1 cananian 1.1.2.1 // SSXReachingDefsImpl.java, created Tue Jun 6 22:28:11 2000 by cananian
2 cananian 1.1.2.1 // Copyright (C) 2000 C. Scott Ananian <cananian@alumni.princeton.edu>
3 cananian 1.1.2.1 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 cananian 1.1.2.1 package harpoon.Analysis;
5 cananian 1.1.2.1
6 cananian 1.1.2.1 import harpoon.ClassFile.HCode;
7 cananian 1.1.2.1 import harpoon.ClassFile.HCodeElement;
8 cananian 1.1.2.1 import harpoon.IR.Properties.UseDefer;
9 cananian 1.1.2.1 import harpoon.Temp.Temp;
10 cananian 1.1.2.1 import harpoon.Util.Util;
11 cananian 1.1.2.1
12 cananian 1.1.2.1 import java.util.Collections;
13 cananian 1.1.2.1 import java.util.HashMap;
14 cananian 1.1.2.1 import java.util.Iterator;
15 cananian 1.1.2.1 import java.util.Map;
16 cananian 1.1.2.1 import java.util.Set;
17 cananian 1.1.2.1 /**
18 cananian 1.1.2.1 * <code>SSxReachingDefsImpl</code> is a <code>ReachingDefs</code>
19 cananian 1.1.2.1 * implementation that works on codeviews in SSA or SSI form. It
20 cananian 1.1.2.1 * is much more efficient (because of the SSx form) than the
21 cananian 1.1.2.1 * standard <code>ReachingDefsImpl</code>.
22 cananian 1.1.2.1 *
23 cananian 1.1.2.1 * @author C. Scott Ananian <cananian@alumni.princeton.edu>
24 cananian 1.6 * @version $Id: SSxReachingDefsImpl.java,v 1.6 2004/02/08 03:19:12 cananian Exp $
25 cananian 1.1.2.1 */
26 cananian 1.3.2.2 public class SSxReachingDefsImpl<HCE extends HCodeElement>
27 cananian 1.3.2.2 extends ReachingDefs<HCE> {
28 cananian 1.3.2.2 private final Map<Temp,HCE> m = new HashMap<Temp,HCE>();
29 cananian 1.1.2.1 /** Create an <code>SSxReachingDefs</code> using the default
30 cananian 1.1.2.1 * <code>UseDefer</code>. */
31 cananian 1.3.2.2 public SSxReachingDefsImpl(HCode<HCE> hc) {
32 cananian 1.5 this(hc, (UseDefer<HCE>) UseDefer.DEFAULT);
33 cananian 1.3.2.2 }
34 cananian 1.1.2.1 /** Create an <code>SSxReachingDefs</code> for <code>hc</code>
35 cananian 1.1.2.1 * using the specified <code>UseDefer</code>. */
36 cananian 1.3.2.2 public SSxReachingDefsImpl(HCode<HCE> hc, UseDefer<HCE> ud) {
37 cananian 1.1.2.1 super(hc);
38 cananian 1.3.2.2 for (Iterator<HCE> it = hc.getElementsI(); it.hasNext(); ) {
39 cananian 1.3.2.2 HCE hce = (HCE) it.next();
40 cananian 1.6 for (Temp t : ud.defC(hce)) {
41 cananian 1.3.2.1 assert !m.containsKey(t) : "not in SSA/SSI form!";
42 cananian 1.1.2.1 m.put(t, hce);
43 cananian 1.1.2.1 }
44 cananian 1.1.2.1 }
45 cananian 1.1.2.1 }
46 cananian 1.3.2.2 public Set<HCE> reachingDefs(HCE hce, Temp t) {
47 cananian 1.1.2.2 if (!m.containsKey(t)) return Collections.EMPTY_SET;
48 cananian 1.1.2.1 return Collections.singleton(m.get(t));
49 cananian 1.1.2.1 }
50 cananian 1.2 }