| /* |
| * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #ifndef SHARE_UTILITIES_DEBUG_HPP |
| #define SHARE_UTILITIES_DEBUG_HPP |
| |
| #include "utilities/attributeNoreturn.hpp" |
| #include "utilities/breakpoint.hpp" |
| #include "utilities/compilerWarnings.hpp" |
| #include "utilities/macros.hpp" |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| class oopDesc; |
| |
| // ShowRegistersOnAssert support (for now Linux only) |
| #if defined(LINUX) && !defined(ZERO) |
| #define CAN_SHOW_REGISTERS_ON_ASSERT |
| extern char* g_assert_poison; |
| #define TOUCH_ASSERT_POISON (*g_assert_poison) = 'X'; |
| void initialize_assert_poison(); |
| void disarm_assert_poison(); |
| bool handle_assert_poison_fault(const void* ucVoid, const void* faulting_address); |
| #else |
| #define TOUCH_ASSERT_POISON |
| #endif // CAN_SHOW_REGISTERS_ON_ASSERT |
| |
| // The DebuggingContext class provides a mechanism for temporarily disabling |
| // asserts and various consistency checks. Ordinarily that would be a really |
| // bad idea, but it's essential for some of the debugging commands provided by |
| // HotSpot. (See the Command class in debug.cpp.) These commands are intended |
| // to be invoked from the debugger while the program is otherwise stopped. |
| // The commands may invoke operations while the program is in a state where |
| // those operations are not normally permitted, with the state checked by an |
| // assert. We want the debugging commands to bypass those checks. |
| class DebuggingContext { |
| static int _enabled; // Nesting counter. |
| |
| public: |
| DebuggingContext(); |
| ~DebuggingContext(); |
| // Asserts and other code use this to determine whether to bypass checks |
| // that would otherwise lead to program termination. |
| static bool is_enabled() { return _enabled > 0; } |
| }; |
| |
| // VMASSERT_CHECK_PASSED(P) provides the mechanism by which DebuggingContext |
| // disables asserts. It returns true if P is true or DebuggingContext is |
| // enabled. Assertion failure is reported if it returns false, terminating |
| // the program. |
| // |
| // The DebuggingContext check being enabled isn't placed inside the report |
| // function, as that would prevent the report function from being noreturn. |
| // The report function should be noreturn so there isn't a control path to the |
| // assertion's continuation that has P being false. Otherwise, the compiler |
| // might logically split the continuation to include that path explicitly, |
| // possibly leading to discovering (and warning about) invalid code. For |
| // example, if P := x != nullptr, and the continuation contains a dereference |
| // of x, the compiler might warn because there is a control path (!P -> report |
| // -> continuation) where that dereference is known to be invalid. (Of |
| // course, if execution actually took that path things would go wrong, but |
| // that's the risk the DebuggingContext mechanism takes.) |
| // |
| // Similarly, the check for enabled DebuggingContext shouldn't follow P. |
| // Having this macro expand to `P || DebuggingContext::is_enabled()` has the |
| // same problem of a control path through !P to the assertion's continuation. |
| // |
| // But it can't be just `DebuggingContext::is_enabled() || P` either. That |
| // prevents the compiler from inferring based on P that it is true in the |
| // continuation. But it also prevents the use of assertions in constexpr |
| // contexts, since that expression is not constexpr. |
| // |
| // We could accomodate constexpr usage with std::is_constant_evaluated() (from |
| // C++20). Unfortunately, we don't currently support C++20. However, most |
| // supported compilers have implemented it, and that implementation uses a |
| // compiler intrinsic that we can use directly without otherwise using C++20. |
| // |
| // Note that if we could use std::is_constant_evaluated() then we could just |
| // use this definition for DebuggingContext::is_enabled: |
| // static constexpr bool is_enabled() { |
| // return !std::is_constant_evaluated() && _enabled; |
| // } |
| // The idea being that we are definitely not executing for debugging if doing |
| // constant evaluation in the compiler. We don't do something like that now, |
| // because we need a fallback when we don't have any mechanism for detecting |
| // constant evaluation. |
| #if defined(TARGET_COMPILER_gcc) || defined(TARGET_COMPILER_xlc) |
| |
| // gcc10 added both __has_builtin and __builtin_is_constant_evaluated. |
| // clang has had __has_builtin for a long time, so likely also in xlclang++. |
| // Similarly, clang has had __builtin_is_constant_evaluated for a long time. |
| |
| #ifdef __has_builtin |
| #if __has_builtin(__builtin_is_constant_evaluated) |
| #define VMASSERT_CHECK_PASSED(p) \ |
| ((! __builtin_is_constant_evaluated() && DebuggingContext::is_enabled()) || (p)) |
| #endif |
| #endif |
| |
| #elif defined(TARGET_COMPILER_visCPP) |
| |
| // std::is_constant_evaluated() and it's associated intrinsic are available in |
| // VS 2019 16.5. The minimum supported version of VS 2019 is already past |
| // that, so we can rely on the intrinsic being available. |
| #define VMASSERT_CHECK_PASSED(p) \ |
| ((! __builtin_is_constant_evaluated() && DebuggingContext::is_enabled()) || (p)) |
| |
| #endif // End dispatch on TARGET_COMPILER_xxx |
| |
| // If we don't have a way to detect constant evaluation, then fall back to the |
| // less than ideal form of the check, and hope it works. This succeeds at |
| // least for gcc. The support needed to use the above definition was added in |
| // gcc10. The problems arising from analyzing the failed P case don't seem to |
| // appear until gcc12. An alternative is to not provide DebuggingContext |
| // support for such a configuration. |
| #ifndef VMASSERT_CHECK_PASSED |
| #define VMASSERT_CHECK_PASSED(p) ((p) || DebuggingContext::is_enabled()) |
| #endif |
| |
| // assertions |
| #ifndef ASSERT |
| #define vmassert(p, ...) |
| #else |
| // Note: message says "assert" rather than "vmassert" for backward |
| // compatibility with tools that parse/match the message text. |
| // Note: The signature is vmassert(p, format, ...), but the solaris |
| // compiler can't handle an empty ellipsis in a macro without a warning. |
| #define vmassert(p, ...) \ |
| do { \ |
| if (! VMASSERT_CHECK_PASSED(p)) { \ |
| TOUCH_ASSERT_POISON; \ |
| report_vm_error(__FILE__, __LINE__, "assert(" #p ") failed", __VA_ARGS__); \ |
| } \ |
| } while (0) |
| #endif |
| |
| // For backward compatibility. |
| #define assert(p, ...) vmassert(p, __VA_ARGS__) |
| |
| #define precond(p) assert(p, "precond") |
| #define postcond(p) assert(p, "postcond") |
| |
| #ifndef ASSERT |
| #define vmassert_status(p, status, msg) |
| #else |
| // This version of vmassert is for use with checking return status from |
| // library calls that return actual error values eg. EINVAL, |
| // ENOMEM etc, rather than returning -1 and setting errno. |
| // When the status is not what is expected it is very useful to know |
| // what status was actually returned, so we pass the status variable as |
| // an extra arg and use strerror to convert it to a meaningful string |
| // like "Invalid argument", "out of memory" etc |
| #define vmassert_status(p, status, msg) \ |
| do { \ |
| if (! VMASSERT_CHECK_PASSED(p)) { \ |
| TOUCH_ASSERT_POISON; \ |
| report_vm_status_error(__FILE__, __LINE__, "assert(" #p ") failed", \ |
| status, msg); \ |
| } \ |
| } while (0) |
| #endif // ASSERT |
| |
| // For backward compatibility. |
| #define assert_status(p, status, msg) vmassert_status(p, status, msg) |
| |
| // guarantee is like vmassert except it's always executed -- use it for |
| // cheap tests that catch errors that would otherwise be hard to find. |
| // guarantee is also used for Verify options. |
| // guarantee is not subject to DebuggingContext bypass. |
| #define guarantee(p, ...) \ |
| do { \ |
| if (!(p)) { \ |
| TOUCH_ASSERT_POISON; \ |
| report_vm_error(__FILE__, __LINE__, "guarantee(" #p ") failed", __VA_ARGS__); \ |
| } \ |
| } while (0) |
| |
| #define fatal(...) \ |
| do { \ |
| TOUCH_ASSERT_POISON; \ |
| report_fatal(INTERNAL_ERROR, __FILE__, __LINE__, __VA_ARGS__); \ |
| } while (0) |
| |
| // out of memory |
| #define vm_exit_out_of_memory(size, vm_err_type, ...) \ |
| do { \ |
| report_vm_out_of_memory(__FILE__, __LINE__, size, vm_err_type, __VA_ARGS__); \ |
| } while (0) |
| |
| #define ShouldNotCallThis() \ |
| do { \ |
| TOUCH_ASSERT_POISON; \ |
| report_should_not_call(__FILE__, __LINE__); \ |
| } while (0) |
| |
| #define ShouldNotReachHere() \ |
| do { \ |
| TOUCH_ASSERT_POISON; \ |
| report_should_not_reach_here(__FILE__, __LINE__); \ |
| } while (0) |
| |
| #define Unimplemented() \ |
| do { \ |
| TOUCH_ASSERT_POISON; \ |
| report_unimplemented(__FILE__, __LINE__); \ |
| } while (0) |
| |
| #define Untested(msg) \ |
| do { \ |
| report_untested(__FILE__, __LINE__, msg); \ |
| BREAKPOINT; \ |
| } while (0); |
| |
| |
| // types of VM error - originally in vmError.hpp |
| enum VMErrorType { |
| INTERNAL_ERROR = 0xe0000000, |
| OOM_MALLOC_ERROR = 0xe0000001, |
| OOM_MMAP_ERROR = 0xe0000002, |
| OOM_MPROTECT_ERROR = 0xe0000003, |
| OOM_JAVA_HEAP_FATAL = 0xe0000004 |
| }; |
| |
| // error reporting helper functions |
| ATTRIBUTE_NORETURN |
| void report_vm_error(const char* file, int line, const char* error_msg); |
| |
| ATTRIBUTE_NORETURN |
| ATTRIBUTE_PRINTF(4, 5) |
| void report_vm_error(const char* file, int line, const char* error_msg, |
| const char* detail_fmt, ...); |
| |
| ATTRIBUTE_NORETURN |
| void report_vm_status_error(const char* file, int line, const char* error_msg, |
| int status, const char* detail); |
| |
| ATTRIBUTE_NORETURN |
| ATTRIBUTE_PRINTF(4, 5) |
| void report_fatal(VMErrorType error_type, const char* file, int line, const char* detail_fmt, ...); |
| |
| ATTRIBUTE_NORETURN |
| ATTRIBUTE_PRINTF(5, 6) |
| void report_vm_out_of_memory(const char* file, int line, size_t size, VMErrorType vm_err_type, |
| const char* detail_fmt, ...); |
| |
| ATTRIBUTE_NORETURN void report_should_not_call(const char* file, int line); |
| ATTRIBUTE_NORETURN void report_should_not_reach_here(const char* file, int line); |
| ATTRIBUTE_NORETURN void report_unimplemented(const char* file, int line); |
| |
| // NOT ATTRIBUTE_NORETURN |
| void report_untested(const char* file, int line, const char* message); |
| |
| ATTRIBUTE_PRINTF(1, 2) |
| void warning(const char* format, ...); |
| |
| #define STATIC_ASSERT(Cond) static_assert((Cond), #Cond) |
| |
| // out of memory reporting |
| void report_java_out_of_memory(const char* message); |
| |
| // Returns true iff the address p is readable and *(intptr_t*)p != errvalue |
| extern "C" bool dbg_is_safe(const void* p, intptr_t errvalue); |
| extern "C" bool dbg_is_good_oop(oopDesc* o); |
| |
| #endif // SHARE_UTILITIES_DEBUG_HPP |
