LLVM  8.0.1
Host.h
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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.
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.
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.
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);
95  }
96 }
97 }
98 
99 #endif
This class represents lattice values for constants.
Definition: AllocatorList.h:24
StringRef getHostCPUNameForPowerPC(StringRef ProcCpuinfoContent)
Helper functions to extract HostCPUName from /proc/cpuinfo on linux.
Definition: Host.cpp:68
std::string getDefaultTargetTriple()
getDefaultTargetTriple() - Return the default target triple the compiler has been configured to produ...
const FeatureBitset Features
StringRef getHostCPUNameForS390x(StringRef ProcCpuinfoContent)
Definition: Host.cpp:277
int getHostNumPhysicalCores()
Get the number of physical cores (as opposed to logical cores returned from thread::hardware_concurre...
Definition: Host.cpp:1215
constexpr bool IsBigEndianHost
Definition: Host.h:47
static const bool IsLittleEndianHost
Definition: Host.h:50
StringRef getHostCPUNameForBPF()
Definition: Host.cpp:330
std::string getProcessTriple()
getProcessTriple() - Return an appropriate target triple for generating code to be loaded into the cu...
Definition: Host.cpp:1430
StringRef getHostCPUName()
getHostCPUName - Get the LLVM name for the host CPU.
Definition: Host.cpp:1143
StringRef getHostCPUNameForARM(StringRef ProcCpuinfoContent)
Definition: Host.cpp:147
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:49
bool getHostCPUFeatures(StringMap< bool > &Features)
getHostCPUFeatures - Get the LLVM names for the host CPU features.
Definition: Host.cpp:1427