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 //===----------------------------------------------------------------------===//
17 #include "llvm/Module.h"
18 #include "llvm/ModuleProvider.h"
19 #include "llvm/ADT/Triple.h"
20 #include "llvm/Support/CommandLine.h"
21 #include "llvm/Support/raw_ostream.h"
22 #include "llvm/System/Host.h"
23 #include "llvm/Target/SubtargetFeature.h"
24 #include "llvm/Target/TargetMachine.h"
25 #include "llvm/Target/TargetRegistry.h"
28 static cl::opt<std::string>
29 MArch("march", cl::desc("Architecture to generate assembly for (see --version)"));
31 static cl::opt<std::string>
33 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
34 cl::value_desc("cpu-name"),
37 static cl::list<std::string>
40 cl::desc("Target specific attributes (-mattr=help for details)"),
41 cl::value_desc("a1,+a2,-a3,..."));
43 /// selectTarget - Pick a target either via -march or by guessing the native
44 /// arch. Add any CPU features specified via -mcpu or -mattr.
45 TargetMachine *JIT::selectTarget(ModuleProvider *MP, std::string *ErrorStr) {
46 Triple TheTriple(sys::getHostTriple());
48 // Adjust the triple to match what the user requested.
50 TheTriple.setArch(Triple::getArchTypeForLLVMName(MArch));
53 const Target *TheTarget =
54 TargetRegistry::lookupTarget(TheTriple.getTriple(),
55 /*FallbackToHost=*/false,
64 if (!TheTarget->hasJIT()) {
65 errs() << "WARNING: This target JIT is not designed for the host you are"
66 << " running. If bad things happen, please choose a different "
67 << "-march switch.\n";
70 // Package up features to be passed to target/subtarget
71 std::string FeaturesStr;
72 if (!MCPU.empty() || !MAttrs.empty()) {
73 SubtargetFeatures Features;
74 Features.setCPU(MCPU);
75 for (unsigned i = 0; i != MAttrs.size(); ++i)
76 Features.AddFeature(MAttrs[i]);
77 FeaturesStr = Features.getString();
80 // Allocate a target...
81 TargetMachine *Target =
82 TheTarget->createTargetMachine(*MP->getModule(), TheTriple.getTriple(),
84 assert(Target && "Could not allocate target machine!");