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Diffstat (limited to 'include/my_compiler.h')
| -rw-r--r-- | include/my_compiler.h | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/include/my_compiler.h b/include/my_compiler.h new file mode 100644 index 00000000..b979b5a5 --- /dev/null +++ b/include/my_compiler.h @@ -0,0 +1,181 @@ +#ifndef MY_COMPILER_INCLUDED +#define MY_COMPILER_INCLUDED + +/* Copyright (c) 2010, 2011, Oracle and/or its affiliates. All rights reserved. + Copyright (c) 2017, 2022, MariaDB Corporation. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + This program 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 for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */ + +/** + Header for compiler-dependent features. + + Intended to contain a set of reusable wrappers for preprocessor + macros, attributes, pragmas, and any other features that are + specific to a target compiler. +*/ + +/** + Compiler-dependent internal convenience macros. +*/ + +/* C vs C++ */ +#ifdef __cplusplus +#define CONSTEXPR constexpr +#else +#define CONSTEXPR +#endif /* __cplusplus */ + + +/* GNU C/C++ */ +#if defined __GNUC__ +# define MY_ALIGN_EXT + +/* + __builtin_unreachable() removes the "statement may fall through" warning-as- + error when MY_ASSERT_UNREACHABLE() is used in "case xxx:" in switch (...) + statements. + abort() is there to prevent the execution from reaching the + __builtin_unreachable() as this may cause misleading stack traces. +*/ +# define MY_ASSERT_UNREACHABLE() { abort(); __builtin_unreachable(); } + +/* Microsoft Visual C++ */ +#elif defined _MSC_VER +# define MY_ALIGNOF(type) __alignof(type) +# define MY_ALIGNED(n) __declspec(align(n)) + +/* Oracle Solaris Studio */ +#elif defined(__SUNPRO_C) || defined(__SUNPRO_CC) +# if __SUNPRO_C >= 0x590 +# define MY_ALIGN_EXT +# endif + +/* IBM XL C/C++ */ +#elif defined __xlC__ +# if __xlC__ >= 0x0600 +# define MY_ALIGN_EXT +# endif + +/* HP aCC */ +#elif defined(__HP_aCC) || defined(__HP_cc) +# if (__HP_aCC >= 60000) || (__HP_cc >= 60000) +# define MY_ALIGN_EXT +# endif +#endif + +#ifdef MY_ALIGN_EXT +/** Specifies the minimum alignment of a type. */ +# define MY_ALIGNOF(type) __alignof__(type) +/** Determine the alignment requirement of a type. */ +# define MY_ALIGNED(n) __attribute__((__aligned__((n)))) +#endif + +/** + Generic (compiler-independent) features. +*/ + +#ifndef MY_ALIGNOF +# ifdef __cplusplus + template<typename type> struct my_alignof_helper { char m1; type m2; }; + /* Invalid for non-POD types, but most compilers give the right answer. */ +# define MY_ALIGNOF(type) offsetof(my_alignof_helper<type>, m2) +# else +# define MY_ALIGNOF(type) offsetof(struct { char m1; type m2; }, m2) +# endif +#endif + +#ifndef MY_ASSERT_UNREACHABLE +# define MY_ASSERT_UNREACHABLE() do { abort(); } while (0) +#endif + +/** + C++ Type Traits +*/ + +#ifdef __cplusplus + +/** + Opaque storage with a particular alignment. +*/ +# if defined(MY_ALIGNED) +/* Partial specialization used due to MSVC++. */ +template<size_t alignment> struct my_alignment_imp; +template<> struct MY_ALIGNED(1) my_alignment_imp<1> {}; +template<> struct MY_ALIGNED(2) my_alignment_imp<2> {}; +template<> struct MY_ALIGNED(4) my_alignment_imp<4> {}; +template<> struct MY_ALIGNED(8) my_alignment_imp<8> {}; +template<> struct MY_ALIGNED(16) my_alignment_imp<16> {}; +/* ... expand as necessary. */ +# else +template<size_t alignment> +struct my_alignment_imp { double m1; }; +# endif + +/** + A POD type with a given size and alignment. + + @remark If the compiler does not support a alignment attribute + (MY_ALIGN macro), the default alignment of a double is + used instead. + + @tparam size The minimum size. + @tparam alignment The desired alignment: 1, 2, 4, 8 or 16. +*/ +template <size_t size, size_t alignment> +struct my_aligned_storage +{ + union + { + char data[size]; + my_alignment_imp<alignment> align; + }; +}; + +#endif /* __cplusplus */ + +# ifndef MY_ALIGNED +/* + Make sure MY_ALIGNED can be used also on platforms where we don't + have a way of aligning data structures. +*/ +#define MY_ALIGNED(size) +#endif + +#ifdef __GNUC__ +# define ATTRIBUTE_NORETURN __attribute__((noreturn)) +# define ATTRIBUTE_NOINLINE __attribute__((noinline)) +/** Starting with GCC 4.3, the "cold" attribute is used to inform the +compiler that a function is unlikely executed. The function is +optimized for size rather than speed and on many targets it is placed +into special subsection of the text section so all cold functions +appears close together improving code locality of non-cold parts of +program. The paths leading to call of cold functions within code are +marked as unlikely by the branch prediction mechanism. optimize a +rarely invoked function for size instead for speed. */ +# define ATTRIBUTE_COLD __attribute__((cold)) +#elif defined _MSC_VER +# define ATTRIBUTE_NORETURN __declspec(noreturn) +# define ATTRIBUTE_NOINLINE __declspec(noinline) +#else +# define ATTRIBUTE_NORETURN /* empty */ +# define ATTRIBUTE_NOINLINE /* empty */ +#endif + +#ifndef ATTRIBUTE_COLD +# define ATTRIBUTE_COLD /* empty */ +#endif + +#include <my_attribute.h> + +#endif /* MY_COMPILER_INCLUDED */ |