llvm/llvm/include/llvm/IR/BasicBlock.h

//===- llvm/BasicBlock.h - Represent a basic block in the VM ----*- 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 contains the declaration of the BasicBlock class.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_IR_BASICBLOCK_H
#define LLVM_IR_BASICBLOCK_H

#include "llvm-c/Types.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/Twine.h"
#include "llvm/ADT/ilist.h"
#include "llvm/ADT/ilist_node.h"
#include "llvm/ADT/iterator.h"
#include "llvm/ADT/iterator_range.h"
#include "llvm/IR/DebugProgramInstruction.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/SymbolTableListTraits.h"
#include "llvm/IR/Value.h"
#include <cassert>
#include <cstddef>
#include <iterator>

namespace llvm {

class AssemblyAnnotationWriter;
class CallInst;
class DataLayout;
class Function;
class LandingPadInst;
class LLVMContext;
class Module;
class PHINode;
class ValueSymbolTable;
class DbgVariableRecord;
class DbgMarker;

/// LLVM Basic Block Representation
///
/// This represents a single basic block in LLVM. A basic block is simply a
/// container of instructions that execute sequentially. Basic blocks are Values
/// because they are referenced by instructions such as branches and switch
/// tables. The type of a BasicBlock is "Type::LabelTy" because the basic block
/// represents a label to which a branch can jump.
///
/// A well formed basic block is formed of a list of non-terminating
/// instructions followed by a single terminator instruction. Terminator
/// instructions may not occur in the middle of basic blocks, and must terminate
/// the blocks. The BasicBlock class allows malformed basic blocks to occur
/// because it may be useful in the intermediate stage of constructing or
/// modifying a program. However, the verifier will ensure that basic blocks are
/// "well formed".
class BasicBlock final : public Value, // Basic blocks are data objects also
                         public ilist_node_with_parent<BasicBlock, Function> { … };

// Create wrappers for C Binding types (see CBindingWrapping.h).
DEFINE_SIMPLE_CONVERSION_FUNCTIONS(…)

/// Advance \p It while it points to a debug instruction and return the result.
/// This assumes that \p It is not at the end of a block.
BasicBlock::iterator skipDebugIntrinsics(BasicBlock::iterator It);

#ifdef NDEBUG
/// In release builds, this is a no-op. For !NDEBUG builds, the checks are
/// implemented in the .cpp file to avoid circular header deps.
inline void BasicBlock::validateInstrOrdering() const { … }
#endif

// Specialize DenseMapInfo for iterators, so that ththey can be installed into
// maps and sets. The iterator is made up of its node pointer, and the
// debug-info "head" bit.
template <> struct DenseMapInfo<BasicBlock::iterator> { … };

} // end namespace llvm

#endif // LLVM_IR_BASICBLOCK_H