1 cananian 1.1.2.5 // InlineMap.java, created Thu Jan 14 22:17:20 1999 by duncan
2 cananian 1.1.2.6 // Copyright (C) 1998 Duncan Bryce <duncan@lcs.mit.edu>
3 cananian 1.1.2.4 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 duncan 1.1.2.2 package harpoon.Backend.Maps;
5 duncan 1.1.2.1
6 duncan 1.1.2.1 import harpoon.ClassFile.HField;
7 duncan 1.1.2.1
8 duncan 1.1.2.1 /**
9 duncan 1.1.2.1 * An <code>InlineMap</code> maps an <code>HField</code> to a boolean value
10 cananian 1.1.2.3 * indicated whether the <code>HField</code> can be inlined.
11 cananian 1.1.2.3 * We leave the policy decision of whether it is wise to do so to other
12 cananian 1.1.2.3 * code, which will also be an InlineMap. So, the idea is that a core
13 cananian 1.1.2.3 * InlineMap implements the conservative analysis of inline-safety, then
14 cananian 1.1.2.3 * a second inline map takes the first inline map and twiddles the inlining
15 cananian 1.1.2.3 * results according to whether or not it thinks inlining is really a good
16 cananian 1.1.2.3 * idea, using some heuristic. Or you can leave out the second inline map
17 cananian 1.1.2.3 * and its heuristics, which just means you'd like to inline wherever
18 cananian 1.1.2.3 * possible. Have I confused everyone yet?
19 duncan 1.1.2.1 *
20 cananian 1.1.2.6 * @author Duncan Bryce <duncan@lcs.mit.edu>
21 cananian 1.2 * @version $Id: InlineMap.java,v 1.2 2002/02/25 21:01:59 cananian Exp $
22 duncan 1.1.2.1 */
23 cananian 1.1.2.3 public abstract class InlineMap // may need to be an interface later, but
24 cananian 1.1.2.3 // we'll try to keep it a class if we can.
25 duncan 1.1.2.1 {
26 duncan 1.1.2.1 /**
27 cananian 1.1.2.3 * @return <code>true</code> if the <code>HField</code> can be inlined
28 cananian 1.1.2.3 * using type 1 inlining (the class descriptor for the inlined object is
29 cananian 1.1.2.3 * preserved). This can be done even if the field escapes, as long as it
30 cananian 1.1.2.3 * is a final field.
31 duncan 1.1.2.1 */
32 cananian 1.1.2.3 public abstract boolean canInline1(HField hf);
33 cananian 1.1.2.3 /**
34 cananian 1.1.2.3 * @return <code>true</code> if the <code>HField</code> should be inlined
35 cananian 1.1.2.3 * using type 2 inlining (the class descriptor for the inlined object is
36 cananian 1.1.2.3 * omitted). This can only be done if the field doesn't escape.
37 cananian 1.1.2.3 * Returning <code>true</code> implies shouldInline1() returns
38 cananian 1.1.2.3 * <code>true</code>, too.
39 cananian 1.1.2.3 */
40 cananian 1.1.2.3 public abstract boolean canInline2(HField hf);
41 duncan 1.1.2.1 }
42 duncan 1.1.2.1
43 duncan 1.1.2.1
44 cananian 1.2