mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-24 03:33:20 +01:00
69 lines
3.0 KiB
C++
69 lines
3.0 KiB
C++
//===- MemoryObject.h - Abstract memory interface ---------------*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_SUPPORT_MEMORYOBJECT_H
|
|
#define LLVM_SUPPORT_MEMORYOBJECT_H
|
|
|
|
#include "llvm/Support/DataTypes.h"
|
|
|
|
namespace llvm {
|
|
|
|
/// Interface to data which might be streamed. Streamability has 2 important
|
|
/// implications/restrictions. First, the data might not yet exist in memory
|
|
/// when the request is made. This just means that readByte/readBytes might have
|
|
/// to block or do some work to get it. More significantly, the exact size of
|
|
/// the object might not be known until it has all been fetched. This means that
|
|
/// to return the right result, getExtent must also wait for all the data to
|
|
/// arrive; therefore it should not be called on objects which are actually
|
|
/// streamed (this would defeat the purpose of streaming). Instead,
|
|
/// isValidAddress can be used to test addresses without knowing the exact size
|
|
/// of the stream. Finally, getPointer can be used instead of readBytes to avoid
|
|
/// extra copying.
|
|
class MemoryObject {
|
|
public:
|
|
virtual ~MemoryObject();
|
|
|
|
/// Returns the size of the region in bytes. (The region is contiguous, so
|
|
/// the highest valid address of the region is getExtent() - 1).
|
|
///
|
|
/// @result - The size of the region.
|
|
virtual uint64_t getExtent() const = 0;
|
|
|
|
/// Tries to read a contiguous range of bytes from the region, up to the end
|
|
/// of the region.
|
|
///
|
|
/// @param Buf - A pointer to a buffer to be filled in. Must be non-NULL
|
|
/// and large enough to hold size bytes.
|
|
/// @param Size - The number of bytes to copy.
|
|
/// @param Address - The address of the first byte, in the same space as
|
|
/// getBase().
|
|
/// @result - The number of bytes read.
|
|
virtual uint64_t readBytes(uint8_t *Buf, uint64_t Size,
|
|
uint64_t Address) const = 0;
|
|
|
|
/// Ensures that the requested data is in memory, and returns a pointer to it.
|
|
/// More efficient than using readBytes if the data is already in memory. May
|
|
/// block until (address - base + size) bytes have been read
|
|
/// @param address - address of the byte, in the same space as getBase()
|
|
/// @param size - amount of data that must be available on return
|
|
/// @result - valid pointer to the requested data
|
|
virtual const uint8_t *getPointer(uint64_t address, uint64_t size) const = 0;
|
|
|
|
/// Returns true if the address is within the object (i.e. between base and
|
|
/// base + extent - 1 inclusive). May block until (address - base) bytes have
|
|
/// been read
|
|
/// @param address - address of the byte, in the same space as getBase()
|
|
/// @result - true if the address may be read with readByte()
|
|
virtual bool isValidAddress(uint64_t address) const = 0;
|
|
};
|
|
|
|
}
|
|
|
|
#endif
|