1 /*
2  * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 only, as
7  * published by the Free Software Foundation.
8  *
9  * This code is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
15  * You should have received a copy of the GNU General Public License version
16  * 2 along with this work; if not, write to the Free Software Foundation,
17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20  * or visit www.oracle.com if you need additional information or have any
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22  *
23  */
24 
25 package sun.jvm.hotspot.interpreter;
26 
27 import sun.jvm.hotspot.oops.*;
28 import sun.jvm.hotspot.utilities.*;
29 
30 public class BytecodeLoad extends BytecodeLoadStore {
BytecodeLoad(Method method, int bci)31   BytecodeLoad(Method method, int bci) {
32     super(method, bci);
33   }
34 
verify()35   public void verify() {
36     if (Assert.ASSERTS_ENABLED) {
37       Assert.that(isValid(), "check load");
38     }
39   }
40 
isValid()41   public boolean isValid() {
42     int jcode = javaCode();
43     switch (jcode) {
44        case Bytecodes._iload:
45        case Bytecodes._lload:
46        case Bytecodes._fload:
47        case Bytecodes._dload:
48        case Bytecodes._aload:
49           return true;
50        default:
51           return false;
52     }
53   }
54 
at(Method method, int bci)55   public static BytecodeLoad at(Method method, int bci) {
56     BytecodeLoad b = new BytecodeLoad(method, bci);
57     if (Assert.ASSERTS_ENABLED) {
58       b.verify();
59     }
60     return b;
61   }
62 
63   /** Like at, but returns null if the BCI is not at load  */
atCheck(Method method, int bci)64   public static BytecodeLoad atCheck(Method method, int bci) {
65     BytecodeLoad b = new BytecodeLoad(method, bci);
66     return (b.isValid() ? b : null);
67   }
68 
at(BytecodeStream bcs)69   public static BytecodeLoad at(BytecodeStream bcs) {
70     return new BytecodeLoad(bcs.method(), bcs.bci());
71   }
72 }
73