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