1 /*
2 * Copyright (c) 2000, 2008, 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.compiler;
26
27 import java.util.*;
28
29 import sun.jvm.hotspot.code.*;
30 import sun.jvm.hotspot.debugger.*;
31 import sun.jvm.hotspot.runtime.*;
32 import sun.jvm.hotspot.types.*;
33 import sun.jvm.hotspot.utilities.*;
34
35 public class OopMapSet extends VMObject {
36 private static final boolean DEBUG = System.getProperty("sun.jvm.hotspot.compiler.OopMapSet.DEBUG") != null;
37
38 private static CIntegerField omCountField;
39 private static CIntegerField omSizeField;
40 private static AddressField omDataField;
41 private static int REG_COUNT;
42 private static int SAVED_ON_ENTRY_REG_COUNT;
43 private static int C_SAVED_ON_ENTRY_REG_COUNT;
44 private static class MyVisitor implements OopMapVisitor {
45 private AddressVisitor addressVisitor;
46
47 public MyVisitor(AddressVisitor oopVisitor) {
48 setAddressVisitor(oopVisitor);
49 }
50
51 public void setAddressVisitor(AddressVisitor addressVisitor) {
52 this.addressVisitor = addressVisitor;
53 }
54
55 public void visitOopLocation(Address oopAddr) {
56 addressVisitor.visitAddress(oopAddr);
57 }
58
59 public void visitDerivedOopLocation(Address baseOopAddr, Address derivedOopAddr) {
60 if (VM.getVM().isClientCompiler()) {
61 Assert.that(false, "should not reach here");
62 } else if (VM.getVM().isServerCompiler() &&
63 VM.getVM().useDerivedPointerTable()) {
64 Assert.that(false, "FIXME: add derived pointer table");
65 }
66 }
67
68 public void visitValueLocation(Address valueAddr) {
69 }
70
71 public void visitNarrowOopLocation(Address narrowOopAddr) {
72 addressVisitor.visitCompOopAddress(narrowOopAddr);
73 }
74 }
75
76 static {
77 VM.registerVMInitializedObserver(new Observer() {
78 public void update(Observable o, Object data) {
79 initialize(VM.getVM().getTypeDataBase());
80 }
81 });
82 }
83
84 private static void initialize(TypeDataBase db) {
85 Type type = db.lookupType("OopMapSet");
86
87 omCountField = type.getCIntegerField("_om_count");
88 omSizeField = type.getCIntegerField("_om_size");
89 omDataField = type.getAddressField("_om_data");
90
91 if (!VM.getVM().isCore()) {
92 REG_COUNT = db.lookupIntConstant("REG_COUNT").intValue();
93 if (VM.getVM().isServerCompiler()) {
94 SAVED_ON_ENTRY_REG_COUNT = (int) db.lookupIntConstant("SAVED_ON_ENTRY_REG_COUNT").intValue();
95 C_SAVED_ON_ENTRY_REG_COUNT = (int) db.lookupIntConstant("C_SAVED_ON_ENTRY_REG_COUNT").intValue();
96 }
97 }
98 }
99
100 public OopMapSet(Address addr) {
101 super(addr);
102 }
103
104 /** Returns the number of OopMaps in this OopMapSet */
105 public long getSize() {
106 return omCountField.getValue(addr);
107 }
108
109 /** returns the OopMap at a given index */
110 public OopMap getMapAt(int index) {
111 if (Assert.ASSERTS_ENABLED) {
112 Assert.that((index >= 0) && (index <= getSize()),"bad index");
113 }
114 Address omDataAddr = omDataField.getValue(addr);
115 Address oopMapAddr = omDataAddr.getAddressAt(index * VM.getVM().getAddressSize());
116 if (oopMapAddr == null) {
117 return null;
118 }
119 return new OopMap(oopMapAddr);
120 }
121
122 public OopMap findMapAtOffset(long pcOffset, boolean debugging) {
123 int i;
124 int len = (int) getSize();
125 if (Assert.ASSERTS_ENABLED) {
126 Assert.that(len > 0, "must have pointer maps");
127 }
128
129 // Scan through oopmaps. Stop when current offset is either equal or greater
130 // than the one we are looking for.
131 for (i = 0; i < len; i++) {
132 if (getMapAt(i).getOffset() >= pcOffset) {
133 break;
134 }
135 }
136
137 if (!debugging) {
138 if (Assert.ASSERTS_ENABLED) {
139 Assert.that(i < len, "oopmap not found for pcOffset = " + pcOffset + "; len = " + len);
140 Assert.that(getMapAt(i).getOffset() == pcOffset, "oopmap not found");
141 }
142 } else {
143 if (i == len) {
144 if (DEBUG) {
145 System.out.println("can't find oopmap at " + pcOffset);
146 System.out.print("Oopmap offsets are [ ");
147 for (i = 0; i < len; i++) {
148 System.out.print(getMapAt(i).getOffset());
149 }
150 System.out.println("]");
151 }
152 i = len - 1;
153 return getMapAt(i);
154 }
155 }
156
157 OopMap m = getMapAt(i);
158 return m;
159 }
160
161 /** Visitation -- iterates through the frame for a compiled method.
162 This is a very generic mechanism that requires the Address to be
163 dereferenced by the callee. Other, more specialized, visitation
164 mechanisms are given below. */
165 public static void oopsDo(Frame fr, CodeBlob cb, RegisterMap regMap, AddressVisitor oopVisitor, boolean debugging) {
166 allDo(fr, cb, regMap, new MyVisitor(oopVisitor), debugging);
167 }
168
169 /** Note that there are 4 required AddressVisitors: one for oops,
170 one for derived oops, one for values, and one for dead values */
171 public static void allDo(Frame fr, CodeBlob cb, RegisterMap regMap, OopMapVisitor visitor, boolean debugging) {
172 if (Assert.ASSERTS_ENABLED) {
173 CodeBlob tmpCB = VM.getVM().getCodeCache().findBlob(fr.getPC());
174 Assert.that(tmpCB != null && cb.equals(tmpCB), "wrong codeblob passed in");
175 }
176
177 OopMapSet maps = cb.getOopMaps();
178 OopMap map = cb.getOopMapForReturnAddress(fr.getPC(), debugging);
179 if (Assert.ASSERTS_ENABLED) {
180 Assert.that(map != null, "no ptr map found");
181 }
182
183 // handle derived pointers first (otherwise base pointer may be
184 // changed before derived pointer offset has been collected)
185 OopMapValue omv;
186 {
187 for (OopMapStream oms = new OopMapStream(map, OopMapValue.OopTypes.DERIVED_OOP_VALUE); !oms.isDone(); oms.next()) {
188 if (VM.getVM().isClientCompiler()) {
189 Assert.that(false, "should not reach here");
190 }
191 omv = oms.getCurrent();
192 Address loc = fr.oopMapRegToLocation(omv.getReg(), regMap);
193 if (loc != null) {
194 Address baseLoc = fr.oopMapRegToLocation(omv.getContentReg(), regMap);
195 Address derivedLoc = loc;
196 visitor.visitDerivedOopLocation(baseLoc, derivedLoc);
197 }
198 }
199 }
200
201 // We want narow oop, value and oop oop_types
202 OopMapValue.OopTypes[] values = new OopMapValue.OopTypes[] {
203 OopMapValue.OopTypes.OOP_VALUE, OopMapValue.OopTypes.VALUE_VALUE, OopMapValue.OopTypes.NARROWOOP_VALUE
204 };
205
206 {
207 for (OopMapStream oms = new OopMapStream(map, values); !oms.isDone(); oms.next()) {
208 omv = oms.getCurrent();
209 Address loc = fr.oopMapRegToLocation(omv.getReg(), regMap);
210 if (loc != null) {
211 if (omv.getType() == OopMapValue.OopTypes.OOP_VALUE) {
212 // This assert commented out because this will be useful
213 // to detect in the debugging system
214 // assert(Universe::is_heap_or_null(*loc), "found non oop pointer");
215 visitor.visitOopLocation(loc);
216 } else if (omv.getType() == OopMapValue.OopTypes.VALUE_VALUE) {
217 visitor.visitValueLocation(loc);
218 } else if (omv.getType() == OopMapValue.OopTypes.NARROWOOP_VALUE) {
219 visitor.visitNarrowOopLocation(loc);
220 }
221 }
222 }
223 }
224 }
225
226 /** Update callee-saved register info for the following frame.
227 Should only be called in non-core builds. */
228 public static void updateRegisterMap(Frame fr, CodeBlob cb, RegisterMap regMap, boolean debugging) {
229 if (Assert.ASSERTS_ENABLED) {
230 Assert.that(!VM.getVM().isCore(), "non-core builds only");
231 }
232
233 if (!VM.getVM().isDebugging()) {
234 if (Assert.ASSERTS_ENABLED) {
235 OopMapSet maps = cb.getOopMaps();
236 Assert.that((maps != null) && (maps.getSize() > 0), "found null or empty OopMapSet for CodeBlob");
237 }
238 } else {
239 // Hack for some topmost frames that have been found with empty
240 // OopMapSets. (Actually have not seen the null case, but don't
241 // want to take any chances.) See HSDB.showThreadStackMemory().
242 OopMapSet maps = cb.getOopMaps();
243 if ((maps == null) || (maps.getSize() == 0)) {
244 return;
245 }
246 }
247
248 // Check if caller must update oop argument
249 regMap.setIncludeArgumentOops(cb.callerMustGCArguments());
250
251 int nofCallee = 0;
252 Address[] locs = new Address[2 * REG_COUNT + 1];
253 VMReg [] regs = new VMReg [2 * REG_COUNT + 1];
254 // ("+1" because REG_COUNT might be zero)
255
256 // Scan through oopmap and find location of all callee-saved registers
257 // (we do not do update in place, since info could be overwritten)
258 OopMap map = cb.getOopMapForReturnAddress(fr.getPC(), debugging);
259 if (Assert.ASSERTS_ENABLED) {
260 Assert.that(map != null, "no ptr map found");
261 }
262
263 OopMapValue omv = null;
264 for(OopMapStream oms = new OopMapStream(map, OopMapValue.OopTypes.CALLEE_SAVED_VALUE); !oms.isDone(); oms.next()) {
265 omv = oms.getCurrent();
266 if (Assert.ASSERTS_ENABLED) {
267 Assert.that(nofCallee < 2 * REG_COUNT, "overflow");
268 }
269 regs[nofCallee] = omv.getContentReg();
270 locs[nofCallee] = fr.oopMapRegToLocation(omv.getReg(), regMap);
271 nofCallee++;
272 }
273
274 // Check that runtime stubs save all callee-saved registers
275 // After adapter frames were deleted C2 doesn't use callee save registers at present
276 if (Assert.ASSERTS_ENABLED) {
277 if (VM.getVM().isServerCompiler()) {
278 Assert.that(!cb.isRuntimeStub() ||
279 (nofCallee >= SAVED_ON_ENTRY_REG_COUNT || nofCallee >= C_SAVED_ON_ENTRY_REG_COUNT),
280 "must save all");
281 }
282 }
283
284 // Copy found callee-saved register to reg_map
285 for (int i = 0; i < nofCallee; i++) {
286 regMap.setLocation(regs[i], locs[i]);
287 }
288 }
289 }