llvm/llvm/include/llvm/MC/MCContext.h

//===- MCContext.h - Machine Code Context -----------------------*- 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
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_MC_MCCONTEXT_H
#define LLVM_MC_MCCONTEXT_H

#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Twine.h"
#include "llvm/BinaryFormat/Dwarf.h"
#include "llvm/BinaryFormat/XCOFF.h"
#include "llvm/MC/MCAsmMacro.h"
#include "llvm/MC/MCDwarf.h"
#include "llvm/MC/MCPseudoProbe.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCSymbolTableEntry.h"
#include "llvm/MC/SectionKind.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/MD5.h"
#include "llvm/Support/StringSaver.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cassert>
#include <cstddef>
#include <cstdint>
#include <functional>
#include <map>
#include <memory>
#include <optional>
#include <string>
#include <utility>
#include <vector>

namespace llvm {

class CodeViewContext;
class MCAsmInfo;
class MCDataFragment;
class MCInst;
class MCLabel;
class MCObjectFileInfo;
class MCRegisterInfo;
class MCSection;
class MCSectionCOFF;
class MCSectionDXContainer;
class MCSectionELF;
class MCSectionGOFF;
class MCSectionMachO;
class MCSectionSPIRV;
class MCSectionWasm;
class MCSectionXCOFF;
class MCStreamer;
class MCSubtargetInfo;
class MCSymbol;
class MCSymbolELF;
class MCSymbolWasm;
class MCSymbolXCOFF;
class MCTargetOptions;
class MDNode;
template <typename T> class SmallVectorImpl;
class SMDiagnostic;
class SMLoc;
class SourceMgr;
enum class EmitDwarfUnwindType;

namespace wasm {
struct WasmSignature;
}

/// Context object for machine code objects.  This class owns all of the
/// sections that it creates.
///
class MCContext { … };

} // end namespace llvm

// operator new and delete aren't allowed inside namespaces.
// The throw specifications are mandated by the standard.
/// Placement new for using the MCContext's allocator.
///
/// This placement form of operator new uses the MCContext's allocator for
/// obtaining memory. It is a non-throwing new, which means that it returns
/// null on error. (If that is what the allocator does. The current does, so if
/// this ever changes, this operator will have to be changed, too.)
/// Usage looks like this (assuming there's an MCContext 'Context' in scope):
/// \code
/// // Default alignment (8)
/// IntegerLiteral *Ex = new (Context) IntegerLiteral(arguments);
/// // Specific alignment
/// IntegerLiteral *Ex2 = new (Context, 4) IntegerLiteral(arguments);
/// \endcode
/// Please note that you cannot use delete on the pointer; it must be
/// deallocated using an explicit destructor call followed by
/// \c Context.Deallocate(Ptr).
///
/// \param Bytes The number of bytes to allocate. Calculated by the compiler.
/// \param C The MCContext that provides the allocator.
/// \param Alignment The alignment of the allocated memory (if the underlying
///                  allocator supports it).
/// \return The allocated memory. Could be NULL.
inline void *operator new(size_t Bytes, llvm::MCContext &C,
                          size_t Alignment = 8) noexcept { … }
/// Placement delete companion to the new above.
///
/// This operator is just a companion to the new above. There is no way of
/// invoking it directly; see the new operator for more details. This operator
/// is called implicitly by the compiler if a placement new expression using
/// the MCContext throws in the object constructor.
inline void operator delete(void *Ptr, llvm::MCContext &C, size_t) noexcept { … }

/// This placement form of operator new[] uses the MCContext's allocator for
/// obtaining memory. It is a non-throwing new[], which means that it returns
/// null on error.
/// Usage looks like this (assuming there's an MCContext 'Context' in scope):
/// \code
/// // Default alignment (8)
/// char *data = new (Context) char[10];
/// // Specific alignment
/// char *data = new (Context, 4) char[10];
/// \endcode
/// Please note that you cannot use delete on the pointer; it must be
/// deallocated using an explicit destructor call followed by
/// \c Context.Deallocate(Ptr).
///
/// \param Bytes The number of bytes to allocate. Calculated by the compiler.
/// \param C The MCContext that provides the allocator.
/// \param Alignment The alignment of the allocated memory (if the underlying
///                  allocator supports it).
/// \return The allocated memory. Could be NULL.
inline void *operator new[](size_t Bytes, llvm::MCContext &C,
                            size_t Alignment = 8) noexcept { … }

/// Placement delete[] companion to the new[] above.
///
/// This operator is just a companion to the new[] above. There is no way of
/// invoking it directly; see the new[] operator for more details. This operator
/// is called implicitly by the compiler if a placement new[] expression using
/// the MCContext throws in the object constructor.
inline void operator delete[](void *Ptr, llvm::MCContext &C) noexcept { … }

#endif // LLVM_MC_MCCONTEXT_H