Thu, 27 Jan 2011 16:11:27 -0800
6990754: Use native memory and reference counting to implement SymbolTable
Summary: move symbols from permgen into C heap and reference count them
Reviewed-by: never, acorn, jmasa, stefank
1 /*
2 * Copyright (c) 1998, 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.
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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.
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23 */
25 #include "precompiled.hpp"
26 #include "classfile/systemDictionary.hpp"
27 #include "classfile/vmSymbols.hpp"
28 #include "compiler/compileBroker.hpp"
29 #include "oops/oop.inline.hpp"
30 #include "runtime/init.hpp"
31 #include "runtime/java.hpp"
32 #include "runtime/javaCalls.hpp"
33 #include "runtime/threadCritical.hpp"
34 #include "utilities/events.hpp"
35 #include "utilities/exceptions.hpp"
36 #ifdef TARGET_OS_FAMILY_linux
37 # include "thread_linux.inline.hpp"
38 #endif
39 #ifdef TARGET_OS_FAMILY_solaris
40 # include "thread_solaris.inline.hpp"
41 #endif
42 #ifdef TARGET_OS_FAMILY_windows
43 # include "thread_windows.inline.hpp"
44 #endif
47 // Implementation of ThreadShadow
48 void check_ThreadShadow() {
49 const ByteSize offset1 = byte_offset_of(ThreadShadow, _pending_exception);
50 const ByteSize offset2 = Thread::pending_exception_offset();
51 if (offset1 != offset2) fatal("ThreadShadow::_pending_exception is not positioned correctly");
52 }
55 void ThreadShadow::set_pending_exception(oop exception, const char* file, int line) {
56 assert(exception != NULL && exception->is_oop(), "invalid exception oop");
57 _pending_exception = exception;
58 _exception_file = file;
59 _exception_line = line;
60 }
62 void ThreadShadow::clear_pending_exception() {
63 if (TraceClearedExceptions) {
64 if (_pending_exception != NULL) {
65 tty->print_cr("Thread::clear_pending_exception: cleared exception:");
66 _pending_exception->print();
67 }
68 }
69 _pending_exception = NULL;
70 _exception_file = NULL;
71 _exception_line = 0;
72 }
73 // Implementation of Exceptions
75 bool Exceptions::special_exception(Thread* thread, const char* file, int line, Handle h_exception) {
76 // bootstrapping check
77 if (!Universe::is_fully_initialized()) {
78 vm_exit_during_initialization(h_exception);
79 ShouldNotReachHere();
80 }
82 #ifdef ASSERT
83 // Check for trying to throw stack overflow before initialization is complete
84 // to prevent infinite recursion trying to initialize stack overflow without
85 // adequate stack space.
86 // This can happen with stress testing a large value of StackShadowPages
87 if (h_exception()->klass() == SystemDictionary::StackOverflowError_klass()) {
88 instanceKlass* ik = instanceKlass::cast(h_exception->klass());
89 assert(ik->is_initialized(),
90 "need to increase min_stack_allowed calculation");
91 }
92 #endif // ASSERT
94 if (thread->is_VM_thread()
95 || thread->is_Compiler_thread() ) {
96 // We do not care what kind of exception we get for the vm-thread or a thread which
97 // is compiling. We just install a dummy exception object
98 thread->set_pending_exception(Universe::vm_exception(), file, line);
99 return true;
100 }
102 return false;
103 }
105 bool Exceptions::special_exception(Thread* thread, const char* file, int line, Symbol* h_name, const char* message) {
106 // bootstrapping check
107 if (!Universe::is_fully_initialized()) {
108 if (h_name == NULL) {
109 // atleast an informative message.
110 vm_exit_during_initialization("Exception", message);
111 } else {
112 vm_exit_during_initialization(h_name, message);
113 }
114 ShouldNotReachHere();
115 }
117 if (thread->is_VM_thread()
118 || thread->is_Compiler_thread() ) {
119 // We do not care what kind of exception we get for the vm-thread or a thread which
120 // is compiling. We just install a dummy exception object
121 thread->set_pending_exception(Universe::vm_exception(), file, line);
122 return true;
123 }
124 return false;
125 }
127 // This method should only be called from generated code,
128 // therefore the exception oop should be in the oopmap.
129 void Exceptions::_throw_oop(Thread* thread, const char* file, int line, oop exception) {
130 assert(exception != NULL, "exception should not be NULL");
131 Handle h_exception = Handle(thread, exception);
132 _throw(thread, file, line, h_exception);
133 }
135 void Exceptions::_throw(Thread* thread, const char* file, int line, Handle h_exception, const char* message) {
136 assert(h_exception() != NULL, "exception should not be NULL");
138 // tracing (do this up front - so it works during boot strapping)
139 if (TraceExceptions) {
140 ttyLocker ttyl;
141 ResourceMark rm;
142 tty->print_cr("Exception <%s>%s%s (" INTPTR_FORMAT " ) \n"
143 "thrown [%s, line %d]\nfor thread " INTPTR_FORMAT,
144 h_exception->print_value_string(),
145 message ? ": " : "", message ? message : "",
146 (address)h_exception(), file, line, thread);
147 }
148 // for AbortVMOnException flag
149 NOT_PRODUCT(Exceptions::debug_check_abort(h_exception, message));
151 // Check for special boot-strapping/vm-thread handling
152 if (special_exception(thread, file, line, h_exception)) return;
154 assert(h_exception->is_a(SystemDictionary::Throwable_klass()), "exception is not a subclass of java/lang/Throwable");
156 // set the pending exception
157 thread->set_pending_exception(h_exception(), file, line);
159 // vm log
160 Events::log("throw_exception " INTPTR_FORMAT, (address)h_exception());
161 }
164 void Exceptions::_throw_msg(Thread* thread, const char* file, int line, Symbol* h_name, const char* message, Handle h_loader, Handle h_protection_domain) {
165 // Check for special boot-strapping/vm-thread handling
166 if (special_exception(thread, file, line, h_name, message)) return;
167 // Create and throw exception
168 Handle h_cause(thread, NULL);
169 Handle h_exception = new_exception(thread, h_name, message, h_cause, h_loader, h_protection_domain);
170 _throw(thread, file, line, h_exception, message);
171 }
173 // Throw an exception with a message and a cause
174 void Exceptions::_throw_msg_cause(Thread* thread, const char* file, int line, Symbol* h_name, const char* message, Handle h_cause, Handle h_loader, Handle h_protection_domain) {
175 // Check for special boot-strapping/vm-thread handling
176 if (special_exception(thread, file, line, h_name, message)) return;
177 // Create and throw exception and init cause
178 Handle h_exception = new_exception(thread, h_name, message, h_cause, h_loader, h_protection_domain);
179 _throw(thread, file, line, h_exception, message);
180 }
182 // This version already has a handle for name
183 void Exceptions::_throw_msg(Thread* thread, const char* file, int line,
184 Symbol* name, const char* message) {
185 Handle h_loader(thread, NULL);
186 Handle h_protection_domain(thread, NULL);
187 Exceptions::_throw_msg(thread, file, line, name, message, h_loader, h_protection_domain);
188 }
190 // This version already has a handle for name
191 void Exceptions::_throw_msg_cause(Thread* thread, const char* file, int line,
192 Symbol* name, const char* message, Handle cause) {
193 Handle h_loader(thread, NULL);
194 Handle h_protection_domain(thread, NULL);
195 Exceptions::_throw_msg_cause(thread, file, line, name, message, cause, h_loader, h_protection_domain);
196 }
198 void Exceptions::_throw_args(Thread* thread, const char* file, int line, Symbol* h_name, Symbol* h_signature, JavaCallArguments *args) {
199 // Check for special boot-strapping/vm-thread handling
200 if (special_exception(thread, file, line, h_name, NULL)) return;
201 // Create and throw exception
202 Handle h_loader(thread, NULL);
203 Handle h_prot(thread, NULL);
204 Handle h_cause(thread, NULL);
205 Handle exception = new_exception(thread, h_name, h_signature, args, h_cause, h_loader, h_prot);
206 _throw(thread, file, line, exception);
207 }
210 void Exceptions::throw_stack_overflow_exception(Thread* THREAD, const char* file, int line) {
211 Handle exception;
212 if (!THREAD->has_pending_exception()) {
213 klassOop k = SystemDictionary::StackOverflowError_klass();
214 oop e = instanceKlass::cast(k)->allocate_instance(CHECK);
215 exception = Handle(THREAD, e); // fill_in_stack trace does gc
216 assert(instanceKlass::cast(k)->is_initialized(), "need to increase min_stack_allowed calculation");
217 if (StackTraceInThrowable) {
218 java_lang_Throwable::fill_in_stack_trace(exception);
219 }
220 } else {
221 // if prior exception, throw that one instead
222 exception = Handle(THREAD, THREAD->pending_exception());
223 }
224 _throw_oop(THREAD, file, line, exception());
225 }
227 void Exceptions::fthrow(Thread* thread, const char* file, int line, Symbol* h_name, const char* format, ...) {
228 const int max_msg_size = 1024;
229 va_list ap;
230 va_start(ap, format);
231 char msg[max_msg_size];
232 vsnprintf(msg, max_msg_size, format, ap);
233 msg[max_msg_size-1] = '\0';
234 va_end(ap);
235 _throw_msg(thread, file, line, h_name, msg);
236 }
238 // Creates an exception oop, calls the <init> method with the given signature.
239 // and returns a Handle
240 // Initializes the cause if cause non-null
241 Handle Exceptions::new_exception(Thread *thread, Symbol* h_name,
242 Symbol* signature,
243 JavaCallArguments *args,
244 Handle h_cause, Handle h_loader,
245 Handle h_protection_domain) {
246 assert(Universe::is_fully_initialized(),
247 "cannot be called during initialization");
248 assert(thread->is_Java_thread(), "can only be called by a Java thread");
249 assert(!thread->has_pending_exception(), "already has exception");
251 Handle h_exception;
253 // Resolve exception klass
254 klassOop ik = SystemDictionary::resolve_or_fail(h_name, h_loader, h_protection_domain, true, thread);
255 instanceKlassHandle klass (thread, ik);
257 if (!thread->has_pending_exception()) {
258 assert(klass.not_null(), "klass must exist");
259 // We are about to create an instance - so make sure that klass is initialized
260 klass->initialize(thread);
261 if (!thread->has_pending_exception()) {
262 // Allocate new exception
263 h_exception = klass->allocate_instance_handle(thread);
264 if (!thread->has_pending_exception()) {
265 JavaValue result(T_VOID);
266 args->set_receiver(h_exception);
267 // Call constructor
268 JavaCalls::call_special(&result, klass,
269 vmSymbols::object_initializer_name(),
270 signature,
271 args,
272 thread);
274 }
275 }
277 // Future: object initializer should take a cause argument
278 if (h_cause() != NULL) {
279 assert(h_cause->is_a(SystemDictionary::Throwable_klass()),
280 "exception cause is not a subclass of java/lang/Throwable");
281 JavaValue result1(T_OBJECT);
282 JavaCallArguments args1;
283 args1.set_receiver(h_exception);
284 args1.push_oop(h_cause);
285 JavaCalls::call_virtual(&result1, klass,
286 vmSymbols::initCause_name(),
287 vmSymbols::throwable_throwable_signature(),
288 &args1,
289 thread);
290 }
291 }
293 // Check if another exception was thrown in the process, if so rethrow that one
294 if (thread->has_pending_exception()) {
295 h_exception = Handle(thread, thread->pending_exception());
296 thread->clear_pending_exception();
297 }
298 return h_exception;
299 }
301 // Convenience method. Calls either the <init>() or <init>(String) method when
302 // creating a new exception
303 Handle Exceptions::new_exception(Thread* thread, Symbol* h_name,
304 const char* message, Handle h_cause,
305 Handle h_loader,
306 Handle h_protection_domain,
307 ExceptionMsgToUtf8Mode to_utf8_safe) {
308 JavaCallArguments args;
309 Symbol* signature = NULL;
310 if (message == NULL) {
311 signature = vmSymbols::void_method_signature();
312 } else {
313 // We want to allocate storage, but we can't do that if there's
314 // a pending exception, so we preserve any pending exception
315 // around the allocation.
316 // If we get an exception from the allocation, prefer that to
317 // the exception we are trying to build, or the pending exception.
318 // This is sort of like what PRESERVE_EXCEPTION_MARK does, except
319 // for the preferencing and the early returns.
320 Handle incoming_exception (thread, NULL);
321 if (thread->has_pending_exception()) {
322 incoming_exception = Handle(thread, thread->pending_exception());
323 thread->clear_pending_exception();
324 }
325 Handle msg;
326 if (to_utf8_safe == safe_to_utf8) {
327 // Make a java UTF8 string.
328 msg = java_lang_String::create_from_str(message, thread);
329 } else {
330 // Make a java string keeping the encoding scheme of the original string.
331 msg = java_lang_String::create_from_platform_dependent_str(message, thread);
332 }
333 if (thread->has_pending_exception()) {
334 Handle exception(thread, thread->pending_exception());
335 thread->clear_pending_exception();
336 return exception;
337 }
338 if (incoming_exception.not_null()) {
339 return incoming_exception;
340 }
341 args.push_oop(msg);
342 signature = vmSymbols::string_void_signature();
343 }
344 return new_exception(thread, h_name, signature, &args, h_cause, h_loader, h_protection_domain);
345 }
347 // Another convenience method that creates handles for null class loaders and
348 // protection domains and null causes.
349 // If the last parameter 'to_utf8_mode' is safe_to_utf8,
350 // it means we can safely ignore the encoding scheme of the message string and
351 // convert it directly to a java UTF8 string. Otherwise, we need to take the
352 // encoding scheme of the string into account. One thing we should do at some
353 // point is to push this flag down to class java_lang_String since other
354 // classes may need similar functionalities.
355 Handle Exceptions::new_exception(Thread* thread,
356 Symbol* name,
357 const char* message,
358 ExceptionMsgToUtf8Mode to_utf8_safe) {
360 Handle h_loader(thread, NULL);
361 Handle h_prot(thread, NULL);
362 Handle h_cause(thread, NULL);
363 return Exceptions::new_exception(thread, name, message, h_cause, h_loader,
364 h_prot, to_utf8_safe);
365 }
367 // Implementation of ExceptionMark
369 ExceptionMark::ExceptionMark(Thread*& thread) {
370 thread = Thread::current();
371 _thread = thread;
372 if (_thread->has_pending_exception()) {
373 oop exception = _thread->pending_exception();
374 _thread->clear_pending_exception(); // Needed to avoid infinite recursion
375 exception->print();
376 fatal("ExceptionMark constructor expects no pending exceptions");
377 }
378 }
381 ExceptionMark::~ExceptionMark() {
382 if (_thread->has_pending_exception()) {
383 Handle exception(_thread, _thread->pending_exception());
384 _thread->clear_pending_exception(); // Needed to avoid infinite recursion
385 if (is_init_completed()) {
386 exception->print();
387 fatal("ExceptionMark destructor expects no pending exceptions");
388 } else {
389 vm_exit_during_initialization(exception);
390 }
391 }
392 }
394 // ----------------------------------------------------------------------------------------
396 #ifndef PRODUCT
397 // caller frees value_string if necessary
398 void Exceptions::debug_check_abort(const char *value_string, const char* message) {
399 if (AbortVMOnException != NULL && value_string != NULL &&
400 strstr(value_string, AbortVMOnException)) {
401 if (AbortVMOnExceptionMessage == NULL || message == NULL ||
402 strcmp(message, AbortVMOnExceptionMessage) == 0) {
403 fatal(err_msg("Saw %s, aborting", value_string));
404 }
405 }
406 }
408 void Exceptions::debug_check_abort(Handle exception, const char* message) {
409 if (AbortVMOnException != NULL) {
410 ResourceMark rm;
411 if (message == NULL && exception->is_a(SystemDictionary::Throwable_klass())) {
412 oop msg = java_lang_Throwable::message(exception);
413 if (msg != NULL) {
414 message = java_lang_String::as_utf8_string(msg);
415 }
416 }
417 debug_check_abort(instanceKlass::cast(exception()->klass())->external_name(), message);
418 }
419 }
420 #endif