235 lines · 7.5 KB · Java
RawDownload
/* * 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.Label;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. */publicclass ConditionalExpression extends BinaryExpression {    Expression cond;     /**     * Constructor     */    public ConditionalExpression(long where, Expression cond, Expression left, Expression right) {        super(COND, where, Type.tError, left, right);        this.cond = cond;    }     /**     * Order the expression based on precedence     */    public Expression order() {        if (precedence() > cond.precedence()) {            UnaryExpression e = (UnaryExpression)cond;            cond = e.right;            e.right = order();            return e;        }        return this;    }     /**     * Check the expression     */    public Vset checkValue(Environment env, Context ctx, Vset vset, Hashtable exp) {        ConditionVars cvars = cond.checkCondition(env, ctx, vset, exp);        vset = left.checkValue(env, ctx, cvars.vsTrue, exp).join(               right.checkValue(env, ctx, cvars.vsFalse, exp) );        cond = convert(env, ctx, Type.tBoolean, cond);         int tm = left.type.getTypeMask() | right.type.getTypeMask();        if ((tm & TM_ERROR) != 0) {            type = Type.tError;            return vset;        }        if (left.type.equals(right.type)) {            type = left.type;        } else if ((tm & TM_DOUBLE) != 0) {            type = Type.tDouble;        } else if ((tm & TM_FLOAT) != 0) {            type = Type.tFloat;        } else if ((tm & TM_LONG) != 0) {            type = Type.tLong;        } else if ((tm & TM_REFERENCE) != 0) {            try {                // This is wrong.  We should be using their most common                // ancestor, instead.                type = env.implicitCast(right.type, left.type)                    ? left.type : right.type;            } catch (ClassNotFound e) {                type = Type.tError;            }        } else if (((tm & TM_CHAR) != 0) && left.fitsType(env, ctx, Type.tChar) && right.fitsType(env, ctx, Type.tChar)) {            type = Type.tChar;        } else if (((tm & TM_SHORT) != 0) && left.fitsType(env, ctx, Type.tShort) && right.fitsType(env, ctx, Type.tShort)) {            type = Type.tShort;        } else if (((tm & TM_BYTE) != 0) && left.fitsType(env, ctx, Type.tByte) && right.fitsType(env, ctx, Type.tByte)) {            type = Type.tByte;        } else {            type = Type.tInt;        }         left = convert(env, ctx, type, left);        right = convert(env, ctx, type, right);        return vset;    }     public Vset check(Environment env, Context ctx, Vset vset, Hashtable exp) {        vset = cond.checkValue(env, ctx, vset, exp);        cond = convert(env, ctx, Type.tBoolean, cond);        return left.check(env, ctx, vset.copy(), exp).join(right.check(env, ctx, vset, exp));    }     /**     * Check if constant     */    public boolean isConstant() {        return cond.isConstant() && left.isConstant() && right.isConstant();    }     /**     * Simplify     */    Expression simplify() {        if (cond.equals(true)) {            return left;        }        if (cond.equals(false)) {            return right;        }        return this;    }     /**     * Inline     */    public Expression inline(Environment env, Context ctx) {        left = left.inline(env, ctx);        right = right.inline(env, ctx);        if ((left == null) && (right == null)) {            return cond.inline(env, ctx);        }        if (left == null) {            left = right;            right = null;            cond = new NotExpression(where, cond);        }        cond = cond.inlineValue(env, ctx);        return simplify();    }     public Expression inlineValue(Environment env, Context ctx) {        cond = cond.inlineValue(env, ctx);        left = left.inlineValue(env, ctx);        right = right.inlineValue(env, ctx);        return simplify();    }     /**     * The cost of inlining this expression     */    public int costInline(int thresh, Environment env, Context ctx) {        // We need to check if right is null in case costInline()        // is called after this expression has been inlined.        // This call can happen, for example, in MemberDefinition#cleanup().        // (Fix for 4069861).        return 1 +            cond.costInline(thresh, env, ctx) +            left.costInline(thresh, env, ctx) +            ((right == null) ? 0 : right.costInline(thresh, env, ctx));    }     /**     * Create a copy of the expression for method inlining     */    public Expression copyInline(Context ctx) {        ConditionalExpression e = (ConditionalExpression)clone();        e.cond = cond.copyInline(ctx);        e.left = left.copyInline(ctx);         // If copyInline() is called after inlining is complete,        // right could be null.        e.right = (right == null) ? null : right.copyInline(ctx);         return e;    }     /**     * Code     */    public void codeValue(Environment env, Context ctx, Assembler asm) {        Label l1 = new Label();        Label l2 = new Label();         cond.codeBranch(env, ctx, asm, l1, false);        left.codeValue(env, ctx, asm);        asm.add(where, opc_goto, l2);        asm.add(l1);        right.codeValue(env, ctx, asm);        asm.add(l2);    }    public void code(Environment env, Context ctx, Assembler asm) {        Label l1 = new Label();        cond.codeBranch(env, ctx, asm, l1, false);        left.code(env, ctx, asm);        if (right != null) {            Label l2 = new Label();            asm.add(where, opc_goto, l2);            asm.add(l1);            right.code(env, ctx, asm);            asm.add(l2);        } else {            asm.add(l1);        }    }     /**     * Print     */    public void print(PrintStream out) {        out.print("(" + opNames[op] + " ");        cond.print(out);        out.print(" ");        left.print(out);        out.print(" ");        if (right != null) {            right.print(out);        } else {            out.print("<null>");        }        out.print(")");    }}