001    /*
002     * Copyright 2010-2013 JetBrains s.r.o.
003     *
004     * Licensed under the Apache License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     * http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    
017    package org.jetbrains.jet.codegen;
018    
019    import com.google.common.collect.Lists;
020    import com.intellij.psi.PsiElement;
021    import com.intellij.util.ArrayUtil;
022    import org.jetbrains.annotations.NotNull;
023    import org.jetbrains.annotations.Nullable;
024    import org.jetbrains.asm4.MethodVisitor;
025    import org.jetbrains.asm4.Type;
026    import org.jetbrains.asm4.commons.InstructionAdapter;
027    import org.jetbrains.asm4.commons.Method;
028    import org.jetbrains.jet.codegen.binding.CalculatedClosure;
029    import org.jetbrains.jet.codegen.context.CodegenContext;
030    import org.jetbrains.jet.codegen.context.LocalLookup;
031    import org.jetbrains.jet.codegen.signature.BothSignatureWriter;
032    import org.jetbrains.jet.codegen.signature.JvmMethodSignature;
033    import org.jetbrains.jet.codegen.state.GenerationState;
034    import org.jetbrains.jet.codegen.state.JetTypeMapper;
035    import org.jetbrains.jet.lang.descriptors.*;
036    import org.jetbrains.jet.lang.resolve.BindingContext;
037    import org.jetbrains.jet.lang.resolve.java.JvmAbi;
038    import org.jetbrains.jet.lang.resolve.java.sam.SingleAbstractMethodUtils;
039    import org.jetbrains.jet.lang.resolve.name.Name;
040    import org.jetbrains.jet.lang.types.JetType;
041    import org.jetbrains.jet.lang.types.lang.KotlinBuiltIns;
042    
043    import java.util.Collection;
044    import java.util.Collections;
045    import java.util.List;
046    
047    import static org.jetbrains.asm4.Opcodes.*;
048    import static org.jetbrains.jet.codegen.AsmUtil.*;
049    import static org.jetbrains.jet.codegen.CodegenUtil.isConst;
050    import static org.jetbrains.jet.codegen.binding.CodegenBinding.*;
051    
052    public class ClosureCodegen extends ParentCodegenAwareImpl {
053        private final PsiElement fun;
054        private final FunctionDescriptor funDescriptor;
055        private final ClassDescriptor samInterface;
056        private final Type superClass;
057        private final CodegenContext context;
058        private final FunctionGenerationStrategy strategy;
059        private final CalculatedClosure closure;
060        private final Type asmType;
061    
062        private Method constructor;
063    
064        public ClosureCodegen(
065                @NotNull GenerationState state,
066                @NotNull PsiElement fun,
067                @NotNull FunctionDescriptor funDescriptor,
068                @Nullable ClassDescriptor samInterface,
069                @NotNull Type closureSuperClass,
070                @NotNull CodegenContext context,
071                @NotNull LocalLookup localLookup,
072                @NotNull FunctionGenerationStrategy strategy,
073                @Nullable MemberCodegen parentCodegen
074        ) {
075            super(state, parentCodegen);
076    
077            this.fun = fun;
078            this.funDescriptor = funDescriptor;
079            this.samInterface = samInterface;
080            this.superClass = closureSuperClass;
081            this.context = context.intoClosure(funDescriptor, localLookup, typeMapper);
082            this.strategy = strategy;
083    
084            ClassDescriptor classDescriptor = anonymousClassForFunction(bindingContext, funDescriptor);
085            this.closure = bindingContext.get(CLOSURE, classDescriptor);
086            assert closure != null : "Closure must be calculated for class: " + classDescriptor;
087    
088            this.asmType = asmTypeForAnonymousClass(bindingContext, funDescriptor);
089        }
090    
091        public void gen() {
092            ClassBuilder cv = state.getFactory().newVisitor(asmType, fun.getContainingFile());
093    
094            FunctionDescriptor interfaceFunction;
095            String[] superInterfaces;
096    
097            if (samInterface == null) {
098                interfaceFunction = getInvokeFunction(funDescriptor);
099                superInterfaces = ArrayUtil.EMPTY_STRING_ARRAY;
100            }
101            else {
102                interfaceFunction = SingleAbstractMethodUtils.getAbstractMethodOfSamInterface(samInterface);
103                superInterfaces = new String[] { typeMapper.mapType(samInterface).getInternalName() };
104            }
105    
106            cv.defineClass(fun,
107                           V1_6,
108                           ACC_FINAL | ACC_SUPER,
109                           asmType.getInternalName(),
110                           getGenericSignature(),
111                           superClass.getInternalName(),
112                           superInterfaces
113            );
114            cv.visitSource(fun.getContainingFile().getName(), null);
115    
116    
117            generateBridge(interfaceFunction, cv);
118    
119            JvmMethodSignature jvmMethodSignature = typeMapper.mapSignature(interfaceFunction.getName(), funDescriptor);
120    
121            FunctionCodegen fc = new FunctionCodegen(context, cv, state, getParentCodegen());
122            fc.generateMethod(fun, jvmMethodSignature, funDescriptor, strategy);
123    
124            this.constructor = generateConstructor(cv);
125    
126            if (isConst(closure)) {
127                generateConstInstance(cv);
128            }
129    
130            genClosureFields(closure, cv, typeMapper);
131    
132            fc.generateDefaultIfNeeded(context.intoFunction(funDescriptor),
133                                       typeMapper.mapSignature(Name.identifier("invoke"), funDescriptor),
134                                       funDescriptor,
135                                       context.getContextKind(),
136                                       DefaultParameterValueLoader.DEFAULT);
137    
138            cv.done();
139        }
140    
141        @NotNull
142        public StackValue putInstanceOnStack(@NotNull InstructionAdapter v, @NotNull ExpressionCodegen codegen) {
143            if (isConst(closure)) {
144                v.getstatic(asmType.getInternalName(), JvmAbi.INSTANCE_FIELD, asmType.getDescriptor());
145            }
146            else {
147                v.anew(asmType);
148                v.dup();
149    
150                codegen.pushClosureOnStack(closure, false);
151                v.invokespecial(asmType.getInternalName(), "<init>", constructor.getDescriptor());
152            }
153            return StackValue.onStack(asmType);
154        }
155    
156    
157        private void generateConstInstance(@NotNull ClassBuilder cv) {
158            MethodVisitor mv = cv.newMethod(fun, ACC_STATIC | ACC_SYNTHETIC, "<clinit>", "()V", null, ArrayUtil.EMPTY_STRING_ARRAY);
159            InstructionAdapter iv = new InstructionAdapter(mv);
160    
161            cv.newField(fun, ACC_STATIC | ACC_FINAL, JvmAbi.INSTANCE_FIELD, asmType.getDescriptor(), null, null);
162    
163            if (state.getClassBuilderMode() == ClassBuilderMode.FULL) {
164                mv.visitCode();
165                genInitSingletonField(asmType, iv);
166                mv.visitInsn(RETURN);
167                FunctionCodegen.endVisit(mv, "<clinit>", fun);
168            }
169        }
170    
171        private void generateBridge(@NotNull FunctionDescriptor interfaceFunction, @NotNull ClassBuilder cv) {
172            Method bridge = typeMapper.mapSignature(interfaceFunction).getAsmMethod();
173    
174            Method delegate = typeMapper.mapSignature(interfaceFunction.getName(), funDescriptor).getAsmMethod();
175    
176            if (bridge.getDescriptor().equals(delegate.getDescriptor())) {
177                return;
178            }
179    
180            MethodVisitor mv = cv.newMethod(fun, ACC_PUBLIC | ACC_BRIDGE, interfaceFunction.getName().asString(),
181                                            bridge.getDescriptor(), null, ArrayUtil.EMPTY_STRING_ARRAY);
182            if (state.getClassBuilderMode() == ClassBuilderMode.FULL) {
183                mv.visitCode();
184    
185                InstructionAdapter iv = new InstructionAdapter(mv);
186    
187                iv.load(0, asmType);
188    
189                ReceiverParameterDescriptor receiver = funDescriptor.getReceiverParameter();
190                int count = 1;
191                if (receiver != null) {
192                    StackValue.local(count, bridge.getArgumentTypes()[count - 1]).put(typeMapper.mapType(receiver.getType()), iv);
193                    count++;
194                }
195    
196                List<ValueParameterDescriptor> params = funDescriptor.getValueParameters();
197                for (ValueParameterDescriptor param : params) {
198                    StackValue.local(count, bridge.getArgumentTypes()[count - 1]).put(typeMapper.mapType(param.getType()), iv);
199                    count++;
200                }
201    
202                iv.invokevirtual(asmType.getInternalName(), interfaceFunction.getName().asString(), delegate.getDescriptor());
203                StackValue.onStack(delegate.getReturnType()).put(bridge.getReturnType(), iv);
204    
205                iv.areturn(bridge.getReturnType());
206    
207                FunctionCodegen.endVisit(mv, "bridge", fun);
208            }
209        }
210    
211        @NotNull
212        private Method generateConstructor(@NotNull ClassBuilder cv) {
213            List<FieldInfo> args = calculateConstructorParameters(typeMapper, closure, asmType);
214    
215            Type[] argTypes = fieldListToTypeArray(args);
216    
217            Method constructor = new Method("<init>", Type.VOID_TYPE, argTypes);
218            MethodVisitor mv = cv.newMethod(fun, NO_FLAG_PACKAGE_PRIVATE, "<init>", constructor.getDescriptor(), null,
219                                            ArrayUtil.EMPTY_STRING_ARRAY);
220            if (state.getClassBuilderMode() == ClassBuilderMode.FULL) {
221                mv.visitCode();
222                InstructionAdapter iv = new InstructionAdapter(mv);
223    
224                iv.load(0, superClass);
225                iv.invokespecial(superClass.getInternalName(), "<init>", "()V");
226    
227                int k = 1;
228                for (FieldInfo fieldInfo : args) {
229                    k = AsmUtil.genAssignInstanceFieldFromParam(fieldInfo, k, iv);
230                }
231    
232                iv.visitInsn(RETURN);
233    
234                FunctionCodegen.endVisit(iv, "constructor", fun);
235            }
236            return constructor;
237        }
238    
239        @NotNull
240        public static List<FieldInfo> calculateConstructorParameters(
241                @NotNull JetTypeMapper typeMapper,
242                @NotNull CalculatedClosure closure,
243                @NotNull Type ownerType
244        ) {
245            BindingContext bindingContext = typeMapper.getBindingContext();
246            List<FieldInfo> args = Lists.newArrayList();
247            ClassDescriptor captureThis = closure.getCaptureThis();
248            if (captureThis != null) {
249                Type type = typeMapper.mapType(captureThis);
250                args.add(FieldInfo.createForHiddenField(ownerType, type, CAPTURED_THIS_FIELD));
251            }
252            ClassifierDescriptor captureReceiver = closure.getCaptureReceiver();
253            if (captureReceiver != null) {
254                args.add(FieldInfo.createForHiddenField(ownerType, typeMapper.mapType(captureReceiver), CAPTURED_RECEIVER_FIELD));
255            }
256    
257            for (DeclarationDescriptor descriptor : closure.getCaptureVariables().keySet()) {
258                if (descriptor instanceof VariableDescriptor && !(descriptor instanceof PropertyDescriptor)) {
259                    Type sharedVarType = typeMapper.getSharedVarType(descriptor);
260    
261                    Type type = sharedVarType != null
262                                      ? sharedVarType
263                                      : typeMapper.mapType((VariableDescriptor) descriptor);
264                    args.add(FieldInfo.createForHiddenField(ownerType, type, "$" + descriptor.getName().asString()));
265                }
266                else if (isLocalNamedFun(descriptor)) {
267                    Type classType = asmTypeForAnonymousClass(bindingContext, (FunctionDescriptor) descriptor);
268                    args.add(FieldInfo.createForHiddenField(ownerType, classType, "$" + descriptor.getName().asString()));
269                }
270                else if (descriptor instanceof FunctionDescriptor) {
271                    assert captureReceiver != null;
272                }
273            }
274            return args;
275        }
276    
277        private static Type[] fieldListToTypeArray(List<FieldInfo> args) {
278            Type[] argTypes = new Type[args.size()];
279            for (int i = 0; i != argTypes.length; ++i) {
280                argTypes[i] = args.get(i).getFieldType();
281            }
282            return argTypes;
283        }
284    
285        @NotNull
286        private String getGenericSignature() {
287            ClassDescriptor classDescriptor = anonymousClassForFunction(bindingContext, funDescriptor);
288            Collection<JetType> supertypes = classDescriptor.getTypeConstructor().getSupertypes();
289            assert supertypes.size() == 1 : "Closure must have exactly one supertype: " + funDescriptor;
290            JetType supertype = supertypes.iterator().next();
291    
292            BothSignatureWriter sw = new BothSignatureWriter(BothSignatureWriter.Mode.CLASS, true);
293            typeMapper.writeFormalTypeParameters(Collections.<TypeParameterDescriptor>emptyList(), sw);
294            sw.writeSuperclass();
295            typeMapper.mapSupertype(supertype, sw);
296            sw.writeSuperclassEnd();
297    
298            String signature = sw.makeJavaGenericSignature();
299            assert signature != null : "Closure superclass must have a generic signature: " + funDescriptor;
300            return signature;
301        }
302    
303        private static FunctionDescriptor getInvokeFunction(FunctionDescriptor funDescriptor) {
304            int paramCount = funDescriptor.getValueParameters().size();
305            KotlinBuiltIns builtIns = KotlinBuiltIns.getInstance();
306            ClassDescriptor funClass = funDescriptor.getReceiverParameter() == null
307                                       ? builtIns.getFunction(paramCount)
308                                       : builtIns.getExtensionFunction(paramCount);
309            return funClass.getDefaultType().getMemberScope().getFunctions(Name.identifier("invoke")).iterator().next();
310        }
311    }