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/* * 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 ForStatement extends Statement {    Statement init;    Expression cond;    Expression inc;    Statement body;     /**     * Constructor     */    public ForStatement(long where, Statement init, Expression cond, Expression inc, Statement body) {        super(FOR, where);        this.init = init;        this.cond = cond;        this.inc = inc;        this.body = body;    }     /**     * Check statement     */    Vset check(Environment env, Context ctx, Vset vset, Hashtable exp) {        checkLabel(env, ctx);        vset = reach(env, vset);        Context initctx = new Context(ctx, this);        if (init != null) {            vset = init.checkBlockStatement(env, initctx, vset, exp);        }        CheckContext newctx = new CheckContext(initctx, this);        // remember what was unassigned on entry        Vset vsEntry = vset.copy();        ConditionVars cvars;        if (cond != null) {            cvars = cond.checkCondition(env, newctx, vset, exp);            cond = convert(env, newctx, Type.tBoolean, cond);        } else {            // a missing test is equivalent to "true"            cvars = new ConditionVars();            cvars.vsFalse = Vset.DEAD_END;            cvars.vsTrue = vset;        }        vset = body.check(env, newctx, cvars.vsTrue, exp);        vset = vset.join(newctx.vsContinue);        if (inc != null) {            vset = inc.check(env, newctx, vset, exp);        }        // Make sure the back-branch fits the entry of the loop.        // Must include variables declared in the for-init part in the        // set of variables visible upon loop entry that must be checked.        initctx.checkBackBranch(env, this, vsEntry, vset);        // exit by testing false or executing a break;        vset = newctx.vsBreak.join(cvars.vsFalse);        return ctx.removeAdditionalVars(vset);    }     /**     * Inline     */    public Statement inline(Environment env, Context ctx) {        ctx = new Context(ctx, this);        if (init != null) {            Statement body[] = {init, this};            init = null;            return new CompoundStatement(where, body).inline(env, ctx);        }        if (cond != null) {            cond = cond.inlineValue(env, ctx);        }        if (body != null) {            body = body.inline(env, ctx);        }        if (inc != null) {            inc = inc.inline(env, ctx);        }        return this;    }     /**     * Create a copy of the statement for method inlining     */    public Statement copyInline(Context ctx, boolean valNeeded) {        ForStatement s = (ForStatement)clone();        if (init != null) {            s.init = init.copyInline(ctx, valNeeded);        }        if (cond != null) {            s.cond = cond.copyInline(ctx);        }        if (body != null) {            s.body = body.copyInline(ctx, valNeeded);        }        if (inc != null) {            s.inc = inc.copyInline(ctx);        }        return s;    }     /**     * The cost of inlining this statement     */    public int costInline(int thresh, Environment env, Context ctx) {        int cost = 2;        if (init != null) {            cost += init.costInline(thresh, env, ctx);        }        if (cond != null) {            cost += cond.costInline(thresh, env, ctx);        }        if (body != null) {            cost += body.costInline(thresh, env, ctx);        }        if (inc != null) {            cost += inc.costInline(thresh, env, ctx);        }        return cost;    }     /**     * Code     */    public void code(Environment env, Context ctx, Assembler asm) {        CodeContext newctx = new CodeContext(ctx, this);        if (init != null) {            init.code(env, newctx, asm);        }         Label l1 = new Label();        Label l2 = new Label();         asm.add(where, opc_goto, l2);         asm.add(l1);        if (body != null) {            body.code(env, newctx, asm);        }         asm.add(newctx.contLabel);        if (inc != null) {            inc.code(env, newctx, asm);        }         asm.add(l2);        if (cond != null) {            cond.codeBranch(env, newctx, asm, l1, true);        } else {            asm.add(where, opc_goto, l1);        }        asm.add(newctx.breakLabel);    }     /**     * Print     */    public void print(PrintStream out, int indent) {        super.print(out, indent);        out.print("for (");        if (init != null) {            init.print(out, indent);            out.print(" ");        } else {            out.print("; ");        }        if (cond != null) {            cond.print(out);            out.print(" ");        }        out.print("; ");        if (inc != null) {            inc.print(out);        }        out.print(") ");        if (body != null) {            body.print(out, indent);        } else {            out.print(";");        }    }}