1 //===--- TargetRegistry.cpp - Target registration -------------------------===//
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 #include "llvm/Support/TargetRegistry.h"
11 #include "llvm/ADT/STLExtras.h"
12 #include "llvm/ADT/StringRef.h"
13 #include "llvm/Support/Host.h"
14 #include "llvm/Support/raw_ostream.h"
15 #include <cassert>
16 #include <vector>
17 using namespace llvm;
18
19 // Clients are responsible for avoid race conditions in registration.
20 static Target *FirstTarget = nullptr;
21
begin()22 TargetRegistry::iterator TargetRegistry::begin() {
23 return iterator(FirstTarget);
24 }
25
lookupTarget(const std::string & ArchName,Triple & TheTriple,std::string & Error)26 const Target *TargetRegistry::lookupTarget(const std::string &ArchName,
27 Triple &TheTriple,
28 std::string &Error) {
29 // Allocate target machine. First, check whether the user has explicitly
30 // specified an architecture to compile for. If so we have to look it up by
31 // name, because it might be a backend that has no mapping to a target triple.
32 const Target *TheTarget = nullptr;
33 if (!ArchName.empty()) {
34 for (TargetRegistry::iterator it = TargetRegistry::begin(),
35 ie = TargetRegistry::end(); it != ie; ++it) {
36 if (ArchName == it->getName()) {
37 TheTarget = &*it;
38 break;
39 }
40 }
41
42 if (!TheTarget) {
43 Error = "error: invalid target '" + ArchName + "'.\n";
44 return nullptr;
45 }
46
47 // Adjust the triple to match (if known), otherwise stick with the
48 // given triple.
49 Triple::ArchType Type = Triple::getArchTypeForLLVMName(ArchName);
50 if (Type != Triple::UnknownArch)
51 TheTriple.setArch(Type);
52 } else {
53 // Get the target specific parser.
54 std::string TempError;
55 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), TempError);
56 if (!TheTarget) {
57 Error = ": error: unable to get target for '"
58 + TheTriple.getTriple()
59 + "', see --version and --triple.\n";
60 return nullptr;
61 }
62 }
63
64 return TheTarget;
65 }
66
lookupTarget(const std::string & TT,std::string & Error)67 const Target *TargetRegistry::lookupTarget(const std::string &TT,
68 std::string &Error) {
69 // Provide special warning when no targets are initialized.
70 if (begin() == end()) {
71 Error = "Unable to find target for this triple (no targets are registered)";
72 return nullptr;
73 }
74 const Target *Matching = nullptr;
75 Triple::ArchType Arch = Triple(TT).getArch();
76 for (iterator it = begin(), ie = end(); it != ie; ++it) {
77 if (it->ArchMatchFn(Arch)) {
78 if (Matching) {
79 Error = std::string("Cannot choose between targets \"") +
80 Matching->Name + "\" and \"" + it->Name + "\"";
81 return nullptr;
82 }
83 Matching = &*it;
84 }
85 }
86
87 if (!Matching) {
88 Error = "No available targets are compatible with this triple, "
89 "see -version for the available targets.";
90 return nullptr;
91 }
92
93 return Matching;
94 }
95
RegisterTarget(Target & T,const char * Name,const char * ShortDesc,Target::ArchMatchFnTy ArchMatchFn,bool HasJIT)96 void TargetRegistry::RegisterTarget(Target &T,
97 const char *Name,
98 const char *ShortDesc,
99 Target::ArchMatchFnTy ArchMatchFn,
100 bool HasJIT) {
101 assert(Name && ShortDesc && ArchMatchFn &&
102 "Missing required target information!");
103
104 // Check if this target has already been initialized, we allow this as a
105 // convenience to some clients.
106 if (T.Name)
107 return;
108
109 // Add to the list of targets.
110 T.Next = FirstTarget;
111 FirstTarget = &T;
112
113 T.Name = Name;
114 T.ShortDesc = ShortDesc;
115 T.ArchMatchFn = ArchMatchFn;
116 T.HasJIT = HasJIT;
117 }
118
TargetArraySortFn(const std::pair<StringRef,const Target * > * LHS,const std::pair<StringRef,const Target * > * RHS)119 static int TargetArraySortFn(const std::pair<StringRef, const Target *> *LHS,
120 const std::pair<StringRef, const Target *> *RHS) {
121 return LHS->first.compare(RHS->first);
122 }
123
printRegisteredTargetsForVersion()124 void TargetRegistry::printRegisteredTargetsForVersion() {
125 std::vector<std::pair<StringRef, const Target*> > Targets;
126 size_t Width = 0;
127 for (TargetRegistry::iterator I = TargetRegistry::begin(),
128 E = TargetRegistry::end();
129 I != E; ++I) {
130 Targets.push_back(std::make_pair(I->getName(), &*I));
131 Width = std::max(Width, Targets.back().first.size());
132 }
133 array_pod_sort(Targets.begin(), Targets.end(), TargetArraySortFn);
134
135 raw_ostream &OS = outs();
136 OS << " Registered Targets:\n";
137 for (unsigned i = 0, e = Targets.size(); i != e; ++i) {
138 OS << " " << Targets[i].first;
139 OS.indent(Width - Targets[i].first.size()) << " - "
140 << Targets[i].second->getShortDescription() << '\n';
141 }
142 if (Targets.empty())
143 OS << " (none)\n";
144 }
145