ojluni/src/main/java/sun/tools/tree/VarDeclarationStatement.java - platform/libcore.git - Git at Google

 /*
  * Copyright (c) 1994, 2003, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle in the LICENSE file that accompanied this code.
  *
  * This code 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
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */

 package sun.tools.tree;

 import sun.tools.java.*;
 import sun.tools.asm.Assembler;
 import sun.tools.asm.LocalVariable;
 import java.io.PrintStream;
 import java.util.Hashtable;

 /**
  * WARNING: The contents of this source file are not part of any
  * supported API.  Code that depends on them does so at its own risk:
  * they are subject to change or removal without notice.
  */
 public
 class VarDeclarationStatement extends Statement {
     LocalMember field;
     Expression expr;

     /**
      * Constructor
      */
     public VarDeclarationStatement(long where, Expression expr) {
         super(VARDECLARATION, where);
         this.expr = expr;
     }
     public VarDeclarationStatement(long where, LocalMember field, Expression expr) {
         super(VARDECLARATION, where);
         this.field = field;
         this.expr = expr;
     }

     /**
      * Check statement
      */
     Vset checkDeclaration(Environment env, Context ctx, Vset vset, int mod, Type t, Hashtable exp) {
         if (labels != null) {
             env.error(where, "declaration.with.label", labels[0]);
         }
         if (field != null) {
             if (ctx.getLocalClass(field.getName()) != null
                 && field.isInnerClass()) {
                 env.error(where, "local.class.redefined", field.getName());
             }

             ctx.declare(env, field);
             if (field.isInnerClass()) {
                 ClassDefinition body = field.getInnerClass();
                 try {
                     vset = body.checkLocalClass(env, ctx, vset,
                                                 null, null, null);
                 } catch (ClassNotFound ee) {
                     env.error(where, "class.not.found", ee.name, opNames[op]);
                 }
                 return vset;
             }
             vset.addVar(field.number);
             return (expr != null) ? expr.checkValue(env, ctx, vset, exp) : vset;
         }

         // Argument 'expr' is either an IdentifierExpression for a declaration of
         // the form 'type x' or an AssignmentExpression for a declaration of the
         // form 'type x = initvalue'.  Note that these expressions are treated
         // specially in this context, and don't have much connection to their ordinary
         // meaning.

         Expression e = expr;

         if (e.op == ASSIGN) {
             expr = ((AssignExpression)e).right;
             e = ((AssignExpression)e).left;
         } else {
             expr = null;
         }

         boolean declError = t.isType(TC_ERROR);
         while (e.op == ARRAYACCESS) {
             ArrayAccessExpression array = (ArrayAccessExpression)e;
             if (array.index != null) {
                 env.error(array.index.where, "array.dim.in.type");
                 declError = true;
             }
             e = array.right;
             t = Type.tArray(t);
         }
         if (e.op == IDENT) {
             Identifier id = ((IdentifierExpression)e).id;
             if (ctx.getLocalField(id) != null) {
                 env.error(where, "local.redefined", id);
             }

             field = new LocalMember(e.where, ctx.field.getClassDefinition(), mod, t, id);
             ctx.declare(env, field);

             if (expr != null) {
                 vset = expr.checkInitializer(env, ctx, vset, t, exp);
                 expr = convert(env, ctx, t, expr);
                 field.setValue(expr); // for the sake of non-blank finals
                 if (field.isConstant()) {
                     // Keep in mind that isConstant() only means expressions
                     // that are constant according to the JLS.  They might
                     // not be either constants or evaluable (eg. 1/0).
                     field.addModifiers(M_INLINEABLE);
                 }
                 vset.addVar(field.number);
             } else if (declError) {
                 vset.addVar(field.number);
             } else {
                 vset.addVarUnassigned(field.number);
             }
             return vset;
         }
         env.error(e.where, "invalid.decl");
         return vset;
     }

     /**
      * Inline
      */
     public Statement inline(Environment env, Context ctx) {
         if (field.isInnerClass()) {
             ClassDefinition body = field.getInnerClass();
             body.inlineLocalClass(env);
             return null;
         }

         // Don't generate code for variable if unused and
         // optimization is on, whether or not debugging is on
         if (env.opt() && !field.isUsed()) {
             return new ExpressionStatement(where, expr).inline(env, ctx);
         }

         ctx.declare(env, field);

         if (expr != null) {
             expr = expr.inlineValue(env, ctx);
             field.setValue(expr); // for the sake of non-blank finals
             if (env.opt() && (field.writecount == 0)) {
                 if (expr.op == IDENT) {

                     // This code looks like it tests whether a final variable
                     // is being initialized by an identifier expression.
                     // Then if the identifier is a local of the same method
                     // it makes the final variable eligible to be inlined.
                     // BUT: why isn't the local also checked to make sure
                     // it is itself final?  Unknown.

                     IdentifierExpression e = (IdentifierExpression)expr;
                     if (e.field.isLocal() && ((ctx = ctx.getInlineContext()) != null) &&
                         (((LocalMember)e.field).number < ctx.varNumber)) {
                         //System.out.println("FINAL IDENT = " + field + " in " + ctx.field);
                         field.setValue(expr);
                         field.addModifiers(M_INLINEABLE);

                         // The two lines below used to elide the declaration
                         // of inlineable variables, on the theory that there
                         // wouldn't be any references.  But this breaks the
                         // translation of nested classes, which might refer to
                         // the variable.

                         //expr = null;
                         //return null;
                     }
                 }
                 if (expr.isConstant() || (expr.op == THIS) || (expr.op == SUPER)) {
                     //System.out.println("FINAL = " + field + " in " + ctx.field);
                     field.setValue(expr);
                     field.addModifiers(M_INLINEABLE);

                     // The two lines below used to elide the declaration
                     // of inlineable variables, on the theory that there
                     // wouldn't be any references.  But this breaks the
                     // translation of nested classes, which might refer to
                     // the variable.  Fix for 4073244.

                     //expr = null;
                     //return null;
                 }
             }
         }
         return this;
     }

     /**
      * Create a copy of the statement for method inlining
      */
     public Statement copyInline(Context ctx, boolean valNeeded) {
         VarDeclarationStatement s = (VarDeclarationStatement)clone();
         if (expr != null) {
             s.expr = expr.copyInline(ctx);
         }
         return s;
     }

     /**
      * The cost of inlining this statement
      */
     public int costInline(int thresh, Environment env, Context ctx) {
         if (field != null && field.isInnerClass()) {
             return thresh;      // don't copy classes...
         }
         return (expr != null) ? expr.costInline(thresh, env, ctx) : 0;
     }

     /**
      * Code
      */
     public void code(Environment env, Context ctx, Assembler asm) {
         if (expr != null && !expr.type.isType(TC_VOID)) {
             // The two lines of code directly following this comment used
             // to be in the opposite order.  They were switched so that
             // lines like the following:
             //
             //     int j = (j = 4);
             //
             // will compile correctly.  (Constructions like the above are
             // legal.  JLS 14.3.2 says that the scope of a local variable
             // includes its own initializer.)  It is important that we
             // declare `field' before we code `expr', because otherwise
             // situations can arise where `field' thinks it is assigned
             // a local variable slot that is, in actuality, assigned to
             // an entirely different variable.  (Bug id 4076729)
             ctx.declare(env, field);
             expr.codeValue(env, ctx, asm);

             asm.add(where, opc_istore + field.getType().getTypeCodeOffset(),
                     new LocalVariable(field, field.number));
         } else {
             ctx.declare(env, field);
             if (expr != null) {
                 // an initial side effect, rather than an initial value
                 expr.code(env, ctx, asm);
             }
         }
     }

     /**
      * Print
      */
     public void print(PrintStream out, int indent) {
         out.print("local ");
         if (field != null) {
             out.print(field + "#" + field.hashCode());
             if (expr != null) {
                 out.print(" = ");
                 expr.print(out);
             }
         } else {
             expr.print(out);
             out.print(";");
         }
     }
 }
	/*
	* Copyright (c) 1994, 2003, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package sun.tools.tree;

	import sun.tools.java.*;
	import sun.tools.asm.Assembler;
	import sun.tools.asm.LocalVariable;
	import java.io.PrintStream;
	import java.util.Hashtable;

	/**
	* WARNING: The contents of this source file are not part of any
	* supported API. Code that depends on them does so at its own risk:
	* they are subject to change or removal without notice.
	*/
	public
	class VarDeclarationStatement extends Statement {
	LocalMember field;
	Expression expr;

	/**
	* Constructor
	*/
	public VarDeclarationStatement(long where, Expression expr) {
	super(VARDECLARATION, where);
	this.expr = expr;
	}
	public VarDeclarationStatement(long where, LocalMember field, Expression expr) {
	super(VARDECLARATION, where);
	this.field = field;
	this.expr = expr;
	}

	/**
	* Check statement
	*/
	Vset checkDeclaration(Environment env, Context ctx, Vset vset, int mod, Type t, Hashtable exp) {
	if (labels != null) {
	env.error(where, "declaration.with.label", labels[0]);
	}
	if (field != null) {
	if (ctx.getLocalClass(field.getName()) != null
	&& field.isInnerClass()) {
	env.error(where, "local.class.redefined", field.getName());
	}

	ctx.declare(env, field);
	if (field.isInnerClass()) {
	ClassDefinition body = field.getInnerClass();
	try {
	vset = body.checkLocalClass(env, ctx, vset,
	null, null, null);
	} catch (ClassNotFound ee) {
	env.error(where, "class.not.found", ee.name, opNames[op]);
	}
	return vset;
	}
	vset.addVar(field.number);
	return (expr != null) ? expr.checkValue(env, ctx, vset, exp) : vset;
	}

	// Argument 'expr' is either an IdentifierExpression for a declaration of
	// the form 'type x' or an AssignmentExpression for a declaration of the
	// form 'type x = initvalue'. Note that these expressions are treated
	// specially in this context, and don't have much connection to their ordinary
	// meaning.

	Expression e = expr;

	if (e.op == ASSIGN) {
	expr = ((AssignExpression)e).right;
	e = ((AssignExpression)e).left;
	} else {
	expr = null;
	}

	boolean declError = t.isType(TC_ERROR);
	while (e.op == ARRAYACCESS) {
	ArrayAccessExpression array = (ArrayAccessExpression)e;
	if (array.index != null) {
	env.error(array.index.where, "array.dim.in.type");
	declError = true;
	}
	e = array.right;
	t = Type.tArray(t);
	}
	if (e.op == IDENT) {
	Identifier id = ((IdentifierExpression)e).id;
	if (ctx.getLocalField(id) != null) {
	env.error(where, "local.redefined", id);
	}

	field = new LocalMember(e.where, ctx.field.getClassDefinition(), mod, t, id);
	ctx.declare(env, field);

	if (expr != null) {
	vset = expr.checkInitializer(env, ctx, vset, t, exp);
	expr = convert(env, ctx, t, expr);
	field.setValue(expr); // for the sake of non-blank finals
	if (field.isConstant()) {
	// Keep in mind that isConstant() only means expressions
	// that are constant according to the JLS. They might
	// not be either constants or evaluable (eg. 1/0).
	field.addModifiers(M_INLINEABLE);
	}
	vset.addVar(field.number);
	} else if (declError) {
	vset.addVar(field.number);
	} else {
	vset.addVarUnassigned(field.number);
	}
	return vset;
	}
	env.error(e.where, "invalid.decl");
	return vset;
	}

	/**
	* Inline
	*/
	public Statement inline(Environment env, Context ctx) {
	if (field.isInnerClass()) {
	ClassDefinition body = field.getInnerClass();
	body.inlineLocalClass(env);
	return null;
	}

	// Don't generate code for variable if unused and
	// optimization is on, whether or not debugging is on
	if (env.opt() && !field.isUsed()) {
	return new ExpressionStatement(where, expr).inline(env, ctx);
	}

	ctx.declare(env, field);

	if (expr != null) {
	expr = expr.inlineValue(env, ctx);
	field.setValue(expr); // for the sake of non-blank finals
	if (env.opt() && (field.writecount == 0)) {
	if (expr.op == IDENT) {

	// This code looks like it tests whether a final variable
	// is being initialized by an identifier expression.
	// Then if the identifier is a local of the same method
	// it makes the final variable eligible to be inlined.
	// BUT: why isn't the local also checked to make sure
	// it is itself final? Unknown.

	IdentifierExpression e = (IdentifierExpression)expr;
	if (e.field.isLocal() && ((ctx = ctx.getInlineContext()) != null) &&
	(((LocalMember)e.field).number < ctx.varNumber)) {
	//System.out.println("FINAL IDENT = " + field + " in " + ctx.field);
	field.setValue(expr);
	field.addModifiers(M_INLINEABLE);

	// The two lines below used to elide the declaration
	// of inlineable variables, on the theory that there
	// wouldn't be any references. But this breaks the
	// translation of nested classes, which might refer to
	// the variable.

	//expr = null;
	//return null;
	}
	}
	if (expr.isConstant() \|\| (expr.op == THIS) \|\| (expr.op == SUPER)) {
	//System.out.println("FINAL = " + field + " in " + ctx.field);
	field.setValue(expr);
	field.addModifiers(M_INLINEABLE);

	// The two lines below used to elide the declaration
	// of inlineable variables, on the theory that there
	// wouldn't be any references. But this breaks the
	// translation of nested classes, which might refer to
	// the variable. Fix for 4073244.

	//expr = null;
	//return null;
	}
	}
	}
	return this;
	}

	/**
	* Create a copy of the statement for method inlining
	*/
	public Statement copyInline(Context ctx, boolean valNeeded) {
	VarDeclarationStatement s = (VarDeclarationStatement)clone();
	if (expr != null) {
	s.expr = expr.copyInline(ctx);
	}
	return s;
	}

	/**
	* The cost of inlining this statement
	*/
	public int costInline(int thresh, Environment env, Context ctx) {
	if (field != null && field.isInnerClass()) {
	return thresh; // don't copy classes...
	}
	return (expr != null) ? expr.costInline(thresh, env, ctx) : 0;
	}

	/**
	* Code
	*/
	public void code(Environment env, Context ctx, Assembler asm) {
	if (expr != null && !expr.type.isType(TC_VOID)) {
	// The two lines of code directly following this comment used
	// to be in the opposite order. They were switched so that
	// lines like the following:
	//
	// int j = (j = 4);
	//
	// will compile correctly. (Constructions like the above are
	// legal. JLS 14.3.2 says that the scope of a local variable
	// includes its own initializer.) It is important that we
	// declare `field' before we code `expr', because otherwise
	// situations can arise where `field' thinks it is assigned
	// a local variable slot that is, in actuality, assigned to
	// an entirely different variable. (Bug id 4076729)
	ctx.declare(env, field);
	expr.codeValue(env, ctx, asm);

	asm.add(where, opc_istore + field.getType().getTypeCodeOffset(),
	new LocalVariable(field, field.number));
	} else {
	ctx.declare(env, field);
	if (expr != null) {
	// an initial side effect, rather than an initial value
	expr.code(env, ctx, asm);
	}
	}
	}

	/**
	* Print
	*/
	public void print(PrintStream out, int indent) {
	out.print("local ");
	if (field != null) {
	out.print(field + "#" + field.hashCode());
	if (expr != null) {
	out.print(" = ");
	expr.print(out);
	}
	} else {
	expr.print(out);
	out.print(";");
	}
	}
	}