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 TargetMachineRegistry for the appropriate JIT to use, and
11 // allows the user to specify a specific one on the commandline with -march=x.
13 //===----------------------------------------------------------------------===//
16 #include "llvm/Module.h"
17 #include "llvm/ModuleProvider.h"
18 #include "llvm/Support/RegistryParser.h"
19 #include "llvm/Support/Streams.h"
20 #include "llvm/Target/SubtargetFeature.h"
21 #include "llvm/Target/TargetMachine.h"
22 #include "llvm/Target/TargetMachineRegistry.h"
25 static cl::opt<const TargetMachineRegistry::entry*, false,
26 RegistryParser<TargetMachine> >
27 MArch("march", cl::desc("Architecture to generate assembly for:"));
29 static cl::opt<std::string>
31 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
32 cl::value_desc("cpu-name"),
35 static cl::list<std::string>
38 cl::desc("Target specific attributes (-mattr=help for details)"),
39 cl::value_desc("a1,+a2,-a3,..."));
41 /// createInternal - Create an return a new JIT compiler if there is one
42 /// available for the current target. Otherwise, return null.
44 ExecutionEngine *JIT::createJIT(ModuleProvider *MP, std::string *ErrorStr,
45 JITMemoryManager *JMM,
46 CodeGenOpt::Level OptLevel,
47 bool AllocateGVsWithCode) {
48 const TargetMachineRegistry::entry *TheArch = MArch;
51 TheArch = TargetMachineRegistry::getClosestTargetForJIT(Error);
57 } else if (TheArch->JITMatchQualityFn() == 0) {
58 cerr << "WARNING: This target JIT is not designed for the host you are"
59 << " running. If bad things happen, please choose a different "
60 << "-march switch.\n";
63 // Package up features to be passed to target/subtarget
64 std::string FeaturesStr;
65 if (!MCPU.empty() || !MAttrs.empty()) {
66 SubtargetFeatures Features;
67 Features.setCPU(MCPU);
68 for (unsigned i = 0; i != MAttrs.size(); ++i)
69 Features.AddFeature(MAttrs[i]);
70 FeaturesStr = Features.getString();
73 // Allocate a target...
74 TargetMachine *Target = TheArch->CtorFn(*MP->getModule(), FeaturesStr);
75 assert(Target && "Could not allocate target machine!");
77 // If the target supports JIT code generation, return a new JIT now.
78 if (TargetJITInfo *TJ = Target->getJITInfo())
79 return new JIT(MP, *Target, *TJ, JMM, OptLevel, AllocateGVsWithCode);
82 *ErrorStr = "target does not support JIT code generation";