llvm/llvm/lib/Transforms/Utils/CtorUtils.cpp

//===- CtorUtils.cpp - Helpers for working with global_ctors ----*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines functions that are used to process llvm.global_ctors.
//
//===----------------------------------------------------------------------===//

#include "llvm/Transforms/Utils/CtorUtils.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include <numeric>

#define DEBUG_TYPE …

usingnamespacellvm;

/// Given a specified llvm.global_ctors list, remove the listed elements.
static void removeGlobalCtors(GlobalVariable *GCL, const BitVector &CtorsToRemove) { … }

/// Given a llvm.global_ctors list that we can understand,
/// return a list of the functions and null terminator as a vector.
static std::vector<std::pair<uint32_t, Function *>>
parseGlobalCtors(GlobalVariable *GV) { … }

/// Find the llvm.global_ctors list.
static GlobalVariable *findGlobalCtors(Module &M) { … }

/// Call "ShouldRemove" for every entry in M's global_ctor list and remove the
/// entries for which it returns true.  Return true if anything changed.
bool llvm::optimizeGlobalCtorsList(
    Module &M, function_ref<bool(uint32_t, Function *)> ShouldRemove) { … }