1 //===-- TargetSelect.cpp - Target Chooser Code ----------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source 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/Target/SubtargetFeature.h"
19 #include "llvm/Target/TargetMachine.h"
20 #include "llvm/Target/TargetMachineRegistry.h"
23 static cl::opt<const TargetMachineRegistry::entry*, false,
24 TargetMachineRegistry::Parser>
25 MArch("march", cl::desc("Architecture to generate assembly for:"));
27 static cl::opt<std::string>
29 cl::desc("Target a specific cpu type (-mcpu=help for details)"),
30 cl::value_desc("cpu-name"),
33 static cl::list<std::string>
36 cl::desc("Target specific attributes (-mattr=help for details)"),
37 cl::value_desc("a1,+a2,-a3,..."));
39 /// createInternal - Create an return a new JIT compiler if there is one
40 /// available for the current target. Otherwise, return null.
42 ExecutionEngine *JIT::createJIT(ModuleProvider *MP, std::string *ErrorStr,
43 JITMemoryManager *JMM) {
44 const TargetMachineRegistry::entry *TheArch = MArch;
47 TheArch = TargetMachineRegistry::getClosestTargetForJIT(Error);
53 } else if (TheArch->JITMatchQualityFn() == 0) {
54 cerr << "WARNING: This target JIT is not designed for the host you are"
55 << " running. If bad things happen, please choose a different "
56 << "-march switch.\n";
59 // Package up features to be passed to target/subtarget
60 std::string FeaturesStr;
61 if (MCPU.size() || MAttrs.size()) {
62 SubtargetFeatures Features;
63 Features.setCPU(MCPU);
64 for (unsigned i = 0; i != MAttrs.size(); ++i)
65 Features.AddFeature(MAttrs[i]);
66 FeaturesStr = Features.getString();
69 // Allocate a target...
70 TargetMachine *Target = TheArch->CtorFn(*MP->getModule(), FeaturesStr);
71 assert(Target && "Could not allocate target machine!");
73 // If the target supports JIT code generation, return a new JIT now.
74 if (TargetJITInfo *TJ = Target->getJITInfo())
75 return new JIT(MP, *Target, *TJ, JMM);
78 *ErrorStr = "target does not support JIT code generation";