mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-11-09 10:05:41 +00:00
674be02d52
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172025 91177308-0d34-0410-b5e6-96231b3b80d8
162 lines
6.8 KiB
C++
162 lines
6.8 KiB
C++
//===- llvm/Support/Memory.h - Memory Support --------------------*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file 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_SUPPORT_MEMORY_H
|
|
#define LLVM_SUPPORT_MEMORY_H
|
|
|
|
#include "llvm/Support/DataTypes.h"
|
|
#include "llvm/Support/system_error.h"
|
|
#include <string>
|
|
|
|
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:
|
|
MemoryBlock() : Address(0), Size(0) { }
|
|
MemoryBlock(void *addr, size_t size) : Address(addr), Size(size) { }
|
|
void *base() const { return Address; }
|
|
size_t size() const { return Size; }
|
|
private:
|
|
void *Address; ///< Address of first byte of memory area
|
|
size_t 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 {
|
|
public:
|
|
enum ProtectionFlags {
|
|
MF_READ = 0x1000000,
|
|
MF_WRITE = 0x2000000,
|
|
MF_EXEC = 0x4000000
|
|
};
|
|
|
|
/// This method allocates a block of memory that is suitable for loading
|
|
/// 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.
|
|
/// The actual allocated address is not guaranteed to be near the requested
|
|
/// address.
|
|
/// \p Flags is used to set the initial protection flags for the block
|
|
/// of the memory.
|
|
/// \p EC [out] returns an object describing any error that occurs.
|
|
///
|
|
/// This method may allocate more than the number of bytes requested. The
|
|
/// actual number of bytes allocated is indicated in the returned
|
|
/// MemoryBlock.
|
|
///
|
|
/// The start of the allocated block must be aligned with the
|
|
/// system allocation granularity (64K on Windows, page size on Linux).
|
|
/// If the address following \p NearBlock is not so aligned, it will be
|
|
/// rounded up to the next allocation granularity boundary.
|
|
///
|
|
/// \r a non-null MemoryBlock if the function was successful,
|
|
/// otherwise a null MemoryBlock is with \p EC describing the error.
|
|
///
|
|
/// @brief Allocate mapped memory.
|
|
static MemoryBlock allocateMappedMemory(size_t NumBytes,
|
|
const MemoryBlock *const NearBlock,
|
|
unsigned Flags,
|
|
error_code &EC);
|
|
|
|
/// This method releases a block of memory that was allocated with the
|
|
/// allocateMappedMemory method. It should not be used to release any
|
|
/// memory block allocated any other way.
|
|
/// \p Block describes the memory to be released.
|
|
///
|
|
/// \r error_success if the function was successful, or an error_code
|
|
/// describing the failure if an error occurred.
|
|
///
|
|
/// @brief Release mapped memory.
|
|
static error_code releaseMappedMemory(MemoryBlock &Block);
|
|
|
|
/// This method sets the protection flags for a block of memory to the
|
|
/// state specified by /p Flags. The behavior is not specified if the
|
|
/// memory was not allocated using the allocateMappedMemory method.
|
|
/// \p Block describes the memory block to be protected.
|
|
/// \p Flags specifies the new protection state to be assigned to the block.
|
|
/// \p ErrMsg [out] returns a string describing any error that occured.
|
|
///
|
|
/// If \p Flags is MF_WRITE, the actual behavior varies
|
|
/// with the operating system (i.e. MF_READ | MF_WRITE on Windows) and the
|
|
/// target architecture (i.e. MF_WRITE -> MF_READ | MF_WRITE on i386).
|
|
///
|
|
/// \r error_success if the function was successful, or an error_code
|
|
/// describing the failure if an error occurred.
|
|
///
|
|
/// @brief Set memory protection state.
|
|
static error_code protectMappedMemory(const MemoryBlock &Block,
|
|
unsigned Flags);
|
|
|
|
/// 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.
|
|
///
|
|
/// On success, this returns a non-null memory block, otherwise it returns
|
|
/// a null memory block and fills in *ErrMsg.
|
|
///
|
|
/// @brief Allocate Read/Write/Execute memory.
|
|
static MemoryBlock AllocateRWX(size_t NumBytes,
|
|
const MemoryBlock *NearBlock,
|
|
std::string *ErrMsg = 0);
|
|
|
|
/// 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.
|
|
///
|
|
/// On success, this returns false, otherwise it returns true and fills
|
|
/// in *ErrMsg.
|
|
/// @brief Release Read/Write/Execute memory.
|
|
static bool ReleaseRWX(MemoryBlock &block, std::string *ErrMsg = 0);
|
|
|
|
|
|
/// InvalidateInstructionCache - Before the JIT can run a block of code
|
|
/// that has been emitted it must invalidate the instruction cache on some
|
|
/// platforms.
|
|
static void InvalidateInstructionCache(const void *Addr, size_t Len);
|
|
|
|
/// setExecutable - Before the JIT can run a block of code, it has to be
|
|
/// given read and executable privilege. Return true if it is already r-x
|
|
/// or the system is able to change its previlege.
|
|
static bool setExecutable(MemoryBlock &M, std::string *ErrMsg = 0);
|
|
|
|
/// setWritable - When adding to a block of code, the JIT may need
|
|
/// to mark a block of code as RW since the protections are on page
|
|
/// boundaries, and the JIT internal allocations are not page aligned.
|
|
static bool setWritable(MemoryBlock &M, std::string *ErrMsg = 0);
|
|
|
|
/// setRangeExecutable - Mark the page containing a range of addresses
|
|
/// as executable.
|
|
static bool setRangeExecutable(const void *Addr, size_t Size);
|
|
|
|
/// setRangeWritable - Mark the page containing a range of addresses
|
|
/// as writable.
|
|
static bool setRangeWritable(const void *Addr, size_t Size);
|
|
};
|
|
}
|
|
}
|
|
|
|
#endif
|