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,
33 const TargetOptions &Options,
37 std::string *ErrorStr) {
38 Triple TheTriple(Mod->getTargetTriple());
39 if (TheTriple.getTriple().empty())
40 TheTriple.setTriple(sys::getDefaultTargetTriple());
42 // Adjust the triple to match what the user requested.
43 const Target *TheTarget = 0;
45 for (TargetRegistry::iterator it = TargetRegistry::begin(),
46 ie = TargetRegistry::end(); it != ie; ++it) {
47 if (MArch == it->getName()) {
54 *ErrorStr = "No available targets are compatible with this -march, "
55 "see -version for the available targets.\n";
59 // Adjust the triple to match (if known), otherwise stick with the
60 // module/host triple.
61 Triple::ArchType Type = Triple::getArchTypeForLLVMName(MArch);
62 if (Type != Triple::UnknownArch)
63 TheTriple.setArch(Type);
66 TheTarget = TargetRegistry::lookupTarget(TheTriple.getTriple(), Error);
74 if (!TheTarget->hasJIT()) {
75 errs() << "WARNING: This target JIT is not designed for the host you are"
76 << " running. If bad things happen, please choose a different "
77 << "-march switch.\n";
80 // Package up features to be passed to target/subtarget
81 std::string FeaturesStr;
82 if (!MAttrs.empty()) {
83 SubtargetFeatures Features;
84 for (unsigned i = 0; i != MAttrs.size(); ++i)
85 Features.AddFeature(MAttrs[i]);
86 FeaturesStr = Features.getString();
89 // Allocate a target...
90 TargetMachine *Target = TheTarget->createTargetMachine(TheTriple.getTriple(),
94 assert(Target && "Could not allocate target machine!");