ModuleMaker.cpp revision 051a950000e21935165db56695e35bade668193b
166e7cd0eea6f116f3ed79acb8948c6d8db50833cReid Spencer//===- examples/ModuleMaker/ModuleMaker.cpp - Example project ---*- C++ -*-===// 2237cef4b0b94b17ca065efad484f386f42579b61Misha Brukman// 37db7fa0828bc4ac375032a847b3fd530cef131e2Chris Lattner// The LLVM Compiler Infrastructure 47db7fa0828bc4ac375032a847b3fd530cef131e2Chris Lattner// 5fc001bbfc360ab828e5a4b0cbe4bb7db87361b85Chris Lattner// This file is distributed under the University of Illinois Open Source 6fc001bbfc360ab828e5a4b0cbe4bb7db87361b85Chris Lattner// License. See LICENSE.TXT for details. 7237cef4b0b94b17ca065efad484f386f42579b61Misha Brukman// 87db7fa0828bc4ac375032a847b3fd530cef131e2Chris Lattner//===----------------------------------------------------------------------===// 98ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner// 108ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner// This programs is a simple example that creates an LLVM module "from scratch", 11a99be51bf5cdac1438069d4b01766c47704961c8Gabor Greif// emitting it as a bitcode file to standard out. This is just to show how 128ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner// LLVM projects work and to demonstrate some of the LLVM APIs. 138ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner// 148ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner//===----------------------------------------------------------------------===// 158ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner 168ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner#include "llvm/Module.h" 178ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner#include "llvm/DerivedTypes.h" 188ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner#include "llvm/Constants.h" 198ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner#include "llvm/Instructions.h" 204bcca0f2ac85c918fc8617e34b7642e5e5233460Chris Lattner#include "llvm/Bitcode/ReaderWriter.h" 214bcca0f2ac85c918fc8617e34b7642e5e5233460Chris Lattner#include <iostream> 22d0fde30ce850b78371fd1386338350591f9ff494Brian Gaekeusing namespace llvm; 23d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 248ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattnerint main() { 258ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // Create the "module" or "program" or "translation unit" to hold the 268ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // function 278ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner Module *M = new Module("test"); 28237cef4b0b94b17ca065efad484f386f42579b61Misha Brukman 298ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // Create the main function: first create the type 'int ()' 30db8d2bed6a0ef890b81fabb014bfcb678e891695Reid Spencer FunctionType *FT = FunctionType::get(Type::Int32Ty, std::vector<const Type*>(), 318ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner /*not vararg*/false); 32237cef4b0b94b17ca065efad484f386f42579b61Misha Brukman 338ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // By passing a module as the last parameter to the Function constructor, 348ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // it automatically gets appended to the Module. 35051a950000e21935165db56695e35bade668193bGabor Greif Function *F = Function::Create(FT, Function::ExternalLinkage, "main", M); 36237cef4b0b94b17ca065efad484f386f42579b61Misha Brukman 378ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // Add a basic block to the function... again, it automatically inserts 388ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // because of the last argument. 39051a950000e21935165db56695e35bade668193bGabor Greif BasicBlock *BB = BasicBlock::Create("EntryBlock", F); 40237cef4b0b94b17ca065efad484f386f42579b61Misha Brukman 418ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // Get pointers to the constant integers... 42db8d2bed6a0ef890b81fabb014bfcb678e891695Reid Spencer Value *Two = ConstantInt::get(Type::Int32Ty, 2); 43db8d2bed6a0ef890b81fabb014bfcb678e891695Reid Spencer Value *Three = ConstantInt::get(Type::Int32Ty, 3); 44237cef4b0b94b17ca065efad484f386f42579b61Misha Brukman 458ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // Create the add instruction... does not insert... 468ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner Instruction *Add = BinaryOperator::create(Instruction::Add, Two, Three, 478ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner "addresult"); 48237cef4b0b94b17ca065efad484f386f42579b61Misha Brukman 498ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // explicitly insert it into the basic block... 508ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner BB->getInstList().push_back(Add); 51237cef4b0b94b17ca065efad484f386f42579b61Misha Brukman 528ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // Create the return instruction and add it to the basic block 53051a950000e21935165db56695e35bade668193bGabor Greif BB->getInstList().push_back(ReturnInst::Create(Add)); 54237cef4b0b94b17ca065efad484f386f42579b61Misha Brukman 55a99be51bf5cdac1438069d4b01766c47704961c8Gabor Greif // Output the bitcode file to stdout 564bcca0f2ac85c918fc8617e34b7642e5e5233460Chris Lattner WriteBitcodeToFile(M, std::cout); 57237cef4b0b94b17ca065efad484f386f42579b61Misha Brukman 588ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner // Delete the module and all of its contents. 598ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner delete M; 608ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner return 0; 618ca0eebe4ef4fe810dba5ce91306031272f139cfChris Lattner} 62