X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;ds=sidebyside;f=include%2Flttng%2Fust-compiler.h;h=b7fd2c1c42bff2bac5d6bfc1c4f403a61fa82234;hb=3615ef97a1075d302b5faad557154785135b7eb7;hp=1d04da1ac39857a6d35533794e7341fefb99ce4d;hpb=b3f60bbfff0d8b4ead55c0dc7f21985ffb70997e;p=lttng-ust.git diff --git a/include/lttng/ust-compiler.h b/include/lttng/ust-compiler.h index 1d04da1a..b7fd2c1c 100644 --- a/include/lttng/ust-compiler.h +++ b/include/lttng/ust-compiler.h @@ -1,30 +1,146 @@ +/* + * SPDX-License-Identifier: MIT + * + * Copyright (C) 2011-2012 Mathieu Desnoyers + * Copyright (C) 2011-2012 Paul Woegerer + */ + #ifndef _LTTNG_UST_COMPILER_H #define _LTTNG_UST_COMPILER_H +#include + +#define lttng_ust_notrace __attribute__((no_instrument_function)) + /* - * Copyright 2011-2012 - Mathieu Desnoyers - * Paul Woegerer + * Clang supports the no_sanitize variable attribute on global variables. + * GCC only supports the no_sanitize_address function attribute, which is + * not what we need. + */ +#if defined(__clang__) +# if __has_feature(address_sanitizer) +# define __lttng_ust_variable_attribute_no_sanitize_address \ + __attribute__((no_sanitize("address"))) +# else +# define __lttng_ust_variable_attribute_no_sanitize_address +# endif +#else +# define __lttng_ust_variable_attribute_no_sanitize_address +#endif + +/* + * g++ 4.8 and prior do not support C99 compound literals. Therefore, + * force allocating those on the heap with these C++ compilers. + */ +#if defined (__cplusplus) && !defined (__clang__) && defined (__GNUC__) && \ + ((__GNUC__ < 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ <= 8))) +# ifndef LTTNG_UST_ALLOCATE_COMPOUND_LITERAL_ON_HEAP +# define LTTNG_UST_ALLOCATE_COMPOUND_LITERAL_ON_HEAP +# endif +#endif + +/* + * Compound literals with static storage are needed by LTTng. + * Compound literals are part of the C99 and C11 standards, but not + * part of the C++ standards. However, those are supported by both g++ and + * clang. In order to be strictly C++11 compliant, defining + * LTTNG_UST_ALLOCATE_COMPOUND_LITERAL_ON_HEAP before including this header + * allocates those on the heap in C++. * - * Permission is hereby granted, free of charge, to any person obtaining a copy - * of this software and associated documentation files (the "Software"), to deal - * in the Software without restriction, including without limitation the rights - * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell - * copies of the Software, and to permit persons to whom the Software is - * furnished to do so, subject to the following conditions: + * Example use: + * static struct mystruct *var = LTTNG_UST_COMPOUND_LITERAL(struct mystruct, { 1, 2, 3 }); + */ +#if defined (__cplusplus) && defined (LTTNG_UST_ALLOCATE_COMPOUND_LITERAL_ON_HEAP) +#define LTTNG_UST_COMPOUND_LITERAL(type, ...) new (type) __VA_ARGS__ +#else +#define LTTNG_UST_COMPOUND_LITERAL(type, ...) (type[]) { __VA_ARGS__ } +#endif + +/* + * Compile time assertion. + * - predicate: boolean expression to evaluate, + * - msg: string to print to the user on failure when `static_assert()` is + * supported, + * - c_identifier_msg: message to be included in the typedef to emulate a + * static assertion. This parameter must be a valid C identifier as it will + * be used as a typedef name. + */ +#ifdef __cplusplus +#define lttng_ust_static_assert(predicate, msg, c_identifier_msg) \ + static_assert(predicate, msg) +#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L) +#define lttng_ust_static_assert(predicate, msg, c_identifier_msg) \ + _Static_assert(predicate, msg) +#else +/* + * Evaluates the predicate and emit a compilation error on failure. * - * The above copyright notice and this permission notice shall be included in - * all copies or substantial portions of the Software. + * If the predicate evaluates to true, this macro emits a typedef of an array + * of size 0. * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE - * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, - * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE - * SOFTWARE. + * If the predicate evaluates to false, this macro emits a typedef of an array + * of negative size which is invalid in C and forces a compiler error. The msg + * parameter is used in the tentative typedef so it is printed to the user. */ +#define lttng_ust_static_assert(predicate, msg, c_identifier_msg) \ + typedef char lttng_ust_static_assert_##c_identifier_msg[2*!!(predicate)-1] +#endif -#define lttng_ust_notrace __attribute__((no_instrument_function)) -#define LTTNG_PACKED __attribute__((__packed__)) +/* Combine two tokens. */ +#define LTTNG_UST_COMPILER__COMBINE_TOKENS(_tokena, _tokenb) \ + _tokena##_tokenb +#define LTTNG_UST_COMPILER_COMBINE_TOKENS(_tokena, _tokenb) \ + LTTNG_UST_COMPILER__COMBINE_TOKENS(_tokena, _tokenb) +/* + * Wrap constructor and destructor functions to invoke them as functions with + * the constructor/destructor GNU C attributes when building as C, or as the + * constructor/destructor of a variable defined within an anonymous namespace + * when building as C++. + */ +#ifdef __cplusplus +#define LTTNG_UST_DECLARE_CONSTRUCTOR_DESTRUCTOR(name, constructor_func, \ + destructor_func, ...) \ +namespace lttng { \ +namespace ust { \ +namespace details { \ +class LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_constructor_destructor_, \ + name) { \ +public: \ + LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_constructor_destructor_, name)() __VA_ARGS__; \ + ~LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_constructor_destructor_, name)() __VA_ARGS__; \ +}; \ +LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_constructor_destructor_, name)::LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_constructor_destructor_, name)() \ +{ \ + constructor_func(); \ +} \ +LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_constructor_destructor_, name)::~LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_constructor_destructor_, name)() \ +{ \ + destructor_func(); \ +} \ +} \ +} \ +} \ + \ +namespace { \ +const lttng::ust::details::LTTNG_UST_COMPILER_COMBINE_TOKENS( \ + lttng_ust_constructor_destructor_, name) \ + LTTNG_UST_COMPILER_COMBINE_TOKENS(name, registration_instance); \ +} +#else /* __cplusplus */ +#define LTTNG_UST_DECLARE_CONSTRUCTOR_DESTRUCTOR(name, constructor_func, \ + destructor_func, ...) \ + static void LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_constructor_, name)(void) \ + __attribute__((constructor)) __VA_ARGS__; \ + static void LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_constructor_, name)(void) \ + { \ + constructor_func(); \ + } \ + static void LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_destructor_, name)(void) \ + __attribute__((destructor)) __VA_ARGS__; \ + static void LTTNG_UST_COMPILER_COMBINE_TOKENS(lttng_ust_destructor_, name)(void) \ + { \ + destructor_func(); \ + } +#endif #endif /* _LTTNG_UST_COMPILER_H */