Mon, 07 Jul 2014 10:12:40 +0200
8049421: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com
1 /*
2 * Copyright (c) 1999, 2013, 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 */
25 #ifndef SHARE_VM_CI_CIENV_HPP
26 #define SHARE_VM_CI_CIENV_HPP
28 #include "ci/ciClassList.hpp"
29 #include "ci/ciObjectFactory.hpp"
30 #include "classfile/systemDictionary.hpp"
31 #include "code/debugInfoRec.hpp"
32 #include "code/dependencies.hpp"
33 #include "code/exceptionHandlerTable.hpp"
34 #include "compiler/oopMap.hpp"
35 #include "runtime/thread.hpp"
37 class CompileTask;
39 // ciEnv
40 //
41 // This class is the top level broker for requests from the compiler
42 // to the VM.
43 class ciEnv : StackObj {
44 CI_PACKAGE_ACCESS_TO
46 friend class CompileBroker;
47 friend class Dependencies; // for get_object, during logging
49 private:
50 Arena* _arena; // Alias for _ciEnv_arena except in init_shared_objects()
51 Arena _ciEnv_arena;
52 int _system_dictionary_modification_counter;
53 ciObjectFactory* _factory;
54 OopRecorder* _oop_recorder;
55 DebugInformationRecorder* _debug_info;
56 Dependencies* _dependencies;
57 const char* _failure_reason;
58 int _compilable;
59 bool _break_at_compile;
60 int _num_inlined_bytecodes;
61 CompileTask* _task; // faster access to CompilerThread::task
62 CompileLog* _log; // faster access to CompilerThread::log
63 void* _compiler_data; // compiler-specific stuff, if any
65 char* _name_buffer;
66 int _name_buffer_len;
68 // Cache Jvmti state
69 bool _jvmti_can_hotswap_or_post_breakpoint;
70 bool _jvmti_can_access_local_variables;
71 bool _jvmti_can_post_on_exceptions;
73 // Cache DTrace flags
74 bool _dtrace_extended_probes;
75 bool _dtrace_monitor_probes;
76 bool _dtrace_method_probes;
77 bool _dtrace_alloc_probes;
79 // Distinguished instances of certain ciObjects..
80 static ciObject* _null_object_instance;
82 #define WK_KLASS_DECL(name, ignore_s, ignore_o) static ciInstanceKlass* _##name;
83 WK_KLASSES_DO(WK_KLASS_DECL)
84 #undef WK_KLASS_DECL
86 static ciSymbol* _unloaded_cisymbol;
87 static ciInstanceKlass* _unloaded_ciinstance_klass;
88 static ciObjArrayKlass* _unloaded_ciobjarrayklass;
90 static jobject _ArrayIndexOutOfBoundsException_handle;
91 static jobject _ArrayStoreException_handle;
92 static jobject _ClassCastException_handle;
94 ciInstance* _NullPointerException_instance;
95 ciInstance* _ArithmeticException_instance;
96 ciInstance* _ArrayIndexOutOfBoundsException_instance;
97 ciInstance* _ArrayStoreException_instance;
98 ciInstance* _ClassCastException_instance;
100 ciInstance* _the_null_string; // The Java string "null"
101 ciInstance* _the_min_jint_string; // The Java string "-2147483648"
103 // Look up a klass by name from a particular class loader (the accessor's).
104 // If require_local, result must be defined in that class loader, or NULL.
105 // If !require_local, a result from remote class loader may be reported,
106 // if sufficient class loader constraints exist such that initiating
107 // a class loading request from the given loader is bound to return
108 // the class defined in the remote loader (or throw an error).
109 //
110 // Return an unloaded klass if !require_local and no class at all is found.
111 //
112 // The CI treats a klass as loaded if it is consistently defined in
113 // another loader, even if it hasn't yet been loaded in all loaders
114 // that could potentially see it via delegation.
115 ciKlass* get_klass_by_name(ciKlass* accessing_klass,
116 ciSymbol* klass_name,
117 bool require_local);
119 // Constant pool access.
120 ciKlass* get_klass_by_index(constantPoolHandle cpool,
121 int klass_index,
122 bool& is_accessible,
123 ciInstanceKlass* loading_klass);
124 ciConstant get_constant_by_index(constantPoolHandle cpool,
125 int pool_index, int cache_index,
126 ciInstanceKlass* accessor);
127 ciField* get_field_by_index(ciInstanceKlass* loading_klass,
128 int field_index);
129 ciMethod* get_method_by_index(constantPoolHandle cpool,
130 int method_index, Bytecodes::Code bc,
131 ciInstanceKlass* loading_klass);
133 // Implementation methods for loading and constant pool access.
134 ciKlass* get_klass_by_name_impl(ciKlass* accessing_klass,
135 constantPoolHandle cpool,
136 ciSymbol* klass_name,
137 bool require_local);
138 ciKlass* get_klass_by_index_impl(constantPoolHandle cpool,
139 int klass_index,
140 bool& is_accessible,
141 ciInstanceKlass* loading_klass);
142 ciConstant get_constant_by_index_impl(constantPoolHandle cpool,
143 int pool_index, int cache_index,
144 ciInstanceKlass* loading_klass);
145 ciField* get_field_by_index_impl(ciInstanceKlass* loading_klass,
146 int field_index);
147 ciMethod* get_method_by_index_impl(constantPoolHandle cpool,
148 int method_index, Bytecodes::Code bc,
149 ciInstanceKlass* loading_klass);
151 // Helper methods
152 bool check_klass_accessibility(ciKlass* accessing_klass,
153 Klass* resolved_klass);
154 Method* lookup_method(InstanceKlass* accessor,
155 InstanceKlass* holder,
156 Symbol* name,
157 Symbol* sig,
158 Bytecodes::Code bc);
160 // Get a ciObject from the object factory. Ensures uniqueness
161 // of ciObjects.
162 ciObject* get_object(oop o) {
163 if (o == NULL) {
164 return _null_object_instance;
165 } else {
166 return _factory->get(o);
167 }
168 }
170 ciSymbol* get_symbol(Symbol* o) {
171 if (o == NULL) {
172 ShouldNotReachHere();
173 return NULL;
174 } else {
175 return _factory->get_symbol(o);
176 }
177 }
179 ciMetadata* get_metadata(Metadata* o) {
180 if (o == NULL) {
181 return NULL;
182 } else {
183 return _factory->get_metadata(o);
184 }
185 }
187 void ensure_metadata_alive(ciMetadata* m) {
188 _factory->ensure_metadata_alive(m);
189 }
191 ciInstance* get_instance(oop o) {
192 if (o == NULL) return NULL;
193 return get_object(o)->as_instance();
194 }
195 ciObjArrayKlass* get_obj_array_klass(Klass* o) {
196 if (o == NULL) return NULL;
197 return get_metadata(o)->as_obj_array_klass();
198 }
199 ciTypeArrayKlass* get_type_array_klass(Klass* o) {
200 if (o == NULL) return NULL;
201 return get_metadata(o)->as_type_array_klass();
202 }
203 ciKlass* get_klass(Klass* o) {
204 if (o == NULL) return NULL;
205 return get_metadata(o)->as_klass();
206 }
207 ciInstanceKlass* get_instance_klass(Klass* o) {
208 if (o == NULL) return NULL;
209 return get_metadata(o)->as_instance_klass();
210 }
211 ciMethod* get_method(Method* o) {
212 if (o == NULL) return NULL;
213 return get_metadata(o)->as_method();
214 }
215 ciMethodData* get_method_data(MethodData* o) {
216 if (o == NULL) return NULL;
217 return get_metadata(o)->as_method_data();
218 }
220 ciMethod* get_method_from_handle(Method* method);
222 ciInstance* get_or_create_exception(jobject& handle, Symbol* name);
224 // Get a ciMethod representing either an unfound method or
225 // a method with an unloaded holder. Ensures uniqueness of
226 // the result.
227 ciMethod* get_unloaded_method(ciInstanceKlass* holder,
228 ciSymbol* name,
229 ciSymbol* signature,
230 ciInstanceKlass* accessor) {
231 return _factory->get_unloaded_method(holder, name, signature, accessor);
232 }
234 // Get a ciKlass representing an unloaded klass.
235 // Ensures uniqueness of the result.
236 ciKlass* get_unloaded_klass(ciKlass* accessing_klass,
237 ciSymbol* name) {
238 return _factory->get_unloaded_klass(accessing_klass, name, true);
239 }
241 // Get a ciKlass representing an unloaded klass mirror.
242 // Result is not necessarily unique, but will be unloaded.
243 ciInstance* get_unloaded_klass_mirror(ciKlass* type) {
244 return _factory->get_unloaded_klass_mirror(type);
245 }
247 // Get a ciInstance representing an unresolved method handle constant.
248 ciInstance* get_unloaded_method_handle_constant(ciKlass* holder,
249 ciSymbol* name,
250 ciSymbol* signature,
251 int ref_kind) {
252 return _factory->get_unloaded_method_handle_constant(holder, name, signature, ref_kind);
253 }
255 // Get a ciInstance representing an unresolved method type constant.
256 ciInstance* get_unloaded_method_type_constant(ciSymbol* signature) {
257 return _factory->get_unloaded_method_type_constant(signature);
258 }
260 // See if we already have an unloaded klass for the given name
261 // or return NULL if not.
262 ciKlass *check_get_unloaded_klass(ciKlass* accessing_klass, ciSymbol* name) {
263 return _factory->get_unloaded_klass(accessing_klass, name, false);
264 }
266 // Get a ciReturnAddress corresponding to the given bci.
267 // Ensures uniqueness of the result.
268 ciReturnAddress* get_return_address(int bci) {
269 return _factory->get_return_address(bci);
270 }
272 // Get a ciMethodData representing the methodData for a method
273 // with none.
274 ciMethodData* get_empty_methodData() {
275 return _factory->get_empty_methodData();
276 }
278 // General utility : get a buffer of some required length.
279 // Used in symbol creation.
280 char* name_buffer(int req_len);
282 // Is this thread currently in the VM state?
283 static bool is_in_vm();
285 // Helper routine for determining the validity of a compilation with
286 // respect to method dependencies (e.g. concurrent class loading).
287 void validate_compile_task_dependencies(ciMethod* target);
289 public:
290 enum {
291 MethodCompilable,
292 MethodCompilable_not_at_tier,
293 MethodCompilable_never
294 };
296 ciEnv(CompileTask* task, int system_dictionary_modification_counter);
297 // Used only during initialization of the ci
298 ciEnv(Arena* arena);
299 ~ciEnv();
301 OopRecorder* oop_recorder() { return _oop_recorder; }
302 void set_oop_recorder(OopRecorder* r) { _oop_recorder = r; }
304 DebugInformationRecorder* debug_info() { return _debug_info; }
305 void set_debug_info(DebugInformationRecorder* i) { _debug_info = i; }
307 Dependencies* dependencies() { return _dependencies; }
308 void set_dependencies(Dependencies* d) { _dependencies = d; }
310 // This is true if the compilation is not going to produce code.
311 // (It is reasonable to retry failed compilations.)
312 bool failing() { return _failure_reason != NULL; }
314 // Reason this compilation is failing, such as "too many basic blocks".
315 const char* failure_reason() { return _failure_reason; }
317 // Return state of appropriate compilability
318 int compilable() { return _compilable; }
320 const char* retry_message() const {
321 switch (_compilable) {
322 case ciEnv::MethodCompilable_not_at_tier:
323 return "retry at different tier";
324 case ciEnv::MethodCompilable_never:
325 return "not retryable";
326 case ciEnv::MethodCompilable:
327 return NULL;
328 default:
329 ShouldNotReachHere();
330 return NULL;
331 }
332 }
334 bool break_at_compile() { return _break_at_compile; }
335 void set_break_at_compile(bool z) { _break_at_compile = z; }
337 // Cache Jvmti state
338 void cache_jvmti_state();
339 bool jvmti_can_hotswap_or_post_breakpoint() const { return _jvmti_can_hotswap_or_post_breakpoint; }
340 bool jvmti_can_access_local_variables() const { return _jvmti_can_access_local_variables; }
341 bool jvmti_can_post_on_exceptions() const { return _jvmti_can_post_on_exceptions; }
343 // Cache DTrace flags
344 void cache_dtrace_flags();
345 bool dtrace_extended_probes() const { return _dtrace_extended_probes; }
346 bool dtrace_monitor_probes() const { return _dtrace_monitor_probes; }
347 bool dtrace_method_probes() const { return _dtrace_method_probes; }
348 bool dtrace_alloc_probes() const { return _dtrace_alloc_probes; }
350 // The compiler task which has created this env.
351 // May be useful to find out compile_id, comp_level, etc.
352 CompileTask* task() { return _task; }
353 // Handy forwards to the task:
354 int comp_level(); // task()->comp_level()
355 uint compile_id(); // task()->compile_id()
357 // Register the result of a compilation.
358 void register_method(ciMethod* target,
359 int entry_bci,
360 CodeOffsets* offsets,
361 int orig_pc_offset,
362 CodeBuffer* code_buffer,
363 int frame_words,
364 OopMapSet* oop_map_set,
365 ExceptionHandlerTable* handler_table,
366 ImplicitExceptionTable* inc_table,
367 AbstractCompiler* compiler,
368 int comp_level,
369 bool has_unsafe_access,
370 bool has_wide_vectors,
371 RTMState rtm_state = NoRTM);
374 // Access to certain well known ciObjects.
375 #define WK_KLASS_FUNC(name, ignore_s, ignore_o) \
376 ciInstanceKlass* name() { \
377 return _##name;\
378 }
379 WK_KLASSES_DO(WK_KLASS_FUNC)
380 #undef WK_KLASS_FUNC
382 ciInstance* NullPointerException_instance() {
383 assert(_NullPointerException_instance != NULL, "initialization problem");
384 return _NullPointerException_instance;
385 }
386 ciInstance* ArithmeticException_instance() {
387 assert(_ArithmeticException_instance != NULL, "initialization problem");
388 return _ArithmeticException_instance;
389 }
391 // Lazy constructors:
392 ciInstance* ArrayIndexOutOfBoundsException_instance();
393 ciInstance* ArrayStoreException_instance();
394 ciInstance* ClassCastException_instance();
396 ciInstance* the_null_string();
397 ciInstance* the_min_jint_string();
399 static ciSymbol* unloaded_cisymbol() {
400 return _unloaded_cisymbol;
401 }
402 static ciObjArrayKlass* unloaded_ciobjarrayklass() {
403 return _unloaded_ciobjarrayklass;
404 }
405 static ciInstanceKlass* unloaded_ciinstance_klass() {
406 return _unloaded_ciinstance_klass;
407 }
408 ciInstance* unloaded_ciinstance();
410 ciKlass* find_system_klass(ciSymbol* klass_name);
411 // Note: To find a class from its name string, use ciSymbol::make,
412 // but consider adding to vmSymbols.hpp instead.
414 // converts the ciKlass* representing the holder of a method into a
415 // ciInstanceKlass*. This is needed since the holder of a method in
416 // the bytecodes could be an array type. Basically this converts
417 // array types into java/lang/Object and other types stay as they are.
418 static ciInstanceKlass* get_instance_klass_for_declared_method_holder(ciKlass* klass);
420 // Return the machine-level offset of o, which must be an element of a.
421 // This may be used to form constant-loading expressions in lieu of simpler encodings.
422 int array_element_offset_in_bytes(ciArray* a, ciObject* o);
424 // Access to the compile-lifetime allocation arena.
425 Arena* arena() { return _arena; }
427 // What is the current compilation environment?
428 static ciEnv* current() { return CompilerThread::current()->env(); }
430 // Overload with current thread argument
431 static ciEnv* current(CompilerThread *thread) { return thread->env(); }
433 // Per-compiler data. (Used by C2 to publish the Compile* pointer.)
434 void* compiler_data() { return _compiler_data; }
435 void set_compiler_data(void* x) { _compiler_data = x; }
437 // Notice that a method has been inlined in the current compile;
438 // used only for statistics.
439 void notice_inlined_method(ciMethod* method);
441 // Total number of bytecodes in inlined methods in this compile
442 int num_inlined_bytecodes() const;
444 // Output stream for logging compilation info.
445 CompileLog* log() { return _log; }
446 void set_log(CompileLog* log) { _log = log; }
448 // Check for changes to the system dictionary during compilation
449 bool system_dictionary_modification_counter_changed();
451 void record_failure(const char* reason);
452 void record_method_not_compilable(const char* reason, bool all_tiers = true);
453 void record_out_of_memory_failure();
455 // RedefineClasses support
456 void metadata_do(void f(Metadata*)) { _factory->metadata_do(f); }
458 // Dump the compilation replay data for the ciEnv to the stream.
459 void dump_replay_data(int compile_id);
460 void dump_inline_data(int compile_id);
461 void dump_replay_data(outputStream* out);
462 void dump_replay_data_unsafe(outputStream* out);
463 void dump_compile_data(outputStream* out);
464 };
466 #endif // SHARE_VM_CI_CIENV_HPP