LLVM  9.0.0svn
Host.h
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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.
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.
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);
94  }
95 }
96 }
97 
98 #endif
This class represents lattice values for constants.
Definition: AllocatorList.h:23
StringRef getHostCPUNameForPowerPC(StringRef ProcCpuinfoContent)
Helper functions to extract HostCPUName from /proc/cpuinfo on linux.
Definition: Host.cpp:67
std::string getDefaultTargetTriple()
getDefaultTargetTriple() - Return the default target triple the compiler has been configured to produ...
StringRef getHostCPUNameForS390x(StringRef ProcCpuinfoContent)
Definition: Host.cpp:282
int getHostNumPhysicalCores()
Get the number of physical cores (as opposed to logical cores returned from thread::hardware_concurre...
Definition: Host.cpp:1282
constexpr bool IsBigEndianHost
Definition: Host.h:46
static const bool IsLittleEndianHost
Definition: Host.h:49
StringRef getHostCPUNameForBPF()
Definition: Host.cpp:335
std::string getProcessTriple()
getProcessTriple() - Return an appropriate target triple for generating code to be loaded into the cu...
Definition: Host.cpp:1504
StringRef getHostCPUName()
getHostCPUName - Get the LLVM name for the host CPU.
Definition: Host.cpp:1210
StringRef getHostCPUNameForARM(StringRef ProcCpuinfoContent)
Definition: Host.cpp:146
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
bool getHostCPUFeatures(StringMap< bool > &Features)
getHostCPUFeatures - Get the LLVM names for the host CPU features.
Definition: Host.cpp:1501