {
jaroslav@1646:             names[CHECK_TYPE] = new Name(NF_checkGenericType, names[CALL_MH], mtypeArg);
jaroslav@1646:             // mh.invokeGeneric(a*):R => checkGenericType(mh, TYPEOF(a*:R)).invokeBasic(a*)
jaroslav@1646:             outArgs[0] = names[CHECK_TYPE];
jaroslav@1646:         }
jaroslav@1646:         names[LINKER_CALL] = new Name(outCallType, outArgs);
jaroslav@1646:         lform = new LambdaForm(debugName, INARG_LIMIT, names);
jaroslav@1646:         if (isLinker)
jaroslav@1646:             lform.compileToBytecode();  // JVM needs a real methodOop
jaroslav@1646:         if (isCached)
jaroslav@1646:             lform = mtype.form().setCachedLambdaForm(which, lform);
jaroslav@1646:         return lform;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     /*non-public*/ static
jaroslav@1646:     WrongMethodTypeException newWrongMethodTypeException(MethodType actual, MethodType expected) {
jaroslav@1646:         // FIXME: merge with JVM logic for throwing WMTE
jaroslav@1646:         return new WrongMethodTypeException("expected "+expected+" but found "+actual);
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     /** Static definition of MethodHandle.invokeExact checking code. */
jaroslav@1646:     /*non-public*/ static
jaroslav@1646:     @ForceInline
jaroslav@1646:     void checkExactType(Object mhObj, Object expectedObj) {
jaroslav@1646:         MethodHandle mh = (MethodHandle) mhObj;
jaroslav@1646:         MethodType expected = (MethodType) expectedObj;
jaroslav@1646:         MethodType actual = mh.type();
jaroslav@1646:         if (actual != expected)
jaroslav@1646:             throw newWrongMethodTypeException(expected, actual);
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     /** Static definition of MethodHandle.invokeGeneric checking code.
jaroslav@1646:      * Directly returns the type-adjusted MH to invoke, as follows:
jaroslav@1646:      * {@code (R)MH.invoke(a*) => MH.asType(TYPEOF(a*:R)).invokeBasic(a*)}
jaroslav@1646:      */
jaroslav@1646:     /*non-public*/ static
jaroslav@1646:     @ForceInline
jaroslav@1646:     Object checkGenericType(Object mhObj, Object expectedObj) {
jaroslav@1646:         MethodHandle mh = (MethodHandle) mhObj;
jaroslav@1646:         MethodType expected = (MethodType) expectedObj;
jaroslav@1646:         if (mh.type() == expected)  return mh;
jaroslav@1646:         MethodHandle atc = mh.asTypeCache;
jaroslav@1646:         if (atc != null && atc.type() == expected)  return atc;
jaroslav@1646:         return mh.asType(expected);
jaroslav@1646:         /* Maybe add more paths here.  Possible optimizations:
jaroslav@1646:          * for (R)MH.invoke(a*),
jaroslav@1646:          * let MT0 = TYPEOF(a*:R), MT1 = MH.type
jaroslav@1646:          *
jaroslav@1646:          * if MT0==MT1 or MT1 can be safely called by MT0
jaroslav@1646:          *  => MH.invokeBasic(a*)
jaroslav@1646:          * if MT1 can be safely called by MT0[R := Object]
jaroslav@1646:          *  => MH.invokeBasic(a*) & checkcast(R)
jaroslav@1646:          * if MT1 can be safely called by MT0[* := Object]
jaroslav@1646:          *  => checkcast(A)* & MH.invokeBasic(a*) & checkcast(R)
jaroslav@1646:          * if a big adapter BA can be pulled out of (MT0,MT1)
jaroslav@1646:          *  => BA.invokeBasic(MT0,MH,a*)
jaroslav@1646:          * if a local adapter LA can cached on static CS0 = new GICS(MT0)
jaroslav@1646:          *  => CS0.LA.invokeBasic(MH,a*)
jaroslav@1646:          * else
jaroslav@1646:          *  => MH.asType(MT0).invokeBasic(A*)
jaroslav@1646:          */
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     static MemberName linkToCallSiteMethod(MethodType mtype) {
jaroslav@1646:         LambdaForm lform = callSiteForm(mtype, false);
jaroslav@1646:         return lform.vmentry;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     static MemberName linkToTargetMethod(MethodType mtype) {
jaroslav@1646:         LambdaForm lform = callSiteForm(mtype, true);
jaroslav@1646:         return lform.vmentry;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     // skipCallSite is true if we are optimizing a ConstantCallSite
jaroslav@1646:     private static LambdaForm callSiteForm(MethodType mtype, boolean skipCallSite) {
jaroslav@1646:         mtype = mtype.basicType();  // normalize Z to I, String to Object, etc.
jaroslav@1646:         final int which = (skipCallSite ? MethodTypeForm.LF_MH_LINKER : MethodTypeForm.LF_CS_LINKER);
jaroslav@1646:         LambdaForm lform = mtype.form().cachedLambdaForm(which);
jaroslav@1646:         if (lform != null)  return lform;
jaroslav@1646:         // exactInvokerForm (Object,Object)Object
jaroslav@1646:         //   link with java.lang.invoke.MethodHandle.invokeBasic(MethodHandle,Object,Object)Object/invokeSpecial
jaroslav@1646:         final int ARG_BASE     = 0;
jaroslav@1646:         final int OUTARG_LIMIT = ARG_BASE + mtype.parameterCount();
jaroslav@1646:         final int INARG_LIMIT  = OUTARG_LIMIT + 1;
jaroslav@1646:         int nameCursor = OUTARG_LIMIT;
jaroslav@1646:         final int APPENDIX_ARG = nameCursor++;  // the last in-argument
jaroslav@1646:         final int CSITE_ARG    = skipCallSite ? -1 : APPENDIX_ARG;
jaroslav@1646:         final int CALL_MH      = skipCallSite ? APPENDIX_ARG : nameCursor++;  // result of getTarget
jaroslav@1646:         final int LINKER_CALL  = nameCursor++;
jaroslav@1646:         MethodType invokerFormType = mtype.appendParameterTypes(skipCallSite ? MethodHandle.class : CallSite.class);
jaroslav@1646:         Name[] names = arguments(nameCursor - INARG_LIMIT, invokerFormType);
jaroslav@1646:         assert(names.length == nameCursor);
jaroslav@1646:         assert(names[APPENDIX_ARG] != null);
jaroslav@1646:         if (!skipCallSite)
jaroslav@1646:             names[CALL_MH] = new Name(NF_getCallSiteTarget, names[CSITE_ARG]);
jaroslav@1646:         // (site.)invokedynamic(a*):R => mh = site.getTarget(); mh.invokeBasic(a*)
jaroslav@1646:         final int PREPEND_MH = 0, PREPEND_COUNT = 1;
jaroslav@1646:         Object[] outArgs = Arrays.copyOfRange(names, ARG_BASE, OUTARG_LIMIT + PREPEND_COUNT, Object[].class);
jaroslav@1646:         // prepend MH argument:
jaroslav@1646:         System.arraycopy(outArgs, 0, outArgs, PREPEND_COUNT, outArgs.length - PREPEND_COUNT);
jaroslav@1646:         outArgs[PREPEND_MH] = names[CALL_MH];
jaroslav@1646:         names[LINKER_CALL] = new Name(mtype, outArgs);
jaroslav@1646:         lform = new LambdaForm((skipCallSite ? "linkToTargetMethod" : "linkToCallSite"), INARG_LIMIT, names);
jaroslav@1646:         lform.compileToBytecode();  // JVM needs a real methodOop
jaroslav@1646:         lform = mtype.form().setCachedLambdaForm(which, lform);
jaroslav@1646:         return lform;
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     /** Static definition of MethodHandle.invokeGeneric checking code. */
jaroslav@1646:     /*non-public*/ static
jaroslav@1646:     @ForceInline
jaroslav@1646:     Object getCallSiteTarget(Object site) {
jaroslav@1646:         return ((CallSite)site).getTarget();
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646:     // Local constant functions:
jaroslav@1646:     private static final NamedFunction NF_checkExactType;
jaroslav@1646:     private static final NamedFunction NF_checkGenericType;
jaroslav@1646:     private static final NamedFunction NF_asType;
jaroslav@1646:     private static final NamedFunction NF_getCallSiteTarget;
jaroslav@1646:     static {
jaroslav@1646:         try {
jaroslav@1646:             NF_checkExactType = new NamedFunction(Invokers.class
jaroslav@1646:                     .getDeclaredMethod("checkExactType", Object.class, Object.class));
jaroslav@1646:             NF_checkGenericType = new NamedFunction(Invokers.class
jaroslav@1646:                     .getDeclaredMethod("checkGenericType", Object.class, Object.class));
jaroslav@1646:             NF_asType = new NamedFunction(MethodHandle.class
jaroslav@1646:                     .getDeclaredMethod("asType", MethodType.class));
jaroslav@1646:             NF_getCallSiteTarget = new NamedFunction(Invokers.class
jaroslav@1646:                     .getDeclaredMethod("getCallSiteTarget", Object.class));
jaroslav@1646:             NF_checkExactType.resolve();
jaroslav@1646:             NF_checkGenericType.resolve();
jaroslav@1646:             NF_getCallSiteTarget.resolve();
jaroslav@1646:             // bound
jaroslav@1646:         } catch (ReflectiveOperationException ex) {
jaroslav@1646:             throw newInternalError(ex);
jaroslav@1646:         }
jaroslav@1646:     }
jaroslav@1646: 
jaroslav@1646: }