llvm-project

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// -*- C++ -*-
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//===----------------------------------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#ifndef _LIBCPP___ASSERT
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#define _LIBCPP___ASSERT
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#include <__assertion_handler> // Note: this include is generated by CMake and is potentially vendor-provided.
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#include <__config>
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#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
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#  pragma GCC system_header
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#endif
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#define _LIBCPP_ASSERT(expression, message)                                                                            \
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  (__builtin_expect(static_cast<bool>(expression), 1)                                                                  \
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       ? (void)0                                                                                                       \
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       : _LIBCPP_ASSERTION_HANDLER(__FILE__ ":" _LIBCPP_TOSTRING(__LINE__) ": assertion " _LIBCPP_TOSTRING(            \
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             expression) " failed: " message "\n"))
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// TODO: __builtin_assume can currently inhibit optimizations. Until this has been fixed and we can add
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//       assumptions without a clear optimization intent, disable that to avoid worsening the code generation.
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//       See https://discourse.llvm.org/t/llvm-assume-blocks-optimization/71609 for a discussion.
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#if 0 && __has_builtin(__builtin_assume)
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#  define _LIBCPP_ASSUME(expression)                                                                                   \
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    (_LIBCPP_DIAGNOSTIC_PUSH _LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Wassume")                                              \
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         __builtin_assume(static_cast<bool>(expression)) _LIBCPP_DIAGNOSTIC_POP)
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#else
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#  define _LIBCPP_ASSUME(expression) ((void)0)
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#endif
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// clang-format off
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// Fast hardening mode checks.
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#if _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_FAST
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// Enabled checks.
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#  define _LIBCPP_ASSERT_VALID_INPUT_RANGE(expression, message)       _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(expression, message)    _LIBCPP_ASSERT(expression, message)
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// Disabled checks.
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// On most modern platforms, dereferencing a null pointer does not lead to an actual memory access.
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#  define _LIBCPP_ASSERT_NON_NULL(expression, message)                _LIBCPP_ASSUME(expression)
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// Overlapping ranges will make algorithms produce incorrect results but don't directly lead to a security
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// vulnerability.
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#  define _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(expression, message)  _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_VALID_DEALLOCATION(expression, message)      _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(expression, message) _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(expression, message)    _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(expression, message)  _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_PEDANTIC(expression, message)                _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(expression, message)    _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_INTERNAL(expression, message)                _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_UNCATEGORIZED(expression, message)           _LIBCPP_ASSUME(expression)
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// Extensive hardening mode checks.
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#elif _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_EXTENSIVE
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// Enabled checks.
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#  define _LIBCPP_ASSERT_VALID_INPUT_RANGE(expression, message)       _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(expression, message)    _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_NON_NULL(expression, message)                _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(expression, message)  _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_VALID_DEALLOCATION(expression, message)      _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(expression, message) _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(expression, message)    _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(expression, message)  _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_PEDANTIC(expression, message)                _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_UNCATEGORIZED(expression, message)           _LIBCPP_ASSERT(expression, message)
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// Disabled checks.
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#  define _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(expression, message)    _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_INTERNAL(expression, message)                _LIBCPP_ASSUME(expression)
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// Debug hardening mode checks.
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#elif _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_DEBUG
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// All checks enabled.
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#  define _LIBCPP_ASSERT_VALID_INPUT_RANGE(expression, message)       _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(expression, message)    _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_NON_NULL(expression, message)                _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(expression, message)  _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_VALID_DEALLOCATION(expression, message)      _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(expression, message) _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(expression, message)    _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(expression, message)  _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_PEDANTIC(expression, message)                _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(expression, message)    _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_INTERNAL(expression, message)                _LIBCPP_ASSERT(expression, message)
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#  define _LIBCPP_ASSERT_UNCATEGORIZED(expression, message)           _LIBCPP_ASSERT(expression, message)
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// Disable all checks if hardening is not enabled.
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#else
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// All checks disabled.
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#  define _LIBCPP_ASSERT_VALID_INPUT_RANGE(expression, message)       _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_VALID_ELEMENT_ACCESS(expression, message)    _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_NON_NULL(expression, message)                _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_NON_OVERLAPPING_RANGES(expression, message)  _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_VALID_DEALLOCATION(expression, message)      _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_VALID_EXTERNAL_API_CALL(expression, message) _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_COMPATIBLE_ALLOCATOR(expression, message)    _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_ARGUMENT_WITHIN_DOMAIN(expression, message)  _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_PEDANTIC(expression, message)                _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_SEMANTIC_REQUIREMENT(expression, message)    _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_INTERNAL(expression, message)                _LIBCPP_ASSUME(expression)
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#  define _LIBCPP_ASSERT_UNCATEGORIZED(expression, message)           _LIBCPP_ASSUME(expression)
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#endif // _LIBCPP_HARDENING_MODE == _LIBCPP_HARDENING_MODE_FAST
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// clang-format on
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#endif // _LIBCPP___ASSERT
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