llvm/llvm/include/llvm/CodeGen/MachineBasicBlock.h

//===- llvm/CodeGen/MachineBasicBlock.h -------------------------*- 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
//
//===----------------------------------------------------------------------===//
//
// Collect the sequence of machine instructions for a basic block.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CODEGEN_MACHINEBASICBLOCK_H
#define LLVM_CODEGEN_MACHINEBASICBLOCK_H

#include "llvm/ADT/DenseMapInfo.h"
#include "llvm/ADT/GraphTraits.h"
#include "llvm/ADT/SparseBitVector.h"
#include "llvm/ADT/ilist.h"
#include "llvm/ADT/iterator_range.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBundleIterator.h"
#include "llvm/IR/DebugLoc.h"
#include "llvm/MC/LaneBitmask.h"
#include "llvm/Support/BranchProbability.h"
#include <cassert>
#include <cstdint>
#include <iterator>
#include <string>
#include <vector>

namespace llvm {

class BasicBlock;
class MachineFunction;
class MCSymbol;
class ModuleSlotTracker;
class Pass;
class Printable;
class SlotIndexes;
class StringRef;
class raw_ostream;
class LiveIntervals;
class TargetRegisterClass;
class TargetRegisterInfo;
template <typename IRUnitT, typename... ExtraArgTs> class AnalysisManager;
MachineFunctionAnalysisManager;

// This structure uniquely identifies a basic block section.
// Possible values are
//  {Type: Default, Number: (unsigned)} (These are regular section IDs)
//  {Type: Exception, Number: 0}  (ExceptionSectionID)
//  {Type: Cold, Number: 0}  (ColdSectionID)
struct MBBSectionID { … };

template <> struct DenseMapInfo<MBBSectionID> { … };

// This structure represents the information for a basic block pertaining to
// the basic block sections profile.
struct UniqueBBID { … };

template <> struct ilist_traits<MachineInstr> { … };

class MachineBasicBlock
    : public ilist_node_with_parent<MachineBasicBlock, MachineFunction> { … };

raw_ostream& operator<<(raw_ostream &OS, const MachineBasicBlock &MBB);

/// Prints a machine basic block reference.
///
/// The format is:
///   %bb.5           - a machine basic block with MBB.getNumber() == 5.
///
/// Usage: OS << printMBBReference(MBB) << '\n';
Printable printMBBReference(const MachineBasicBlock &MBB);

// This is useful when building IndexedMaps keyed on basic block pointers.
struct MBB2NumberFunctor { … };

//===--------------------------------------------------------------------===//
// GraphTraits specializations for machine basic block graphs (machine-CFGs)
//===--------------------------------------------------------------------===//

// Provide specializations of GraphTraits to be able to treat a
// MachineFunction as a graph of MachineBasicBlocks.
//

template <> struct GraphTraits<MachineBasicBlock *> { … };

static_assert …;

template <> struct GraphTraits<const MachineBasicBlock *> { … };

static_assert …;

// Provide specializations of GraphTraits to be able to treat a
// MachineFunction as a graph of MachineBasicBlocks and to walk it
// in inverse order.  Inverse order for a function is considered
// to be when traversing the predecessor edges of a MBB
// instead of the successor edges.
//
template <> struct GraphTraits<Inverse<MachineBasicBlock*>> { … };

static_assert …;

template <> struct GraphTraits<Inverse<const MachineBasicBlock*>> { … };

static_assert …;

// These accessors are handy for sharing templated code between IR and MIR.
inline auto successors(const MachineBasicBlock *BB) { … }
inline auto predecessors(const MachineBasicBlock *BB) { … }

/// MachineInstrSpan provides an interface to get an iteration range
/// containing the instruction it was initialized with, along with all
/// those instructions inserted prior to or following that instruction
/// at some point after the MachineInstrSpan is constructed.
class MachineInstrSpan { … };

/// Increment \p It until it points to a non-debug instruction or to \p End
/// and return the resulting iterator. This function should only be used
/// MachineBasicBlock::{iterator, const_iterator, instr_iterator,
/// const_instr_iterator} and the respective reverse iterators.
template <typename IterT>
inline IterT skipDebugInstructionsForward(IterT It, IterT End,
                                          bool SkipPseudoOp = true) { … }

/// Decrement \p It until it points to a non-debug instruction or to \p Begin
/// and return the resulting iterator. This function should only be used
/// MachineBasicBlock::{iterator, const_iterator, instr_iterator,
/// const_instr_iterator} and the respective reverse iterators.
template <class IterT>
inline IterT skipDebugInstructionsBackward(IterT It, IterT Begin,
                                           bool SkipPseudoOp = true) { … }

/// Increment \p It, then continue incrementing it while it points to a debug
/// instruction. A replacement for std::next.
template <typename IterT>
inline IterT next_nodbg(IterT It, IterT End, bool SkipPseudoOp = true) { … }

/// Decrement \p It, then continue decrementing it while it points to a debug
/// instruction. A replacement for std::prev.
template <typename IterT>
inline IterT prev_nodbg(IterT It, IterT Begin, bool SkipPseudoOp = true) { … }

/// Construct a range iterator which begins at \p It and moves forwards until
/// \p End is reached, skipping any debug instructions.
template <typename IterT>
inline auto instructionsWithoutDebug(IterT It, IterT End,
                                     bool SkipPseudoOp = true) { … }

} // end namespace llvm

#endif // LLVM_CODEGEN_MACHINEBASICBLOCK_H