1 //===- llvm/Support/Host.h - Host machine characteristics --------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // Methods for querying the nature of the host machine. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_SUPPORT_HOST_H 15 #define LLVM_SUPPORT_HOST_H 16 17 #include "llvm/ADT/StringMap.h" 18 19 #if defined(__linux__) || defined(__GNU__) || defined(__HAIKU__) 20 #include <endian.h> 21 #elif defined(_AIX) 22 #include <sys/machine.h> 23 #elif defined(__sun) 24 /* Solaris provides _BIG_ENDIAN/_LITTLE_ENDIAN selector in sys/types.h */ 25 #include <sys/types.h> 26 #define BIG_ENDIAN 4321 27 #define LITTLE_ENDIAN 1234 28 #if defined(_BIG_ENDIAN) 29 #define BYTE_ORDER BIG_ENDIAN 30 #else 31 #define BYTE_ORDER LITTLE_ENDIAN 32 #endif 33 #else 34 #if !defined(BYTE_ORDER) && !defined(_WIN32) 35 #include <machine/endian.h> 36 #endif 37 #endif 38 39 #include <string> 40 41 namespace llvm { 42 namespace sys { 43 44 #if defined(BYTE_ORDER) && defined(BIG_ENDIAN) && BYTE_ORDER == BIG_ENDIAN 45 constexpr bool IsBigEndianHost = true; 46 #else 47 constexpr bool IsBigEndianHost = false; 48 #endif 49 50 static const bool IsLittleEndianHost = !IsBigEndianHost; 51 52 /// getDefaultTargetTriple() - Return the default target triple the compiler 53 /// has been configured to produce code for. 54 /// 55 /// The target triple is a string in the format of: 56 /// CPU_TYPE-VENDOR-OPERATING_SYSTEM 57 /// or 58 /// CPU_TYPE-VENDOR-KERNEL-OPERATING_SYSTEM 59 std::string getDefaultTargetTriple(); 60 61 /// getProcessTriple() - Return an appropriate target triple for generating 62 /// code to be loaded into the current process, e.g. when using the JIT. 63 std::string getProcessTriple(); 64 65 /// getHostCPUName - Get the LLVM name for the host CPU. The particular format 66 /// of the name is target dependent, and suitable for passing as -mcpu to the 67 /// target which matches the host. 68 /// 69 /// \return - The host CPU name, or empty if the CPU could not be determined. 70 StringRef getHostCPUName(); 71 72 /// getHostCPUFeatures - Get the LLVM names for the host CPU features. 73 /// The particular format of the names are target dependent, and suitable for 74 /// passing as -mattr to the target which matches the host. 75 /// 76 /// \param Features - A string mapping feature names to either 77 /// true (if enabled) or false (if disabled). This routine makes no guarantees 78 /// about exactly which features may appear in this map, except that they are 79 /// all valid LLVM feature names. 80 /// 81 /// \return - True on success. 82 bool getHostCPUFeatures(StringMap<bool> &Features); 83 84 /// Get the number of physical cores (as opposed to logical cores returned 85 /// from thread::hardware_concurrency(), which includes hyperthreads). 86 /// Returns -1 if unknown for the current host system. 87 int getHostNumPhysicalCores(); 88 89 namespace detail { 90 /// Helper functions to extract HostCPUName from /proc/cpuinfo on linux. 91 StringRef getHostCPUNameForPowerPC(StringRef ProcCpuinfoContent); 92 StringRef getHostCPUNameForARM(StringRef ProcCpuinfoContent); 93 StringRef getHostCPUNameForS390x(StringRef ProcCpuinfoContent); 94 StringRef getHostCPUNameForBPF(); 95 } 96 } 97 } 98 99 #endif 100