1 cananian 1.1.2.6 // ClazPointer.java, created Sat Mar 27 17:05:07 1999 by duncan
2 cananian 1.1.2.5 // Copyright (C) 1998 Duncan Bryce <duncan@lcs.mit.edu>
3 cananian 1.1.2.5 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 duncan 1.1.2.1 package harpoon.Interpret.Tree;
5 duncan 1.1.2.1
6 duncan 1.1.2.1 import harpoon.Util.Tuple;
7 duncan 1.1.2.1 import harpoon.Temp.Label;
8 duncan 1.1.2.1
9 duncan 1.1.2.1 /**
10 duncan 1.1.2.1 * The <code>ClazPointer</code> is used to representing a pointer
11 duncan 1.1.2.1 * to static class data.
12 duncan 1.1.2.1 *
13 duncan 1.1.2.1 * @author Duncan Bryce <duncan@lcs.mit.edu>
14 cananian 1.3 * @version $Id: ClazPointer.java,v 1.3 2002/04/10 03:05:56 cananian Exp $
15 duncan 1.1.2.1 */
16 duncan 1.1.2.1 class ClazPointer extends Pointer {
17 duncan 1.1.2.1 private boolean isDerived;
18 cananian 1.2.2.1 private final StaticState ss;
19 duncan 1.1.2.1
20 duncan 1.1.2.1 // Private constructor used to add two ClazPointers.
21 duncan 1.1.2.1 private ClazPointer(ClazPointer base, long offset) {
22 duncan 1.1.2.1 this((Label)base.getBase(), base.ss, base.getOffset() + offset, true);
23 duncan 1.1.2.1 }
24 duncan 1.1.2.1
25 duncan 1.1.2.1 // Private constructor used to clone a ClazPointer.
26 pnkfelix 1.1.2.2 private ClazPointer(Label base, final StaticState ss,
27 duncan 1.1.2.1 long offset, boolean isDerived) {
28 duncan 1.1.2.1 super(new Object[] { base, new Long(offset) });
29 duncan 1.1.2.1 this.ss = ss;
30 duncan 1.1.2.1 this.isDerived = isDerived;
31 duncan 1.1.2.1 }
32 duncan 1.1.2.1
33 duncan 1.1.2.1 /** Class constructor */
34 pnkfelix 1.1.2.2 ClazPointer(Label base, final StaticState ss, long offset) {
35 duncan 1.1.2.1 this(base, ss, offset, false);
36 duncan 1.1.2.1 }
37 duncan 1.1.2.1
38 duncan 1.1.2.1 /** Adds the specified parameter to this <code>ClazPointer</code>'s
39 duncan 1.1.2.1 * offset */
40 duncan 1.1.2.1 public Pointer add(long offset) {
41 duncan 1.1.2.1 return new ClazPointer(this, offset);
42 duncan 1.1.2.1 }
43 duncan 1.1.2.1
44 duncan 1.1.2.1 /** Returns true if <code>obj</code> is a <code>ClazPointer</code> which
45 duncan 1.1.2.1 * points to the same location as this <code>ClazPointer</code>.
46 duncan 1.1.2.1 */
47 duncan 1.1.2.1 public boolean equals(Object obj) {
48 cananian 1.1.2.3 ClazPointer ptr;
49 cananian 1.1.2.3 if (this==obj) return true;
50 cananian 1.1.2.3 if (null==obj) return false;
51 cananian 1.1.2.3 try { ptr = (ClazPointer)obj; }
52 cananian 1.1.2.3 catch (ClassCastException ignore) { return false; }
53 cananian 1.1.2.3 return (((Label)getBase()).toString().equals
54 cananian 1.1.2.3 (((Label)ptr.getBase()).toString())) &&
55 cananian 1.1.2.3 getOffset()==ptr.getOffset();
56 duncan 1.1.2.1 }
57 duncan 1.1.2.1
58 duncan 1.1.2.1 /** Returns a <code>Label</code> representing the base of this
59 duncan 1.1.2.1 * <code>ConstPointer</code>.
60 duncan 1.1.2.1 */
61 duncan 1.1.2.1 public Object getBase() { return (Label)proj(0); }
62 duncan 1.1.2.1
63 duncan 1.1.2.1 /** Returns the offset of this <code>ClazPointer</code>. */
64 duncan 1.1.2.1 public long getOffset() { return ((Long)proj(1)).longValue(); }
65 duncan 1.1.2.1
66 duncan 1.1.2.1 /** Dereferences this <code>ClazPointer</code> and returns the value
67 duncan 1.1.2.1 * it points to. */
68 duncan 1.1.2.1 public Object getValue() { return ss.getValue(this); }
69 duncan 1.1.2.1
70 duncan 1.1.2.1 /** Always returns false. */
71 duncan 1.1.2.1 public boolean isConst() { return false; }
72 duncan 1.1.2.1
73 duncan 1.1.2.1 /** Returns true if this <code>ClazPointer</code> has been derived from
74 duncan 1.1.2.1 * another <code>ClazPointer</code> */
75 duncan 1.1.2.1 public boolean isDerived() { return isDerived; }
76 duncan 1.1.2.4
77 duncan 1.1.2.4 /** Returns an integer enumeration of the kind of this Pointer. The
78 duncan 1.1.2.4 enumerated values are public fields of the Pointer class.
79 duncan 1.1.2.4 */
80 duncan 1.1.2.4 public int kind() { return Pointer.CLAZ_PTR; }
81 duncan 1.1.2.1
82 duncan 1.1.2.1 /** Throws an error, as the program is not supposed to
83 duncan 1.1.2.1 * modify static class data */
84 duncan 1.1.2.1 public void updateValue(Object obj) {
85 duncan 1.1.2.1 throw new Error("Can't modify claz data!");
86 duncan 1.1.2.1 }
87 duncan 1.1.2.1
88 duncan 1.1.2.1 /** Returns a human-readable representation of this
89 duncan 1.1.2.1 * <code>ClazPointer</code> */
90 duncan 1.1.2.1 public String toString() {
91 duncan 1.1.2.1 StringBuffer sb = new StringBuffer("ClazPtr: < ");
92 duncan 1.1.2.1 sb.append(getBase().toString());
93 duncan 1.1.2.1 sb.append(" , ");
94 duncan 1.1.2.1 sb.append(getOffset());
95 duncan 1.1.2.1 sb.append(" >");
96 duncan 1.1.2.1 return sb.toString();
97 duncan 1.1.2.1 }
98 duncan 1.1.2.1 }
99 duncan 1.1.2.1
100 duncan 1.1.2.1
101 duncan 1.1.2.1
102 duncan 1.1.2.1
103 cananian 1.2