llvm-6502/include/llvm/System/Memory.h

66 lines
2.3 KiB
C
Raw Normal View History

//===- llvm/System/Memory.h - Memory Support --------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Reid Spencer and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file declares the llvm::sys::Memory class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_SYSTEM_MEMORY_H
#define LLVM_SYSTEM_MEMORY_H
namespace llvm {
namespace sys {
/// This class encapsulates the notion of a memory block which has an address
/// and a size. It is used by the Memory class (a friend) as the result of
/// various memory allocation operations.
/// @see Memory
/// @brief Memory block abstraction.
class MemoryBlock {
public:
void* base() const { return Address; }
unsigned size() const { return Size; }
private:
void * Address; ///< Address of first byte of memory area
unsigned Size; ///< Size, in bytes of the memory area
friend class Memory;
};
/// This class provides various memory handling functions that manipulate
/// MemoryBlock instances.
/// @since 1.4
/// @brief An abstraction for memory operations.
class Memory {
/// @name Functions
/// @{
public:
/// This method allocates a block of Read/Write/Execute memory that is
/// suitable for executing dynamically generated code (e.g. JIT). An
/// attempt to allocate \p NumBytes bytes of virtual memory is made.
/// \p NearBlock may point to an existing allocation in which case
/// an attempt is made to allocate more memory near the existing block.
/// @throws std::string if an error occurred.
/// @brief Allocate Read/Write/Execute memory.
static MemoryBlock AllocateRWX(unsigned NumBytes, const MemoryBlock* NearBlock);
/// This method releases a block of Read/Write/Execute memory that was
/// allocated with the AllocateRWX method. It should not be used to
/// release any memory block allocated any other way.
/// @throws std::string if an error occurred.
/// @brief Release Read/Write/Execute memory.
static void ReleaseRWX(MemoryBlock& block);
/// @}
};
}
}
#endif