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Diffstat (limited to 'examples/ModuleMaker/ModuleMaker.cpp')
-rw-r--r-- | examples/ModuleMaker/ModuleMaker.cpp | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/examples/ModuleMaker/ModuleMaker.cpp b/examples/ModuleMaker/ModuleMaker.cpp new file mode 100644 index 0000000..1d06c2d --- /dev/null +++ b/examples/ModuleMaker/ModuleMaker.cpp @@ -0,0 +1,52 @@ +//===- 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; +} |