llvm-6502/lib/ExecutionEngine/Interpreter/Interpreter.cpp

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//===- Interpreter.cpp - Top-Level LLVM Interpreter Implementation --------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the top-level functionality for the LLVM interpreter.
// This interpreter is designed to be a very simple, portable, inefficient
// interpreter.
//
//===----------------------------------------------------------------------===//
#include "Interpreter.h"
#include "llvm/CodeGen/IntrinsicLowering.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/ModuleProvider.h"
using namespace llvm;
static struct RegisterInterp {
RegisterInterp() { Interpreter::Register(); }
} InterpRegistrator;
namespace llvm {
void LinkInInterpreter() {
}
}
/// create - Create a new interpreter object. This can never fail.
///
ExecutionEngine *Interpreter::create(ModuleProvider *MP) {
Module *M;
try {
M = MP->materializeModule();
} catch (...) {
return 0; // error materializing the module.
}
if (M->getEndianness() == Module::AnyEndianness) {
int Test = 0;
*(char*)&Test = 1; // Return true if the host is little endian
bool isLittleEndian = (Test == 1);
M->setEndianness(isLittleEndian ? Module::LittleEndian : Module::BigEndian);
}
if (M->getPointerSize() == Module::AnyPointerSize) {
// Follow host.
bool Ptr64 = sizeof(void*) == 8;
M->setPointerSize(Ptr64 ? Module::Pointer64 : Module::Pointer32);
}
return new Interpreter(M);
}
//===----------------------------------------------------------------------===//
// Interpreter ctor - Initialize stuff
//
Interpreter::Interpreter(Module *M) : ExecutionEngine(M), TD(M) {
memset(&ExitValue, 0, sizeof(ExitValue));
setTargetData(&TD);
// Initialize the "backend"
initializeExecutionEngine();
initializeExternalFunctions();
emitGlobals();
IL = new DefaultIntrinsicLowering();
}
Interpreter::~Interpreter() {
delete IL;
}
void Interpreter::runAtExitHandlers () {
while (!AtExitHandlers.empty()) {
callFunction(AtExitHandlers.back(), std::vector<GenericValue>());
AtExitHandlers.pop_back();
run();
}
}
/// run - Start execution with the specified function and arguments.
///
GenericValue
Interpreter::runFunction(Function *F,
const std::vector<GenericValue> &ArgValues) {
assert (F && "Function *F was null at entry to run()");
// Try extra hard not to pass extra args to a function that isn't
// expecting them. C programmers frequently bend the rules and
// declare main() with fewer parameters than it actually gets
// passed, and the interpreter barfs if you pass a function more
// parameters than it is declared to take. This does not attempt to
// take into account gratuitous differences in declared types,
// though.
std::vector<GenericValue> ActualArgs;
const unsigned ArgCount = F->getFunctionType()->getNumParams();
for (unsigned i = 0; i < ArgCount; ++i)
ActualArgs.push_back(ArgValues[i]);
// Set up the function call.
callFunction(F, ActualArgs);
// Start executing the function.
run();
return ExitValue;
}