1 //===-- TargetSelect.cpp - Target Chooser Code ----------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This just asks the TargetRegistry for the appropriate JIT to use, and allows
11 // the user to specify a specific one on the commandline with -march=x. Clients
12 // should initialize targets prior to calling createJIT.
14 //===----------------------------------------------------------------------===//
16 #include "llvm/ExecutionEngine/ExecutionEngine.h"
17 #include "llvm/Module.h"
18 #include "llvm/ADT/Triple.h"
19 #include "llvm/MC/SubtargetFeature.h"
20 #include "llvm/Target/TargetMachine.h"
21 #include "llvm/Support/CommandLine.h"
22 #include "llvm/Support/Host.h"
23 #include "llvm/Support/TargetRegistry.h"
24 #include "llvm/Support/raw_ostream.h"
27 /// selectTarget - Pick a target either via -march or by guessing the native
28 /// arch. Add any CPU features specified via -mcpu or -mattr.
29 TargetMachine *EngineBuilder::selectTarget(Module *Mod,
32 const SmallVectorImpl<std::string>& MAttrs,
35 std::string *ErrorStr) {
36 Triple TheTriple(Mod->getTargetTriple());
37 if (TheTriple.getTriple().empty())
38 TheTriple.setTriple(sys::getHostTriple());
40 // Adjust the triple to match what the user requested.
41 const Target *TheTarget = 0;
43 for (TargetRegistry::iterator it = TargetRegistry::begin(),
44 ie = TargetRegistry::end(); it != ie; ++it) {
45 if (MArch == it->getName()) {
52 *ErrorStr = "No available targets are compatible with this -march, "
53 "see -version for the available targets.\n";
57 // Adjust the triple to match (if known), otherwise stick with the
58 // module/host triple.
59 Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch);
60 if (Type != Triple::UnknownArch)
61 TheTriple.setArch(Type);
64 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Error);
72 if (!TheTarget->hasJIT()) {
73 errs() << "WARNING: This target JIT is not designed for the host you are"
74 << " running. If bad things happen, please choose a different "
75 << "-march switch.\n";
78 // Package up features to be passed to target/subtarget
79 std::string FeaturesStr;
80 if (!MAttrs.empty()) {
81 SubtargetFeatures Features;
82 for (unsigned i = 0; i != MAttrs.size(); ++i)
83 Features.AddFeature(MAttrs[i]);
84 FeaturesStr = Features.getString();
87 // Allocate a target...
88 TargetMachine *Target = TheTarget->createTargetMachine(TheTriple.getTriple(),
91 assert(Target && "Could not allocate target machine!");