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//===- ModuleMaker.cpp - Example project which creates modules --*- C++ -*-===//
//
// This programs is a simple example that creates an LLVM module "from scratch",
// emitting it as a bytecode file to standard out. This is just to show how
// LLVM projects work and to demonstrate some of the LLVM APIs.
//
//===----------------------------------------------------------------------===//
#include "llvm/Module.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Constants.h"
#include "llvm/Instructions.h"
#include "llvm/Bytecode/Writer.h"
int main() {
// Create the "module" or "program" or "translation unit" to hold the
// function
Module *M = new Module("test");
// Create the main function: first create the type 'int ()'
FunctionType *FT = FunctionType::get(Type::IntTy, std::vector<const Type*>(),
/*not vararg*/false);
// By passing a module as the last parameter to the Function constructor,
// it automatically gets appended to the Module.
Function *F = new Function(FT, Function::ExternalLinkage, "main", M);
// Add a basic block to the function... again, it automatically inserts
// because of the last argument.
BasicBlock *BB = new BasicBlock("EntryBlock", F);
// Get pointers to the constant integers...
Value *Two = ConstantSInt::get(Type::IntTy, 2);
Value *Three = ConstantSInt::get(Type::IntTy, 3);
// Create the add instruction... does not insert...
Instruction *Add = BinaryOperator::create(Instruction::Add, Two, Three,
"addresult");
// explicitly insert it into the basic block...
BB->getInstList().push_back(Add);
// Create the return instruction and add it to the basic block
BB->getInstList().push_back(new ReturnInst(Add));
// Output the bytecode file to stdout
WriteBytecodeToFile(M, std::cout);
// Delete the module and all of its contents.
delete M;
return 0;
}
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