8319851: Improve exception logging

Reviewed-by: mbaesken
Backport-of: 87dfeeb14fdd0fa1648a8bec91b5b713cc2c1b83

Author: martinuy

src/hotspot/share/classfile/javaClasses.cpp

@@ -2073,18 +2073,17 @@ oop java_lang_Throwable::message(oop throwable) {
   return throwable->obj_field(_detailMessage_offset);
 }
 
-oop java_lang_Throwable::cause(oop throwable) {
-  return throwable->obj_field(_cause_offset);
+const char* java_lang_Throwable::message_as_utf8(oop throwable) {
+  oop msg = java_lang_Throwable::message(throwable);
+  const char* msg_utf8 = nullptr;
+  if (msg != nullptr) {
+    msg_utf8 = java_lang_String::as_utf8_string(msg);
+  }
+  return msg_utf8;
 }
 
-// Return Symbol for detailed_message or null
-Symbol* java_lang_Throwable::detail_message(oop throwable) {
-  PreserveExceptionMark pm(Thread::current());
-  oop detailed_message = java_lang_Throwable::message(throwable);
-  if (detailed_message != nullptr) {
-    return java_lang_String::as_symbol(detailed_message);
-  }
-  return nullptr;
+oop java_lang_Throwable::cause(oop throwable) {
+  return throwable->obj_field(_cause_offset);
 }
 
 void java_lang_Throwable::set_message(oop throwable, oop value) {

src/hotspot/share/classfile/javaClasses.hpp

@@ -591,12 +591,14 @@ class java_lang_Throwable: AllStatic {
   static void set_backtrace(oop throwable, oop value);
   static int depth(oop throwable);
   static void set_depth(oop throwable, int value);
-  static int get_detailMessage_offset() { CHECK_INIT(_detailMessage_offset); }
   // Message
+  static int get_detailMessage_offset() { CHECK_INIT(_detailMessage_offset); }
   static oop message(oop throwable);
-  static oop cause(oop throwable);
+  static const char* message_as_utf8(oop throwable);
   static void set_message(oop throwable, oop value);
-  static Symbol* detail_message(oop throwable);
+
+  static oop cause(oop throwable);
+
   static void print_stack_element(outputStream *st, Method* method, int bci);
 
   static void compute_offsets();

src/hotspot/share/classfile/resolutionErrors.cpp

@@ -66,8 +66,8 @@ void ResolutionErrorTable::initialize() {
 
 // create new error entry
 void ResolutionErrorTable::add_entry(const constantPoolHandle& pool, int cp_index,
-                                     Symbol* error, Symbol* message,
-                                     Symbol* cause, Symbol* cause_msg)
+                                     Symbol* error, const char* message,
+                                     Symbol* cause, const char* cause_msg)
 {
   assert_locked_or_safepoint(SystemDictionary_lock);
   assert(!pool.is_null() && error != nullptr, "adding null obj");
@@ -97,26 +97,30 @@ ResolutionErrorEntry* ResolutionErrorTable::find_entry(const constantPoolHandle&
   return entry == nullptr ? nullptr : *entry;
 }
 
-ResolutionErrorEntry::ResolutionErrorEntry(Symbol* error, Symbol* message,
-      Symbol* cause, Symbol* cause_msg):
+ResolutionErrorEntry::ResolutionErrorEntry(Symbol* error, const char* message,
+                                           Symbol* cause, const char* cause_msg):
         _error(error),
-        _message(message),
+        _message(message != nullptr ? os::strdup(message) : nullptr),
         _cause(cause),
-        _cause_msg(cause_msg),
+        _cause_msg(cause_msg != nullptr ? os::strdup(cause_msg) : nullptr),
         _nest_host_error(nullptr) {
 
   Symbol::maybe_increment_refcount(_error);
-  Symbol::maybe_increment_refcount(_message);
   Symbol::maybe_increment_refcount(_cause);
-  Symbol::maybe_increment_refcount(_cause_msg);
 }
 
 ResolutionErrorEntry::~ResolutionErrorEntry() {
   // decrement error refcount
   Symbol::maybe_decrement_refcount(_error);
-  Symbol::maybe_decrement_refcount(_message);
   Symbol::maybe_decrement_refcount(_cause);
-  Symbol::maybe_decrement_refcount(_cause_msg);
+
+  if (_message != nullptr) {
+    FREE_C_HEAP_ARRAY(char, _message);
+  }
+
+  if (_cause_msg != nullptr) {
+    FREE_C_HEAP_ARRAY(char, _cause_msg);
+  }
 
   if (nest_host_error() != nullptr) {
     FREE_C_HEAP_ARRAY(char, nest_host_error());

src/hotspot/share/classfile/resolutionErrors.hpp

@@ -36,10 +36,11 @@ class ResolutionErrorTable : AllStatic {
 
 public:
   static void initialize();
-  static void add_entry(const constantPoolHandle& pool, int which, Symbol* error, Symbol* message,
-                        Symbol* cause, Symbol* cause_msg);
+  static void add_entry(const constantPoolHandle& pool, int cp_index,
+                        Symbol* error, const char* error_msg,
+                        Symbol* cause, const char* cause_msg);
 
-  static void add_entry(const constantPoolHandle& pool, int which, const char* message);
+  static void add_entry(const constantPoolHandle& pool, int cp_index, const char* message);
 
   // find error given the constant pool and constant pool index
   static ResolutionErrorEntry* find_entry(const constantPoolHandle& pool, int cp_index);
@@ -69,34 +70,38 @@ class ResolutionErrorTable : AllStatic {
 class ResolutionErrorEntry : public CHeapObj<mtClass> {
  private:
   Symbol*           _error;
-  Symbol*           _message;
+  const char*       _message;
   Symbol*           _cause;
-  Symbol*           _cause_msg;
+  const char*       _cause_msg;
   const char*       _nest_host_error;
 
   NONCOPYABLE(ResolutionErrorEntry);
 
  public:
-    ResolutionErrorEntry(Symbol* error, Symbol* message, Symbol* cause, Symbol* cause_msg);
+  // The incoming message and cause_msg are copied to the C-Heap.
+  ResolutionErrorEntry(Symbol* error, const char* message,
+                       Symbol* cause, const char* cause_msg);
 
-    ResolutionErrorEntry(const char* message):
+  // The incoming nest host error message is already in the C-Heap.
+  ResolutionErrorEntry(const char* message):
         _error(nullptr),
         _message(nullptr),
         _cause(nullptr),
         _cause_msg(nullptr),
         _nest_host_error(message) {}
 
-    ~ResolutionErrorEntry();
+  ~ResolutionErrorEntry();
 
-    void set_nest_host_error(const char* message) {
-      _nest_host_error = message;
-    }
+  // The incoming nest host error message is already in the C-Heap.
+  void set_nest_host_error(const char* message) {
+    _nest_host_error = message;
+  }
 
 
   Symbol*            error() const              { return _error; }
-  Symbol*            message() const            { return _message; }
+  const char*        message() const            { return _message; }
   Symbol*            cause() const              { return _cause; }
-  Symbol*            cause_msg() const          { return _cause_msg; }
+  const char*        cause_msg() const          { return _cause_msg; }
   const char*        nest_host_error() const    { return _nest_host_error; }
 };
 

src/hotspot/share/classfile/systemDictionary.cpp

@@ -1797,8 +1797,8 @@ bool SystemDictionary::add_loader_constraint(Symbol* class_name,
 // Add entry to resolution error table to record the error when the first
 // attempt to resolve a reference to a class has failed.
 void SystemDictionary::add_resolution_error(const constantPoolHandle& pool, int which,
-                                            Symbol* error, Symbol* message,
-                                            Symbol* cause, Symbol* cause_msg) {
+                                            Symbol* error, const char* message,
+                                            Symbol* cause, const char* cause_msg) {
   {
     MutexLocker ml(Thread::current(), SystemDictionary_lock);
     ResolutionErrorEntry* entry = ResolutionErrorTable::find_entry(pool, which);
@@ -1815,7 +1815,8 @@ void SystemDictionary::delete_resolution_error(ConstantPool* pool) {
 
 // Lookup resolution error table. Returns error if found, otherwise null.
 Symbol* SystemDictionary::find_resolution_error(const constantPoolHandle& pool, int which,
-                                                Symbol** message, Symbol** cause, Symbol** cause_msg) {
+                                                const char** message,
+                                                Symbol** cause, const char** cause_msg) {
 
   {
     MutexLocker ml(Thread::current(), SystemDictionary_lock);

src/hotspot/share/classfile/systemDictionary.hpp

@@ -272,12 +272,13 @@ class SystemDictionary : AllStatic {
 
   // Record the error when the first attempt to resolve a reference from a constant
   // pool entry to a class fails.
-  static void add_resolution_error(const constantPoolHandle& pool, int which, Symbol* error,
-                                   Symbol* message, Symbol* cause = nullptr, Symbol* cause_msg = nullptr);
+  static void add_resolution_error(const constantPoolHandle& pool, int which,
+                                   Symbol* error, const char* message,
+                                   Symbol* cause = nullptr, const char* cause_msg = nullptr);
   static void delete_resolution_error(ConstantPool* pool);
   static Symbol* find_resolution_error(const constantPoolHandle& pool, int which,
-                                       Symbol** message, Symbol** cause, Symbol** cause_msg);
-
+                                       const char** message,
+                                       Symbol** cause, const char** cause_msg);
 
   // Record a nest host resolution/validation error
   static void add_nest_host_error(const constantPoolHandle& pool, int which,

src/hotspot/share/oops/constantPool.cpp

@@ -803,13 +803,16 @@ void ConstantPool::resolve_string_constants_impl(const constantPoolHandle& this_
   }
 }
 
-static Symbol* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
+static const char* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception) {
+  // Note: caller needs ResourceMark
+
   // Dig out the detailed message to reuse if possible
-  Symbol* message = java_lang_Throwable::detail_message(pending_exception);
-  if (message != nullptr) {
-    return message;
+  const char* msg = java_lang_Throwable::message_as_utf8(pending_exception);
+  if (msg != nullptr) {
+    return msg;
   }
 
+  Symbol* message = nullptr;
   // Return specific message for the tag
   switch (tag.value()) {
   case JVM_CONSTANT_UnresolvedClass:
@@ -832,49 +835,48 @@ static Symbol* exception_message(const constantPoolHandle& this_cp, int which, c
     ShouldNotReachHere();
   }
 
-  return message;
+  return message != nullptr ? message->as_C_string() : nullptr;
 }
 
-static void add_resolution_error(const constantPoolHandle& this_cp, int which,
+static void add_resolution_error(JavaThread* current, const constantPoolHandle& this_cp, int which,
                                  constantTag tag, oop pending_exception) {
 
+  ResourceMark rm(current);
   Symbol* error = pending_exception->klass()->name();
   oop cause = java_lang_Throwable::cause(pending_exception);
 
   // Also dig out the exception cause, if present.
   Symbol* cause_sym = nullptr;
-  Symbol* cause_msg = nullptr;
+  const char* cause_msg = nullptr;
   if (cause != nullptr && cause != pending_exception) {
     cause_sym = cause->klass()->name();
-    cause_msg = java_lang_Throwable::detail_message(cause);
+    cause_msg = java_lang_Throwable::message_as_utf8(cause);
   }
 
-  Symbol* message = exception_message(this_cp, which, tag, pending_exception);
+  const char* message = exception_message(this_cp, which, tag, pending_exception);
   SystemDictionary::add_resolution_error(this_cp, which, error, message, cause_sym, cause_msg);
 }
 
 
 void ConstantPool::throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS) {
   ResourceMark rm(THREAD);
-  Symbol* message = nullptr;
+  const char* message = nullptr;
   Symbol* cause = nullptr;
-  Symbol* cause_msg = nullptr;
+  const char* cause_msg = nullptr;
   Symbol* error = SystemDictionary::find_resolution_error(this_cp, which, &message, &cause, &cause_msg);
   assert(error != nullptr, "checking");
-  const char* cause_str = cause_msg != nullptr ? cause_msg->as_C_string() : nullptr;
 
   CLEAR_PENDING_EXCEPTION;
   if (message != nullptr) {
-    char* msg = message->as_C_string();
     if (cause != nullptr) {
-      Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_str);
-      THROW_MSG_CAUSE(error, msg, h_cause);
+      Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
+      THROW_MSG_CAUSE(error, message, h_cause);
     } else {
-      THROW_MSG(error, msg);
+      THROW_MSG(error, message);
     }
   } else {
     if (cause != nullptr) {
-      Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_str);
+      Handle h_cause = Exceptions::new_exception(THREAD, cause, cause_msg);
       THROW_CAUSE(error, h_cause);
     } else {
       THROW(error);
@@ -896,7 +898,7 @@ void ConstantPool::save_and_throw_exception(const constantPoolHandle& this_cp, i
     // and OutOfMemoryError, etc, or if the thread was hit by stop()
     // Needs clarification to section 5.4.3 of the VM spec (see 6308271)
   } else if (this_cp->tag_at(which).value() != error_tag) {
-    add_resolution_error(this_cp, which, tag, PENDING_EXCEPTION);
+    add_resolution_error(THREAD, this_cp, which, tag, PENDING_EXCEPTION);
     // CAS in the tag.  If a thread beat us to registering this error that's fine.
     // If another thread resolved the reference, this is a race condition. This
     // thread may have had a security manager or something temporary.

src/hotspot/share/oops/cpCache.cpp

@@ -849,9 +849,9 @@ bool ConstantPoolCache::save_and_throw_indy_exc(
     CLEAR_PENDING_EXCEPTION;
     return false;
   }
-
+  ResourceMark rm(THREAD);
   Symbol* error = PENDING_EXCEPTION->klass()->name();
-  Symbol* message = java_lang_Throwable::detail_message(PENDING_EXCEPTION);
+  const char* message = java_lang_Throwable::message_as_utf8(PENDING_EXCEPTION);
 
   int encoded_index = ResolutionErrorTable::encode_cpcache_index(
                           ConstantPool::encode_invokedynamic_index(index));

src/hotspot/share/utilities/exceptions.cpp

@@ -565,11 +565,11 @@ void Exceptions::debug_check_abort_helper(Handle exception, const char* message)
 // for logging exceptions
 void Exceptions::log_exception(Handle exception, const char* message) {
   ResourceMark rm;
-  Symbol* detail_message = java_lang_Throwable::detail_message(exception());
+  const char* detail_message = java_lang_Throwable::message_as_utf8(exception());
   if (detail_message != nullptr) {
     log_info(exceptions)("Exception <%s: %s>\n thrown in %s",
                          exception->print_value_string(),
-                         detail_message->as_C_string(),
+                         detail_message,
                          message);
   } else {
     log_info(exceptions)("Exception <%s>\n thrown in %s",