/* * 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 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 IncDecExpression extends UnaryExpression {     private FieldUpdater updater = null;     /**     * Constructor     */    public IncDecExpression(int op, long where, Expression right) {        super(op, where, right.type, right);    }     /**     * Check an increment or decrement expression     */    public Vset checkValue(Environment env, Context ctx, Vset vset, Hashtable exp) {        vset = right.checkAssignOp(env, ctx, vset, exp, this);        if (right.type.inMask(TM_NUMBER)) {            type = right.type;        } else {            if (!right.type.isType(TC_ERROR)) {                env.error(where, "invalid.arg.type", right.type, opNames[op]);            }            type = Type.tError;        }        updater = right.getUpdater(env, ctx);  // Must be called after 'checkAssignOp'.        return vset;    }     /**     * Check void expression     */    public Vset check(Environment env, Context ctx, Vset vset, Hashtable exp) {        return checkValue(env, ctx, vset, exp);    }     /**     * Inline     */    public Expression inline(Environment env, Context ctx) {        return inlineValue(env, ctx);    }    public Expression inlineValue(Environment env, Context ctx) {        // Why not inlineLHS?  But that does not work.        right = right.inlineValue(env, ctx);        if (updater != null) {            updater = updater.inline(env, ctx);        }        return this;    }     public int costInline(int thresh, Environment env, Context ctx) {        if (updater == null) {            if ((right.op == IDENT) && type.isType(TC_INT) &&                (((IdentifierExpression)right).field.isLocal())) {                // Increment variable in place.  Count 3 bytes for 'iinc'.                return 3;            }            // Cost to load lhs reference, fetch local, increment, and store.            // Load/store cost will be higher if variable is a field.  Note that            // costs are highly approximate. See 'AssignOpExpression.costInline'            // Does not account for cost of conversions,or duplications in            // value-needed context..            return right.costInline(thresh, env, ctx) + 4;        } else {            // Cost of two access method calls (get/set) + cost of increment.            return updater.costInline(thresh, env, ctx, true) + 1;        }    }      /**     * Code     */     private void codeIncDecOp(Assembler asm, boolean inc) {        switch (type.getTypeCode()) {          case TC_BYTE:            asm.add(where, opc_ldc, new Integer(1));            asm.add(where, inc ? opc_iadd : opc_isub);            asm.add(where, opc_i2b);            break;          case TC_SHORT:            asm.add(where, opc_ldc, new Integer(1));            asm.add(where, inc ? opc_iadd : opc_isub);            asm.add(where, opc_i2s);            break;          case TC_CHAR:            asm.add(where, opc_ldc, new Integer(1));            asm.add(where, inc ? opc_iadd : opc_isub);            asm.add(where, opc_i2c);            break;          case TC_INT:            asm.add(where, opc_ldc, new Integer(1));            asm.add(where, inc ? opc_iadd : opc_isub);            break;          case TC_LONG:            asm.add(where, opc_ldc2_w, new Long(1));            asm.add(where, inc ? opc_ladd : opc_lsub);            break;          case TC_FLOAT:            asm.add(where, opc_ldc, new Float(1));            asm.add(where, inc ? opc_fadd : opc_fsub);            break;          case TC_DOUBLE:            asm.add(where, opc_ldc2_w, new Double(1));            asm.add(where, inc ? opc_dadd : opc_dsub);            break;          default:            throw new CompilerError("invalid type");        }    }     void codeIncDec(Environment env, Context ctx, Assembler asm, boolean inc, boolean prefix, boolean valNeeded) {         // The 'iinc' instruction cannot be used if an access method call is required.        if ((right.op == IDENT) && type.isType(TC_INT) &&            (((IdentifierExpression)right).field.isLocal()) && updater == null) {            if (valNeeded && !prefix) {                right.codeLoad(env, ctx, asm);            }            int v = ((LocalMember)((IdentifierExpression)right).field).number;            int[] operands = { v, inc ? 1 : -1 };            asm.add(where, opc_iinc, operands);            if (valNeeded && prefix) {                right.codeLoad(env, ctx, asm);            }            return;         }         if (updater == null) {            // Field is directly accessible.            int depth = right.codeLValue(env, ctx, asm);            codeDup(env, ctx, asm, depth, 0);            right.codeLoad(env, ctx, asm);            if (valNeeded && !prefix) {                codeDup(env, ctx, asm, type.stackSize(), depth);            }            codeIncDecOp(asm, inc);            if (valNeeded && prefix) {                codeDup(env, ctx, asm, type.stackSize(), depth);            }            right.codeStore(env, ctx, asm);        } else {            // Must use access methods.            updater.startUpdate(env, ctx, asm, (valNeeded && !prefix));            codeIncDecOp(asm, inc);            updater.finishUpdate(env, ctx, asm, (valNeeded && prefix));        }    } }