blob: 33f3431a59a90e7e8a32e1cf84cee1c14a96815c [file] [log] [blame]
//===-- MCAtom.h ------------------------------------------------*- C++ -*-===//
// The LLVM Compiler Infrastructure
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
// This file contains the declaration of the MCAtom class, which is used to
// represent a contiguous region in a decoded object that is uniformly data or
// instructions.
#include "llvm/ADT/ArrayRef.h"
#include "llvm/MC/MCInst.h"
#include "llvm/Support/DataTypes.h"
#include <vector>
namespace llvm {
class MCModule;
class MCAtom;
class MCTextAtom;
class MCDataAtom;
/// \brief Represents a contiguous range of either instructions (a TextAtom)
/// or data (a DataAtom). Address ranges are expressed as _closed_ intervals.
class MCAtom {
virtual void anchor();
virtual ~MCAtom() {}
enum AtomKind { TextAtom, DataAtom };
AtomKind getKind() const { return Kind; }
/// \brief Get the start address of the atom.
uint64_t getBeginAddr() const { return Begin; }
/// \brief Get the end address, i.e. the last one inside the atom.
uint64_t getEndAddr() const { return End; }
/// \name Atom modification methods:
/// When modifying a TextAtom, keep instruction boundaries in mind.
/// For instance, split must me given the start address of an instruction.
/// @{
/// \brief Splits the atom in two at a given address.
/// \param SplitPt Address at which to start a new atom, splitting this one.
/// \returns The newly created atom starting at \p SplitPt.
virtual MCAtom *split(uint64_t SplitPt) = 0;
/// \brief Truncates an atom, discarding everything after \p TruncPt.
/// \param TruncPt Last byte address to be contained in this atom.
virtual void truncate(uint64_t TruncPt) = 0;
/// @}
/// \name Naming:
/// This is mostly for display purposes, and may contain anything that hints
/// at what the atom contains: section or symbol name, BB start address, ..
/// @{
StringRef getName() const { return Name; }
void setName(StringRef NewName) { Name = NewName.str(); }
/// @}
const AtomKind Kind;
std::string Name;
MCModule *Parent;
uint64_t Begin, End;
friend class MCModule;
MCAtom(AtomKind K, MCModule *P, uint64_t B, uint64_t E)
: Kind(K), Name("(unknown)"), Parent(P), Begin(B), End(E) { }
/// \name Atom remapping helpers
/// @{
/// \brief Remap the atom, using the given range, updating Begin/End.
/// One or both of the bounds can remain the same, but overlapping with other
/// atoms in the module is still forbidden.
void remap(uint64_t NewBegin, uint64_t NewEnd);
/// \brief Remap the atom to prepare for a truncation at TruncPt.
/// Equivalent to:
/// \code
/// // Bound checks
/// remap(Begin, TruncPt);
/// \endcode
void remapForTruncate(uint64_t TruncPt);
/// \brief Remap the atom to prepare for a split at SplitPt.
/// The bounds for the resulting atoms are returned in {L,R}{Begin,End}.
/// The current atom is truncated to \p LEnd.
void remapForSplit(uint64_t SplitPt,
uint64_t &LBegin, uint64_t &LEnd,
uint64_t &RBegin, uint64_t &REnd);
/// @}
/// \name Text atom
/// @{
/// \brief An entry in an MCTextAtom: a disassembled instruction.
/// NOTE: Both the Address and Size field are actually redundant when taken in
/// the context of the text atom, and may better be exposed in an iterator
/// instead of stored in the atom, which would replace this class.
class MCDecodedInst {
MCInst Inst;
uint64_t Address;
uint64_t Size;
MCDecodedInst(const MCInst &Inst, uint64_t Address, uint64_t Size)
: Inst(Inst), Address(Address), Size(Size) {}
/// \brief An atom consisting of disassembled instructions.
class MCTextAtom : public MCAtom {
typedef std::vector<MCDecodedInst> InstListTy;
InstListTy Insts;
/// \brief The address of the next appended instruction, i.e., the
/// address immediately after the last instruction in the atom.
uint64_t NextInstAddress;
/// Append an instruction, expanding the atom if necessary.
void addInst(const MCInst &Inst, uint64_t Size);
/// \name Instruction list access
/// @{
typedef InstListTy::const_iterator const_iterator;
const_iterator begin() const { return Insts.begin(); }
const_iterator end() const { return Insts.end(); }
const MCDecodedInst &back() const { return Insts.back(); }
const MCDecodedInst &at(size_t n) const { return; }
size_t size() const { return Insts.size(); }
/// @}
/// \name Atom type specific split/truncate logic.
/// @{
MCTextAtom *split(uint64_t SplitPt) override;
void truncate(uint64_t TruncPt) override;
/// @}
// Class hierarchy.
static bool classof(const MCAtom *A) { return A->getKind() == TextAtom; }
friend class MCModule;
// Private constructor - only callable by MCModule
MCTextAtom(MCModule *P, uint64_t Begin, uint64_t End)
: MCAtom(TextAtom, P, Begin, End), NextInstAddress(Begin) {}
/// @}
/// \name Data atom
/// @{
/// \brief An entry in an MCDataAtom.
// NOTE: This may change to a more complex type in the future.
typedef uint8_t MCData;
/// \brief An atom consising of a sequence of bytes.
class MCDataAtom : public MCAtom {
std::vector<MCData> Data;
/// Append a data entry, expanding the atom if necessary.
void addData(const MCData &D);
/// Get a reference to the data in this atom.
ArrayRef<MCData> getData() const { return Data; }
/// \name Atom type specific split/truncate logic.
/// @{
MCDataAtom *split(uint64_t SplitPt) override;
void truncate(uint64_t TruncPt) override;
/// @}
// Class hierarchy.
static bool classof(const MCAtom *A) { return A->getKind() == DataAtom; }
friend class MCModule;
// Private constructor - only callable by MCModule
MCDataAtom(MCModule *P, uint64_t Begin, uint64_t End)
: MCAtom(DataAtom, P, Begin, End) {
Data.reserve(End + 1 - Begin);