content: /*
   *  This file is part of AndroidIDE.
   *
   *  AndroidIDE is free software: you can redistribute it and/or modify
   *  it under the terms of the GNU General Public License as published by
   *  the Free Software Foundation, either version 3 of the License, or
   *  (at your option) any later version.
   *
   *  AndroidIDE is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *   along with AndroidIDE.  If not, see <https://www.gnu.org/licenses/>.
   */
  
  /*
   * reserved comment block
   * DO NOT REMOVE OR ALTER!
   */
  /*
   * Copyright 2001-2004 The Apache Software Foundation.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  /*
   * $Id: Variable.java,v 1.2.4.1 2005/09/12 11:36:46 pvedula Exp $
   */
  
  package jaxp.sun.org.apache.xalan.internal.xsltc.compiler;
  
  import jaxp.sun.org.apache.bcel.internal.classfile.Field;
  import jaxp.sun.org.apache.bcel.internal.generic.ACONST_NULL;
  import jaxp.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
  import jaxp.sun.org.apache.bcel.internal.generic.DCONST;
  import jaxp.sun.org.apache.bcel.internal.generic.ICONST;
  import jaxp.sun.org.apache.bcel.internal.generic.InstructionHandle;
  import jaxp.sun.org.apache.bcel.internal.generic.InstructionList;
  import jaxp.sun.org.apache.bcel.internal.generic.PUTFIELD;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.BooleanType;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.ErrorMsg;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.IntType;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.NodeType;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.RealType;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
  import jaxp.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
  
  final class Variable extends VariableBase {
  
      public int getIndex() {
          return (_local != null) ? _local.getIndex() : -1;
      }
  
      /**
       * Parse the contents of the variable
       */
      public void parseContents(Parser parser) {
          // Parse 'name' and 'select' attributes plus parameter contents
          super.parseContents(parser);
  
          // Add a ref to this var to its enclosing construct
          SyntaxTreeNode parent = getParent();
          if (parent instanceof Stylesheet) {
              // Mark this as a global variable
              _isLocal = false;
              // Check if a global variable with this name already exists...
              Variable var = parser.getSymbolTable().lookupVariable(_name);
              // ...and if it does we need to check import precedence
              if (var != null) {
                  final int us = this.getImportPrecedence();
                  final int them = var.getImportPrecedence();
                  // It is an error if the two have the same import precedence
                  if (us == them) {
                      final String name = _name.toString();
                      reportError(this, parser, ErrorMsg.VARIABLE_REDEF_ERR,name);
                  }
                  // Ignore this if previous definition has higher precedence
                  else if (them > us) {
                      _ignore = true;
                      copyReferences(var);
                      return;
                  }
                  else {
                      var.copyReferences(this);
                      var.disable();
                  }
                  // Add this variable if we have higher precedence
              }
              ((Stylesheet)parent).addVariable(this);
              parser.getSymbolTable().addVariable(this);
          }
          else {
              _isLocal = true;
          }
      }
  
      /**
       * Runs a type check on either the variable element body or the
       * expression in the 'select' attribute
       */
      public Type typeCheck(SymbolTable stable) throws TypeCheckError {
  
          // Type check the 'select' expression if present
          if (_select != null) {
              _type = _select.typeCheck(stable);
          }
          // Type check the element contents otherwise
          else if (hasContents()) {
              typeCheckContents(stable);
              _type = Type.ResultTree;
          }
          else {
              _type = Type.Reference;
          }
          // The return type is void as the variable element does not leave
          // anything on the JVM's stack. The '_type' global will be returned
          // by the references to this variable, and not by the variable itself.
          return Type.Void;
      }
  
      /**
       * This method is part of a little trick that is needed to use local
       * variables inside nested for-each loops. See the initializeVariables()
       * method in the ForEach class for an explanation
       */
      public void initialize(ClassGenerator classGen, MethodGenerator methodGen) {
          final ConstantPoolGen cpg = classGen.getConstantPool();
          final InstructionList il = methodGen.getInstructionList();
  
          // This is only done for local variables that are actually used
          if (isLocal() && !_refs.isEmpty()) {
              // Create a variable slot if none is allocated
              if (_local == null) {
                  _local = methodGen.addLocalVariable2(getEscapedName(),
                                                       _type.toJCType(),
                                                       null);
              }
              // Push the default value on the JVM's stack
              if ((_type instanceof IntType) ||
                  (_type instanceof NodeType) ||
                  (_type instanceof BooleanType))
                  il.append(new ICONST(0)); // 0 for node-id, integer and boolean
              else if (_type instanceof RealType)
                  il.append(new DCONST(0)); // 0.0 for floating point numbers
              else
                  il.append(new ACONST_NULL()); // and 'null' for anything else
  
              // Mark the store as the start of the live range of the variable
              _local.setStart(il.append(_type.STORE(_local.getIndex())));
  
          }
      }
  
      public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
          final ConstantPoolGen cpg = classGen.getConstantPool();
          final InstructionList il = methodGen.getInstructionList();
  
          // Don't generate code for unreferenced variables
          if (_refs.isEmpty()) {
              _ignore = true;
          }
  
          // Make sure that a variable instance is only compiled once
          if (_ignore) return;
          _ignore = true;
  
          final String name = getEscapedName();
  
          if (isLocal()) {
              // Compile variable value computation
              translateValue(classGen, methodGen);
  
              // Add a new local variable and store value
              boolean createLocal = _local == null;
              if (createLocal) {
                  mapRegister(methodGen);
              }
              InstructionHandle storeInst =
              il.append(_type.STORE(_local.getIndex()));
  
              // If the local is just being created, mark the store as the start
              // of its live range.  Note that it might have been created by
              // initializeVariables already, which would have set the start of
              // the live range already.
              if (createLocal) {
                  _local.setStart(storeInst);
          }
          }
          else {
              String signature = _type.toSignature();
  
              // Global variables are store in class fields
              if (classGen.containsField(name) == null) {
                  classGen.addField(new Field(ACC_PUBLIC,
                                              cpg.addUtf8(name),
                                              cpg.addUtf8(signature),
                                              null, cpg.getConstantPool()));
  
                  // Push a reference to "this" for putfield
                  il.append(classGen.loadTranslet());
                  // Compile variable value computation
                  translateValue(classGen, methodGen);
                  // Store the variable in the allocated field
                  il.append(new PUTFIELD(cpg.addFieldref(classGen.getClassName(),
                                                         name, signature)));
              }
          }
      }
  }
  