gem5/src/cpu/o3/rename_map.hh

168 lines
5.3 KiB
C++

/*
* Copyright (c) 2004-2005 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Kevin Lim
*/
// Todo: Create destructor.
// Have it so that there's a more meaningful name given to the variable
// that marks the beginning of the FP registers.
#ifndef __CPU_O3_RENAME_MAP_HH__
#define __CPU_O3_RENAME_MAP_HH__
#include <iostream>
#include <utility>
#include <vector>
#include "arch/types.hh"
#include "config/the_isa.hh"
#include "cpu/o3/free_list.hh"
class SimpleRenameMap
{
protected:
typedef TheISA::RegIndex RegIndex;
public:
/**
* Pair of a logical register and a physical register. Tells the
* previous mapping of a logical register to a physical register.
* Used to roll back the rename map to a previous state.
*/
typedef std::pair<RegIndex, PhysRegIndex> UnmapInfo;
/**
* Pair of a physical register and a physical register. Used to
* return the physical register that a logical register has been
* renamed to, and the previous physical register that the same
* logical register was previously mapped to.
*/
typedef std::pair<PhysRegIndex, PhysRegIndex> RenameInfo;
public:
/** Default constructor. init() must be called prior to use. */
SimpleRenameMap() {};
/** Destructor. */
~SimpleRenameMap();
/** Initializes rename map with given parameters. */
void init(unsigned _numLogicalIntRegs,
unsigned _numPhysicalIntRegs,
PhysRegIndex &_int_reg_start,
unsigned _numLogicalFloatRegs,
unsigned _numPhysicalFloatRegs,
PhysRegIndex &_float_reg_start,
unsigned _numMiscRegs,
RegIndex _intZeroReg,
RegIndex _floatZeroReg,
int id,
bool bindRegs);
/** Sets the free list used with this rename map. */
void setFreeList(SimpleFreeList *fl_ptr);
//Tell rename map to get a free physical register for a given
//architected register. Not sure it should have a return value,
//but perhaps it should have some sort of fault in case there are
//no free registers.
RenameInfo rename(RegIndex arch_reg);
PhysRegIndex lookup(RegIndex phys_reg);
/**
* Marks the given register as ready, meaning that its value has been
* calculated and written to the register file.
* @param ready_reg The index of the physical register that is now ready.
*/
void setEntry(RegIndex arch_reg, PhysRegIndex renamed_reg);
int numFreeEntries();
private:
/** Rename Map ID */
int id;
/** Number of logical integer registers. */
int numLogicalIntRegs;
/** Number of physical integer registers. */
int numPhysicalIntRegs;
/** Number of logical floating point registers. */
int numLogicalFloatRegs;
/** Number of physical floating point registers. */
int numPhysicalFloatRegs;
/** Number of miscellaneous registers. */
int numMiscRegs;
/** Number of logical integer + float registers. */
int numLogicalRegs;
/** Number of physical integer + float registers. */
int numPhysicalRegs;
/** The integer zero register. This implementation assumes it is always
* zero and never can be anything else.
*/
RegIndex intZeroReg;
/** The floating point zero register. This implementation assumes it is
* always zero and never can be anything else.
*/
RegIndex floatZeroReg;
class RenameEntry
{
public:
PhysRegIndex physical_reg;
bool valid;
RenameEntry()
: physical_reg(0), valid(false)
{ }
};
private:
/** Integer rename map. */
std::vector<RenameEntry> intRenameMap;
/** Floating point rename map. */
std::vector<RenameEntry> floatRenameMap;
private:
/** Free list interface. */
SimpleFreeList *freeList;
};
#endif //__CPU_O3_RENAME_MAP_HH__