1 /* 2 * Copyright (c) Meta Platforms, Inc. and affiliates. 3 * All rights reserved. 4 * 5 * This source code is licensed under both the BSD-style license (found in the 6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found 7 * in the COPYING file in the root directory of this source tree). 8 * You may select, at your option, one of the above-listed licenses. 9 */ 10 11 #ifndef ZSTD_PORTABILITY_MACROS_H 12 #define ZSTD_PORTABILITY_MACROS_H 13 14 /** 15 * This header file contains macro definitions to support portability. 16 * This header is shared between C and ASM code, so it MUST only 17 * contain macro definitions. It MUST not contain any C code. 18 * 19 * This header ONLY defines macros to detect platforms/feature support. 20 * 21 */ 22 23 24 /* compat. with non-clang compilers */ 25 #ifndef __has_attribute 26 #define __has_attribute(x) 0 27 #endif 28 29 /* compat. with non-clang compilers */ 30 #ifndef __has_builtin 31 # define __has_builtin(x) 0 32 #endif 33 34 /* compat. with non-clang compilers */ 35 #ifndef __has_feature 36 # define __has_feature(x) 0 37 #endif 38 39 /* detects whether we are being compiled under msan */ 40 #ifndef ZSTD_MEMORY_SANITIZER 41 # if __has_feature(memory_sanitizer) 42 # define ZSTD_MEMORY_SANITIZER 1 43 # else 44 # define ZSTD_MEMORY_SANITIZER 0 45 # endif 46 #endif 47 48 /* detects whether we are being compiled under asan */ 49 #ifndef ZSTD_ADDRESS_SANITIZER 50 # if __has_feature(address_sanitizer) 51 # define ZSTD_ADDRESS_SANITIZER 1 52 # elif defined(__SANITIZE_ADDRESS__) 53 # define ZSTD_ADDRESS_SANITIZER 1 54 # else 55 # define ZSTD_ADDRESS_SANITIZER 0 56 # endif 57 #endif 58 59 /* detects whether we are being compiled under dfsan */ 60 #ifndef ZSTD_DATAFLOW_SANITIZER 61 # if __has_feature(dataflow_sanitizer) 62 # define ZSTD_DATAFLOW_SANITIZER 1 63 # else 64 # define ZSTD_DATAFLOW_SANITIZER 0 65 # endif 66 #endif 67 68 /* Mark the internal assembly functions as hidden */ 69 #ifdef __ELF__ 70 # define ZSTD_HIDE_ASM_FUNCTION(func) .hidden func 71 #elif defined(__APPLE__) 72 # define ZSTD_HIDE_ASM_FUNCTION(func) .private_extern func 73 #else 74 # define ZSTD_HIDE_ASM_FUNCTION(func) 75 #endif 76 77 /* Compile time determination of BMI2 support */ 78 #ifndef STATIC_BMI2 79 # if defined(__BMI2__) 80 # define STATIC_BMI2 1 81 # elif defined(_MSC_VER) && defined(__AVX2__) 82 # define STATIC_BMI2 1 /* MSVC does not have a BMI2 specific flag, but every CPU that supports AVX2 also supports BMI2 */ 83 # endif 84 #endif 85 86 #ifndef STATIC_BMI2 87 # define STATIC_BMI2 0 88 #endif 89 90 /* Enable runtime BMI2 dispatch based on the CPU. 91 * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default. 92 */ 93 #ifndef DYNAMIC_BMI2 94 # if ((defined(__clang__) && __has_attribute(__target__)) \ 95 || (defined(__GNUC__) \ 96 && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))) \ 97 && (defined(__i386__) || defined(__x86_64__) || defined(_M_IX86) || defined(_M_X64)) \ 98 && !defined(__BMI2__) 99 # define DYNAMIC_BMI2 1 100 # else 101 # define DYNAMIC_BMI2 0 102 # endif 103 #endif 104 105 /** 106 * Only enable assembly for GNU C compatible compilers, 107 * because other platforms may not support GAS assembly syntax. 108 * 109 * Only enable assembly for Linux / MacOS / Win32, other platforms may 110 * work, but they haven't been tested. This could likely be 111 * extended to BSD systems. 112 * 113 * Disable assembly when MSAN is enabled, because MSAN requires 114 * 100% of code to be instrumented to work. 115 */ 116 #if defined(__GNUC__) 117 # if defined(__linux__) || defined(__linux) || defined(__APPLE__) || defined(_WIN32) 118 # if ZSTD_MEMORY_SANITIZER 119 # define ZSTD_ASM_SUPPORTED 0 120 # elif ZSTD_DATAFLOW_SANITIZER 121 # define ZSTD_ASM_SUPPORTED 0 122 # else 123 # define ZSTD_ASM_SUPPORTED 1 124 # endif 125 # else 126 # define ZSTD_ASM_SUPPORTED 0 127 # endif 128 #else 129 # define ZSTD_ASM_SUPPORTED 0 130 #endif 131 132 /** 133 * Determines whether we should enable assembly for x86-64 134 * with BMI2. 135 * 136 * Enable if all of the following conditions hold: 137 * - ASM hasn't been explicitly disabled by defining ZSTD_DISABLE_ASM 138 * - Assembly is supported 139 * - We are compiling for x86-64 and either: 140 * - DYNAMIC_BMI2 is enabled 141 * - BMI2 is supported at compile time 142 */ 143 #if !defined(ZSTD_DISABLE_ASM) && \ 144 ZSTD_ASM_SUPPORTED && \ 145 defined(__x86_64__) && \ 146 (DYNAMIC_BMI2 || defined(__BMI2__)) 147 # define ZSTD_ENABLE_ASM_X86_64_BMI2 1 148 #else 149 # define ZSTD_ENABLE_ASM_X86_64_BMI2 0 150 #endif 151 152 /* 153 * For x86 ELF targets, add .note.gnu.property section for Intel CET in 154 * assembly sources when CET is enabled. 155 * 156 * Additionally, any function that may be called indirectly must begin 157 * with ZSTD_CET_ENDBRANCH. 158 */ 159 #if defined(__ELF__) && (defined(__x86_64__) || defined(__i386__)) \ 160 && defined(__has_include) 161 # if __has_include(<cet.h>) 162 # include <cet.h> 163 # define ZSTD_CET_ENDBRANCH _CET_ENDBR 164 # endif 165 #endif 166 167 #ifndef ZSTD_CET_ENDBRANCH 168 # define ZSTD_CET_ENDBRANCH 169 #endif 170 171 #endif /* ZSTD_PORTABILITY_MACROS_H */ 172
Indexes created Fri Jun 12 00:25:51 UTC 2026