1 //===- llvm/Support/Host.h - Host machine characteristics --------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // Methods for querying the nature of the host machine. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_SUPPORT_HOST_H 14 #define LLVM_SUPPORT_HOST_H 15 16 #include "llvm/ADT/StringMap.h" 17 18 #if defined(__linux__) || defined(__GNU__) || defined(__HAIKU__) 19 #include <endian.h> 20 #elif defined(_AIX) 21 #include <sys/machine.h> 22 #elif defined(__sun) 23 /* Solaris provides _BIG_ENDIAN/_LITTLE_ENDIAN selector in sys/types.h */ 24 #include <sys/types.h> 25 #define BIG_ENDIAN 4321 26 #define LITTLE_ENDIAN 1234 27 #if defined(_BIG_ENDIAN) 28 #define BYTE_ORDER BIG_ENDIAN 29 #else 30 #define BYTE_ORDER LITTLE_ENDIAN 31 #endif 32 #else 33 #if !defined(BYTE_ORDER) && !defined(_WIN32) 34 #include <machine/endian.h> 35 #endif 36 #endif 37 38 #include <string> 39 40 namespace llvm { 41 namespace sys { 42 43 #if defined(BYTE_ORDER) && defined(BIG_ENDIAN) && BYTE_ORDER == BIG_ENDIAN 44 constexpr bool IsBigEndianHost = true; 45 #else 46 constexpr bool IsBigEndianHost = false; 47 #endif 48 49 static const bool IsLittleEndianHost = !IsBigEndianHost; 50 51 /// getDefaultTargetTriple() - Return the default target triple the compiler 52 /// has been configured to produce code for. 53 /// 54 /// The target triple is a string in the format of: 55 /// CPU_TYPE-VENDOR-OPERATING_SYSTEM 56 /// or 57 /// CPU_TYPE-VENDOR-KERNEL-OPERATING_SYSTEM 58 std::string getDefaultTargetTriple(); 59 60 /// getProcessTriple() - Return an appropriate target triple for generating 61 /// code to be loaded into the current process, e.g. when using the JIT. 62 std::string getProcessTriple(); 63 64 /// getHostCPUName - Get the LLVM name for the host CPU. The particular format 65 /// of the name is target dependent, and suitable for passing as -mcpu to the 66 /// target which matches the host. 67 /// 68 /// \return - The host CPU name, or empty if the CPU could not be determined. 69 StringRef getHostCPUName(); 70 71 /// getHostCPUFeatures - Get the LLVM names for the host CPU features. 72 /// The particular format of the names are target dependent, and suitable for 73 /// passing as -mattr to the target which matches the host. 74 /// 75 /// \param Features - A string mapping feature names to either 76 /// true (if enabled) or false (if disabled). This routine makes no guarantees 77 /// about exactly which features may appear in this map, except that they are 78 /// all valid LLVM feature names. 79 /// 80 /// \return - True on success. 81 bool getHostCPUFeatures(StringMap<bool> &Features); 82 83 /// Get the number of physical cores (as opposed to logical cores returned 84 /// from thread::hardware_concurrency(), which includes hyperthreads). 85 /// Returns -1 if unknown for the current host system. 86 int getHostNumPhysicalCores(); 87 88 namespace detail { 89 /// Helper functions to extract HostCPUName from /proc/cpuinfo on linux. 90 StringRef getHostCPUNameForPowerPC(StringRef ProcCpuinfoContent); 91 StringRef getHostCPUNameForARM(StringRef ProcCpuinfoContent); 92 StringRef getHostCPUNameForS390x(StringRef ProcCpuinfoContent); 93 StringRef getHostCPUNameForBPF(); 94 } 95 } 96 } 97 98 #endif 99