1 /*
2 * Copyright (c) 2000, 2010, 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.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 sun.jvm.hotspot.types.OopField methodField;
39 /** != InvocationEntryBci if this nmethod is an on-stack replacement method */
40 private static CIntegerField entryBCIField;
41 /** To support simple linked-list chaining of nmethods */
42 private static AddressField osrLinkField;
43 private static AddressField scavengeRootLinkField;
44 private static JByteField scavengeRootStateField;
45
46 /** Offsets for different nmethod parts */
47 private static CIntegerField exceptionOffsetField;
48 private static CIntegerField deoptOffsetField;
49 private static CIntegerField deoptMhOffsetField;
50 private static CIntegerField origPCOffsetField;
51 private static CIntegerField stubOffsetField;
52 private static CIntegerField oopsOffsetField;
53 private static CIntegerField scopesDataOffsetField;
54 private static CIntegerField scopesPCsOffsetField;
55 private static CIntegerField dependenciesOffsetField;
56 private static CIntegerField handlerTableOffsetField;
57 private static CIntegerField nulChkTableOffsetField;
58 private static CIntegerField nmethodEndOffsetField;
59
60 /** Offsets for entry points */
61 /** Entry point with class check */
62 private static AddressField entryPointField;
63 /** Entry point without class check */
64 private static AddressField verifiedEntryPointField;
65 /** Entry point for on stack replacement */
66 private static AddressField osrEntryPointField;
67
68 // FIXME: add access to flags (how?)
69
70 /** NMethod Flushing lock (if non-zero, then the nmethod is not removed) */
71 private static JIntField lockCountField;
72
73 /** not_entrant method removal. Each mark_sweep pass will update
74 this mark to current sweep invocation count if it is seen on the
75 stack. An not_entrant method can be removed when there is no
76 more activations, i.e., when the _stack_traversal_mark is less than
77 current sweep traversal index. */
78 private static CIntegerField stackTraversalMarkField;
79
80 static {
81 VM.registerVMInitializedObserver(new Observer() {
82 public void update(Observable o, Object data) {
83 initialize(VM.getVM().getTypeDataBase());
84 }
85 });
86 }
87
88 private static void initialize(TypeDataBase db) {
89 Type type = db.lookupType("nmethod");
90
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 deoptMhOffsetField = type.getCIntegerField("_deoptimize_mh_offset");
100 origPCOffsetField = type.getCIntegerField("_orig_pc_offset");
101 stubOffsetField = type.getCIntegerField("_stub_offset");
102 oopsOffsetField = type.getCIntegerField("_oops_offset");
103 scopesDataOffsetField = type.getCIntegerField("_scopes_data_offset");
104 scopesPCsOffsetField = type.getCIntegerField("_scopes_pcs_offset");
105 dependenciesOffsetField = type.getCIntegerField("_dependencies_offset");
106 handlerTableOffsetField = type.getCIntegerField("_handler_table_offset");
107 nulChkTableOffsetField = type.getCIntegerField("_nul_chk_table_offset");
108 nmethodEndOffsetField = type.getCIntegerField("_nmethod_end_offset");
109 entryPointField = type.getAddressField("_entry_point");
110 verifiedEntryPointField = type.getAddressField("_verified_entry_point");
111 osrEntryPointField = type.getAddressField("_osr_entry_point");
112 lockCountField = type.getJIntField("_lock_count");
113 stackTraversalMarkField = type.getCIntegerField("_stack_traversal_mark");
114
115 pcDescSize = db.lookupType("PcDesc").getSize();
116 }
117
118 public NMethod(Address addr) {
119 super(addr);
120 }
121
122
123 // Accessors
124 public Address getAddress() {
125 return addr;
126 }
127
128 public Method getMethod() {
129 return (Method) VM.getVM().getObjectHeap().newOop(methodField.getValue(addr));
130 }
131
132 // Type info
133 public boolean isNMethod() { return true; }
134 public boolean isJavaMethod() { return !getMethod().isNative(); }
135 public boolean isNativeMethod() { return getMethod().isNative(); }
136 public boolean isOSRMethod() { return getEntryBCI() != VM.getVM().getInvocationEntryBCI(); }
137
138 /** Boundaries for different parts */
139 public Address constantsBegin() { return contentBegin(); }
140 public Address constantsEnd() { return getEntryPoint(); }
141 public Address instsBegin() { return codeBegin(); }
142 public Address instsEnd() { return headerBegin().addOffsetTo(getStubOffset()); }
143 public Address exceptionBegin() { return headerBegin().addOffsetTo(getExceptionOffset()); }
144 public Address deoptHandlerBegin() { return headerBegin().addOffsetTo(getDeoptOffset()); }
145 public Address deoptMhHandlerBegin() { return headerBegin().addOffsetTo(getDeoptMhOffset()); }
146 public Address stubBegin() { return headerBegin().addOffsetTo(getStubOffset()); }
147 public Address stubEnd() { return headerBegin().addOffsetTo(getOopsOffset()); }
148 public Address oopsBegin() { return headerBegin().addOffsetTo(getOopsOffset()); }
149 public Address oopsEnd() { return headerBegin().addOffsetTo(getScopesDataOffset()); }
150 public Address scopesDataBegin() { return headerBegin().addOffsetTo(getScopesDataOffset()); }
151 public Address scopesDataEnd() { return headerBegin().addOffsetTo(getScopesPCsOffset()); }
152 public Address scopesPCsBegin() { return headerBegin().addOffsetTo(getScopesPCsOffset()); }
153 public Address scopesPCsEnd() { return headerBegin().addOffsetTo(getDependenciesOffset()); }
154 public Address dependenciesBegin() { return headerBegin().addOffsetTo(getDependenciesOffset()); }
155 public Address dependenciesEnd() { return headerBegin().addOffsetTo(getHandlerTableOffset()); }
156 public Address handlerTableBegin() { return headerBegin().addOffsetTo(getHandlerTableOffset()); }
157 public Address handlerTableEnd() { return headerBegin().addOffsetTo(getNulChkTableOffset()); }
158 public Address nulChkTableBegin() { return headerBegin().addOffsetTo(getNulChkTableOffset()); }
159 public Address nulChkTableEnd() { return headerBegin().addOffsetTo(getNMethodEndOffset()); }
160
161 public int constantsSize() { return (int) constantsEnd() .minus(constantsBegin()); }
162 public int instsSize() { return (int) instsEnd() .minus(instsBegin()); }
163 public int stubSize() { return (int) stubEnd() .minus(stubBegin()); }
164 public int oopsSize() { return (int) oopsEnd() .minus(oopsBegin()); }
165 public int scopesDataSize() { return (int) scopesDataEnd() .minus(scopesDataBegin()); }
166 public int scopesPCsSize() { return (int) scopesPCsEnd() .minus(scopesPCsBegin()); }
167 public int dependenciesSize() { return (int) dependenciesEnd().minus(dependenciesBegin()); }
168 public int handlerTableSize() { return (int) handlerTableEnd().minus(handlerTableBegin()); }
169 public int nulChkTableSize() { return (int) nulChkTableEnd() .minus(nulChkTableBegin()); }
170 public int origPCOffset() { return (int) origPCOffsetField.getValue(addr); }
171
172 public int totalSize() {
173 return
174 constantsSize() +
175 instsSize() +
176 stubSize() +
177 scopesDataSize() +
178 scopesPCsSize() +
179 dependenciesSize() +
180 handlerTableSize() +
181 nulChkTableSize();
182 }
183
184 public boolean constantsContains (Address addr) { return constantsBegin() .lessThanOrEqual(addr) && constantsEnd() .greaterThan(addr); }
185 public boolean instsContains (Address addr) { return instsBegin() .lessThanOrEqual(addr) && instsEnd() .greaterThan(addr); }
186 public boolean stubContains (Address addr) { return stubBegin() .lessThanOrEqual(addr) && stubEnd() .greaterThan(addr); }
187 public boolean oopsContains (Address addr) { return oopsBegin() .lessThanOrEqual(addr) && oopsEnd() .greaterThan(addr); }
188 public boolean scopesDataContains (Address addr) { return scopesDataBegin() .lessThanOrEqual(addr) && scopesDataEnd() .greaterThan(addr); }
189 public boolean scopesPCsContains (Address addr) { return scopesPCsBegin() .lessThanOrEqual(addr) && scopesPCsEnd() .greaterThan(addr); }
190 public boolean handlerTableContains(Address addr) { return handlerTableBegin().lessThanOrEqual(addr) && handlerTableEnd().greaterThan(addr); }
191 public boolean nulChkTableContains (Address addr) { return nulChkTableBegin() .lessThanOrEqual(addr) && nulChkTableEnd() .greaterThan(addr); }
192
193 /** Entry points */
194 public Address getEntryPoint() { return entryPointField.getValue(addr); }
195 public Address getVerifiedEntryPoint() { return verifiedEntryPointField.getValue(addr); }
196
197 /** Support for oops in scopes and relocs. Note: index 0 is reserved for null. */
198 public OopHandle getOopAt(int index) {
199 if (index == 0) return null;
200 if (Assert.ASSERTS_ENABLED) {
201 Assert.that(index > 0 && index <= oopsSize(), "must be a valid non-zero index");
202 }
203 return oopsBegin().getOopHandleAt((index - 1) * VM.getVM().getOopSize());
204 }
205
206 // FIXME: add interpreter_entry_point()
207 // FIXME: add lazy_interpreter_entry_point() for C2
208
209 // **********
210 // * FIXME: * ADD ACCESS TO FLAGS!!!!
211 // **********
212 // public boolean isInUse();
213 // public boolean isAlive();
214 // public boolean isNotEntrant();
215 // public boolean isZombie();
216
217 // ********************************
218 // * MAJOR FIXME: MAJOR HACK HERE *
219 // ********************************
220 public boolean isZombie() { return false; }
221
222 // public boolean isUnloaded();
223 // public boolean isYoung();
224 // public boolean isOld();
225 // public int age();
226 // public boolean isMarkedForDeoptimization();
227 // public boolean isMarkedForUnloading();
228 // public boolean isMarkedForReclamation();
229 // public int level();
230 // public int version();
231
232 // FIXME: add mutators for above
233 // FIXME: add exception cache access?
234
235 /** On-stack replacement support */
236 // FIXME: add mutators
237 public int getOSREntryBCI() {
238 if (Assert.ASSERTS_ENABLED) {
239 Assert.that(getEntryBCI() != VM.getVM().getInvocationEntryBCI(), "wrong kind of nmethod");
240 }
241 return getEntryBCI();
242 }
243
244 public NMethod getOSRLink() {
245 return (NMethod) VMObjectFactory.newObject(NMethod.class, osrLinkField.getValue(addr));
246 }
247
248 public NMethod getScavengeRootLink() {
249 return (NMethod) VMObjectFactory.newObject(NMethod.class, scavengeRootLinkField.getValue(addr));
250 }
251
252 public int getScavengeRootState() {
253 return (int) scavengeRootStateField.getValue(addr);
254 }
255
256 // MethodHandle
257 public boolean isMethodHandleReturn(Address returnPc) {
258 // Hard to read a bit fields from Java and it's only there for performance
259 // so just go directly to the PCDesc
260 // if (!hasMethodHandleInvokes()) return false;
261 PCDesc pd = getPCDescAt(returnPc);
262 if (pd == null)
263 return false;
264 return pd.isMethodHandleInvoke();
265 }
266
267 // Deopt
268 // Return true is the PC is one would expect if the frame is being deopted.
269 public boolean isDeoptPc (Address pc) { return isDeoptEntry(pc) || isDeoptMhEntry(pc); }
270 public boolean isDeoptEntry (Address pc) { return pc == deoptHandlerBegin(); }
271 public boolean isDeoptMhEntry (Address pc) { return pc == deoptMhHandlerBegin(); }
272
273 /** Tells whether frames described by this nmethod can be
274 deoptimized. Note: native wrappers cannot be deoptimized. */
275 public boolean canBeDeoptimized() { return isJavaMethod(); }
276
277 // FIXME: add inline cache support
278 // FIXME: add flush()
279
280 public boolean isLockedByVM() { return lockCountField.getValue(addr) > 0; }
281
282 // FIXME: add mark_as_seen_on_stack
283 // FIXME: add can_not_entrant_be_converted
284
285 // FIXME: add GC support
286 // void follow_roots_or_mark_for_unloading(bool unloading_occurred, bool& marked_for_unloading);
287 // void follow_root_or_mark_for_unloading(oop* root, bool unloading_occurred, bool& marked_for_unloading);
288 // void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, void f(oop*));
289 // void adjust_pointers();
290
291 /** Finds a PCDesc with real-pc equal to "pc" */
292 public PCDesc getPCDescAt(Address pc) {
293 // FIXME: consider adding cache like the one down in the VM
294 for (Address p = scopesPCsBegin(); p.lessThan(scopesPCsEnd()); p = p.addOffsetTo(pcDescSize)) {
295 PCDesc pcDesc = new PCDesc(p);
296 if (pcDesc.getRealPC(this).equals(pc)) {
297 return pcDesc;
298 }
299 }
300 return null;
301 }
302
303 /** ScopeDesc for an instruction */
304 public ScopeDesc getScopeDescAt(Address pc) {
305 PCDesc pd = getPCDescAt(pc);
306 if (Assert.ASSERTS_ENABLED) {
307 Assert.that(pd != null, "scope must be present");
308 }
309 return new ScopeDesc(this, pd.getScopeDecodeOffset(), pd.getObjDecodeOffset(), pd.getReexecute());
310 }
311
312 /** This is only for use by the debugging system, and is only
313 intended for use in the topmost frame, where we are not
314 guaranteed to be at a PC for which we have a PCDesc. It finds
315 the PCDesc with realPC closest to the current PC. */
316 public PCDesc getPCDescNearDbg(Address pc) {
317 PCDesc bestGuessPCDesc = null;
318 long bestDistance = 0;
319 for (Address p = scopesPCsBegin(); p.lessThan(scopesPCsEnd()); p = p.addOffsetTo(pcDescSize)) {
320 PCDesc pcDesc = new PCDesc(p);
321 // In case pc is null
322 long distance = -pcDesc.getRealPC(this).minus(pc);
323 if ((bestGuessPCDesc == null) ||
324 ((distance >= 0) && (distance < bestDistance))) {
325 bestGuessPCDesc = pcDesc;
326 bestDistance = distance;
327 }
328 }
329 return bestGuessPCDesc;
330 }
331
332 /** This is only for use by the debugging system, and is only
333 intended for use in the topmost frame, where we are not
334 guaranteed to be at a PC for which we have a PCDesc. It finds
335 the ScopeDesc closest to the current PC. NOTE that this may
336 return NULL for compiled methods which don't have any
337 ScopeDescs! */
338 public ScopeDesc getScopeDescNearDbg(Address pc) {
339 PCDesc pd = getPCDescNearDbg(pc);
340 if (pd == null) return null;
341 return new ScopeDesc(this, pd.getScopeDecodeOffset(), pd.getObjDecodeOffset(), pd.getReexecute());
342 }
343
344 public Map/*<Address, PCDesc>*/ getSafepoints() {
345 Map safepoints = new HashMap(); // Map<Address, PCDesc>
346 sun.jvm.hotspot.debugger.Address p = null;
347 for (p = scopesPCsBegin(); p.lessThan(scopesPCsEnd());
348 p = p.addOffsetTo(pcDescSize)) {
349 PCDesc pcDesc = new PCDesc(p);
350 sun.jvm.hotspot.debugger.Address pc = pcDesc.getRealPC(this);
351 safepoints.put(pc, pcDesc);
352 }
353 return safepoints;
354 }
355
356 // FIXME: add getPCOffsetForBCI()
357 // FIXME: add embeddedOopAt()
358 // FIXME: add isDependentOn()
359 // FIXME: add isPatchableAt()
360
361 /** Support for code generation. Only here for proof-of-concept. */
362 public static int getEntryPointOffset() { return (int) entryPointField.getOffset(); }
363 public static int getVerifiedEntryPointOffset() { return (int) verifiedEntryPointField.getOffset(); }
364 public static int getOSREntryPointOffset() { return (int) osrEntryPointField.getOffset(); }
365 public static int getEntryBCIOffset() { return (int) entryBCIField.getOffset(); }
366 /** NOTE: renamed from "method_offset_in_bytes" */
367 public static int getMethodOffset() { return (int) methodField.getOffset(); }
368
369 public void print() {
370 printOn(System.out);
371 }
372
373 protected void printComponentsOn(PrintStream tty) {
374 // FIXME: add relocation information
375 tty.println(" content: [" + contentBegin() + ", " + contentEnd() + "), " +
376 " code: [" + codeBegin() + ", " + codeEnd() + "), " +
377 " data: [" + dataBegin() + ", " + dataEnd() + "), " +
378 " oops: [" + oopsBegin() + ", " + oopsEnd() + "), " +
379 " frame size: " + getFrameSize());
380 }
381
382 public String toString() {
383 Method method = getMethod();
384 return "NMethod for " +
385 method.getMethodHolder().getName().asString() + "." +
386 method.getName().asString() + method.getSignature().asString() + "==>n" +
387 super.toString();
388 }
389
390 public String flagsToString() {
391 // FIXME need access to flags...
392 return "";
393 }
394
395 public String getName() {
396 Method method = getMethod();
397 return "NMethod for " +
398 method.getMethodHolder().getName().asString() + "." +
399 method.getName().asString() +
400 method.getSignature().asString();
401 }
402
403 //--------------------------------------------------------------------------------
404 // Internals only below this point
405 //
406
407 private int getEntryBCI() { return (int) entryBCIField .getValue(addr); }
408 private int getExceptionOffset() { return (int) exceptionOffsetField .getValue(addr); }
409 private int getDeoptOffset() { return (int) deoptOffsetField .getValue(addr); }
410 private int getDeoptMhOffset() { return (int) deoptMhOffsetField .getValue(addr); }
411 private int getStubOffset() { return (int) stubOffsetField .getValue(addr); }
412 private int getOopsOffset() { return (int) oopsOffsetField .getValue(addr); }
413 private int getScopesDataOffset() { return (int) scopesDataOffsetField .getValue(addr); }
414 private int getScopesPCsOffset() { return (int) scopesPCsOffsetField .getValue(addr); }
415 private int getDependenciesOffset() { return (int) dependenciesOffsetField.getValue(addr); }
416 private int getHandlerTableOffset() { return (int) handlerTableOffsetField.getValue(addr); }
417 private int getNulChkTableOffset() { return (int) nulChkTableOffsetField .getValue(addr); }
418 private int getNMethodEndOffset() { return (int) nmethodEndOffsetField .getValue(addr); }
419 }