1 /* 2 * Copyright (c) Facebook, Inc. 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 defintions 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 69 /* Enable runtime BMI2 dispatch based on the CPU. 70 * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default. 71 */ 72 #ifndef DYNAMIC_BMI2 73 #if ((defined(__clang__) && __has_attribute(__target__)) \ 74 || (defined(__GNUC__) \ 75 && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))) \ 76 && (defined(__x86_64__) || defined(_M_X64)) \ 77 && !defined(__BMI2__) 78 # define DYNAMIC_BMI2 1 79 #else 80 # define DYNAMIC_BMI2 0 81 #endif 82 #endif 83 84 /** 85 * Only enable assembly for GNUC comptabile compilers, 86 * because other platforms may not support GAS assembly syntax. 87 * 88 * Only enable assembly for Linux / MacOS, other platforms may 89 * work, but they haven't been tested. This could likely be 90 * extended to BSD systems. 91 * 92 * Disable assembly when MSAN is enabled, because MSAN requires 93 * 100% of code to be instrumented to work. 94 */ 95 #if defined(__GNUC__) 96 # if defined(__linux__) || defined(__linux) || defined(__APPLE__) 97 # if ZSTD_MEMORY_SANITIZER 98 # define ZSTD_ASM_SUPPORTED 0 99 # elif ZSTD_DATAFLOW_SANITIZER 100 # define ZSTD_ASM_SUPPORTED 0 101 # else 102 # define ZSTD_ASM_SUPPORTED 1 103 # endif 104 # else 105 # define ZSTD_ASM_SUPPORTED 0 106 # endif 107 #else 108 # define ZSTD_ASM_SUPPORTED 0 109 #endif 110 111 /** 112 * Determines whether we should enable assembly for x86-64 113 * with BMI2. 114 * 115 * Enable if all of the following conditions hold: 116 * - ASM hasn't been explicitly disabled by defining ZSTD_DISABLE_ASM 117 * - Assembly is supported 118 * - We are compiling for x86-64 and either: 119 * - DYNAMIC_BMI2 is enabled 120 * - BMI2 is supported at compile time 121 */ 122 #if !defined(ZSTD_DISABLE_ASM) && \ 123 ZSTD_ASM_SUPPORTED && \ 124 defined(__x86_64__) && \ 125 (DYNAMIC_BMI2 || defined(__BMI2__)) 126 # define ZSTD_ENABLE_ASM_X86_64_BMI2 1 127 #else 128 # define ZSTD_ENABLE_ASM_X86_64_BMI2 0 129 #endif 130 131 #endif /* ZSTD_PORTABILITY_MACROS_H */ 132