1 kkz 1.1.2.1 // WriteBarrierPrePass.java, created Mon Aug 13 18:29:34 2001 by kkz
2 kkz 1.1.2.1 // Copyright (C) 2000 Karen Zee <kkz@tmi.lcs.mit.edu>
3 kkz 1.1.2.1 // Licensed under the terms of the GNU GPL; see COPYING for details.
4 kkz 1.1.2.1 package harpoon.Analysis.PreciseGC;
5 kkz 1.1.2.1
6 kkz 1.1.2.1 import harpoon.Backend.Generic.Frame;
7 kkz 1.1.2.1 import harpoon.ClassFile.HClass;
8 kkz 1.1.2.1 import harpoon.ClassFile.HCode;
9 kkz 1.1.2.1 import harpoon.ClassFile.HCodeFactory;
10 kkz 1.1.2.1 import harpoon.ClassFile.HCodeAndMaps;
11 kkz 1.1.2.1 import harpoon.ClassFile.HMethod;
12 kkz 1.1.2.1 import harpoon.ClassFile.Linker;
13 kkz 1.1.2.1 import harpoon.IR.LowQuad.DerivationMap;
14 kkz 1.1.2.1 import harpoon.IR.LowQuad.LowQuadFactory;
15 kkz 1.1.2.1 import harpoon.IR.LowQuad.LowQuadVisitor;
16 kkz 1.1.2.1 import harpoon.IR.LowQuad.PCALL;
17 kkz 1.1.2.1 import harpoon.IR.LowQuad.PMCONST;
18 kkz 1.1.2.1 import harpoon.IR.LowQuad.PSET;
19 kkz 1.1.2.1 import harpoon.IR.Quads.Code;
20 kkz 1.1.2.1 import harpoon.IR.Quads.Edge;
21 kkz 1.1.2.1 import harpoon.IR.Quads.FOOTER;
22 kkz 1.1.2.1 import harpoon.IR.Quads.GET;
23 kkz 1.1.2.1 import harpoon.IR.Quads.HEADER;
24 kkz 1.1.2.1 import harpoon.IR.Quads.Quad;
25 kkz 1.1.2.1 import harpoon.IR.Quads.QuadFactory;
26 kkz 1.1.2.1 import harpoon.IR.Quads.THROW;
27 kkz 1.1.2.2 import harpoon.IR.Quads.Code;
28 kkz 1.1.2.1 import harpoon.Temp.Temp;
29 kkz 1.1.2.1 import harpoon.Temp.TempFactory;
30 kkz 1.1.2.1
31 kkz 1.1.2.1
32 kkz 1.1.2.1 /**
33 kkz 1.1.2.1 * <code>WriteBarrierPrePass</code> takes code in LowQuad form and
34 kkz 1.1.2.1 * inserts a fake call to a write barrier that is later replaced with
35 kkz 1.1.2.1 * a real implementation in <code>WriteBarrierPostPass</code>.
36 kkz 1.1.2.1 *
37 kkz 1.1.2.1 * @author Karen Zee <kkz@tmi.lcs.mit.edu>
38 cananian 1.2 * @version $Id: WriteBarrierPrePass.java,v 1.2 2002/02/25 20:58:54 cananian Exp $
39 kkz 1.1.2.1 */
40 kkz 1.1.2.1 public class WriteBarrierPrePass extends
41 kkz 1.1.2.1 harpoon.Analysis.Transformation.MethodMutator {
42 kkz 1.1.2.1
43 kkz 1.1.2.1 final private HMethod dummyHM;
44 kkz 1.1.2.1 final private HClass JLT;
45 kkz 1.1.2.1
46 kkz 1.1.2.1 /** Creates a <code>WriteBarrierPrePass</code>. */
47 kkz 1.1.2.1 public WriteBarrierPrePass(HCodeFactory parent, Linker linker) {
48 kkz 1.1.2.1 super(parent);
49 kkz 1.1.2.1 this.JLT = linker.forName("java.lang.Throwable");
50 kkz 1.1.2.1 HClass WB = linker.forName("harpoon.Runtime.PreciseGC.WriteBarrier");
51 kkz 1.1.2.1 HClass JLO = linker.forName("java.lang.Object");
52 kkz 1.1.2.1 this.dummyHM = WB.getMethod("storeCheck", new HClass[] { JLO });
53 kkz 1.1.2.1 }
54 kkz 1.1.2.1
55 kkz 1.1.2.1 protected HCode mutateHCode(HCodeAndMaps input) {
56 kkz 1.1.2.1 Code hc = (harpoon.IR.Quads.Code)input.hcode();
57 kkz 1.1.2.1 //hc.print(new java.io.PrintWriter(System.out), null);
58 kkz 1.1.2.1 HEADER header = (HEADER) hc.getRootElement();
59 kkz 1.1.2.1 FOOTER footer = (FOOTER) header.footer();
60 kkz 1.1.2.1 LowQuadVisitor qv = new WriteBarrierVisitor
61 kkz 1.1.2.2 ((DerivationMap)hc.getDerivation(), JLT, dummyHM, footer);
62 kkz 1.1.2.1 // we put all elements in array to avoid screwing up the
63 kkz 1.1.2.1 // iterator as we mutate the quad graph in-place.
64 kkz 1.1.2.1 Quad[] allquads = (Quad[]) hc.getElements();
65 kkz 1.1.2.1 for (int i=0; i<allquads.length; i++)
66 kkz 1.1.2.1 allquads[i].accept(qv);
67 kkz 1.1.2.1 // yay, done!
68 kkz 1.1.2.1 //hc.print(new java.io.PrintWriter(System.out), null);
69 kkz 1.1.2.1 return hc;
70 kkz 1.1.2.1 }
71 kkz 1.1.2.1
72 kkz 1.1.2.1 /** Return an <code>HCodeFactory</code> that will clean up the
73 kkz 1.1.2.1 * tree form of the transformed code by performing some optimizations
74 kkz 1.1.2.1 * which can't be represented in quad form. */
75 kkz 1.1.2.1 public HCodeFactory treeCodeFactory(Frame f, HCodeFactory hcf) {
76 kkz 1.1.2.1 return new WriteBarrierPostPass(f, dummyHM).codeFactory(hcf);
77 kkz 1.1.2.1 }
78 kkz 1.1.2.1
79 kkz 1.1.2.1
80 kkz 1.1.2.1 private static class WriteBarrierVisitor extends LowQuadVisitor {
81 kkz 1.1.2.1 final DerivationMap dm;
82 kkz 1.1.2.1 final HClass JLT;
83 kkz 1.1.2.1 final HMethod dummyHM;
84 kkz 1.1.2.1 FOOTER footer;
85 kkz 1.1.2.2 WriteBarrierVisitor(DerivationMap dm, HClass JLT, HMethod dummyHM,
86 kkz 1.1.2.2 FOOTER footer) {
87 kkz 1.1.2.1 this.dm = dm;
88 kkz 1.1.2.1 this.JLT = JLT;
89 kkz 1.1.2.1 this.dummyHM = dummyHM;
90 kkz 1.1.2.1 this.footer = footer;
91 kkz 1.1.2.1 }
92 kkz 1.1.2.1 public void visit(Quad q) { /* do nothing */ }
93 kkz 1.1.2.1 public void visit(PSET q) {
94 kkz 1.1.2.1 if (!q.type().isPrimitive()) {
95 kkz 1.1.2.1 LowQuadFactory qf = (LowQuadFactory)q.getFactory();
96 kkz 1.1.2.1 TempFactory tf = qf.tempFactory();
97 kkz 1.1.2.1 // create needed Temps
98 kkz 1.1.2.1 Temp func = new Temp(tf, "wb");
99 kkz 1.1.2.1 Temp retex = new Temp(tf, "wbex");
100 kkz 1.1.2.1 // create needed LowQuads
101 kkz 1.1.2.1 PMCONST pmconst = new PMCONST(qf, q, func, dummyHM);
102 kkz 1.1.2.1 PCALL pcall = new PCALL(qf, q, func,
103 kkz 1.1.2.1 new Temp[] { q.ptr() }, null, retex,
104 kkz 1.1.2.1 new Temp[0], false, false);
105 kkz 1.1.2.1 THROW thr = new THROW(qf, q, retex);
106 kkz 1.1.2.1 // update derivation information
107 kkz 1.1.2.1 dm.putType(pmconst, func, HClass.Void);
108 kkz 1.1.2.1 dm.putType(pcall, retex, JLT);
109 kkz 1.1.2.1 // add PMCONST and PCALL before PSET
110 kkz 1.1.2.1 splice(pmconst, q.prevEdge(0));
111 kkz 1.1.2.1 splice(pcall, q.prevEdge(0));
112 kkz 1.1.2.1 // add THROW after PCALL
113 kkz 1.1.2.1 Quad.addEdge(pcall, 1, thr, 0);
114 kkz 1.1.2.1 footer = footer.attach(thr, 0);
115 kkz 1.1.2.1 }
116 kkz 1.1.2.1 }
117 kkz 1.1.2.1 /** inserts the given Quad on the given Edge */
118 kkz 1.1.2.1 private void splice(Quad q, Edge e) {
119 kkz 1.1.2.1 Quad.addEdge((Quad)e.from(), e.which_succ(), q, 0);
120 kkz 1.1.2.1 Quad.addEdge(q, 0, (Quad)e.to(), e.which_pred());
121 kkz 1.1.2.1 }
122 kkz 1.1.2.1 }
123 cananian 1.2 }