Host.h revision 360784 
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#include <string>
19
20namespace llvm {
21namespace sys {
22
23  /// getDefaultTargetTriple() - Return the default target triple the compiler
24  /// has been configured to produce code for.
25  ///
26  /// The target triple is a string in the format of:
27  ///   CPU_TYPE-VENDOR-OPERATING_SYSTEM
28  /// or
29  ///   CPU_TYPE-VENDOR-KERNEL-OPERATING_SYSTEM
30  std::string getDefaultTargetTriple();
31
32  /// getProcessTriple() - Return an appropriate target triple for generating
33  /// code to be loaded into the current process, e.g. when using the JIT.
34  std::string getProcessTriple();
35
36  /// getHostCPUName - Get the LLVM name for the host CPU. The particular format
37  /// of the name is target dependent, and suitable for passing as -mcpu to the
38  /// target which matches the host.
39  ///
40  /// \return - The host CPU name, or empty if the CPU could not be determined.
41  StringRef getHostCPUName();
42
43  /// getHostCPUFeatures - Get the LLVM names for the host CPU features.
44  /// The particular format of the names are target dependent, and suitable for
45  /// passing as -mattr to the target which matches the host.
46  ///
47  /// \param Features - A string mapping feature names to either
48  /// true (if enabled) or false (if disabled). This routine makes no guarantees
49  /// about exactly which features may appear in this map, except that they are
50  /// all valid LLVM feature names.
51  ///
52  /// \return - True on success.
53  bool getHostCPUFeatures(StringMap<bool> &Features);
54
55  /// Get the number of physical cores (as opposed to logical cores returned
56  /// from thread::hardware_concurrency(), which includes hyperthreads).
57  /// Returns -1 if unknown for the current host system.
58  int getHostNumPhysicalCores();
59
60  namespace detail {
61  /// Helper functions to extract HostCPUName from /proc/cpuinfo on linux.
62  StringRef getHostCPUNameForPowerPC(StringRef ProcCpuinfoContent);
63  StringRef getHostCPUNameForARM(StringRef ProcCpuinfoContent);
64  StringRef getHostCPUNameForS390x(StringRef ProcCpuinfoContent);
65  StringRef getHostCPUNameForBPF();
66  }
67}
68}
69
70#endif
71