1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
//===- examples/ModuleMaker/ModuleMaker.cpp - Example project ---*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This programs is a simple example that creates an LLVM module "from scratch",
// emitting it as a bitcode file to standard out. This is just to show how
// LLVM projects work and to demonstrate some of the LLVM APIs.
//
//===----------------------------------------------------------------------===//
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
int main() {
LLVMContext Context;
// Create the "module" or "program" or "translation unit" to hold the
// function
Module *M = new Module("test", Context);
// Create the main function: first create the type 'int ()'
FunctionType *FT =
FunctionType::get(Type::getInt32Ty(Context), /*not vararg*/false);
// By passing a module as the last parameter to the Function constructor,
// it automatically gets appended to the Module.
Function *F = Function::Create(FT, Function::ExternalLinkage, "main", M);
// Add a basic block to the function... again, it automatically inserts
// because of the last argument.
BasicBlock *BB = BasicBlock::Create(Context, "EntryBlock", F);
// Get pointers to the constant integers...
Value *Two = ConstantInt::get(Type::getInt32Ty(Context), 2);
Value *Three = ConstantInt::get(Type::getInt32Ty(Context), 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(ReturnInst::Create(Context, Add));
// Output the bitcode file to stdout
WriteBitcodeToFile(M, outs());
// Delete the module and all of its contents.
delete M;
return 0;
}
|
