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/*
* Copyright (c) 2011, 2016-2017 ARM Limited
* Copyright (c) 2013 Advanced Micro Devices, Inc.
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
* Copyright (c) 2004-2006 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.
*/
#ifndef __CPU_O3_COMM_HH__
#define __CPU_O3_COMM_HH__
#include <vector>
#include "arch/generic/pcstate.hh"
#include "base/types.hh"
#include "cpu/inst_seq.hh"
#include "cpu/o3/dyn_inst_ptr.hh"
#include "cpu/o3/limits.hh"
#include "sim/faults.hh"
namespace gem5
{
namespace o3
{
/** Struct that defines the information passed from fetch to decode. */
struct FetchStruct
{
int size;
DynInstPtr insts[MaxWidth];
Fault fetchFault;
InstSeqNum fetchFaultSN;
bool clearFetchFault;
};
/** Struct that defines the information passed from decode to rename. */
struct DecodeStruct
{
int size;
DynInstPtr insts[MaxWidth];
};
/** Struct that defines the information passed from rename to IEW. */
struct RenameStruct
{
int size;
DynInstPtr insts[MaxWidth];
};
/** Struct that defines the information passed from IEW to commit. */
struct IEWStruct
{
int size;
DynInstPtr insts[MaxWidth];
DynInstPtr mispredictInst[MaxThreads];
Addr mispredPC[MaxThreads];
InstSeqNum squashedSeqNum[MaxThreads];
std::unique_ptr<PCStateBase> pc[MaxThreads];
bool squash[MaxThreads];
bool branchMispredict[MaxThreads];
bool branchTaken[MaxThreads];
bool includeSquashInst[MaxThreads];
};
struct IssueStruct
{
int size;
DynInstPtr insts[MaxWidth];
};
/** Struct that defines all backwards communication. */
struct TimeStruct
{
struct DecodeComm
{
std::unique_ptr<PCStateBase> nextPC;
DynInstPtr mispredictInst;
DynInstPtr squashInst;
InstSeqNum doneSeqNum;
Addr mispredPC;
uint64_t branchAddr;
unsigned branchCount;
bool squash;
bool predIncorrect;
bool branchMispredict;
bool branchTaken;
};
DecodeComm decodeInfo[MaxThreads];
struct RenameComm {};
RenameComm renameInfo[MaxThreads];
struct IewComm
{
// Also eventually include skid buffer space.
unsigned freeIQEntries;
unsigned freeLQEntries;
unsigned freeSQEntries;
unsigned dispatchedToLQ;
unsigned dispatchedToSQ;
unsigned iqCount;
unsigned ldstqCount;
unsigned dispatched;
bool usedIQ;
bool usedLSQ;
};
IewComm iewInfo[MaxThreads];
struct CommitComm
{
/////////////////////////////////////////////////////////////////////
// This code has been re-structured for better packing of variables
// instead of by stage which is the more logical way to arrange the
// data.
// F = Fetch
// D = Decode
// I = IEW
// R = Rename
// As such each member is annotated with who consumes it
// e.g. bool variable name // *F,R for Fetch and Rename
/////////////////////////////////////////////////////////////////////
/// The pc of the next instruction to execute. This is the next
/// instruction for a branch mispredict, but the same instruction for
/// order violation and the like
std::unique_ptr<PCStateBase> pc; // *F
/// Provide fetch the instruction that mispredicted, if this
/// pointer is not-null a misprediction occured
DynInstPtr mispredictInst; // *F
/// Instruction that caused the a non-mispredict squash
DynInstPtr squashInst; // *F
/// Hack for now to send back a strictly ordered access to the
/// IEW stage.
DynInstPtr strictlyOrderedLoad; // *I
/// Communication specifically to the IQ to tell the IQ that it can
/// schedule a non-speculative instruction.
InstSeqNum nonSpecSeqNum; // *I
/// Represents the instruction that has either been retired or
/// squashed. Similar to having a single bus that broadcasts the
/// retired or squashed sequence number.
InstSeqNum doneSeqNum; // *F, I
/// Tell Rename how many free entries it has in the ROB
unsigned freeROBEntries; // *R
bool squash; // *F, D, R, I
bool robSquashing; // *F, D, R, I
/// Rename should re-read number of free rob entries
bool usedROB; // *R
/// Notify Rename that the ROB is empty
bool emptyROB; // *R
/// Was the branch taken or not
bool branchTaken; // *F
/// If an interrupt is pending and fetch should stall
bool interruptPending; // *F
/// If the interrupt ended up being cleared before being handled
bool clearInterrupt; // *F
/// Hack for now to send back an strictly ordered access to
/// the IEW stage.
bool strictlyOrdered; // *I
};
CommitComm commitInfo[MaxThreads];
bool decodeBlock[MaxThreads];
bool decodeUnblock[MaxThreads];
bool renameBlock[MaxThreads];
bool renameUnblock[MaxThreads];
bool iewBlock[MaxThreads];
bool iewUnblock[MaxThreads];
};
} // namespace o3
} // namespace gem5
#endif //__CPU_O3_COMM_HH__