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 #include "llvm/Support/MemoryBuffer.h" 19 20 #if defined(__linux__) || defined(__GNU__) || defined(__HAIKU__) 21 #include <endian.h> 22 #elif defined(_AIX) 23 #include <sys/machine.h> 24 #else 25 #if !defined(BYTE_ORDER) && !defined(LLVM_ON_WIN32) 26 #include <machine/endian.h> 27 #endif 28 #endif 29 30 #include <string> 31 32 namespace llvm { 33 namespace sys { 34 35 #if defined(BYTE_ORDER) && defined(BIG_ENDIAN) && BYTE_ORDER == BIG_ENDIAN 36 constexpr bool IsBigEndianHost = true; 37 #else 38 constexpr bool IsBigEndianHost = false; 39 #endif 40 41 static const bool IsLittleEndianHost = !IsBigEndianHost; 42 43 /// getDefaultTargetTriple() - Return the default target triple the compiler 44 /// has been configured to produce code for. 45 /// 46 /// The target triple is a string in the format of: 47 /// CPU_TYPE-VENDOR-OPERATING_SYSTEM 48 /// or 49 /// CPU_TYPE-VENDOR-KERNEL-OPERATING_SYSTEM 50 std::string getDefaultTargetTriple(); 51 52 /// getProcessTriple() - Return an appropriate target triple for generating 53 /// code to be loaded into the current process, e.g. when using the JIT. 54 std::string getProcessTriple(); 55 56 /// getHostCPUName - Get the LLVM name for the host CPU. The particular format 57 /// of the name is target dependent, and suitable for passing as -mcpu to the 58 /// target which matches the host. 59 /// 60 /// \return - The host CPU name, or empty if the CPU could not be determined. 61 StringRef getHostCPUName(); 62 63 /// getHostCPUFeatures - Get the LLVM names for the host CPU features. 64 /// The particular format of the names are target dependent, and suitable for 65 /// passing as -mattr to the target which matches the host. 66 /// 67 /// \param Features - A string mapping feature names to either 68 /// true (if enabled) or false (if disabled). This routine makes no guarantees 69 /// about exactly which features may appear in this map, except that they are 70 /// all valid LLVM feature names. 71 /// 72 /// \return - True on success. 73 bool getHostCPUFeatures(StringMap<bool> &Features); 74 75 /// Get the number of physical cores (as opposed to logical cores returned 76 /// from thread::hardware_concurrency(), which includes hyperthreads). 77 /// Returns -1 if unknown for the current host system. 78 int getHostNumPhysicalCores(); 79 80 namespace detail { 81 /// Helper functions to extract HostCPUName from /proc/cpuinfo on linux. 82 StringRef getHostCPUNameForPowerPC(const StringRef &ProcCpuinfoContent); 83 StringRef getHostCPUNameForARM(const StringRef &ProcCpuinfoContent); 84 StringRef getHostCPUNameForS390x(const StringRef &ProcCpuinfoContent); 85 } 86 } 87 } 88 89 #endif 90
