llvm-6502/lib/ExecutionEngine/JIT/JIT.cpp
Misha Brukman abb027cf41 Allow for specification of which JIT to run on the commandline.
`lli -march=x86' or `lli -march=sparc' will forcefully select the JIT even on a
different platform. Running lli without the -march option will select the JIT
for the platform that it's currently running on.

Pro: can test Sparc JIT (debug printing mode) on X86 -- faster to compile/link
LLVM source base to test changes.
Con: Linking lli on x86 now pulls in all the Sparc libs -> longer link time
(but X86 can bear it, right?)

In the future, perhaps this should be a ./configure option to enable/disable
target JITting...


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@6360 91177308-0d34-0410-b5e6-96231b3b80d8
2003-05-27 21:40:39 +00:00

96 lines
2.7 KiB
C++

//===-- JIT.cpp - LLVM Just in Time Compiler ------------------------------===//
//
// This file implements the top-level support for creating a Just-In-Time
// compiler for the current architecture.
//
//===----------------------------------------------------------------------===//
#include "VM.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetMachineImpls.h"
#include "llvm/Module.h"
#include "Support/CommandLine.h"
namespace {
cl::opt<std::string>
Arch("march", cl::desc("Architecture: `x86' or `sparc'"), cl::Prefix,
cl::value_desc("machine architecture"));
static std::string DefaultArch =
#if defined(i386) || defined(__i386__) || defined(__x86__)
"x86";
#elif defined(sparc) || defined(__sparc__) || defined(__sparcv9)
"sparc";
#else
"";
#endif
}
/// createJIT - Create an return a new JIT compiler if there is one available
/// for the current target. Otherwise it returns null.
///
ExecutionEngine *ExecutionEngine::createJIT(Module *M, unsigned Config) {
TargetMachine* (*TargetMachineAllocator)(unsigned) = 0;
if (Arch == "")
Arch = DefaultArch;
// Allow a command-line switch to override what *should* be the default target
// machine for this platform. This allows for debugging a Sparc JIT on X86 --
// our X86 machines are much faster at recompiling LLVM and linking lli.
if (Arch == "x86") {
TargetMachineAllocator = allocateX86TargetMachine;
} else if (Arch == "sparc") {
TargetMachineAllocator = allocateSparcTargetMachine;
}
if (TargetMachineAllocator) {
// Allocate a target...
TargetMachine *Target = (*TargetMachineAllocator)(Config);
assert(Target && "Could not allocate target machine!");
// Create the virtual machine object...
return new VM(M, Target);
} else {
return 0;
}
}
VM::VM(Module *M, TargetMachine *tm) : ExecutionEngine(M), TM(*tm) {
setTargetData(TM.getTargetData());
// Initialize MCE
if (Arch == "x86") {
MCE = createX86Emitter(*this);
} else if (Arch == "sparc") {
MCE = createSparcEmitter(*this);
}
setupPassManager();
registerCallback();
emitGlobals();
}
int VM::run(const std::string &FnName, const std::vector<std::string> &Args) {
Function *F = getModule().getNamedFunction(FnName);
if (F == 0) {
std::cerr << "Could not find function '" << FnName <<"' in module!\n";
return 1;
}
int(*PF)(int, char**) = (int(*)(int, char**))getPointerToFunction(F);
assert(PF != 0 && "Null pointer to function?");
// Build an argv vector...
char **Argv = (char**)CreateArgv(Args);
// Call the main function...
int Result = PF(Args.size(), Argv);
// Run any atexit handlers now!
runAtExitHandlers();
return Result;
}