1 //===-- JIT.cpp - LLVM Just in Time Compiler ------------------------------===//
3 // This file implements the top-level support for creating a Just-In-Time
4 // compiler for the current architecture.
6 //===----------------------------------------------------------------------===//
9 #include "llvm/Target/TargetMachine.h"
10 #include "llvm/Target/TargetMachineImpls.h"
11 #include "llvm/Module.h"
12 #include "Support/CommandLine.h"
16 Arch("march", cl::desc("Architecture: `x86' or `sparc'"), cl::Prefix,
17 cl::value_desc("machine architecture"));
19 static std::string DefaultArch =
20 #if defined(i386) || defined(__i386__) || defined(__x86__)
22 #elif defined(sparc) || defined(__sparc__) || defined(__sparcv9)
31 /// createJIT - Create an return a new JIT compiler if there is one available
32 /// for the current target. Otherwise it returns null.
34 ExecutionEngine *ExecutionEngine::createJIT(Module *M, unsigned Config) {
36 TargetMachine* (*TargetMachineAllocator)(unsigned) = 0;
40 // Allow a command-line switch to override what *should* be the default target
41 // machine for this platform. This allows for debugging a Sparc JIT on X86 --
42 // our X86 machines are much faster at recompiling LLVM and linking lli.
44 TargetMachineAllocator = allocateX86TargetMachine;
45 } else if (Arch == "sparc") {
46 TargetMachineAllocator = allocateSparcTargetMachine;
49 if (TargetMachineAllocator) {
50 // Allocate a target...
51 TargetMachine *Target = (*TargetMachineAllocator)(Config);
52 assert(Target && "Could not allocate target machine!");
54 // Create the virtual machine object...
55 return new VM(M, Target);
61 VM::VM(Module *M, TargetMachine *tm) : ExecutionEngine(M), TM(*tm) {
62 setTargetData(TM.getTargetData());
66 MCE = createX86Emitter(*this);
67 } else if (Arch == "sparc") {
68 MCE = createSparcEmitter(*this);
76 int VM::run(const std::string &FnName, const std::vector<std::string> &Args) {
77 Function *F = getModule().getNamedFunction(FnName);
79 std::cerr << "Could not find function '" << FnName <<"' in module!\n";
83 int(*PF)(int, char**) = (int(*)(int, char**))getPointerToFunction(F);
84 assert(PF != 0 && "Null pointer to function?");
86 // Build an argv vector...
87 char **Argv = (char**)CreateArgv(Args);
89 // Call the main function...
90 int Result = PF(Args.size(), Argv);
92 // Run any atexit handlers now!