BranchPredictor.py revision 9480:d059f8a95a42
1# Copyright (c) 2012 Mark D. Hill and David A. Wood 2# All rights reserved. 3# 4# Redistribution and use in source and binary forms, with or without 5# modification, are permitted provided that the following conditions are 6# met: redistributions of source code must retain the above copyright 7# notice, this list of conditions and the following disclaimer; 8# redistributions in binary form must reproduce the above copyright 9# notice, this list of conditions and the following disclaimer in the 10# documentation and/or other materials provided with the distribution; 11# neither the name of the copyright holders nor the names of its 12# contributors may be used to endorse or promote products derived from 13# this software without specific prior written permission. 14# 15# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 18# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 19# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 21# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26# 27# Authors: Nilay Vaish 28 29from m5.SimObject import SimObject 30from m5.params import * 31 32class BranchPredictor(SimObject): 33 type = 'BranchPredictor' 34 cxx_class = 'BPredUnit' 35 cxx_header = "cpu/pred/bpred_unit.hh" 36 37 numThreads = Param.Unsigned(1, "Number of threads") 38 predType = Param.String("tournament", 39 "Branch predictor type ('local', 'tournament')") 40 localPredictorSize = Param.Unsigned(2048, "Size of local predictor") 41 localCtrBits = Param.Unsigned(2, "Bits per counter") 42 localHistoryTableSize = Param.Unsigned(2048, "Size of local history table") 43 localHistoryBits = Param.Unsigned(11, "Bits for the local history") 44 globalPredictorSize = Param.Unsigned(8192, "Size of global predictor") 45 globalCtrBits = Param.Unsigned(2, "Bits per counter") 46 globalHistoryBits = Param.Unsigned(13, "Bits of history") 47 choicePredictorSize = Param.Unsigned(8192, "Size of choice predictor") 48 choiceCtrBits = Param.Unsigned(2, "Bits of choice counters") 49 50 BTBEntries = Param.Unsigned(4096, "Number of BTB entries") 51 BTBTagSize = Param.Unsigned(16, "Size of the BTB tags, in bits") 52 53 RASSize = Param.Unsigned(16, "RAS size") 54 instShiftAmt = Param.Unsigned(2, "Number of bits to shift instructions by") 55