LLVM将函数调用插入另一个函数

cmake_minimum_required(VERSION 3.10)
project(LLVMInsertFunctionCall)

find_package(LLVM REQUIRED CONFIG)
list(APPEND CMAKE_MODULE_PATH "${LLVM_CMAKE_DIR}")
include(AddLLVM)

include_directories(${LLVM_INCLUDE_DIRS})
add_definitions(${LLVM_DEFINITIONS})

add_executable(LLVMInsertFunctionCall main.cpp)

llvm_map_components_to_libnames(llvm_libs support core irreader)
target_link_libraries(LLVMInsertFunctionCall ${llvm_libs})

#include <llvm/IR/IRBuilder.h>
#include <llvm/IR/LLVMContext.h>
#include <llvm/IR/Module.h>
#include <llvm/IR/Function.h>
#include <llvm/IR/Type.h>
#include <llvm/IR/Verifier.h>
#include <llvm/Support/raw_ostream.h>

using namespace llvm;

int main() {
    LLVMContext Context;
    Module *M = new Module("test", Context);
    IRBuilder<> Builder(Context);

    // 创建函数类型：void foo()
    FunctionType *fooType = FunctionType::get(Type::getVoidTy(Context), false);
    Function *fooFunc = Function::Create(fooType, Function::ExternalLinkage, "foo", M);

    // 创建函数类型：void bar()
    FunctionType *barType = FunctionType::get(Type::getVoidTy(Context), false);
    Function *barFunc = Function::Create(barType, Function::ExternalLinkage, "bar", M);

    // 创建 foo 函数的基本块
    BasicBlock *fooBB = BasicBlock::Create(Context, "entry", fooFunc);
    Builder.SetInsertPoint(fooBB);

    // 在 foo 函数中插入对 bar 的调用
    Builder.CreateCall(barFunc);

    // 在 foo 函数中插入返回指令
    Builder.CreateRetVoid();

    // 验证生成的代码
    if (verifyFunction(*fooFunc, &errs())) {
        errs() << "Function verification failed!\n";
        return 1;
    }

    // 打印生成的 LLVM IR
    M->print(outs(), nullptr);

    delete M;
    return 0;
}

; ModuleID = 'test'
source_filename = "test"

define void @foo() {
entry:
  call void @bar()
  ret void
}

define void @bar() {
}