1 /*
2 * Copyright 2000-2009 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 package sun.jvm.hotspot.code;
26
27 import java.io.*;
28 import java.util.*;
29 import sun.jvm.hotspot.debugger.*;
30 import sun.jvm.hotspot.memory.*;
31 import sun.jvm.hotspot.oops.*;
32 import sun.jvm.hotspot.runtime.*;
33 import sun.jvm.hotspot.types.*;
34 import sun.jvm.hotspot.utilities.*;
35
36 public class NMethod extends CodeBlob {
37 private static long pcDescSize;
38 private static CIntegerField zombieInstructionSizeField;
39 private static sun.jvm.hotspot.types.OopField methodField;
40 /** != InvocationEntryBci if this nmethod is an on-stack replacement method */
41 private static CIntegerField entryBCIField;
42 /** To support simple linked-list chaining of nmethods */
43 private static AddressField osrLinkField;
44 private static AddressField scavengeRootLinkField;
45 private static JByteField scavengeRootStateField;
46
47 /** Offsets for different nmethod parts */
48 private static CIntegerField exceptionOffsetField;
49 private static CIntegerField deoptOffsetField;
50 private static CIntegerField origPCOffsetField;
51 private static CIntegerField stubOffsetField;
52 private static CIntegerField scopesDataOffsetField;
53 private static CIntegerField scopesPCsOffsetField;
54 private static CIntegerField dependenciesOffsetField;
55 private static CIntegerField handlerTableOffsetField;
56 private static CIntegerField nulChkTableOffsetField;
57 private static CIntegerField nmethodEndOffsetField;
58
59 /** Offsets for entry points */
60 /** Entry point with class check */
61 private static AddressField entryPointField;
62 /** Entry point without class check */
63 private static AddressField verifiedEntryPointField;
64 /** Entry point for on stack replacement */
65 private static AddressField osrEntryPointField;
66
67 // FIXME: add access to flags (how?)
68
69 /** NMethod Flushing lock (if non-zero, then the nmethod is not removed) */
70 private static JIntField lockCountField;
71
72 /** not_entrant method removal. Each mark_sweep pass will update
73 this mark to current sweep invocation count if it is seen on the
74 stack. An not_entrant method can be removed when there is no
75 more activations, i.e., when the _stack_traversal_mark is less than
76 current sweep traversal index. */
77 private static CIntegerField stackTraversalMarkField;
78
79 static {
80 VM.registerVMInitializedObserver(new Observer() {
81 public void update(Observable o, Object data) {
82 initialize(VM.getVM().getTypeDataBase());
83 }
84 });
85 }
86
87 private static void initialize(TypeDataBase db) {
88 Type type = db.lookupType("nmethod");
89
90 zombieInstructionSizeField = type.getCIntegerField("_zombie_instruction_size");
91 methodField = type.getOopField("_method");
92 entryBCIField = type.getCIntegerField("_entry_bci");
93 osrLinkField = type.getAddressField("_osr_link");
94 scavengeRootLinkField = type.getAddressField("_scavenge_root_link");
95 scavengeRootStateField = type.getJByteField("_scavenge_root_state");
96
97 exceptionOffsetField = type.getCIntegerField("_exception_offset");
98 deoptOffsetField = type.getCIntegerField("_deoptimize_offset");
99 origPCOffsetField = type.getCIntegerField("_orig_pc_offset");
100 stubOffsetField = type.getCIntegerField("_stub_offset");
101 scopesDataOffsetField = type.getCIntegerField("_scopes_data_offset");
102 scopesPCsOffsetField = type.getCIntegerField("_scopes_pcs_offset");
103 dependenciesOffsetField = type.getCIntegerField("_dependencies_offset");
104 handlerTableOffsetField = type.getCIntegerField("_handler_table_offset");
105 nulChkTableOffsetField = type.getCIntegerField("_nul_chk_table_offset");
106 nmethodEndOffsetField = type.getCIntegerField("_nmethod_end_offset");
107 entryPointField = type.getAddressField("_entry_point");
108 verifiedEntryPointField = type.getAddressField("_verified_entry_point");
109 osrEntryPointField = type.getAddressField("_osr_entry_point");
110 lockCountField = type.getJIntField("_lock_count");
111 stackTraversalMarkField = type.getCIntegerField("_stack_traversal_mark");
112
113 pcDescSize = db.lookupType("PcDesc").getSize();
114 }
115
116 public NMethod(Address addr) {
117 super(addr);
118 }
119
120
121 // Accessors
122 public Address getAddress() {
123 return addr;
124 }
125
126 public Method getMethod() {
127 return (Method) VM.getVM().getObjectHeap().newOop(methodField.getValue(addr));
128 }
129
130 // Type info
131 public boolean isNMethod() { return true; }
132 public boolean isJavaMethod() { return !getMethod().isNative(); }
133 public boolean isNativeMethod() { return getMethod().isNative(); }
134 public boolean isOSRMethod() { return getEntryBCI() != VM.getVM().getInvocationEntryBCI(); }
135
136 /** Boundaries for different parts */
137 public Address constantsBegin() { return instructionsBegin(); }
138 public Address constantsEnd() { return getEntryPoint(); }
139 public Address codeBegin() { return getEntryPoint(); }
140 public Address codeEnd() { return headerBegin().addOffsetTo(getStubOffset()); }
141 public Address exceptionBegin() { return headerBegin().addOffsetTo(getExceptionOffset()); }
142 public Address deoptBegin() { return headerBegin().addOffsetTo(getDeoptOffset()); }
143 public Address stubBegin() { return headerBegin().addOffsetTo(getStubOffset()); }
144 public Address stubEnd() { return headerBegin().addOffsetTo(getScopesDataOffset()); }
145 public Address scopesDataBegin() { return headerBegin().addOffsetTo(getScopesDataOffset()); }
146 public Address scopesDataEnd() { return headerBegin().addOffsetTo(getScopesPCsOffset()); }
147 public Address scopesPCsBegin() { return headerBegin().addOffsetTo(getScopesPCsOffset()); }
148 public Address scopesPCsEnd() { return headerBegin().addOffsetTo(getDependenciesOffset()); }
149 public Address dependenciesBegin() { return headerBegin().addOffsetTo(getDependenciesOffset()); }
150 public Address dependenciesEnd() { return headerBegin().addOffsetTo(getHandlerTableOffset()); }
151 public Address handlerTableBegin() { return headerBegin().addOffsetTo(getHandlerTableOffset()); }
152 public Address handlerTableEnd() { return headerBegin().addOffsetTo(getNulChkTableOffset()); }
153 public Address nulChkTableBegin() { return headerBegin().addOffsetTo(getNulChkTableOffset()); }
154 public Address nulChkTableEnd() { return headerBegin().addOffsetTo(getNMethodEndOffset()); }
155
156 public int constantsSize() { return (int) constantsEnd() .minus(constantsBegin()); }
157 public int codeSize() { return (int) codeEnd() .minus(codeBegin()); }
158 public int stubSize() { return (int) stubEnd() .minus(stubBegin()); }
159 public int scopesDataSize() { return (int) scopesDataEnd() .minus(scopesDataBegin()); }
160 public int scopesPCsSize() { return (int) scopesPCsEnd() .minus(scopesPCsBegin()); }
161 public int dependenciesSize() { return (int) dependenciesEnd().minus(dependenciesBegin()); }
162 public int handlerTableSize() { return (int) handlerTableEnd().minus(handlerTableBegin()); }
163 public int nulChkTableSize() { return (int) nulChkTableEnd() .minus(nulChkTableBegin()); }
164 public int origPCOffset() { return (int) origPCOffsetField.getValue(addr); }
165
166 public int totalSize() {
167 return
168 constantsSize() +
169 codeSize() +
170 stubSize() +
171 scopesDataSize() +
172 scopesPCsSize() +
173 dependenciesSize() +
174 handlerTableSize() +
175 nulChkTableSize();
176 }
177
178 public boolean constantsContains (Address addr) { return constantsBegin() .lessThanOrEqual(addr) && constantsEnd() .greaterThan(addr); }
179 public boolean codeContains (Address addr) { return codeBegin() .lessThanOrEqual(addr) && codeEnd() .greaterThan(addr); }
180 public boolean stubContains (Address addr) { return stubBegin() .lessThanOrEqual(addr) && stubEnd() .greaterThan(addr); }
181 public boolean scopesDataContains (Address addr) { return scopesDataBegin() .lessThanOrEqual(addr) && scopesDataEnd() .greaterThan(addr); }
182 public boolean scopesPCsContains (Address addr) { return scopesPCsBegin() .lessThanOrEqual(addr) && scopesPCsEnd() .greaterThan(addr); }
183 public boolean handlerTableContains(Address addr) { return handlerTableBegin().lessThanOrEqual(addr) && handlerTableEnd().greaterThan(addr); }
184 public boolean nulChkTableContains (Address addr) { return nulChkTableBegin() .lessThanOrEqual(addr) && nulChkTableEnd() .greaterThan(addr); }
185
186 /** Entry points */
187 public Address getEntryPoint() { return entryPointField.getValue(addr); }
188 public Address getVerifiedEntryPoint() { return verifiedEntryPointField.getValue(addr); }
189
190 // FIXME: add interpreter_entry_point()
191 // FIXME: add lazy_interpreter_entry_point() for C2
192
193 // **********
194 // * FIXME: * ADD ACCESS TO FLAGS!!!!
195 // **********
196 // public boolean isInUse();
197 // public boolean isAlive();
198 // public boolean isNotEntrant();
199 // public boolean isZombie();
200
201 // ********************************
202 // * MAJOR FIXME: MAJOR HACK HERE *
203 // ********************************
204 public boolean isZombie() { return false; }
205
206 // public boolean isUnloaded();
207 // public boolean isYoung();
208 // public boolean isOld();
209 // public int age();
210 // public boolean isMarkedForDeoptimization();
211 // public boolean isMarkedForUnloading();
212 // public boolean isMarkedForReclamation();
213 // public int level();
214 // public int version();
215
216 // FIXME: add mutators for above
217 // FIXME: add exception cache access?
218
219 /** On-stack replacement support */
220 // FIXME: add mutators
221 public int getOSREntryBCI() {
222 if (Assert.ASSERTS_ENABLED) {
223 Assert.that(getEntryBCI() != VM.getVM().getInvocationEntryBCI(), "wrong kind of nmethod");
224 }
225 return getEntryBCI();
226 }
227
228 public NMethod getOSRLink() {
229 return (NMethod) VMObjectFactory.newObject(NMethod.class, osrLinkField.getValue(addr));
230 }
231
232 public NMethod getScavengeRootLink() {
233 return (NMethod) VMObjectFactory.newObject(NMethod.class, scavengeRootLinkField.getValue(addr));
234 }
235
236 public int getScavengeRootState() {
237 return (int) scavengeRootStateField.getValue(addr);
238 }
239
240
241 /** Tells whether frames described by this nmethod can be
242 deoptimized. Note: native wrappers cannot be deoptimized. */
243 public boolean canBeDeoptimized() { return isJavaMethod(); }
244
245 // FIXME: add inline cache support
246 // FIXME: add flush()
247
248 public boolean isLockedByVM() { return lockCountField.getValue(addr) > 0; }
249
250 // FIXME: add mark_as_seen_on_stack
251 // FIXME: add can_not_entrant_be_converted
252
253 // FIXME: add GC support
254 // void follow_roots_or_mark_for_unloading(bool unloading_occurred, bool& marked_for_unloading);
255 // void follow_root_or_mark_for_unloading(oop* root, bool unloading_occurred, bool& marked_for_unloading);
256 // void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, void f(oop*));
257 // void adjust_pointers();
258
259 /** Finds a PCDesc with real-pc equal to "pc" */
260 public PCDesc getPCDescAt(Address pc) {
261 // FIXME: consider adding cache like the one down in the VM
262 for (Address p = scopesPCsBegin(); p.lessThan(scopesPCsEnd()); p = p.addOffsetTo(pcDescSize)) {
263 PCDesc pcDesc = new PCDesc(p);
264 if (pcDesc.getRealPC(this).equals(pc)) {
265 return pcDesc;
266 }
267 }
268 return null;
269 }
270
271 /** ScopeDesc for an instruction */
272 public ScopeDesc getScopeDescAt(Address pc) {
273 PCDesc pd = getPCDescAt(pc);
274 if (Assert.ASSERTS_ENABLED) {
275 Assert.that(pd != null, "scope must be present");
276 }
277 return new ScopeDesc(this, pd.getScopeDecodeOffset(), pd.getObjDecodeOffset(), pd.getReexecute());
278 }
279
280 /** This is only for use by the debugging system, and is only
281 intended for use in the topmost frame, where we are not
282 guaranteed to be at a PC for which we have a PCDesc. It finds
283 the PCDesc with realPC closest to the current PC. */
284 public PCDesc getPCDescNearDbg(Address pc) {
285 PCDesc bestGuessPCDesc = null;
286 long bestDistance = 0;
287 for (Address p = scopesPCsBegin(); p.lessThan(scopesPCsEnd()); p = p.addOffsetTo(pcDescSize)) {
288 PCDesc pcDesc = new PCDesc(p);
289 // In case pc is null
290 long distance = -pcDesc.getRealPC(this).minus(pc);
291 if ((bestGuessPCDesc == null) ||
292 ((distance >= 0) && (distance < bestDistance))) {
293 bestGuessPCDesc = pcDesc;
294 bestDistance = distance;
295 }
296 }
297 return bestGuessPCDesc;
298 }
299
300 /** This is only for use by the debugging system, and is only
301 intended for use in the topmost frame, where we are not
302 guaranteed to be at a PC for which we have a PCDesc. It finds
303 the ScopeDesc closest to the current PC. NOTE that this may
304 return NULL for compiled methods which don't have any
305 ScopeDescs! */
306 public ScopeDesc getScopeDescNearDbg(Address pc) {
307 PCDesc pd = getPCDescNearDbg(pc);
308 if (pd == null) return null;
309 return new ScopeDesc(this, pd.getScopeDecodeOffset(), pd.getObjDecodeOffset(), pd.getReexecute());
310 }
311
312 public Map/*<Address, PCDesc>*/ getSafepoints() {
313 Map safepoints = new HashMap(); // Map<Address, PCDesc>
314 sun.jvm.hotspot.debugger.Address p = null;
315 for (p = scopesPCsBegin(); p.lessThan(scopesPCsEnd());
316 p = p.addOffsetTo(pcDescSize)) {
317 PCDesc pcDesc = new PCDesc(p);
318 sun.jvm.hotspot.debugger.Address pc = pcDesc.getRealPC(this);
319 safepoints.put(pc, pcDesc);
320 }
321 return safepoints;
322 }
323
324 // FIXME: add getPCOffsetForBCI()
325 // FIXME: add embeddedOopAt()
326 // FIXME: add isDependentOn()
327 // FIXME: add isPatchableAt()
328
329 /** Support for code generation. Only here for proof-of-concept. */
330 public static int getEntryPointOffset() { return (int) entryPointField.getOffset(); }
331 public static int getVerifiedEntryPointOffset() { return (int) verifiedEntryPointField.getOffset(); }
332 public static int getOSREntryPointOffset() { return (int) osrEntryPointField.getOffset(); }
333 public static int getEntryBCIOffset() { return (int) entryBCIField.getOffset(); }
334 /** NOTE: renamed from "method_offset_in_bytes" */
335 public static int getMethodOffset() { return (int) methodField.getOffset(); }
336
337 public void print() {
338 printOn(System.out);
339 }
340
341 public String toString() {
342 Method method = getMethod();
343 return "NMethod for " +
344 method.getMethodHolder().getName().asString() + "." +
345 method.getName().asString() + method.getSignature().asString() + "==>n" +
346 super.toString();
347 }
348
349 public String flagsToString() {
350 // FIXME need access to flags...
351 return "";
352 }
353
354 public String getName() {
355 Method method = getMethod();
356 return "NMethod for " +
357 method.getMethodHolder().getName().asString() + "." +
358 method.getName().asString() +
359 method.getSignature().asString();
360 }
361
362 //--------------------------------------------------------------------------------
363 // Internals only below this point
364 //
365
366 private int getEntryBCI() { return (int) entryBCIField .getValue(addr); }
367 private int getExceptionOffset() { return (int) exceptionOffsetField .getValue(addr); }
368 private int getDeoptOffset() { return (int) deoptOffsetField .getValue(addr); }
369 private int getStubOffset() { return (int) stubOffsetField .getValue(addr); }
370 private int getScopesDataOffset() { return (int) scopesDataOffsetField .getValue(addr); }
371 private int getScopesPCsOffset() { return (int) scopesPCsOffsetField .getValue(addr); }
372 private int getDependenciesOffset() { return (int) dependenciesOffsetField.getValue(addr); }
373 private int getHandlerTableOffset() { return (int) handlerTableOffsetField.getValue(addr); }
374 private int getNulChkTableOffset() { return (int) nulChkTableOffsetField .getValue(addr); }
375 private int getNMethodEndOffset() { return (int) nmethodEndOffsetField .getValue(addr); }
376 }