1 cananian 1.1.2.1 // RuntimeMethodCloner.java, created Thu Nov 1 17:45:29 2001 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.Counters;
5 cananian 1.1.2.1
6 cananian 1.1.2.1 import harpoon.Analysis.Transformation.MethodMutator;
7 cananian 1.1.2.1 import harpoon.ClassFile.HClass;
8 cananian 1.1.2.1 import harpoon.ClassFile.HClassMutator;
9 cananian 1.1.2.1 import harpoon.ClassFile.HCode;
10 cananian 1.1.2.1 import harpoon.ClassFile.HCodeAndMaps;
11 cananian 1.1.2.1 import harpoon.ClassFile.HCodeElement;
12 cananian 1.1.2.1 import harpoon.ClassFile.HCodeFactory;
13 cananian 1.1.2.1 import harpoon.ClassFile.HMethod;
14 cananian 1.1.2.1 import harpoon.ClassFile.HMethodMutator;
15 cananian 1.1.2.1 import harpoon.ClassFile.Linker;
16 cananian 1.1.2.1 import harpoon.IR.Quads.CALL;
17 cananian 1.1.2.3 import harpoon.IR.Quads.CJMP;
18 cananian 1.1.2.3 import harpoon.IR.Quads.CONST;
19 cananian 1.1.2.3 import harpoon.IR.Quads.Edge;
20 cananian 1.1.2.3 import harpoon.IR.Quads.HEADER;
21 cananian 1.1.2.3 import harpoon.IR.Quads.METHOD;
22 cananian 1.1.2.3 import harpoon.IR.Quads.OPER;
23 cananian 1.1.2.3 import harpoon.IR.Quads.PHI;
24 cananian 1.1.2.3 import harpoon.IR.Quads.Qop;
25 cananian 1.1.2.1 import harpoon.IR.Quads.Quad;
26 cananian 1.1.2.3 import harpoon.IR.Quads.QuadFactory;
27 cananian 1.1.2.3 import harpoon.IR.Quads.QuadSSI;
28 cananian 1.1.2.3 import harpoon.Temp.Temp;
29 cananian 1.6 import net.cscott.jutil.GenericInvertibleMultiMap;
30 cananian 1.6 import net.cscott.jutil.InvertibleMultiMap;
31 cananian 1.6 import net.cscott.jutil.SnapshotIterator;
32 cananian 1.1.2.3 import harpoon.Util.Util;
33 cananian 1.1.2.1
34 cananian 1.1.2.1 import java.lang.reflect.Modifier;
35 cananian 1.1.2.1 import java.util.HashSet;
36 cananian 1.5 import java.util.Iterator;
37 cananian 1.1.2.1 import java.util.Map;
38 cananian 1.1.2.1 import java.util.Set;
39 cananian 1.1.2.1
40 cananian 1.1.2.1 /**
41 cananian 1.1.2.1 * <code>RuntimeMethodCloner</code> creates 'shadow' copies of all
42 cananian 1.1.2.1 * non-virtual methods called in <code>harpoon.Runtime.Counters</code>
43 cananian 1.1.2.1 * and places them in the <code>Counters</code> class. That way, we
44 cananian 1.1.2.1 * can easily *not* add statistics to stuff in
45 cananian 1.1.2.1 * <code>harpoon.Runtime.Counters</code> to avoid modifying the
46 cananian 1.1.2.1 * statistics as we're attempting to report them.
47 cananian 1.1.2.1 *
48 cananian 1.1.2.1 * @author C. Scott Ananian <cananian@alumni.princeton.edu>
49 cananian 1.6 * @version $Id: RuntimeMethodCloner.java,v 1.6 2004/02/08 01:51:01 cananian Exp $
50 cananian 1.1.2.1 */
51 cananian 1.5 public class RuntimeMethodCloner extends MethodMutator<Quad> {
52 cananian 1.1.2.1 private static final String classname = "harpoon.Runtime.Counters";
53 cananian 1.1.2.1 // map old method names to the new methods they now will be.
54 cananian 1.5 final Map<HMethod,HMethod> old2new;
55 cananian 1.1.2.1 // methods we'd like to relocate but can't.
56 cananian 1.5 final Set<HMethod> badboys = new HashSet<HMethod>();
57 cananian 1.1.2.1 // the linker.
58 cananian 1.1.2.1 final Linker linker;
59 cananian 1.1.2.3 // methods to add a null-check on 'this' to.
60 cananian 1.5 final Set<HMethod> needsNullCheck = new HashSet<HMethod>();
61 cananian 1.1.2.1
62 cananian 1.1.2.1 /** Creates a <code>RuntimeMethodCloner</code>. */
63 cananian 1.1.2.1 public RuntimeMethodCloner(final HCodeFactory parent, Linker linker) {
64 cananian 1.5 this(parent, linker, new GenericInvertibleMultiMap<HMethod,HMethod>());
65 cananian 1.1.2.1 }
66 cananian 1.1.2.1 private RuntimeMethodCloner(final HCodeFactory parent, Linker linker,
67 cananian 1.1.2.1 // i'd like new2old to be an InvertibleMap,
68 cananian 1.1.2.1 // but the type declarations aren't cooperating
69 cananian 1.5 final InvertibleMultiMap<HMethod,HMethod> new2old) {
70 cananian 1.1.2.1 super(new HCodeFactory() {
71 cananian 1.1.2.1 public void clear(HMethod m) { parent.clear(m); }
72 cananian 1.1.2.1 public String getCodeName() { return parent.getCodeName(); }
73 cananian 1.1.2.1 public HCode convert(HMethod m) {
74 cananian 1.1.2.1 if (!new2old.containsKey(m))
75 cananian 1.1.2.1 return parent.convert(m);
76 cananian 1.1.2.1 // this is a new one for us.
77 cananian 1.5 HMethod old = new2old.get(m);
78 cananian 1.1.2.1 HCode hc = convert(old);
79 cananian 1.1.2.1 try {
80 cananian 1.1.2.1 return hc.clone(m).hcode();
81 cananian 1.1.2.1 } catch (CloneNotSupportedException ex) {
82 cananian 1.1.2.1 // XXX: we don't allow this.
83 cananian 1.1.2.1 throw new RuntimeException(ex.toString());
84 cananian 1.1.2.1 }
85 cananian 1.1.2.1 }
86 cananian 1.1.2.1 });
87 cananian 1.1.2.1 this.linker = linker;
88 cananian 1.1.2.1 this.old2new = new2old.invert();
89 cananian 1.1.2.1 }
90 cananian 1.5 protected HCode<Quad> mutateHCode(HCodeAndMaps<Quad> input) {
91 cananian 1.5 HCode<Quad> hc = input.hcode();
92 cananian 1.1.2.1 // unless this belongs to harpoon.Runtime.Counters, we ignore it.
93 cananian 1.1.2.1 if (!hc.getMethod().getDeclaringClass().getName().equals(classname))
94 cananian 1.1.2.1 return hc;
95 cananian 1.1.2.1 // otherwise, we look for appropriate calls and rewrite them.
96 cananian 1.5 for (Iterator<Quad> it=new SnapshotIterator<Quad>(hc.getElementsI());
97 cananian 1.5 it.hasNext(); ) {
98 cananian 1.5 Quad q = it.next();
99 cananian 1.5 if (q instanceof CALL) {
100 cananian 1.5 CALL call = (CALL) q;
101 cananian 1.1.2.1 // do we want to relocate calls to this method?
102 cananian 1.1.2.1 if (!shouldRelocate(call.method()))
103 cananian 1.1.2.1 continue;
104 cananian 1.1.2.1 // can we? [we will complain about virtual calls]
105 cananian 1.1.2.1 // (note that Nonvirtualize is not invoked on methods
106 cananian 1.1.2.1 // in the Counters class, so we have to do our own
107 cananian 1.1.2.1 // final method nonvirtualization.)
108 cananian 1.1.2.1 if (call.isVirtual() && !isFinal(call.method())) {
109 cananian 1.1.2.1 if (!badboys.contains(call.method()))
110 cananian 1.1.2.1 System.err.println("WARNING: can't relocate "+
111 cananian 1.1.2.1 call.method()+" at "+
112 cananian 1.1.2.2 hc.getMethod()+" "+
113 cananian 1.1.2.1 call.getSourceFile()+":"+
114 cananian 1.1.2.1 call.getLineNumber());
115 cananian 1.1.2.1 badboys.add(call.method());
116 cananian 1.1.2.1 continue;
117 cananian 1.1.2.1 }
118 cananian 1.1.2.1 // okay, relocate this one.
119 cananian 1.1.2.1 HMethod nm = makeNewMethod(call.method());
120 cananian 1.1.2.1 Quad.replace(call, new CALL(call.getFactory(), call, nm,
121 cananian 1.1.2.1 call.params(), call.retval(),
122 cananian 1.1.2.1 call.retex(), false/*non-virtual*/,
123 cananian 1.1.2.1 call.isTailCall(),
124 cananian 1.1.2.1 call.dst(), call.src()));
125 cananian 1.1.2.1 // whoo-hoo! on to the next!
126 cananian 1.1.2.1 }
127 cananian 1.5 }
128 cananian 1.1.2.3 // when we relocate a method here, we make it static. that
129 cananian 1.1.2.3 // means that analyses can't automatically determine that the
130 cananian 1.1.2.3 // 'this' pointer is non-null. Insert an explicit test to
131 cananian 1.1.2.3 // inform these methods what's what.
132 cananian 1.1.2.3 if (needsNullCheck.contains(hc.getMethod())) {
133 cananian 1.3.2.1 assert !hc.getName().equals(QuadSSI.codename);
134 cananian 1.1.2.3 HEADER header = (HEADER) hc.getRootElement();
135 cananian 1.1.2.3 METHOD method = header.method();
136 cananian 1.1.2.3 QuadFactory qf = method.getFactory();
137 cananian 1.1.2.3 Temp nulT = new Temp(qf.tempFactory(), "nullconst");
138 cananian 1.1.2.3 Temp chkT = new Temp(qf.tempFactory(), "nullcheck");
139 cananian 1.1.2.3 Quad q0 = new CONST(qf, method, nulT, null, HClass.Void);
140 cananian 1.1.2.3 Quad q1 = new OPER(qf, method, Qop.ACMPEQ, chkT,
141 cananian 1.1.2.3 new Temp[] { nulT, method.params(0) });
142 cananian 1.1.2.3 Quad q2 = new CJMP(qf, method, chkT, new Temp[0]);
143 cananian 1.1.2.3 Quad q3 = new PHI(qf, method, new Temp[0], 2);
144 cananian 1.1.2.3 Edge e = method.nextEdge(0);
145 cananian 1.5 Quad.addEdge(e.from(), e.which_succ(), q0, 0);
146 cananian 1.1.2.3 Quad.addEdges(new Quad[] { q0, q1, q2 });
147 cananian 1.5 Quad.addEdge(q2, 0, e.to(), e.which_pred());
148 cananian 1.1.2.3 Quad.addEdge(q2, 1, q3, 0);
149 cananian 1.1.2.3 Quad.addEdge(q3, 0, q3, 1);
150 cananian 1.1.2.3 // not in SSI form. (in valid SSA/RSSx/NoSSx form, though).
151 cananian 1.1.2.3 }
152 cananian 1.1.2.1 // done!
153 cananian 1.1.2.1 return hc;
154 cananian 1.1.2.1 }
155 cananian 1.1.2.1 // check whether method or class is final.
156 cananian 1.1.2.1 private static boolean isFinal(HMethod hm) {
157 cananian 1.1.2.1 return Modifier.isFinal(hm.getModifiers()) ||
158 cananian 1.1.2.1 Modifier.isFinal(hm.getDeclaringClass().getModifiers());
159 cananian 1.1.2.1 }
160 cananian 1.1.2.1 // a variety of empirical criterial for relocating a method.
161 cananian 1.1.2.1 private boolean shouldRelocate(HMethod hm) {
162 cananian 1.1.2.1 // don't relocate ourselves!
163 cananian 1.1.2.1 if (hm.getDeclaringClass().getName().equals(classname))
164 cananian 1.1.2.1 return false;
165 cananian 1.1.2.1 // native methods are safe to skip.
166 cananian 1.1.2.1 if (Modifier.isNative(hm.getModifiers())) return false;
167 cananian 1.1.2.1 // let's assume exceptions never occur.
168 cananian 1.1.2.1 if (hm.getDeclaringClass().isInstanceOf
169 cananian 1.1.2.1 (linker.forName("java.lang.Throwable"))) return false;
170 cananian 1.1.2.1 // okay, we'll relocate everything else.
171 cananian 1.1.2.1 return true;
172 cananian 1.1.2.1 }
173 cananian 1.1.2.1 // create new method of harpoon.Runtime.Counters for given method.
174 cananian 1.1.2.1 private HMethod makeNewMethod(HMethod hm) {
175 cananian 1.1.2.1 if (!old2new.containsKey(hm)) {
176 cananian 1.1.2.1 HClass hc = linker.forName(classname);
177 cananian 1.1.2.1 // come up w/ uniq name for new method.
178 cananian 1.1.2.1 String name = "XXX."+
179 cananian 1.1.2.1 hm.getDeclaringClass().getName()+".."+hm.getName();
180 cananian 1.1.2.1 name = replace(name, "_", "_1");
181 cananian 1.1.2.1 name = replace(name, ".", "_");
182 cananian 1.1.2.1 // come up with new descriptor.
183 cananian 1.1.2.1 String desc = hm.getDescriptor();
184 cananian 1.1.2.1 if (!hm.isStatic()) {
185 cananian 1.1.2.1 // descriptor for original declaring class.
186 cananian 1.1.2.1 String newpart = hm.getDeclaringClass().getDescriptor();
187 cananian 1.1.2.1 // insert it after open paren.
188 cananian 1.1.2.1 desc = replace(desc, "(", "("+newpart);
189 cananian 1.1.2.1 }
190 cananian 1.1.2.1 // create method.
191 cananian 1.1.2.1 HMethod newm = hc.getMutator().addDeclaredMethod(name, desc);
192 cananian 1.1.2.1 // make it static (and public, just for kicks)
193 cananian 1.1.2.1 newm.getMutator().addModifiers(Modifier.STATIC|Modifier.PUBLIC);
194 cananian 1.1.2.3 // methods we've just made static need null-checks added on 'this'
195 cananian 1.1.2.3 if (!hm.isStatic()) needsNullCheck.add(newm);
196 cananian 1.1.2.1 // done! add it to the cache.
197 cananian 1.1.2.1 old2new.put(hm, newm);
198 cananian 1.1.2.1 }
199 cananian 1.5 return old2new.get(hm);
200 cananian 1.1.2.1 }
201 cananian 1.1.2.1 private static String replace(String s, String oldstr, String newstr) {
202 cananian 1.1.2.1 StringBuffer sb = new StringBuffer();
203 cananian 1.1.2.1 while (true) {
204 cananian 1.1.2.1 // find oldstr
205 cananian 1.1.2.1 int idx = s.indexOf(oldstr);
206 cananian 1.1.2.1 // if not found, then done.
207 cananian 1.1.2.1 if (idx<0) break;
208 cananian 1.1.2.1 // split at idx
209 cananian 1.1.2.1 sb.append(s.substring(0, idx));
210 cananian 1.1.2.1 s = s.substring(idx+oldstr.length());
211 cananian 1.1.2.1 // add newstr.
212 cananian 1.1.2.1 sb.append(newstr);
213 cananian 1.1.2.1 }
214 cananian 1.1.2.1 sb.append(s);
215 cananian 1.1.2.1 return sb.toString();
216 cananian 1.1.2.1 }
217 cananian 1.1.2.1 }
218 cananian 1.2