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Diffstat (limited to '')
| -rw-r--r-- | third_party/zstd/lib/common/portability_macros.h | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/third_party/zstd/lib/common/portability_macros.h b/third_party/zstd/lib/common/portability_macros.h new file mode 100644 index 0000000000..e50314a78e --- /dev/null +++ b/third_party/zstd/lib/common/portability_macros.h @@ -0,0 +1,158 @@ +/* + * Copyright (c) Meta Platforms, Inc. and affiliates. + * All rights reserved. + * + * This source code is licensed under both the BSD-style license (found in the + * LICENSE file in the root directory of this source tree) and the GPLv2 (found + * in the COPYING file in the root directory of this source tree). + * You may select, at your option, one of the above-listed licenses. + */ + +#ifndef ZSTD_PORTABILITY_MACROS_H +#define ZSTD_PORTABILITY_MACROS_H + +/** + * This header file contains macro definitions to support portability. + * This header is shared between C and ASM code, so it MUST only + * contain macro definitions. It MUST not contain any C code. + * + * This header ONLY defines macros to detect platforms/feature support. + * + */ + + +/* compat. with non-clang compilers */ +#ifndef __has_attribute + #define __has_attribute(x) 0 +#endif + +/* compat. with non-clang compilers */ +#ifndef __has_builtin +# define __has_builtin(x) 0 +#endif + +/* compat. with non-clang compilers */ +#ifndef __has_feature +# define __has_feature(x) 0 +#endif + +/* detects whether we are being compiled under msan */ +#ifndef ZSTD_MEMORY_SANITIZER +# if __has_feature(memory_sanitizer) +# define ZSTD_MEMORY_SANITIZER 1 +# else +# define ZSTD_MEMORY_SANITIZER 0 +# endif +#endif + +/* detects whether we are being compiled under asan */ +#ifndef ZSTD_ADDRESS_SANITIZER +# if __has_feature(address_sanitizer) +# define ZSTD_ADDRESS_SANITIZER 1 +# elif defined(__SANITIZE_ADDRESS__) +# define ZSTD_ADDRESS_SANITIZER 1 +# else +# define ZSTD_ADDRESS_SANITIZER 0 +# endif +#endif + +/* detects whether we are being compiled under dfsan */ +#ifndef ZSTD_DATAFLOW_SANITIZER +# if __has_feature(dataflow_sanitizer) +# define ZSTD_DATAFLOW_SANITIZER 1 +# else +# define ZSTD_DATAFLOW_SANITIZER 0 +# endif +#endif + +/* Mark the internal assembly functions as hidden */ +#ifdef __ELF__ +# define ZSTD_HIDE_ASM_FUNCTION(func) .hidden func +#elif defined(__APPLE__) +# define ZSTD_HIDE_ASM_FUNCTION(func) .private_extern func +#else +# define ZSTD_HIDE_ASM_FUNCTION(func) +#endif + +/* Enable runtime BMI2 dispatch based on the CPU. + * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default. + */ +#ifndef DYNAMIC_BMI2 + #if ((defined(__clang__) && __has_attribute(__target__)) \ + || (defined(__GNUC__) \ + && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))) \ + && (defined(__x86_64__) || defined(_M_X64)) \ + && !defined(__BMI2__) + # define DYNAMIC_BMI2 1 + #else + # define DYNAMIC_BMI2 0 + #endif +#endif + +/** + * Only enable assembly for GNUC compatible compilers, + * because other platforms may not support GAS assembly syntax. + * + * Only enable assembly for Linux / MacOS, other platforms may + * work, but they haven't been tested. This could likely be + * extended to BSD systems. + * + * Disable assembly when MSAN is enabled, because MSAN requires + * 100% of code to be instrumented to work. + */ +#if defined(__GNUC__) +# if defined(__linux__) || defined(__linux) || defined(__APPLE__) +# if ZSTD_MEMORY_SANITIZER +# define ZSTD_ASM_SUPPORTED 0 +# elif ZSTD_DATAFLOW_SANITIZER +# define ZSTD_ASM_SUPPORTED 0 +# else +# define ZSTD_ASM_SUPPORTED 1 +# endif +# else +# define ZSTD_ASM_SUPPORTED 0 +# endif +#else +# define ZSTD_ASM_SUPPORTED 0 +#endif + +/** + * Determines whether we should enable assembly for x86-64 + * with BMI2. + * + * Enable if all of the following conditions hold: + * - ASM hasn't been explicitly disabled by defining ZSTD_DISABLE_ASM + * - Assembly is supported + * - We are compiling for x86-64 and either: + * - DYNAMIC_BMI2 is enabled + * - BMI2 is supported at compile time + */ +#if !defined(ZSTD_DISABLE_ASM) && \ + ZSTD_ASM_SUPPORTED && \ + defined(__x86_64__) && \ + (DYNAMIC_BMI2 || defined(__BMI2__)) +# define ZSTD_ENABLE_ASM_X86_64_BMI2 1 +#else +# define ZSTD_ENABLE_ASM_X86_64_BMI2 0 +#endif + +/* + * For x86 ELF targets, add .note.gnu.property section for Intel CET in + * assembly sources when CET is enabled. + * + * Additionally, any function that may be called indirectly must begin + * with ZSTD_CET_ENDBRANCH. + */ +#if defined(__ELF__) && (defined(__x86_64__) || defined(__i386__)) \ + && defined(__has_include) +# if __has_include(<cet.h>) +# include <cet.h> +# define ZSTD_CET_ENDBRANCH _CET_ENDBR +# endif +#endif + +#ifndef ZSTD_CET_ENDBRANCH +# define ZSTD_CET_ENDBRANCH +#endif + +#endif /* ZSTD_PORTABILITY_MACROS_H */ |