aoqi@0: /* aoqi@0: * Copyright (c) 1998, 2014, Oracle and/or its affiliates. All rights reserved. aoqi@0: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. aoqi@0: * aoqi@0: * This code is free software; you can redistribute it and/or modify it aoqi@0: * under the terms of the GNU General Public License version 2 only, as aoqi@0: * published by the Free Software Foundation. aoqi@0: * aoqi@0: * This code is distributed in the hope that it will be useful, but WITHOUT aoqi@0: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or aoqi@0: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License aoqi@0: * version 2 for more details (a copy is included in the LICENSE file that aoqi@0: * accompanied this code). aoqi@0: * aoqi@0: * You should have received a copy of the GNU General Public License version aoqi@0: * 2 along with this work; if not, write to the Free Software Foundation, aoqi@0: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. aoqi@0: * aoqi@0: * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA aoqi@0: * or visit www.oracle.com if you need additional information or have any aoqi@0: * questions. aoqi@0: * aoqi@0: */ aoqi@0: aoqi@0: #ifndef SHARE_VM_UTILITIES_EXCEPTIONS_HPP aoqi@0: #define SHARE_VM_UTILITIES_EXCEPTIONS_HPP aoqi@0: aoqi@0: #include "memory/allocation.hpp" aoqi@0: #include "oops/oopsHierarchy.hpp" aoqi@0: #include "utilities/sizes.hpp" aoqi@0: aoqi@0: // This file provides the basic support for exception handling in the VM. aoqi@0: // Note: We do not use C++ exceptions to avoid compiler dependencies and aoqi@0: // unpredictable performance. aoqi@0: // aoqi@0: // Scheme: Exceptions are stored with the thread. There is never more aoqi@0: // than one pending exception per thread. All functions that can throw aoqi@0: // an exception carry a THREAD argument (usually the last argument and aoqi@0: // declared with the TRAPS macro). Throwing an exception means setting aoqi@0: // a pending exception in the thread. Upon return from a function that aoqi@0: // can throw an exception, we must check if an exception is pending. aoqi@0: // The CHECK macros do this in a convenient way. Carrying around the aoqi@0: // thread provides also convenient access to it (e.g. for Handle aoqi@0: // creation, w/o the need for recomputation). aoqi@0: aoqi@0: aoqi@0: aoqi@0: // Forward declarations to be independent of the include structure. aoqi@0: // This allows us to have exceptions.hpp included in top.hpp. aoqi@0: aoqi@0: class Thread; aoqi@0: class Handle; aoqi@0: class Symbol; aoqi@0: class JavaCallArguments; aoqi@0: aoqi@0: // The ThreadShadow class is a helper class to access the _pending_exception aoqi@0: // field of the Thread class w/o having access to the Thread's interface (for aoqi@0: // include hierachy reasons). aoqi@0: aoqi@0: class ThreadShadow: public CHeapObj { aoqi@0: friend class VMStructs; aoqi@0: aoqi@0: protected: aoqi@0: oop _pending_exception; // Thread has gc actions. aoqi@0: const char* _exception_file; // file information for exception (debugging only) aoqi@0: int _exception_line; // line information for exception (debugging only) aoqi@0: friend void check_ThreadShadow(); // checks _pending_exception offset aoqi@0: aoqi@0: // The following virtual exists only to force creation of a vtable. aoqi@0: // We need ThreadShadow to have a vtable, even in product builds, aoqi@0: // so that its layout will start at an offset of zero relative to Thread. aoqi@0: // Some C++ compilers are so "clever" that they put the ThreadShadow aoqi@0: // base class at offset 4 in Thread (after Thread's vtable), if they aoqi@0: // notice that Thread has a vtable but ThreadShadow does not. aoqi@0: virtual void unused_initial_virtual() { } aoqi@0: aoqi@0: public: aoqi@0: oop pending_exception() const { return _pending_exception; } aoqi@0: bool has_pending_exception() const { return _pending_exception != NULL; } aoqi@0: const char* exception_file() const { return _exception_file; } aoqi@0: int exception_line() const { return _exception_line; } aoqi@0: aoqi@0: // Code generation support aoqi@0: static ByteSize pending_exception_offset() { return byte_offset_of(ThreadShadow, _pending_exception); } aoqi@0: aoqi@0: // use THROW whenever possible! aoqi@0: void set_pending_exception(oop exception, const char* file, int line); aoqi@0: aoqi@0: // use CLEAR_PENDING_EXCEPTION whenever possible! aoqi@0: void clear_pending_exception(); aoqi@0: aoqi@0: ThreadShadow() : _pending_exception(NULL), aoqi@0: _exception_file(NULL), _exception_line(0) {} aoqi@0: }; aoqi@0: aoqi@0: aoqi@0: // Exceptions is a helper class that encapsulates all operations aoqi@0: // that require access to the thread interface and which are aoqi@0: // relatively rare. The Exceptions operations should only be aoqi@0: // used directly if the macros below are insufficient. aoqi@0: aoqi@0: class Exceptions { aoqi@0: static bool special_exception(Thread *thread, const char* file, int line, Handle exception); aoqi@0: static bool special_exception(Thread* thread, const char* file, int line, Symbol* name, const char* message); aoqi@0: public: aoqi@0: // this enum is defined to indicate whether it is safe to aoqi@0: // ignore the encoding scheme of the original message string. aoqi@0: typedef enum { aoqi@0: safe_to_utf8 = 0, aoqi@0: unsafe_to_utf8 = 1 aoqi@0: } ExceptionMsgToUtf8Mode; aoqi@0: // Throw exceptions: w/o message, w/ message & with formatted message. aoqi@0: static void _throw_oop(Thread* thread, const char* file, int line, oop exception); aoqi@0: static void _throw(Thread* thread, const char* file, int line, Handle exception, const char* msg = NULL); aoqi@0: aoqi@0: static void _throw_msg(Thread* thread, const char* file, int line, Symbol* name, const char* message); aoqi@0: static void _throw_msg(Thread* thread, const char* file, int line, Symbol* name, const char* message, aoqi@0: Handle loader, Handle protection_domain); aoqi@0: aoqi@0: static void _throw_msg_cause(Thread* thread, const char* file, int line, Symbol* name, const char* message, Handle h_cause); aoqi@0: static void _throw_msg_cause(Thread* thread, const char* file, int line, Symbol* name, const char* message, Handle h_cause, aoqi@0: Handle h_loader, Handle h_protection_domain); aoqi@0: aoqi@0: static void _throw_cause(Thread* thread, const char* file, int line, Symbol* name, Handle h_cause); aoqi@0: static void _throw_cause(Thread* thread, const char* file, int line, Symbol* name, Handle h_cause, aoqi@0: Handle h_loader, Handle h_protection_domain); aoqi@0: aoqi@0: static void _throw_args(Thread* thread, const char* file, int line, aoqi@0: Symbol* name, Symbol* signature, aoqi@0: JavaCallArguments* args); aoqi@0: aoqi@0: // There is no THROW... macro for this method. Caller should remember aoqi@0: // to do a return after calling it. aoqi@0: static void fthrow(Thread* thread, const char* file, int line, Symbol* name, aoqi@0: const char* format, ...) ATTRIBUTE_PRINTF(5, 6); aoqi@0: aoqi@0: // Create and initialize a new exception aoqi@0: static Handle new_exception(Thread* thread, Symbol* name, aoqi@0: Symbol* signature, JavaCallArguments* args, aoqi@0: Handle loader, Handle protection_domain); aoqi@0: aoqi@0: static Handle new_exception(Thread* thread, Symbol* name, aoqi@0: Symbol* signature, JavaCallArguments* args, aoqi@0: Handle cause, aoqi@0: Handle loader, Handle protection_domain); aoqi@0: aoqi@0: static Handle new_exception(Thread* thread, Symbol* name, aoqi@0: Handle cause, aoqi@0: Handle loader, Handle protection_domain, aoqi@0: ExceptionMsgToUtf8Mode to_utf8_safe = safe_to_utf8); aoqi@0: aoqi@0: static Handle new_exception(Thread* thread, Symbol* name, aoqi@0: const char* message, Handle cause, aoqi@0: Handle loader, Handle protection_domain, aoqi@0: ExceptionMsgToUtf8Mode to_utf8_safe = safe_to_utf8); aoqi@0: aoqi@0: static Handle new_exception(Thread* thread, Symbol* name, aoqi@0: const char* message, aoqi@0: ExceptionMsgToUtf8Mode to_utf8_safe = safe_to_utf8); aoqi@0: aoqi@0: static void throw_stack_overflow_exception(Thread* thread, const char* file, int line, methodHandle method); aoqi@0: aoqi@0: // for AbortVMOnException flag aoqi@0: NOT_PRODUCT(static void debug_check_abort(Handle exception, const char* message = NULL);) aoqi@0: NOT_PRODUCT(static void debug_check_abort(const char *value_string, const char* message = NULL);) aoqi@0: }; aoqi@0: aoqi@0: aoqi@0: // The THREAD & TRAPS macros facilitate the declaration of functions that throw exceptions. aoqi@0: // Convention: Use the TRAPS macro as the last argument of such a function; e.g.: aoqi@0: // aoqi@0: // int this_function_may_trap(int x, float y, TRAPS) aoqi@0: aoqi@0: #define THREAD __the_thread__ aoqi@0: #define TRAPS Thread* THREAD aoqi@0: aoqi@0: aoqi@0: // The CHECK... macros should be used to pass along a THREAD reference and to check for pending aoqi@0: // exceptions. In special situations it is necessary to handle pending exceptions explicitly, aoqi@0: // in these cases the PENDING_EXCEPTION helper macros should be used. aoqi@0: // aoqi@0: // Macro naming conventions: Macros that end with _ require a result value to be returned. They aoqi@0: // are for functions with non-void result type. The result value is usually ignored because of aoqi@0: // the exception and is only needed for syntactic correctness. The _0 ending is a shortcut for aoqi@0: // _(0) since this is a frequent case. Example: aoqi@0: // aoqi@0: // int result = this_function_may_trap(x_arg, y_arg, CHECK_0); aoqi@0: // aoqi@0: // CAUTION: make sure that the function call using a CHECK macro is not the only statement of a aoqi@0: // conditional branch w/o enclosing {} braces, since the CHECK macros expand into several state- aoqi@0: // ments! aoqi@0: aoqi@0: #define PENDING_EXCEPTION (((ThreadShadow*)THREAD)->pending_exception()) aoqi@0: #define HAS_PENDING_EXCEPTION (((ThreadShadow*)THREAD)->has_pending_exception()) aoqi@0: #define CLEAR_PENDING_EXCEPTION (((ThreadShadow*)THREAD)->clear_pending_exception()) aoqi@0: aoqi@0: #define CHECK THREAD); if (HAS_PENDING_EXCEPTION) return ; (void)(0 aoqi@0: #define CHECK_(result) THREAD); if (HAS_PENDING_EXCEPTION) return result; (void)(0 aoqi@0: #define CHECK_0 CHECK_(0) aoqi@0: #define CHECK_NH CHECK_(Handle()) aoqi@0: #define CHECK_NULL CHECK_(NULL) aoqi@0: #define CHECK_false CHECK_(false) aoqi@0: aoqi@0: #define CHECK_AND_CLEAR THREAD); if (HAS_PENDING_EXCEPTION) { CLEAR_PENDING_EXCEPTION; return; } (void)(0 aoqi@0: #define CHECK_AND_CLEAR_(result) THREAD); if (HAS_PENDING_EXCEPTION) { CLEAR_PENDING_EXCEPTION; return result; } (void)(0 aoqi@0: #define CHECK_AND_CLEAR_0 CHECK_AND_CLEAR_(0) aoqi@0: #define CHECK_AND_CLEAR_NH CHECK_AND_CLEAR_(Handle()) aoqi@0: #define CHECK_AND_CLEAR_NULL CHECK_AND_CLEAR_(NULL) aoqi@0: #define CHECK_AND_CLEAR_false CHECK_AND_CLEAR_(false) aoqi@0: aoqi@0: // The THROW... macros should be used to throw an exception. They require a THREAD variable to be aoqi@0: // visible within the scope containing the THROW. Usually this is achieved by declaring the function aoqi@0: // with a TRAPS argument. aoqi@0: aoqi@0: #define THREAD_AND_LOCATION THREAD, __FILE__, __LINE__ aoqi@0: aoqi@0: #define THROW_OOP(e) \ aoqi@0: { Exceptions::_throw_oop(THREAD_AND_LOCATION, e); return; } aoqi@0: aoqi@0: #define THROW_HANDLE(e) \ aoqi@0: { Exceptions::_throw(THREAD_AND_LOCATION, e); return; } aoqi@0: aoqi@0: #define THROW(name) \ aoqi@0: { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, NULL); return; } aoqi@0: aoqi@0: #define THROW_MSG(name, message) \ aoqi@0: { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, message); return; } aoqi@0: aoqi@0: #define THROW_CAUSE(name, cause) \ aoqi@0: { Exceptions::_throw_cause(THREAD_AND_LOCATION, name, cause); return; } aoqi@0: aoqi@0: #define THROW_MSG_LOADER(name, message, loader, protection_domain) \ aoqi@0: { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, message, loader, protection_domain); return; } aoqi@0: aoqi@0: #define THROW_ARG(name, signature, args) \ aoqi@0: { Exceptions::_throw_args(THREAD_AND_LOCATION, name, signature, args); return; } aoqi@0: aoqi@0: #define THROW_OOP_(e, result) \ aoqi@0: { Exceptions::_throw_oop(THREAD_AND_LOCATION, e); return result; } aoqi@0: aoqi@0: #define THROW_HANDLE_(e, result) \ aoqi@0: { Exceptions::_throw(THREAD_AND_LOCATION, e); return result; } aoqi@0: aoqi@0: #define THROW_(name, result) \ aoqi@0: { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, NULL); return result; } aoqi@0: aoqi@0: #define THROW_MSG_(name, message, result) \ aoqi@0: { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, message); return result; } aoqi@0: aoqi@0: #define THROW_MSG_LOADER_(name, message, loader, protection_domain, result) \ aoqi@0: { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, message, loader, protection_domain); return result; } aoqi@0: aoqi@0: #define THROW_ARG_(name, signature, args, result) \ aoqi@0: { Exceptions::_throw_args(THREAD_AND_LOCATION, name, signature, args); return result; } aoqi@0: aoqi@0: #define THROW_MSG_CAUSE(name, message, cause) \ aoqi@0: { Exceptions::_throw_msg_cause(THREAD_AND_LOCATION, name, message, cause); return; } aoqi@0: aoqi@0: #define THROW_MSG_CAUSE_(name, message, cause, result) \ aoqi@0: { Exceptions::_throw_msg_cause(THREAD_AND_LOCATION, name, message, cause); return result; } aoqi@0: aoqi@0: aoqi@0: #define THROW_OOP_0(e) THROW_OOP_(e, 0) aoqi@0: #define THROW_HANDLE_0(e) THROW_HANDLE_(e, 0) aoqi@0: #define THROW_0(name) THROW_(name, 0) aoqi@0: #define THROW_MSG_0(name, message) THROW_MSG_(name, message, 0) aoqi@0: #define THROW_WRAPPED_0(name, oop_to_wrap) THROW_WRAPPED_(name, oop_to_wrap, 0) aoqi@0: #define THROW_ARG_0(name, signature, arg) THROW_ARG_(name, signature, arg, 0) aoqi@0: #define THROW_MSG_CAUSE_0(name, message, cause) THROW_MSG_CAUSE_(name, message, cause, 0) aoqi@0: #define THROW_MSG_CAUSE_NULL(name, message, cause) THROW_MSG_CAUSE_(name, message, cause, NULL) aoqi@0: aoqi@0: #define THROW_NULL(name) THROW_(name, NULL) aoqi@0: #define THROW_MSG_NULL(name, message) THROW_MSG_(name, message, NULL) aoqi@0: aoqi@0: // The CATCH macro checks that no exception has been thrown by a function; it is used at aoqi@0: // call sites about which is statically known that the callee cannot throw an exception aoqi@0: // even though it is declared with TRAPS. aoqi@0: aoqi@0: #define CATCH \ aoqi@0: THREAD); if (HAS_PENDING_EXCEPTION) { \ aoqi@0: oop ex = PENDING_EXCEPTION; \ aoqi@0: CLEAR_PENDING_EXCEPTION; \ aoqi@0: ex->print(); \ aoqi@0: ShouldNotReachHere(); \ aoqi@0: } (void)(0 aoqi@0: aoqi@0: // ExceptionMark is a stack-allocated helper class for local exception handling. aoqi@0: // It is used with the EXCEPTION_MARK macro. aoqi@0: aoqi@0: class ExceptionMark { aoqi@0: private: aoqi@0: Thread* _thread; aoqi@0: aoqi@0: public: aoqi@0: ExceptionMark(Thread*& thread); aoqi@0: ~ExceptionMark(); aoqi@0: }; aoqi@0: aoqi@0: aoqi@0: aoqi@0: // Use an EXCEPTION_MARK for 'local' exceptions. EXCEPTION_MARK makes sure that no aoqi@0: // pending exception exists upon entering its scope and tests that no pending exception aoqi@0: // exists when leaving the scope. aoqi@0: aoqi@0: // See also preserveException.hpp for PRESERVE_EXCEPTION_MARK macro, aoqi@0: // which preserves pre-existing exceptions and does not allow new aoqi@0: // exceptions. aoqi@0: aoqi@0: #define EXCEPTION_MARK Thread* THREAD = NULL; ExceptionMark __em(THREAD); aoqi@0: aoqi@0: #endif // SHARE_VM_UTILITIES_EXCEPTIONS_HPP