/* * 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 #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 */