| /* |
| * 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.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 AssignExpression extends BinaryAssignExpression { |
| |
| private FieldUpdater updater = null; |
| |
| /** |
| * Constructor |
| */ |
| public AssignExpression(long where, Expression left, Expression right) { |
| super(ASSIGN, where, left, right); |
| } |
| |
| /** |
| * Check an assignment expression |
| */ |
| public Vset checkValue(Environment env, Context ctx, Vset vset, Hashtable<Object, Object> exp) { |
| if (left instanceof IdentifierExpression) { |
| // we don't want to mark an identifier as having a value |
| // until having evaluated the right-hand side |
| vset = right.checkValue(env, ctx, vset, exp); |
| vset = left.checkLHS(env, ctx, vset, exp); |
| } else { |
| // normally left to right evaluation. |
| vset = left.checkLHS(env, ctx, vset, exp); |
| vset = right.checkValue(env, ctx, vset, exp); |
| } |
| type = left.type; |
| right = convert(env, ctx, type, right); |
| |
| // Get field updater (access method) if needed, else null. |
| updater = left.getAssigner(env, ctx); |
| |
| return vset; |
| } |
| |
| /** |
| * Inline |
| */ |
| public Expression inlineValue(Environment env, Context ctx) { |
| if (implementation != null) |
| return implementation.inlineValue(env, ctx); |
| // Must be 'inlineLHS' here. But compare with similar case in |
| // 'AssignOpExpression' and 'IncDecExpression', which needs 'inlineValue'. |
| left = left.inlineLHS(env, ctx); |
| right = right.inlineValue(env, ctx); |
| if (updater != null) { |
| updater = updater.inline(env, ctx); |
| } |
| return this; |
| } |
| |
| /** |
| * Create a copy of the expression for method inlining |
| */ |
| public Expression copyInline(Context ctx) { |
| if (implementation != null) |
| return implementation.copyInline(ctx); |
| AssignExpression e = (AssignExpression)clone(); |
| e.left = left.copyInline(ctx); |
| e.right = right.copyInline(ctx); |
| if (updater != null) { |
| e.updater = updater.copyInline(ctx); |
| } |
| return e; |
| } |
| |
| /** |
| * The cost of inlining this expression |
| */ |
| public int costInline(int thresh, Environment env, Context ctx) { |
| /*----------* |
| return 2 + super.costInline(thresh, env, ctx); |
| *----------*/ |
| return (updater != null) |
| // Cost of rhs expression + cost of access method call. |
| // Access method call cost includes lhs cost. |
| ? right.costInline(thresh, env, ctx) + |
| updater.costInline(thresh, env, ctx, false) |
| // Cost of rhs expression + cost of lhs expression + |
| // cost of store instruction. |
| : right.costInline(thresh, env, ctx) + |
| left.costInline(thresh, env, ctx) + 2; |
| } |
| |
| /** |
| * Code |
| */ |
| public void codeValue(Environment env, Context ctx, Assembler asm) { |
| if (updater == null) { |
| // Field is directly accessible. |
| int depth = left.codeLValue(env, ctx, asm); |
| right.codeValue(env, ctx, asm); |
| codeDup(env, ctx, asm, right.type.stackSize(), depth); |
| left.codeStore(env, ctx, asm); |
| } else { |
| // Must use access method. |
| // Left operand is always a 'FieldExpression', or |
| // is rewritten as one via 'implementation'. |
| updater.startAssign(env, ctx, asm); |
| right.codeValue(env, ctx, asm); |
| updater.finishAssign(env, ctx, asm, true); |
| } |
| } |
| |
| public void code(Environment env, Context ctx, Assembler asm) { |
| if (updater == null) { |
| // Field is directly accessible. |
| left.codeLValue(env, ctx, asm); |
| right.codeValue(env, ctx, asm); |
| left.codeStore(env, ctx, asm); |
| } else { |
| // Must use access method. |
| // Left operand is always a 'FieldExpression', or |
| // is rewritten as one via 'implementation'. |
| updater.startAssign(env, ctx, asm); |
| right.codeValue(env, ctx, asm); |
| updater.finishAssign(env, ctx, asm, false); |
| } |
| } |
| } |