Example usage for org.objectweb.asm Label Label

List of usage examples for org.objectweb.asm Label Label

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Introduction

In this page you can find the example usage for org.objectweb.asm Label Label.

Prototype

public Label()

Source Link

Document

Constructs a new label.

Usage

From source file:dijkstra.gen.DijkstraCodeGenerator.java

License:Open Source License

/**
 * Get the values of the left and right children on the stack and then perform
 * the operation./*from  www.  jav  a 2  s .  c om*/
 * @see dijkstra.ast.ASTVisitor#visit(dijkstra.ast.ASTNodeFactory.BinaryExpressionNode)
 */
public byte[] visit(BinaryExpressionNode binary) {
    final MethodVisitor mv = mvStack.peek();
    DijkstraType childOneType = binary.getExpr1().getType();
    if (childOneType == DijkstraType.ARRAY) {
        childOneType = ((ArraySymbol) ((ArrayAccessorNode) binary.getExpr1()).getId().symbol).getArrayType();
    }
    DijkstraType childTwoType = binary.getExpr2().getType();
    if (childTwoType == DijkstraType.ARRAY) {
        childTwoType = ((ArraySymbol) ((ArrayAccessorNode) binary.getExpr2()).getId().symbol).getArrayType();
    }
    Label lab1, lab2;
    if (binary.getOp() == DijkstraParser.AMP) {
        lab1 = new Label();
        lab2 = new Label();
        binary.getExpr1().accept(this);
        mv.visitJumpInsn(IFEQ, lab1);
        binary.getExpr2().accept(this);
        mv.visitJumpInsn(IFEQ, lab1);
        mv.visitInsn(ICONST_1);
        mv.visitJumpInsn(GOTO, lab2);
        mv.visitLabel(lab1);
        mv.visitInsn(ICONST_0);
        mv.visitLabel(lab2);
    } else if (binary.getOp() == DijkstraParser.PIPE) {
        lab1 = new Label();
        lab2 = new Label();
        binary.getExpr1().accept(this);
        mv.visitJumpInsn(IFNE, lab1);
        binary.getExpr2().accept(this);
        mv.visitJumpInsn(IFNE, lab1);
        mv.visitInsn(ICONST_0);
        mv.visitJumpInsn(GOTO, lab2);
        mv.visitLabel(lab1);
        mv.visitInsn(ICONST_1);
        mv.visitLabel(lab2);
    } else {
        binary.getExpr1().accept(this);
        if ((childOneType == DijkstraType.INT && childTwoType == DijkstraType.FLOAT)
                || (binary.getOp() == DijkstraParser.SLASH && childOneType == DijkstraType.INT)) {
            mv.visitInsn(L2D);
        }
        binary.getExpr2().accept(this);
        if ((childOneType == DijkstraType.FLOAT && childTwoType == DijkstraType.INT)
                || (binary.getOp() == DijkstraParser.SLASH && childTwoType == DijkstraType.INT)) {
            mv.visitInsn(L2D);
        }
        switch (binary.getOp()) {
        case DijkstraParser.LT:
            lab1 = new Label();
            lab2 = new Label();
            if (childOneType == DijkstraType.INT && childTwoType == DijkstraType.INT) {
                mv.visitInsn(LCMP);
            } else {
                mv.visitInsn(DCMPL);
            }
            mv.visitJumpInsn(IFGE, lab1);
            mv.visitInsn(ICONST_1); // left < right
            mv.visitJumpInsn(GOTO, lab2);
            mv.visitLabel(lab1);
            mv.visitInsn(ICONST_0); // right >= left
            mv.visitLabel(lab2);
            break;
        case DijkstraParser.LTEQ:
            lab1 = new Label();
            lab2 = new Label();
            if (childOneType == DijkstraType.INT && childTwoType == DijkstraType.INT) {
                mv.visitInsn(LCMP);
            } else {
                mv.visitInsn(DCMPL);
            }
            mv.visitJumpInsn(IFGT, lab1);
            mv.visitInsn(ICONST_1); // left <= right
            mv.visitJumpInsn(GOTO, lab2);
            mv.visitLabel(lab1);
            mv.visitInsn(ICONST_0); // right > left
            mv.visitLabel(lab2);
            break;
        case DijkstraParser.GT:
            lab1 = new Label();
            lab2 = new Label();
            if (childOneType == DijkstraType.INT && childTwoType == DijkstraType.INT) {
                mv.visitInsn(LCMP);
            } else {
                mv.visitInsn(DCMPL);
            }
            mv.visitJumpInsn(IFLE, lab1);
            mv.visitInsn(ICONST_1); // left > right
            mv.visitJumpInsn(GOTO, lab2);
            mv.visitLabel(lab1);
            mv.visitInsn(ICONST_0); // right <= left
            mv.visitLabel(lab2);
            break;
        case DijkstraParser.GTEQ:
            lab1 = new Label();
            lab2 = new Label();
            if (childOneType == DijkstraType.INT && childTwoType == DijkstraType.INT) {
                mv.visitInsn(LCMP);
            } else {
                mv.visitInsn(DCMPL);
            }
            mv.visitJumpInsn(IFLT, lab1);
            mv.visitInsn(ICONST_1); // left >= right
            mv.visitJumpInsn(GOTO, lab2);
            mv.visitLabel(lab1);
            mv.visitInsn(ICONST_0); // right < left
            mv.visitLabel(lab2);
            break;
        case DijkstraParser.PLUS:
            if (childOneType == DijkstraType.INT && childTwoType == DijkstraType.INT) {
                mv.visitInsn(LADD);
            } else {
                mv.visitInsn(DADD);
            }
            break;
        case DijkstraParser.MINUS:
            if (childOneType == DijkstraType.INT && childTwoType == DijkstraType.INT) {
                mv.visitInsn(LSUB);
            } else {
                mv.visitInsn(DSUB);
            }
            break;
        case DijkstraParser.STAR:
            if (childOneType == DijkstraType.INT && childTwoType == DijkstraType.INT) {
                mv.visitInsn(LMUL);
            } else {
                mv.visitInsn(DMUL);
            }
            break;
        case DijkstraParser.SLASH:
            mv.visitInsn(DDIV);
            break;
        case DijkstraParser.MOD:
            mv.visitInsn(LREM);
            break;
        case DijkstraParser.DIV:
            mv.visitInsn(LDIV);
            break;
        case DijkstraParser.EQ:
            lab1 = new Label();
            lab2 = new Label();
            if (childOneType == DijkstraType.INT && childTwoType == DijkstraType.INT) {
                mv.visitInsn(LCMP);
                mv.visitJumpInsn(IFNE, lab1);
            } else if (childOneType == DijkstraType.BOOLEAN) {
                mv.visitJumpInsn(IF_ICMPNE, lab1);
            } else {
                mv.visitInsn(DCMPL);
                mv.visitJumpInsn(IFNE, lab1);
            }
            mv.visitInsn(ICONST_1);
            mv.visitJumpInsn(GOTO, lab2);
            mv.visitLabel(lab1);
            mv.visitInsn(ICONST_0);
            mv.visitLabel(lab2);
            break;
        case DijkstraParser.NEQ:
            lab1 = new Label();
            lab2 = new Label();
            if (childOneType == DijkstraType.INT && childTwoType == DijkstraType.INT) {
                mv.visitInsn(LCMP);
                mv.visitJumpInsn(IFEQ, lab1);
            } else if (childOneType == DijkstraType.BOOLEAN) {
                mv.visitJumpInsn(IF_ICMPEQ, lab1);
            } else {
                mv.visitInsn(DCMPL);
                mv.visitJumpInsn(IFEQ, lab1);
            }
            mv.visitInsn(ICONST_1); // left != right
            mv.visitJumpInsn(GOTO, lab2);
            mv.visitLabel(lab1);
            mv.visitInsn(ICONST_0); // left = right
            mv.visitLabel(lab2);
            break;
        }
    }
    return null;
}

From source file:dijkstra.gen.DijkstraCodeGenerator.java

License:Open Source License

public byte[] visit(ProcedureDeclarationNode procDeclNode) {
    if (processingClassFields) {
        return null;
    }//from   www . j a  v  a 2  s  . c  o m
    final String methodName = procDeclNode.getIDNode().getName();
    final StringBuilder sig = new StringBuilder();
    sig.append('(');
    for (IDNode param : procDeclNode.getParamList()) {
        if (param.getType() == DijkstraType.INT) {
            sig.append('J');
        } else if (param.getType() == DijkstraType.FLOAT) {
            sig.append('D');
        } else {
            sig.append('Z');
        }
    }
    sig.append(")V");
    if (inClass) {
        mvStack.push(cw.visitMethod(ACC_PUBLIC, methodName, sig.toString(), null, null));
    } else {
        mvStack.push(cw.visitMethod(ACC_PUBLIC + ACC_STATIC, methodName, sig.toString(), null, null));
    }
    final MethodVisitor mv = mvStack.peek();

    JVMInfo.enterScope(inClass);
    // Load the parameters into the JVMInfo so it knows the proper addresses
    for (IDNode param : procDeclNode.getParamList()) {
        param.getAddress();
    }
    mv.visitCode();
    final Label startLabel = new Label();
    mv.visitLabel(startLabel);

    procDeclNode.getCompoundNode().accept(this);

    mv.visitInsn(RETURN);
    final Label endLabel = new Label();
    mv.visitLabel(endLabel);
    int paramLoc = 0;
    for (IDNode param : procDeclNode.getParamList()) {
        if (param.getType() == DijkstraType.INT) {
            mv.visitLocalVariable(param.getName(), "J", null, startLabel, endLabel, paramLoc);
            paramLoc += 2;
        } else if (param.getType() == DijkstraType.FLOAT) {
            mv.visitLocalVariable(param.getName(), "D", null, startLabel, endLabel, paramLoc);
            paramLoc += 2;
        } else {
            mv.visitLocalVariable(param.getName(), "Z", null, startLabel, endLabel, paramLoc);
            paramLoc += 1;
        }
    }
    mv.visitMaxs(0, 0);
    mv.visitEnd();
    JVMInfo.exitScope();
    mvStack.pop();
    return null;
}

From source file:dijkstra.gen.DijkstraCodeGenerator.java

License:Open Source License

public byte[] visit(FunctionDeclarationNode funDeclNode) {
    if (processingClassFields) {
        return null;
    }//from www .ja va  2s.  co m
    final String methodName = funDeclNode.getIDNode().getName();
    final StringBuilder sig = new StringBuilder();
    sig.append('(');
    for (IDNode param : funDeclNode.getParamList()) {
        if (param.getType() == DijkstraType.INT) {
            sig.append('J');
        } else if (param.getType() == DijkstraType.FLOAT) {
            sig.append('D');
        } else {
            sig.append('Z');
        }
    }
    sig.append(')');
    sig.append("[Ljava/lang/Object;");

    if (inClass) {
        mvStack.push(cw.visitMethod(ACC_PUBLIC, methodName, sig.toString(), null, null));
    } else {
        mvStack.push(cw.visitMethod(ACC_PUBLIC + ACC_STATIC, methodName, sig.toString(), null, null));
    }
    final MethodVisitor mv = mvStack.peek();

    JVMInfo.enterScope(inClass);
    // Load the parameters into the JVMInfo so it knows the proper addresses
    for (IDNode param : funDeclNode.getParamList()) {
        param.getAddress();
    }

    mv.visitIntInsn(SIPUSH, funDeclNode.getReturnTypes().size());
    mv.visitTypeInsn(ANEWARRAY, "java/lang/Object");
    returnArrayStack.push(new ArraySymbol(null, UNDEFINED));
    mv.visitVarInsn(ASTORE, JVMInfo.getAddressForSymbol(returnArrayStack.peek()));

    mv.visitInsn(ICONST_0);
    returnIndexStack.push(new Symbol(null, UNDEFINED));
    mv.visitVarInsn(ISTORE, JVMInfo.getAddressForSymbol(returnIndexStack.peek()));

    mv.visitCode();
    final Label startLabel = new Label();
    mv.visitLabel(startLabel);

    funDeclNode.getCompoundNode().accept(this);

    returnIndexStack.pop();
    mv.visitVarInsn(ALOAD, JVMInfo.getAddressForSymbol(returnArrayStack.pop()));
    mv.visitInsn(ARETURN);
    final Label endLabel = new Label();
    mv.visitLabel(endLabel);
    int paramLoc = 0;
    for (IDNode param : funDeclNode.getParamList()) {
        if (param.getType() == DijkstraType.INT) {
            mv.visitLocalVariable(param.getName(), "J", null, startLabel, endLabel, paramLoc);
            paramLoc += 2;
        } else if (param.getType() == DijkstraType.FLOAT) {
            mv.visitLocalVariable(param.getName(), "D", null, startLabel, endLabel, paramLoc);
            paramLoc += 2;
        } else {
            mv.visitLocalVariable(param.getName(), "Z", null, startLabel, endLabel, paramLoc);
            paramLoc += 1;
        }
    }
    mv.visitMaxs(0, 0);
    mv.visitEnd();
    JVMInfo.exitScope();
    mvStack.pop();
    return null;
}

From source file:dodola.anole.lib.IncrementalSupportVisitor.java

License:Apache License

/***
 * Inserts a trampoline to this class so that the updated methods can make calls to
 * constructors./*from   w  ww .  j  av  a2 s  .co m*/
 * <p>
 * <p/>
 * Pseudo code for this trampoline:
 * <code>
 * ClassName(Object[] args, Marker unused) {
 * String name = (String) args[0];
 * if (name.equals(
 * "java/lang/ClassName.(Ljava/lang/String;Ljava/lang/Object;)Ljava/lang/Object;")) {
 * this((String)arg[1], arg[2]);
 * return
 * }
 * if (name.equals("SuperClassName.(Ljava/lang/String;I)V")) {
 * super((String)arg[1], (int)arg[2]);
 * return;
 * }
 * ...
 * StringBuilder $local1 = new StringBuilder();
 * $local1.append("Method not found ");
 * $local1.append(name);
 * $local1.append(" in " $classType $super implementation");
 * throw new $package/InstantReloadException($local1.toString());
 * }
 * </code>
 */
private void createDispatchingThis() {
    // Gather all methods from itself and its superclasses to generate a giant constructor
    // implementation.
    // This will work fine as long as we don't support adding constructors to classes.
    final Map<String, MethodNode> uniqueMethods = new HashMap<String, MethodNode>();

    addAllNewConstructors(uniqueMethods, classNode, true /*keepPrivateConstructors*/);
    for (ClassNode parentNode : parentNodes) {
        addAllNewConstructors(uniqueMethods, parentNode, false /*keepPrivateConstructors*/);
    }

    int access = Opcodes.ACC_PUBLIC | Opcodes.ACC_SYNTHETIC;

    Method m = new Method(AsmUtils.CONSTRUCTOR, ConstructorArgsRedirection.DISPATCHING_THIS_SIGNATURE);
    MethodVisitor visitor = super.visitMethod(0, m.getName(), m.getDescriptor(), null, null);
    final GeneratorAdapter mv = new GeneratorAdapter(access, m, visitor);

    mv.visitCode();
    // Mark this code as redirection code
    Label label = new Label();
    mv.visitLineNumber(0, label);

    // Get and store the constructor canonical name.
    mv.visitVarInsn(Opcodes.ALOAD, 1);
    mv.push(0);
    mv.visitInsn(Opcodes.AALOAD);
    mv.unbox(Type.getType("Ljava/lang/String;"));
    final int constructorCanonicalName = mv.newLocal(Type.getType("Ljava/lang/String;"));
    mv.storeLocal(constructorCanonicalName);

    new StringSwitch() {

        @Override
        void visitString() {
            mv.loadLocal(constructorCanonicalName);
        }

        @Override
        void visitCase(String canonicalName) {
            MethodNode methodNode = uniqueMethods.get(canonicalName);
            String owner = canonicalName.split("\\.")[0];

            // Parse method arguments and
            mv.visitVarInsn(Opcodes.ALOAD, 0);
            Type[] args = Type.getArgumentTypes(methodNode.desc);
            int argc = 0;
            for (Type t : args) {
                mv.visitVarInsn(Opcodes.ALOAD, 1);
                mv.push(argc + 1);
                mv.visitInsn(Opcodes.AALOAD);
                ByteCodeUtils.unbox(mv, t);
                argc++;
            }

            mv.visitMethodInsn(Opcodes.INVOKESPECIAL, owner, AsmUtils.CONSTRUCTOR, methodNode.desc, false);

            mv.visitInsn(Opcodes.RETURN);
        }

        @Override
        void visitDefault() {
            writeMissingMessageWithHash(mv, visitedClassName);
        }
    }.visit(mv, uniqueMethods.keySet());

    mv.visitMaxs(1, 3);
    mv.visitEnd();
}

From source file:dodola.anole.lib.Redirection.java

License:Apache License

/**
 * Adds the instructions to do a generic redirection.
 * <p/>/*from w ww  .jav a 2 s  .  co  m*/
 * Note that the generated bytecode does not have a direct translation to code, but as an
 * example, the following code block gets inserted.
 * <code>
 * if ($change != null) {
 * $change.access$dispatch($name, new object[] { arg0, ... argsN })
 * $anyCodeInsertedbyRestore
 * }
 * $originalMethodBody
 * </code>
 *
 * @param mv     the method visitor to add the instructions to.
 * @param change the local variable containing the alternate implementation.
 * @param args   the type of the local variable that need to be forwarded.
 */
void redirect(GeneratorAdapter mv, int change, List<Type> args) {
    // code to check if a new implementation of the current class is available.
    Label l0 = new Label();
    mv.loadLocal(change);
    mv.visitJumpInsn(Opcodes.IFNULL, l0);
    mv.loadLocal(change);
    mv.push(name);

    // create an array of objects capable of containing all the parameters and optionally the "this"
    createLocals(mv, args);

    // we need to maintain the stack index when loading parameters from, as for long and double
    // values, it uses 2 stack elements, all others use only 1 stack element.
    int stackIndex = 0;
    for (int arrayIndex = 0; arrayIndex < args.size(); arrayIndex++) {
        Type arg = args.get(arrayIndex);
        // duplicate the array of objects reference, it will be used to store the value in.
        mv.dup();
        // index in the array of objects to store the boxed parameter.
        mv.push(arrayIndex);
        // Pushes the appropriate local variable on the stack
        redirectLocal(mv, stackIndex, arg);
        // potentially box up intrinsic types.
        mv.box(arg);
        mv.arrayStore(Type.getType(Object.class));
        // stack index must progress according to the parameter type we just processed.
        stackIndex += arg.getSize();
    }

    // now invoke the generic dispatch method.
    mv.invokeInterface(IncrementalVisitor.CHANGE_TYPE,
            Method.getMethod("Object access$dispatch(String, Object[])"));

    // Restore the state after the redirection
    restore(mv, args);
    // jump label for classes without any new implementation, just invoke the original
    // method implementation.
    mv.visitLabel(l0);
}

From source file:dodola.anole.lib.StringSwitch.java

License:Apache License

/**
 * Emit code for a string if-else block.
 *
 *     if (s.equals("collided_method1")) {
 *         visit(s);//from w ww .java2  s. com
 *     } else if (s.equals("collided_method2")) {
 *         visit(s);
 *     }
 *
 * In the most common case of just one string, this degenerates to:
 *
 *      visit(s)
 *
 */
private void visitx(GeneratorAdapter mv, List<String> strings) {
    if (strings.size() == 1) {
        visitCase(strings.get(0));
        return;
    }
    for (int i = 0; i < strings.size(); ++i) {
        String string = strings.get(i);
        Label label = new Label();
        visitString();
        mv.visitLdcInsn(string);
        mv.invokeVirtual(STRING_TYPE, Method.getMethod("boolean equals(Object)"));
        mv.visitJumpInsn(Opcodes.IFEQ, label);
        visitCase(string);
        mv.visitLabel(label);
    }

    visitDefault();
}

From source file:dodola.anole.lib.StringSwitch.java

License:Apache License

/**
 * Emit code for a string switch for the given string classifier.
 *
 * switch(s.hashCode()) {//from  w  w w. j  av  a2s .  c o  m
 *   case 192: visitCase(s);
 *   case 312: visitCase(s);
 *   case 1024:
 *     if (s.equals("collided_method1")) {
 *         visit(s);
 *     } else if (s.equals("collided_method2")) {
 *         visit(s);
 *     }
 *     visitDefault();
 *   default:
 *     visitDefault();
 * }
 *
 **/
private void visitClassifier(GeneratorAdapter mv, Set<String> strings) {
    visitString();
    visitHashMethod(mv);

    // Group strings by hash code.
    Multimap<Integer, String> buckets = Multimaps.index(strings, hashMethod);
    List<Map.Entry<Integer, Collection<String>>> sorted = Ordering.natural()
            .onResultOf(new Function<Map.Entry<Integer, Collection<String>>, Integer>() {
                @Override
                public Integer apply(Map.Entry<Integer, Collection<String>> entry) {
                    return entry.getKey();
                }
            }).immutableSortedCopy(buckets.asMap().entrySet());

    int sortedHashes[] = new int[sorted.size()];
    List<String> sortedCases[] = new List[sorted.size()];
    int index = 0;
    for (Map.Entry<Integer, Collection<String>> entry : sorted) {
        sortedHashes[index] = entry.getKey();
        sortedCases[index] = Lists.newCopyOnWriteArrayList(entry.getValue());
        index++;
    }

    // Label for each hash and for default.
    Label labels[] = new Label[sorted.size()];
    Label defaultLabel = new Label();
    for (int i = 0; i < sorted.size(); ++i) {
        labels[i] = new Label();
    }

    // Create a switch that dispatches to each label from the hash code of
    mv.visitLookupSwitchInsn(defaultLabel, sortedHashes, labels);

    // Create the cases.
    for (int i = 0; i < sorted.size(); ++i) {
        mv.visitLabel(labels[i]);
        visitx(mv, sortedCases[i]);
    }
    mv.visitLabel(defaultLabel);
    visitDefault();
}

From source file:dyco4j.instrumentation.internals.TracingMethodVisitor.java

License:BSD License

@Override
public final void visitMaxs(final int maxStack, final int maxLocals) {
    endOutermostExceptionHandler();/*from ww  w  .  j  a v a 2s. c  o m*/
    for (final Map.Entry<Label, Label> _e : beginLabel2endLabel.entrySet()) {
        final Label _handlerLabel = new Label();
        super.visitLabel(_handlerLabel);
        super.visitTryCatchBlock(_e.getKey(), _e.getValue(), _handlerLabel, "java/lang/Throwable");
        LoggingHelper.emitLogException(this.mv);
        LoggingHelper.emitLogMethodExit(this.mv, this.methodId, LoggingHelper.ExitKind.EXCEPTIONAL);
        super.visitInsn(Opcodes.ATHROW);
    }
    super.visitMaxs(maxStack, maxLocals);
}

From source file:dyco4j.instrumentation.internals.TracingMethodVisitor.java

License:BSD License

void beginOutermostExceptionHandler() {
    this.outermostExceptionHandlerBeginLabel = new Label();
    super.visitLabel(this.outermostExceptionHandlerBeginLabel);
}

From source file:dyco4j.instrumentation.internals.TracingMethodVisitor.java

License:BSD License

void endOutermostExceptionHandler() {
    assert this.outermostExceptionHandlerBeginLabel != null;
    final Label _l = new Label();
    super.visitLabel(_l);
    this.beginLabel2endLabel.put(this.outermostExceptionHandlerBeginLabel, _l);
    this.outermostExceptionHandlerBeginLabel = null;
}