1 /*
2 * Copyright (c) 2000, 2012, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 package sun.jvm.hotspot.code;
26
27 import java.util.*;
28 import sun.jvm.hotspot.debugger.*;
29 import sun.jvm.hotspot.memory.*;
30 import sun.jvm.hotspot.runtime.*;
31 import sun.jvm.hotspot.types.*;
32 import sun.jvm.hotspot.utilities.*;
33
34 public class CodeCache {
35 private static GrowableArray<CodeHeap> heapArray;
36 private static AddressField scavengeRootNMethodsField;
37 private static VirtualConstructor virtualConstructor;
38
39 static {
40 VM.registerVMInitializedObserver(new Observer() {
41 public void update(Observable o, Object data) {
42 initialize(VM.getVM().getTypeDataBase());
43 }
44 });
45 }
46
47 private static synchronized void initialize(TypeDataBase db) {
48 Type type = db.lookupType("CodeCache");
49
50 // Get array of CodeHeaps
51 AddressField heapsField = type.getAddressField("_heaps");
52 heapArray = GrowableArray.create(heapsField.getValue(), new StaticBaseConstructor<CodeHeap>(CodeHeap.class));
53
54 scavengeRootNMethodsField = type.getAddressField("_scavenge_root_nmethods");
55
56 virtualConstructor = new VirtualConstructor(db);
57 // Add mappings for all possible CodeBlob subclasses
58 virtualConstructor.addMapping("BufferBlob", BufferBlob.class);
59 virtualConstructor.addMapping("nmethod", NMethod.class);
60 virtualConstructor.addMapping("RuntimeStub", RuntimeStub.class);
61 virtualConstructor.addMapping("AdapterBlob", AdapterBlob.class);
62 virtualConstructor.addMapping("MethodHandlesAdapterBlob", MethodHandlesAdapterBlob.class);
63 virtualConstructor.addMapping("SafepointBlob", SafepointBlob.class);
64 virtualConstructor.addMapping("DeoptimizationBlob", DeoptimizationBlob.class);
65 if (VM.getVM().isServerCompiler()) {
66 virtualConstructor.addMapping("ExceptionBlob", ExceptionBlob.class);
67 virtualConstructor.addMapping("UncommonTrapBlob", UncommonTrapBlob.class);
68 }
69 }
70
71 public NMethod scavengeRootMethods() {
72 return (NMethod) VMObjectFactory.newObject(NMethod.class, scavengeRootNMethodsField.getValue());
73 }
74
75 public boolean contains(Address p) {
76 for (int i = 0; i < heapArray.length(); ++i) {
77 if (heapArray.at(i).contains(p)) {
78 return true;
79 }
80 }
81 return false;
82 }
83
84 /** When VM.getVM().isDebugging() returns true, this behaves like
85 findBlobUnsafe */
86 public CodeBlob findBlob(Address start) {
87 CodeBlob result = findBlobUnsafe(start);
88 if (result == null) return null;
89 if (VM.getVM().isDebugging()) {
90 return result;
91 }
92 // We could potientially look up non_entrant methods
93 // NOTE: this is effectively a "guarantee", and is slightly different from the one in the VM
94 if (Assert.ASSERTS_ENABLED) {
95 Assert.that(!(result.isZombie() || result.isLockedByVM()), "unsafe access to zombie method");
96 }
97 return result;
98 }
99
100 public CodeBlob findBlobUnsafe(Address start) {
101 CodeBlob result = null;
102 CodeHeap containing_heap = null;
103 for (int i = 0; i < heapArray.length(); ++i) {
104 if (heapArray.at(i).contains(start)) {
105 containing_heap = heapArray.at(i);
106 break;
107 }
108 }
109 if (containing_heap == null) {
110 return null;
111 }
112
113 try {
114 result = (CodeBlob) virtualConstructor.instantiateWrapperFor(containing_heap.findStart(start));
115 }
116 catch (WrongTypeException wte) {
117 Address cbAddr = null;
118 try {
119 cbAddr = containing_heap.findStart(start);
120 }
121 catch (Exception findEx) {
122 findEx.printStackTrace();
123 }
124
125 String message = "Couldn't deduce type of CodeBlob ";
126 if (cbAddr != null) {
127 message = message + "@" + cbAddr + " ";
128 }
129 message = message + "for PC=" + start;
130
131 throw new RuntimeException(message, wte);
132 }
133 if (result == null) return null;
134 if (Assert.ASSERTS_ENABLED) {
135 // The HeapBlock that contains this blob is outside of the blob
136 // but it shouldn't be an error to find a blob based on the
137 // pointer to the HeapBlock.
138 Assert.that(result.blobContains(start) || result.blobContains(start.addOffsetTo(8)),
139 "found wrong CodeBlob");
140 }
141 return result;
142 }
143
144 public NMethod findNMethod(Address start) {
145 CodeBlob cb = findBlob(start);
146 if (Assert.ASSERTS_ENABLED) {
147 Assert.that(cb == null || cb.isNMethod(), "did not find an nmethod");
148 }
149 return (NMethod) cb;
150 }
151
152 public NMethod findNMethodUnsafe(Address start) {
153 CodeBlob cb = findBlobUnsafe(start);
154 if (Assert.ASSERTS_ENABLED) {
155 Assert.that(cb == null || cb.isNMethod(), "did not find an nmethod");
156 }
157 return (NMethod) cb;
158 }
159
160 /** Routine for instantiating appropriately-typed wrapper for a
161 CodeBlob. Used by CodeCache, Runtime1, etc. */
162 public CodeBlob createCodeBlobWrapper(Address codeBlobAddr) {
163 try {
164 return (CodeBlob) virtualConstructor.instantiateWrapperFor(codeBlobAddr);
165 }
166 catch (Exception e) {
167 String message = "Unable to deduce type of CodeBlob from address " + codeBlobAddr +
168 " (expected type nmethod, RuntimeStub, ";
169 if (VM.getVM().isClientCompiler()) {
170 message = message + " or ";
171 }
172 message = message + "SafepointBlob";
173 if (VM.getVM().isServerCompiler()) {
174 message = message + ", DeoptimizationBlob, or ExceptionBlob";
175 }
176 message = message + ")";
177 throw new RuntimeException(message);
178 }
179 }
180
181 public void iterate(CodeCacheVisitor visitor) {
182 visitor.prologue(lowBound(), highBound());
183 CodeBlob lastBlob = null;
184
185 for (int i = 0; i < heapArray.length(); ++i) {
186 CodeHeap current_heap = heapArray.at(i);
187 Address ptr = current_heap.begin();
188 while (ptr != null && ptr.lessThan(current_heap.end())) {
189 try {
190 // Use findStart to get a pointer inside blob other findBlob asserts
191 CodeBlob blob = findBlobUnsafe(current_heap.findStart(ptr));
192 if (blob != null) {
193 visitor.visit(blob);
194 if (blob == lastBlob) {
195 throw new InternalError("saw same blob twice");
196 }
197 lastBlob = blob;
198 }
199 } catch (RuntimeException e) {
200 e.printStackTrace();
201 }
202 Address next = current_heap.nextBlock(ptr);
203 if (next != null && next.lessThan(ptr)) {
204 throw new InternalError("pointer moved backwards");
205 }
206 ptr = next;
207 }
208 }
209 visitor.epilogue();
210 }
211
212 //--------------------------------------------------------------------------------
213 // Internals only below this point
214 //
215
216 private Address lowBound() {
217 Address low = heapArray.at(0).begin();
218 for (int i = 1; i < heapArray.length(); ++i) {
219 if (heapArray.at(i).begin().lessThan(low)) {
220 low = heapArray.at(i).begin();
221 }
222 }
223 return low;
224 }
225
226 private Address highBound() {
227 Address high = heapArray.at(0).end();
228 for (int i = 1; i < heapArray.length(); ++i) {
229 if (heapArray.at(i).end().greaterThan(high)) {
230 high = heapArray.at(i).end();
231 }
232 }
233 return high;
234 }
235 }