src/share/vm/utilities/exceptions.hpp

Tue, 05 Apr 2011 14:12:31 -0700

author
trims
date
Tue, 05 Apr 2011 14:12:31 -0700
changeset 2708
1d1603768966
parent 2497
3582bf76420e
child 2804
01147d8aac1d
permissions
-rw-r--r--

7010070: Update all 2010 Oracle-changed OpenJDK files to have the proper copyright dates - second pass
Summary: Update the copyright to be 2010 on all changed files in OpenJDK
Reviewed-by: ohair

duke@435 1 /*
trims@2708 2 * Copyright (c) 1998, 2011, Oracle and/or its affiliates. All rights reserved.
duke@435 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435 4 *
duke@435 5 * This code is free software; you can redistribute it and/or modify it
duke@435 6 * under the terms of the GNU General Public License version 2 only, as
duke@435 7 * published by the Free Software Foundation.
duke@435 8 *
duke@435 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@435 13 * accompanied this code).
duke@435 14 *
duke@435 15 * You should have received a copy of the GNU General Public License version
duke@435 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@435 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435 18 *
trims@1907 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907 20 * or visit www.oracle.com if you need additional information or have any
trims@1907 21 * questions.
duke@435 22 *
duke@435 23 */
duke@435 24
stefank@2314 25 #ifndef SHARE_VM_UTILITIES_EXCEPTIONS_HPP
stefank@2314 26 #define SHARE_VM_UTILITIES_EXCEPTIONS_HPP
stefank@2314 27
stefank@2314 28 #include "memory/allocation.hpp"
stefank@2314 29 #include "oops/oopsHierarchy.hpp"
stefank@2314 30 #include "utilities/sizes.hpp"
stefank@2314 31
duke@435 32 // This file provides the basic support for exception handling in the VM.
duke@435 33 // Note: We do not use C++ exceptions to avoid compiler dependencies and
duke@435 34 // unpredictable performance.
duke@435 35 //
duke@435 36 // Scheme: Exceptions are stored with the thread. There is never more
duke@435 37 // than one pending exception per thread. All functions that can throw
duke@435 38 // an exception carry a THREAD argument (usually the last argument and
duke@435 39 // declared with the TRAPS macro). Throwing an exception means setting
duke@435 40 // a pending exception in the thread. Upon return from a function that
duke@435 41 // can throw an exception, we must check if an exception is pending.
duke@435 42 // The CHECK macros do this in a convenient way. Carrying around the
duke@435 43 // thread provides also convenient access to it (e.g. for Handle
duke@435 44 // creation, w/o the need for recomputation).
duke@435 45
duke@435 46
duke@435 47
duke@435 48 // Forward declarations to be independent of the include structure.
duke@435 49 // This allows us to have exceptions.hpp included in top.hpp.
duke@435 50
duke@435 51 class Thread;
duke@435 52 class Handle;
coleenp@2497 53 class Symbol;
duke@435 54 class JavaCallArguments;
duke@435 55
duke@435 56 // The ThreadShadow class is a helper class to access the _pending_exception
duke@435 57 // field of the Thread class w/o having access to the Thread's interface (for
duke@435 58 // include hierachy reasons).
duke@435 59
duke@435 60 class ThreadShadow: public CHeapObj {
duke@435 61 protected:
duke@435 62 oop _pending_exception; // Thread has gc actions.
duke@435 63 const char* _exception_file; // file information for exception (debugging only)
duke@435 64 int _exception_line; // line information for exception (debugging only)
duke@435 65 friend void check_ThreadShadow(); // checks _pending_exception offset
duke@435 66
duke@435 67 // The following virtual exists only to force creation of a vtable.
duke@435 68 // We need ThreadShadow to have a vtable, even in product builds,
duke@435 69 // so that its layout will start at an offset of zero relative to Thread.
duke@435 70 // Some C++ compilers are so "clever" that they put the ThreadShadow
duke@435 71 // base class at offset 4 in Thread (after Thread's vtable), if they
duke@435 72 // notice that Thread has a vtable but ThreadShadow does not.
duke@435 73 virtual void unused_initial_virtual() { }
duke@435 74
duke@435 75 public:
duke@435 76 oop pending_exception() const { return _pending_exception; }
duke@435 77 bool has_pending_exception() const { return _pending_exception != NULL; }
duke@435 78 const char* exception_file() const { return _exception_file; }
duke@435 79 int exception_line() const { return _exception_line; }
duke@435 80
duke@435 81 // Code generation support
duke@435 82 static ByteSize pending_exception_offset() { return byte_offset_of(ThreadShadow, _pending_exception); }
duke@435 83
duke@435 84 // use THROW whenever possible!
duke@435 85 void set_pending_exception(oop exception, const char* file, int line);
duke@435 86
duke@435 87 // use CLEAR_PENDING_EXCEPTION whenever possible!
duke@435 88 void clear_pending_exception();
duke@435 89
duke@435 90 ThreadShadow() : _pending_exception(NULL),
duke@435 91 _exception_file(NULL), _exception_line(0) {}
duke@435 92 };
duke@435 93
duke@435 94
duke@435 95 // Exceptions is a helper class that encapsulates all operations
duke@435 96 // that require access to the thread interface and which are
duke@435 97 // relatively rare. The Exceptions operations should only be
duke@435 98 // used directly if the macros below are insufficient.
duke@435 99
duke@435 100 class Exceptions {
duke@435 101 static bool special_exception(Thread *thread, const char* file, int line, Handle exception);
coleenp@2497 102 static bool special_exception(Thread* thread, const char* file, int line, Symbol* name, const char* message);
duke@435 103 public:
duke@435 104 // this enum is defined to indicate whether it is safe to
duke@435 105 // ignore the encoding scheme of the original message string.
duke@435 106 typedef enum {
duke@435 107 safe_to_utf8 = 0,
duke@435 108 unsafe_to_utf8 = 1
duke@435 109 } ExceptionMsgToUtf8Mode;
duke@435 110 // Throw exceptions: w/o message, w/ message & with formatted message.
duke@435 111 static void _throw_oop(Thread* thread, const char* file, int line, oop exception);
never@1446 112 static void _throw(Thread* thread, const char* file, int line, Handle exception, const char* msg = NULL);
duke@435 113 static void _throw_msg(Thread* thread, const char* file, int line,
coleenp@2497 114 Symbol* name, const char* message, Handle loader,
duke@435 115 Handle protection_domain);
duke@435 116 static void _throw_msg(Thread* thread, const char* file, int line,
coleenp@2497 117 Symbol* name, const char* message);
duke@435 118 static void _throw_args(Thread* thread, const char* file, int line,
coleenp@2497 119 Symbol* name, Symbol* signature,
duke@435 120 JavaCallArguments* args);
duke@435 121 static void _throw_msg_cause(Thread* thread, const char* file,
coleenp@2497 122 int line, Symbol* h_name, const char* message,
duke@435 123 Handle h_cause, Handle h_loader, Handle h_protection_domain);
duke@435 124 static void _throw_msg_cause(Thread* thread, const char* file, int line,
coleenp@2497 125 Symbol* name, const char* message, Handle cause);
duke@435 126
duke@435 127 // There is no THROW... macro for this method. Caller should remember
duke@435 128 // to do a return after calling it.
coleenp@2497 129 static void fthrow(Thread* thread, const char* file, int line, Symbol* name,
duke@435 130 const char* format, ...);
duke@435 131
duke@435 132 // Create and initialize a new exception
coleenp@2497 133 static Handle new_exception(Thread* thread, Symbol* name,
coleenp@2497 134 Symbol* signature, JavaCallArguments* args,
duke@435 135 Handle cause, Handle loader,
duke@435 136 Handle protection_domain);
duke@435 137
coleenp@2497 138 static Handle new_exception(Thread* thread, Symbol* name,
duke@435 139 const char* message, Handle cause, Handle loader,
duke@435 140 Handle protection_domain,
duke@435 141 ExceptionMsgToUtf8Mode to_utf8_safe = safe_to_utf8);
duke@435 142
coleenp@2497 143 static Handle new_exception(Thread* thread, Symbol* name,
duke@435 144 const char* message,
duke@435 145 ExceptionMsgToUtf8Mode to_utf8_safe = safe_to_utf8);
duke@435 146
duke@435 147 static void throw_stack_overflow_exception(Thread* thread, const char* file, int line);
duke@435 148
duke@435 149 // for AbortVMOnException flag
kvn@2039 150 NOT_PRODUCT(static void debug_check_abort(Handle exception, const char* message = NULL);)
kvn@2039 151 NOT_PRODUCT(static void debug_check_abort(const char *value_string, const char* message = NULL);)
duke@435 152 };
duke@435 153
duke@435 154
duke@435 155 // The THREAD & TRAPS macros facilitate the declaration of functions that throw exceptions.
duke@435 156 // Convention: Use the TRAPS macro as the last argument of such a function; e.g.:
duke@435 157 //
duke@435 158 // int this_function_may_trap(int x, float y, TRAPS)
duke@435 159
duke@435 160 #define THREAD __the_thread__
duke@435 161 #define TRAPS Thread* THREAD
duke@435 162
duke@435 163
duke@435 164 // The CHECK... macros should be used to pass along a THREAD reference and to check for pending
duke@435 165 // exceptions. In special situations it is necessary to handle pending exceptions explicitly,
duke@435 166 // in these cases the PENDING_EXCEPTION helper macros should be used.
duke@435 167 //
duke@435 168 // Macro naming conventions: Macros that end with _ require a result value to be returned. They
duke@435 169 // are for functions with non-void result type. The result value is usually ignored because of
duke@435 170 // the exception and is only needed for syntactic correctness. The _0 ending is a shortcut for
duke@435 171 // _(0) since this is a frequent case. Example:
duke@435 172 //
duke@435 173 // int result = this_function_may_trap(x_arg, y_arg, CHECK_0);
duke@435 174 //
duke@435 175 // CAUTION: make sure that the function call using a CHECK macro is not the only statement of a
duke@435 176 // conditional branch w/o enclosing {} braces, since the CHECK macros expand into several state-
duke@435 177 // ments!
duke@435 178
duke@435 179 #define PENDING_EXCEPTION (((ThreadShadow*)THREAD)->pending_exception())
duke@435 180 #define HAS_PENDING_EXCEPTION (((ThreadShadow*)THREAD)->has_pending_exception())
duke@435 181 #define CLEAR_PENDING_EXCEPTION (((ThreadShadow*)THREAD)->clear_pending_exception())
duke@435 182
duke@435 183 #define CHECK THREAD); if (HAS_PENDING_EXCEPTION) return ; (0
duke@435 184 #define CHECK_(result) THREAD); if (HAS_PENDING_EXCEPTION) return result; (0
duke@435 185 #define CHECK_0 CHECK_(0)
duke@435 186 #define CHECK_NH CHECK_(Handle())
duke@435 187 #define CHECK_NULL CHECK_(NULL)
duke@435 188 #define CHECK_false CHECK_(false)
duke@435 189
duke@435 190 // The THROW... macros should be used to throw an exception. They require a THREAD variable to be
duke@435 191 // visible within the scope containing the THROW. Usually this is achieved by declaring the function
duke@435 192 // with a TRAPS argument.
duke@435 193
duke@435 194 #define THREAD_AND_LOCATION THREAD, __FILE__, __LINE__
duke@435 195
duke@435 196 #define THROW_OOP(e) \
duke@435 197 { Exceptions::_throw_oop(THREAD_AND_LOCATION, e); return; }
duke@435 198
duke@435 199 #define THROW_HANDLE(e) \
duke@435 200 { Exceptions::_throw(THREAD_AND_LOCATION, e); return; }
duke@435 201
duke@435 202 #define THROW(name) \
duke@435 203 { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, NULL); return; }
duke@435 204
duke@435 205 #define THROW_MSG(name, message) \
duke@435 206 { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, message); return; }
duke@435 207
duke@435 208 #define THROW_MSG_LOADER(name, message, loader, protection_domain) \
duke@435 209 { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, message, loader, protection_domain); return; }
duke@435 210
duke@435 211 #define THROW_ARG(name, signature, args) \
duke@435 212 { Exceptions::_throw_args(THREAD_AND_LOCATION, name, signature, args); return; }
duke@435 213
duke@435 214 #define THROW_OOP_(e, result) \
duke@435 215 { Exceptions::_throw_oop(THREAD_AND_LOCATION, e); return result; }
duke@435 216
duke@435 217 #define THROW_HANDLE_(e, result) \
duke@435 218 { Exceptions::_throw(THREAD_AND_LOCATION, e); return result; }
duke@435 219
duke@435 220 #define THROW_(name, result) \
duke@435 221 { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, NULL); return result; }
duke@435 222
duke@435 223 #define THROW_MSG_(name, message, result) \
duke@435 224 { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, message); return result; }
duke@435 225
duke@435 226 #define THROW_MSG_LOADER_(name, message, loader, protection_domain, result) \
duke@435 227 { Exceptions::_throw_msg(THREAD_AND_LOCATION, name, message, loader, protection_domain); return result; }
duke@435 228
duke@435 229 #define THROW_ARG_(name, signature, args, result) \
duke@435 230 { Exceptions::_throw_args(THREAD_AND_LOCATION, name, signature, args); return result; }
duke@435 231
duke@435 232 #define THROW_MSG_CAUSE_(name, message, cause, result) \
duke@435 233 { Exceptions::_throw_msg_cause(THREAD_AND_LOCATION, name, message, cause); return result; }
duke@435 234
duke@435 235
duke@435 236 #define THROW_OOP_0(e) THROW_OOP_(e, 0)
duke@435 237 #define THROW_HANDLE_0(e) THROW_HANDLE_(e, 0)
duke@435 238 #define THROW_0(name) THROW_(name, 0)
duke@435 239 #define THROW_MSG_0(name, message) THROW_MSG_(name, message, 0)
duke@435 240 #define THROW_WRAPPED_0(name, oop_to_wrap) THROW_WRAPPED_(name, oop_to_wrap, 0)
duke@435 241 #define THROW_ARG_0(name, signature, arg) THROW_ARG_(name, signature, arg, 0)
duke@435 242 #define THROW_MSG_CAUSE_0(name, message, cause) THROW_MSG_CAUSE_(name, message, cause, 0)
duke@435 243
jrose@1145 244 #define THROW_NULL(name) THROW_(name, NULL)
jrose@1145 245 #define THROW_MSG_NULL(name, message) THROW_MSG_(name, message, NULL)
jrose@1145 246
duke@435 247 // The CATCH macro checks that no exception has been thrown by a function; it is used at
duke@435 248 // call sites about which is statically known that the callee cannot throw an exception
duke@435 249 // even though it is declared with TRAPS.
duke@435 250
duke@435 251 #define CATCH \
duke@435 252 THREAD); if (HAS_PENDING_EXCEPTION) { \
duke@435 253 oop ex = PENDING_EXCEPTION; \
duke@435 254 CLEAR_PENDING_EXCEPTION; \
duke@435 255 ex->print(); \
duke@435 256 ShouldNotReachHere(); \
duke@435 257 } (0
duke@435 258
duke@435 259
duke@435 260 // ExceptionMark is a stack-allocated helper class for local exception handling.
duke@435 261 // It is used with the EXCEPTION_MARK macro.
duke@435 262
duke@435 263 class ExceptionMark {
duke@435 264 private:
duke@435 265 Thread* _thread;
duke@435 266
duke@435 267 public:
duke@435 268 ExceptionMark(Thread*& thread);
duke@435 269 ~ExceptionMark();
duke@435 270 };
duke@435 271
duke@435 272
duke@435 273
duke@435 274 // Use an EXCEPTION_MARK for 'local' exceptions. EXCEPTION_MARK makes sure that no
duke@435 275 // pending exception exists upon entering its scope and tests that no pending exception
duke@435 276 // exists when leaving the scope.
duke@435 277
duke@435 278 // See also preserveException.hpp for PRESERVE_EXCEPTION_MARK macro,
duke@435 279 // which preserves pre-existing exceptions and does not allow new
duke@435 280 // exceptions.
duke@435 281
duke@435 282 #define EXCEPTION_MARK Thread* THREAD; ExceptionMark __em(THREAD);
stefank@2314 283
stefank@2314 284 #endif // SHARE_VM_UTILITIES_EXCEPTIONS_HPP

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