1 /*
  2  * Copyright (c) 1998, 2026, 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 #include "classfile/javaClasses.hpp"
 26 #include "classfile/systemDictionary.hpp"
 27 #include "classfile/vmClasses.hpp"
 28 #include "classfile/vmSymbols.hpp"
 29 #include "compiler/compileBroker.hpp"
 30 #include "logging/log.hpp"
 31 #include "logging/logStream.hpp"
 32 #include "memory/resourceArea.hpp"
 33 #include "memory/universe.hpp"
 34 #include "oops/oop.inline.hpp"
 35 #include "runtime/handles.inline.hpp"
 36 #include "runtime/init.hpp"
 37 #include "runtime/java.hpp"
 38 #include "runtime/javaCalls.hpp"
 39 #include "runtime/javaThread.hpp"
 40 #include "runtime/os.hpp"
 41 #include "utilities/events.hpp"
 42 #include "utilities/exceptions.hpp"
 43 #include "utilities/utf8.hpp"
 44 
 45 // Limit exception message components to 64K (the same max as Symbols)
 46 #define MAX_LEN 65535
 47 
 48 // Implementation of ThreadShadow
 49 void check_ThreadShadow() {
 50   const ByteSize offset1 = byte_offset_of(ThreadShadow, _pending_exception);
 51   const ByteSize offset2 = Thread::pending_exception_offset();
 52   if (offset1 != offset2) fatal("ThreadShadow::_pending_exception is not positioned correctly");
 53 }
 54 
 55 
 56 void ThreadShadow::set_pending_exception(oop exception, const char* file, int line) {
 57   assert(exception != nullptr && oopDesc::is_oop(exception), "invalid exception oop");
 58   _pending_exception = exception;
 59   _exception_file    = file;
 60   _exception_line    = line;
 61 }
 62 
 63 void ThreadShadow::clear_pending_exception() {
 64   assert(_pending_exception == nullptr || !_pending_exception->is_a(vmClasses::PreemptedException_klass()),
 65          "unexpected PreemptedException, missing NoPreemptMark?");
 66   LogTarget(Debug, exceptions) lt;
 67   if (_pending_exception != nullptr && lt.is_enabled()) {
 68     ResourceMark rm;
 69     LogStream ls(lt);
 70     ls.print("Thread::clear_pending_exception: cleared exception:");
 71     _pending_exception->print_on(&ls);
 72   }
 73   _pending_exception = nullptr;
 74   _exception_file    = nullptr;
 75   _exception_line    = 0;
 76 }
 77 
 78 void ThreadShadow::clear_pending_nonasync_exception() {
 79   // Do not clear probable async exceptions.
 80   if ((_pending_exception->klass() != vmClasses::InternalError_klass() ||
 81        java_lang_InternalError::during_unsafe_access(_pending_exception) != JNI_TRUE)) {
 82     clear_pending_exception();
 83   }
 84 }
 85 
 86 void ThreadShadow::set_pending_preempted_exception() {
 87   assert(!has_pending_exception(), "");
 88   // We always install the same pre-allocated exception since we only
 89   // want to use the TRAPS mechanism to bail out from all methods until
 90   // reaching the one using the CHECK_AND_CLEAR_PREEMPTED macro.
 91   set_pending_exception(Universe::preempted_exception_instance(), __FILE__, __LINE__);
 92 }
 93 
 94 void ThreadShadow::clear_pending_preempted_exception() {
 95   assert(has_pending_exception(), "");
 96   if (pending_exception()->is_a(vmClasses::PreemptedException_klass())) {
 97     _pending_exception = nullptr;
 98     _exception_file    = nullptr;
 99     _exception_line    = 0;
100   }
101 }
102 
103 #ifdef ASSERT
104 void ThreadShadow::check_preempted_exception() {
105   assert(has_pending_exception(), "");
106   assert(pending_exception()->is_a(vmClasses::PreemptedException_klass()), "should only be PreemptedException");
107 }
108 #endif
109 
110 // Implementation of Exceptions
111 
112 bool Exceptions::special_exception(JavaThread* thread, const char* file, int line, Handle h_exception, Symbol* h_name, const char* message) {
113   assert(h_exception.is_null() != (h_name == nullptr), "either exception (" PTR_FORMAT ") or "
114          "symbol (" PTR_FORMAT ") must be non-null but not both", p2i(h_exception()), p2i(h_name));
115 
116   // bootstrapping check
117   if (!Universe::is_fully_initialized()) {
118     if (h_exception.not_null()) {
119       vm_exit_during_initialization(h_exception);
120     } else if (h_name == nullptr) {
121       // at least an informative message.
122       vm_exit_during_initialization("Exception", message);
123     } else {
124       vm_exit_during_initialization(h_name, message);
125     }
126    ShouldNotReachHere();
127   }
128 
129 #ifdef ASSERT
130   // Check for trying to throw stack overflow before initialization is complete
131   // to prevent infinite recursion trying to initialize stack overflow without
132   // adequate stack space.
133   // This can happen with stress testing a large value of StackShadowPages
134   if (h_exception.not_null() && h_exception()->klass() == vmClasses::StackOverflowError_klass()) {
135     InstanceKlass* ik = InstanceKlass::cast(h_exception->klass());
136     assert(ik->is_initialized(),
137            "need to increase java_thread_min_stack_allowed calculation");
138   }
139 #endif // ASSERT
140 
141   if (h_exception.is_null() && !thread->can_call_java()) {
142     if (log_is_enabled(Info, exceptions)) {
143       ResourceMark rm(thread);
144       const char* exc_value = h_name != nullptr ? h_name->as_C_string() : "null";
145       log_info(exceptions)("Thread cannot call Java so instead of throwing exception <%.*s%s%.*s> (" PTR_FORMAT ") \n"
146                            "at [%s, line %d]\nfor thread " PTR_FORMAT ",\n"
147                            "throwing pre-allocated exception: %s",
148                            MAX_LEN, exc_value, message ? ": " : "",
149                            MAX_LEN, message ? message : "",
150                            p2i(h_exception()), file, line, p2i(thread),
151                            Universe::vm_exception()->print_value_string());
152     }
153     // We do not care what kind of exception we get for a thread which
154     // is compiling.  We just install a dummy exception object
155     thread->set_pending_exception(Universe::vm_exception(), file, line);
156     return true;
157   }
158 
159   return false;
160 }
161 
162 // This method should only be called from generated code,
163 // therefore the exception oop should be in the oopmap.
164 void Exceptions::_throw_oop(JavaThread* thread, const char* file, int line, oop exception) {
165   assert(exception != nullptr, "exception should not be null");
166   Handle h_exception(thread, exception);
167   _throw(thread, file, line, h_exception);
168 }
169 
170 void Exceptions::_throw(JavaThread* thread, const char* file, int line, Handle h_exception, const char* message) {
171   ResourceMark rm(thread);
172   assert(h_exception() != nullptr, "exception should not be null");
173 
174   // tracing (do this up front - so it works during boot strapping)
175   // Note, the print_value_string() argument is not called unless logging is enabled!
176   log_info(exceptions)("Exception <%.*s%s%.*s> (" PTR_FORMAT ") \n"
177                        "thrown [%s, line %d]\nfor thread " PTR_FORMAT,
178                        MAX_LEN, h_exception->print_value_string(),
179                        message ? ": " : "",
180                        MAX_LEN, message ? message : "",
181                        p2i(h_exception()), file, line, p2i(thread));
182   if (log_is_enabled(Info, exceptions, stacktrace)) {
183     log_exception_stacktrace(h_exception);
184   }
185 
186   // for AbortVMOnException flag
187   Exceptions::debug_check_abort(h_exception, message);
188 
189   // Check for special boot-strapping/compiler-thread handling
190   if (special_exception(thread, file, line, h_exception)) {
191     return;
192   }
193 
194   if (h_exception->is_a(vmClasses::VirtualMachineError_klass())) {
195     // Remove the ScopedValue bindings in case we got a virtual machine
196     // Error while we were trying to manipulate ScopedValue bindings.
197     thread->clear_scopedValueBindings();
198 
199     if (h_exception->is_a(vmClasses::OutOfMemoryError_klass())) {
200       count_out_of_memory_exceptions(h_exception);
201     }
202   }
203 
204   if (h_exception->is_a(vmClasses::LinkageError_klass())) {
205     _linkage_errors.add_then_fetch(1, memory_order_relaxed);
206   }
207 
208   assert(h_exception->is_a(vmClasses::Throwable_klass()), "exception is not a subclass of java/lang/Throwable");
209 
210   // set the pending exception
211   thread->set_pending_exception(h_exception(), file, line);
212 
213   // vm log
214   Events::log_exception(thread, h_exception, message, file, line, MAX_LEN);
215 }
216 
217 
218 void Exceptions::_throw_msg(JavaThread* thread, const char* file, int line, Symbol* name, const char* message,
219                             Handle h_loader) {
220   // Check for special boot-strapping/compiler-thread handling
221   if (special_exception(thread, file, line, Handle(), name, message)) return;
222   // Create and throw exception
223   Handle h_cause(thread, nullptr);
224   Handle h_exception = new_exception(thread, name, message, h_cause, h_loader);
225   _throw(thread, file, line, h_exception, message);
226 }
227 
228 void Exceptions::_throw_msg_cause(JavaThread* thread, const char* file, int line, Symbol* name, const char* message, Handle h_cause,
229                                   Handle h_loader) {
230   // Check for special boot-strapping/compiler-thread handling
231   if (special_exception(thread, file, line, Handle(), name, message)) return;
232   // Create and throw exception and init cause
233   Handle h_exception = new_exception(thread, name, message, h_cause, h_loader);
234   _throw(thread, file, line, h_exception, message);
235 }
236 
237 void Exceptions::_throw_cause(JavaThread* thread, const char* file, int line, Symbol* name, Handle h_cause,
238                               Handle h_loader) {
239   // Check for special boot-strapping/compiler-thread handling
240   if (special_exception(thread, file, line, Handle(), name)) return;
241   // Create and throw exception
242   Handle h_exception = new_exception(thread, name, h_cause, h_loader);
243   _throw(thread, file, line, h_exception, nullptr);
244 }
245 
246 void Exceptions::_throw_args(JavaThread* thread, const char* file, int line, Symbol* name, Symbol* signature, JavaCallArguments *args) {
247   // Check for special boot-strapping/compiler-thread handling
248   if (special_exception(thread, file, line, Handle(), name, nullptr)) return;
249   // Create and throw exception
250   Handle h_loader(thread, nullptr);
251   Handle h_prot(thread, nullptr);
252   Handle exception = new_exception(thread, name, signature, args, h_loader, h_prot);
253   _throw(thread, file, line, exception);
254 }
255 
256 
257 // Methods for default parameters.
258 // NOTE: These must be here (and not in the header file) because of include circularities.
259 void Exceptions::_throw_msg_cause(JavaThread* thread, const char* file, int line, Symbol* name, const char* message, Handle h_cause) {
260   _throw_msg_cause(thread, file, line, name, message, h_cause, Handle());
261 }
262 void Exceptions::_throw_msg(JavaThread* thread, const char* file, int line, Symbol* name, const char* message) {
263   _throw_msg(thread, file, line, name, message, Handle());
264 }
265 void Exceptions::_throw_cause(JavaThread* thread, const char* file, int line, Symbol* name, Handle h_cause) {
266   _throw_cause(thread, file, line, name, h_cause, Handle());
267 }
268 
269 
270 void Exceptions::increment_stack_overflow_errors() {
271   Exceptions::_stack_overflow_errors.add_then_fetch(1, memory_order_relaxed);
272 }
273 
274 void Exceptions::throw_stack_overflow_exception(JavaThread* THREAD, const char* file, int line, const methodHandle& method) {
275   Handle exception;
276   if (!THREAD->has_pending_exception()) {
277     InstanceKlass* k = vmClasses::StackOverflowError_klass();
278     oop e = k->allocate_instance(CHECK);
279     exception = Handle(THREAD, e);  // fill_in_stack trace does gc
280     assert(k->is_initialized(), "need to increase java_thread_min_stack_allowed calculation");
281     if (StackTraceInThrowable) {
282       java_lang_Throwable::fill_in_stack_trace(exception, method);
283     }
284     // Increment counter for hs_err file reporting
285     increment_stack_overflow_errors();
286   } else {
287     // if prior exception, throw that one instead
288     exception = Handle(THREAD, THREAD->pending_exception());
289   }
290   _throw(THREAD, file, line, exception);
291 }
292 
293 // All callers are expected to have ensured that the incoming expanded format string
294 // will be within reasonable limits - specifically we will never hit the INT_MAX limit
295 // of os::vsnprintf when it tries to report how big a buffer is needed. Even so we
296 // further limit the formatted output to 1024 characters.
297 void Exceptions::fthrow(JavaThread* thread, const char* file, int line, Symbol* h_name, const char* format, ...) {
298   const int max_msg_size = 1024;
299   va_list ap;
300   va_start(ap, format);
301   char msg[max_msg_size];
302   int ret = os::vsnprintf(msg, max_msg_size, format, ap);
303   va_end(ap);
304 
305   // If ret == -1 then either there was a format conversion error, or the required buffer size
306   // exceeds INT_MAX and so couldn't be returned (undocumented behaviour of vsnprintf). Depending
307   // on the platform the buffer may be filled to its capacity (Linux), filled to the conversion
308   // that encountered the overflow (macOS), or is empty (Windows), so it is possible we
309   // have a truncated UTF-8 sequence. Similarly, if the buffer was too small and ret >= max_msg_size
310   // we may also have a truncated UTF-8 sequence. In such cases we need to fix the buffer so the UTF-8
311   // sequence is valid.
312   assert(ret != -1, "Caller should have ensured the incoming format string is size limited!");
313   if (ret == -1 || ret >= max_msg_size) {
314     int len = (int) strlen(msg);
315     if (len > 0) {
316       // Truncation will only happen if the buffer was filled by vsnprintf,
317       // otherwise vsnprintf already terminated filling it at a well-defined point.
318       // But as this is not a clearly specified area we will perform our own UTF8
319       // truncation anyway - though for those well-defined termination points it
320       // will be a no-op.
321       UTF8::truncate_to_legal_utf8((unsigned char*)msg, len + 1);
322     }
323   }
324   // UTF8::is_legal_utf8 should actually be called is_legal_utf8_class_name as the final
325   // parameter controls a check for a specific character appearing in the "name", which is only
326   // allowed for classfile versions <= 47. We pass `true` so that we allow such strings as this code
327   // know nothing about the actual string content.
328   assert(UTF8::is_legal_utf8((const unsigned char*)msg, strlen(msg), true), "must be");
329   _throw_msg(thread, file, line, h_name, msg);
330 }
331 
332 
333 // Creates an exception oop, calls the <init> method with the given signature.
334 // and returns a Handle
335 Handle Exceptions::new_exception(JavaThread* thread, Symbol* name,
336                                  Symbol* signature, JavaCallArguments *args,
337                                  Handle h_loader) {
338   assert(Universe::is_fully_initialized(),
339     "cannot be called during initialization");
340   assert(!thread->has_pending_exception(), "already has exception");
341 
342   Handle h_exception;
343 
344   // Resolve exception klass, and check for pending exception below.
345   Klass* klass = SystemDictionary::resolve_or_fail(name, h_loader, true, thread);
346 
347   if (!thread->has_pending_exception()) {
348     assert(klass != nullptr, "klass must exist");
349     // We could get here while linking or initializing a klass
350     // from a preemptable call. Don't preempt here since before
351     // the PreemptedException is propagated we might make an upcall
352     // to Java to initialize the object with the cause of exception.
353     NoPreemptMark npm(thread);
354     h_exception = JavaCalls::construct_new_instance(InstanceKlass::cast(klass),
355                                 signature,
356                                 args,
357                                 thread);
358   }
359 
360   // Check if another exception was thrown in the process, if so rethrow that one
361   if (thread->has_pending_exception()) {
362     h_exception = Handle(thread, thread->pending_exception());
363     thread->clear_pending_exception();
364   }
365   return h_exception;
366 }
367 
368 // Creates an exception oop, calls the <init> method with the given signature.
369 // and returns a Handle
370 // Initializes the cause if cause non-null
371 Handle Exceptions::new_exception(JavaThread* thread, Symbol* name,
372                                  Symbol* signature, JavaCallArguments *args,
373                                  Handle h_cause,
374                                  Handle h_loader) {
375   Handle h_exception = new_exception(thread, name, signature, args, h_loader);
376 
377   // Future: object initializer should take a cause argument
378   if (h_cause.not_null()) {
379     assert(h_cause->is_a(vmClasses::Throwable_klass()),
380         "exception cause is not a subclass of java/lang/Throwable");
381     JavaValue result1(T_OBJECT);
382     JavaCallArguments args1;
383     args1.set_receiver(h_exception);
384     args1.push_oop(h_cause);
385     JavaCalls::call_virtual(&result1, h_exception->klass(),
386                                       vmSymbols::initCause_name(),
387                                       vmSymbols::throwable_throwable_signature(),
388                                       &args1,
389                                       thread);
390   }
391 
392   // Check if another exception was thrown in the process, if so rethrow that one
393   if (thread->has_pending_exception()) {
394     h_exception = Handle(thread, thread->pending_exception());
395     thread->clear_pending_exception();
396   }
397   return h_exception;
398 }
399 
400 // Convenience method. Calls either the <init>() or <init>(Throwable) method when
401 // creating a new exception
402 Handle Exceptions::new_exception(JavaThread* thread, Symbol* name,
403                                  Handle h_cause,
404                                  Handle h_loader,
405                                  ExceptionMsgToUtf8Mode to_utf8_safe) {
406   JavaCallArguments args;
407   Symbol* signature = nullptr;
408   if (h_cause.is_null()) {
409     signature = vmSymbols::void_method_signature();
410   } else {
411     signature = vmSymbols::throwable_void_signature();
412     args.push_oop(h_cause);
413   }
414   return new_exception(thread, name, signature, &args, h_loader);
415 }
416 
417 // Convenience method. Calls either the <init>() or <init>(String) method when
418 // creating a new exception
419 Handle Exceptions::new_exception(JavaThread* thread, Symbol* name,
420                                  const char* message, Handle h_cause,
421                                  Handle h_loader,
422                                  ExceptionMsgToUtf8Mode to_utf8_safe) {
423   JavaCallArguments args;
424   Symbol* signature = nullptr;
425   if (message == nullptr) {
426     signature = vmSymbols::void_method_signature();
427   } else {
428     // There should be no pending exception. The caller is responsible for not calling
429     // this with a pending exception.
430     Handle incoming_exception;
431     if (thread->has_pending_exception()) {
432       incoming_exception = Handle(thread, thread->pending_exception());
433       thread->clear_pending_exception();
434       ResourceMark rm(thread);
435       assert(incoming_exception.is_null(), "Pending exception while throwing %s %s", name->as_C_string(), message);
436     }
437     Handle msg;
438     if (to_utf8_safe == safe_to_utf8) {
439       // Make a java UTF8 string.
440       msg = java_lang_String::create_from_str(message, thread);
441     } else {
442       // Make a java string keeping the encoding scheme of the original string.
443       msg = java_lang_String::create_from_platform_dependent_str(message, thread);
444     }
445     // If we get an exception from the allocation, prefer that to
446     // the exception we are trying to build, or the pending exception (in product mode)
447     if (thread->has_pending_exception()) {
448       Handle exception(thread, thread->pending_exception());
449       thread->clear_pending_exception();
450       return exception;
451     }
452     if (incoming_exception.not_null()) {
453       return incoming_exception;
454     }
455     args.push_oop(msg);
456     signature = vmSymbols::string_void_signature();
457   }
458   return new_exception(thread, name, signature, &args, h_cause, h_loader);
459 }
460 
461 // Another convenience method that creates handles for null class loaders and null causes.
462 // If the last parameter 'to_utf8_mode' is safe_to_utf8,
463 // it means we can safely ignore the encoding scheme of the message string and
464 // convert it directly to a java UTF8 string. Otherwise, we need to take the
465 // encoding scheme of the string into account. One thing we should do at some
466 // point is to push this flag down to class java_lang_String since other
467 // classes may need similar functionalities.
468 Handle Exceptions::new_exception(JavaThread* thread, Symbol* name,
469                                  const char* message,
470                                  ExceptionMsgToUtf8Mode to_utf8_safe) {
471 
472   Handle h_loader;
473   Handle h_cause;
474   return Exceptions::new_exception(thread, name, message, h_cause, h_loader,
475                                    to_utf8_safe);
476 }
477 
478 // invokedynamic uses wrap_dynamic_exception for:
479 //    - bootstrap method resolution
480 //    - post call to MethodHandleNatives::linkCallSite
481 // dynamically computed constant uses wrap_dynamic_exception for:
482 //    - bootstrap method resolution
483 //    - post call to MethodHandleNatives::linkDynamicConstant
484 void Exceptions::wrap_dynamic_exception(bool is_indy, JavaThread* THREAD) {
485   if (THREAD->has_pending_exception()) {
486     bool log_indy = log_is_enabled(Debug, methodhandles, indy) && is_indy;
487     bool log_condy = log_is_enabled(Debug, methodhandles, condy) && !is_indy;
488     LogStreamHandle(Debug, methodhandles, indy) lsh_indy;
489     LogStreamHandle(Debug, methodhandles, condy) lsh_condy;
490     LogStream* ls = nullptr;
491     if (log_indy) {
492       ls = &lsh_indy;
493     } else if (log_condy) {
494       ls = &lsh_condy;
495     }
496     oop exception = THREAD->pending_exception();
497 
498     // See the "Linking Exceptions" section for the invokedynamic instruction
499     // in JVMS 6.5.
500     if (exception->is_a(vmClasses::Error_klass())) {
501       // Pass through an Error, including BootstrapMethodError, any other form
502       // of linkage error, or say OutOfMemoryError
503       if (ls != nullptr) {
504         ResourceMark rm(THREAD);
505         ls->print_cr("bootstrap method invocation wraps BSME around " PTR_FORMAT, p2i(exception));
506         exception->print_on(ls);
507       }
508       return;
509     }
510 
511     // Otherwise wrap the exception in a BootstrapMethodError
512     if (ls != nullptr) {
513       ResourceMark rm(THREAD);
514       ls->print_cr("%s throws BSME for " PTR_FORMAT, is_indy ? "invokedynamic" : "dynamic constant", p2i(exception));
515       exception->print_on(ls);
516     }
517     Handle nested_exception(THREAD, exception);
518     THREAD->clear_pending_exception();
519     THROW_CAUSE(vmSymbols::java_lang_BootstrapMethodError(), nested_exception)
520   }
521 }
522 
523 // Exception counting for hs_err file
524 Atomic<int> Exceptions::_stack_overflow_errors{0};
525 Atomic<int> Exceptions::_linkage_errors{0};
526 Atomic<int> Exceptions::_out_of_memory_error_java_heap_errors{0};
527 Atomic<int> Exceptions::_out_of_memory_error_metaspace_errors{0};
528 Atomic<int> Exceptions::_out_of_memory_error_class_metaspace_errors{0};
529 
530 void Exceptions::count_out_of_memory_exceptions(Handle exception) {
531   if (Universe::is_out_of_memory_error_metaspace(exception())) {
532     _out_of_memory_error_metaspace_errors.add_then_fetch(1, memory_order_relaxed);
533   } else if (Universe::is_out_of_memory_error_class_metaspace(exception())) {
534     _out_of_memory_error_class_metaspace_errors.add_then_fetch(1, memory_order_relaxed);
535   } else {
536     // everything else reported as java heap OOM
537     _out_of_memory_error_java_heap_errors.add_then_fetch(1, memory_order_relaxed);
538   }
539 }
540 
541 static void print_oom_count(outputStream* st, const char *err, int count) {
542   if (count > 0) {
543     st->print_cr("OutOfMemoryError %s=%d", err, count);
544   }
545 }
546 
547 bool Exceptions::has_exception_counts() {
548   return (_stack_overflow_errors.load_relaxed() +
549           _out_of_memory_error_java_heap_errors.load_relaxed() +
550           _out_of_memory_error_metaspace_errors.load_relaxed() +
551           _out_of_memory_error_class_metaspace_errors.load_relaxed()) > 0;
552 }
553 
554 void Exceptions::print_exception_counts_on_error(outputStream* st) {
555   print_oom_count(st, "java_heap_errors",
556                   _out_of_memory_error_java_heap_errors.load_relaxed());
557   print_oom_count(st, "metaspace_errors",
558                   _out_of_memory_error_metaspace_errors.load_relaxed());
559   print_oom_count(st, "class_metaspace_errors",
560                   _out_of_memory_error_class_metaspace_errors.load_relaxed());
561   if (_stack_overflow_errors.load_relaxed() > 0) {
562     st->print_cr("StackOverflowErrors=%d", _stack_overflow_errors.load_relaxed());
563   }
564   if (_linkage_errors.load_relaxed() > 0) {
565     st->print_cr("LinkageErrors=%d", _linkage_errors.load_relaxed());
566   }
567 }
568 
569 // Implementation of ExceptionMark
570 
571 ExceptionMark::ExceptionMark(JavaThread* thread) {
572   assert(thread == JavaThread::current(), "must be");
573   _thread  = thread;
574   check_no_pending_exception();
575 }
576 
577 ExceptionMark::ExceptionMark() {
578   _thread = JavaThread::current();
579   check_no_pending_exception();
580 }
581 
582 inline void ExceptionMark::check_no_pending_exception() {
583   if (_thread->has_pending_exception()) {
584     oop exception = _thread->pending_exception();
585     _thread->clear_pending_exception(); // Needed to avoid infinite recursion
586     ResourceMark rm;
587     exception->print();
588     fatal("ExceptionMark constructor expects no pending exceptions");
589   }
590 }
591 
592 extern bool is_vm_created();
593 
594 ExceptionMark::~ExceptionMark() {
595   if (_thread->has_pending_exception()) {
596     Handle exception(_thread, _thread->pending_exception());
597     _thread->clear_pending_exception(); // Needed to avoid infinite recursion
598     if (is_vm_created()) {
599       ResourceMark rm;
600       exception->print();
601       fatal("ExceptionMark destructor expects no pending exceptions");
602     } else {
603       vm_exit_during_initialization(exception);
604     }
605   }
606 }
607 
608 // ----------------------------------------------------------------------------------------
609 
610 // caller frees value_string if necessary
611 void Exceptions::debug_check_abort(const char *value_string, const char* message) {
612   if (AbortVMOnException != nullptr && value_string != nullptr &&
613       strstr(value_string, AbortVMOnException)) {
614     if (AbortVMOnExceptionMessage == nullptr || (message != nullptr &&
615         strstr(message, AbortVMOnExceptionMessage))) {
616       if (message == nullptr) {
617         fatal("Saw %s, aborting", value_string);
618       } else {
619         fatal("Saw %s: %s, aborting", value_string, message);
620       }
621     }
622   }
623 }
624 
625 void Exceptions::debug_check_abort(Handle exception, const char* message) {
626   if (AbortVMOnException != nullptr) {
627     debug_check_abort_helper(exception, message);
628   }
629 }
630 
631 void Exceptions::debug_check_abort_helper(Handle exception, const char* message) {
632   ResourceMark rm;
633   if (message == nullptr && exception->is_a(vmClasses::Throwable_klass())) {
634     oop msg = java_lang_Throwable::message(exception());
635     if (msg != nullptr) {
636       message = java_lang_String::as_utf8_string(msg);
637     }
638   }
639   debug_check_abort(exception()->klass()->external_name(), message);
640 }
641 
642 // for logging exceptions
643 void Exceptions::log_exception(Handle exception, const char* message) {
644   ResourceMark rm;
645   const char* detail_message = java_lang_Throwable::message_as_utf8(exception());
646   if (detail_message != nullptr) {
647     log_info(exceptions)("Exception <%.*s: %.*s>\n thrown in %.*s",
648                          MAX_LEN, exception->print_value_string(),
649                          MAX_LEN, detail_message,
650                          MAX_LEN, message);
651   } else {
652     log_info(exceptions)("Exception <%.*s>\n thrown in %.*s",
653                          MAX_LEN, exception->print_value_string(),
654                          MAX_LEN, message);
655   }
656 }
657 
658 // This is called from InterpreterRuntime::exception_handler_for_exception(), which is the only
659 // easy way to be notified in the VM that an _athrow bytecode has been executed. (The alternative
660 // would be to add hooks into the interpreter and compiler, for all platforms ...).
661 //
662 // Unfortunately, InterpreterRuntime::exception_handler_for_exception() is called for every level
663 // of the Java stack when looking for an exception handler. To avoid excessive output,
664 // we print the stack only when the bci points to an _athrow bytecode.
665 //
666 // NOTE: exceptions that are NOT thrown by _athrow are handled by Exceptions::special_exception()
667 // and Exceptions::_throw()).
668 void Exceptions::log_exception_stacktrace(Handle exception, methodHandle method, int bci) {
669   if (!method->is_native() && (Bytecodes::Code) *method->bcp_from(bci) == Bytecodes::_athrow) {
670     // TODO: try to find a way to avoid repeated stacktraces when an exception gets re-thrown
671     // by a finally block
672     log_exception_stacktrace(exception);
673   }
674 }
675 
676 // This should be called only from a live Java thread.
677 void Exceptions::log_exception_stacktrace(Handle exception) {
678   LogStreamHandle(Info, exceptions, stacktrace) st;
679   ResourceMark rm;
680   const char* detail_message = java_lang_Throwable::message_as_utf8(exception());
681   if (detail_message != nullptr) {
682     st.print_cr("Exception <%.*s: %.*s>",
683                 MAX_LEN, exception->print_value_string(),
684                 MAX_LEN, detail_message);
685   } else {
686     st.print_cr("Exception <%.*s>",
687                 MAX_LEN, exception->print_value_string());
688   }
689   JavaThread* t = JavaThread::current();
690   if (t->has_last_Java_frame()) {
691     t->print_active_stack_on(&st);
692   } else {
693     st.print_cr("(Cannot print stracktrace)");
694   }
695 }