Host.inc revision 221345 
1 //===- llvm/Support/Unix/Host.inc -------------------------------*- 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// This file implements the UNIX Host support.
11//
12//===----------------------------------------------------------------------===//
13
14//===----------------------------------------------------------------------===//
15//=== WARNING: Implementation here must contain only generic UNIX code that
16//===          is guaranteed to work on *all* UNIX variants.
17//===----------------------------------------------------------------------===//
18
19#include "llvm/Config/config.h"
20#include "llvm/ADT/StringRef.h"
21#include "Unix.h"
22#include <sys/utsname.h>
23#include <cctype>
24#include <string>
25
26using namespace llvm;
27
28static std::string getOSVersion() {
29  struct utsname info;
30
31  if (uname(&info))
32    return "";
33
34  return info.release;
35}
36
37std::string sys::getHostTriple() {
38  // FIXME: Derive directly instead of relying on the autoconf generated
39  // variable.
40
41  StringRef HostTripleString(LLVM_HOSTTRIPLE);
42  std::pair<StringRef, StringRef> ArchSplit = HostTripleString.split('-');
43
44  // Normalize the arch, since the host triple may not actually match the host.
45  std::string Arch = ArchSplit.first;
46
47  // It would be nice to do this in terms of llvm::Triple, but that is in
48  // Support which is layered above us.
49#if defined(__x86_64__)
50  Arch = "x86_64";
51#elif defined(__i386__)
52  Arch = "i386";
53#elif defined(__ppc64__)
54  Arch = "powerpc64";
55#elif defined(__ppc__)
56  Arch = "powerpc";
57#elif defined(__arm__)
58
59  // FIXME: We need to pick the right ARM triple (which involves querying the
60  // chip). However, for now this is most important for LLVM arch selection, so
61  // we only need to make sure to distinguish ARM and Thumb.
62#  if defined(__thumb__)
63  Arch = "thumb";
64#  else
65  Arch = "arm";
66#  endif
67
68#else
69
70  // FIXME: When enough auto-detection is in place, this should just
71  // #error. Then at least the arch selection is done, and we only need the OS
72  // etc selection to kill off the use of LLVM_HOSTTRIPLE.
73
74#endif
75
76  std::string Triple(Arch);
77  Triple += '-';
78  Triple += ArchSplit.second;
79
80  // Force i<N>86 to i386.
81  if (Triple[0] == 'i' && isdigit(Triple[1]) &&
82      Triple[2] == '8' && Triple[3] == '6')
83    Triple[1] = '3';
84
85  // On darwin, we want to update the version to match that of the
86  // host.
87  std::string::size_type DarwinDashIdx = Triple.find("-darwin");
88  if (DarwinDashIdx != std::string::npos) {
89    Triple.resize(DarwinDashIdx + strlen("-darwin"));
90    Triple += getOSVersion();
91  }
92
93  return Triple;
94}
95