From 34ad1123ee5927e3b1503f07649620a533d3eab9 Mon Sep 17 00:00:00 2001 From: Dibakar Gope Date: Mon, 13 Apr 2015 17:33:57 -0500 Subject: cpu: re-organizes the branch predictor structure. Committed by: Nilay Vaish --- src/cpu/pred/BranchPredictor.py | 42 +++++++++++++++++++++++++++++++++-------- 1 file changed, 34 insertions(+), 8 deletions(-) (limited to 'src/cpu/pred/BranchPredictor.py') diff --git a/src/cpu/pred/BranchPredictor.py b/src/cpu/pred/BranchPredictor.py index 1bdc71d4d..5c52fb65e 100644 --- a/src/cpu/pred/BranchPredictor.py +++ b/src/cpu/pred/BranchPredictor.py @@ -1,4 +1,5 @@ # Copyright (c) 2012 Mark D. Hill and David A. Wood +# Copyright (c) 2015 The University of Wisconsin # All rights reserved. # # Redistribution and use in source and binary forms, with or without @@ -24,7 +25,7 @@ # (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: Nilay Vaish +# Authors: Nilay Vaish and Dibakar Gope from m5.SimObject import SimObject from m5.params import * @@ -33,20 +34,45 @@ class BranchPredictor(SimObject): type = 'BranchPredictor' cxx_class = 'BPredUnit' cxx_header = "cpu/pred/bpred_unit.hh" + abstract = True numThreads = Param.Unsigned(1, "Number of threads") - predType = Param.String("tournament", - "Branch predictor type ('local', 'tournament', 'bi-mode')") + BTBEntries = Param.Unsigned(4096, "Number of BTB entries") + BTBTagSize = Param.Unsigned(16, "Size of the BTB tags, in bits") + RASSize = Param.Unsigned(16, "RAS size") + instShiftAmt = Param.Unsigned(2, "Number of bits to shift instructions by") + + +class LocalBP(BranchPredictor): + type = 'LocalBP' + cxx_class = 'LocalBP' + cxx_header = "cpu/pred/2bit_local.hh" + + localPredictorSize = Param.Unsigned(2048, "Size of local predictor") + localCtrBits = Param.Unsigned(2, "Bits per counter") + + +class TournamentBP(BranchPredictor): + type = 'TournamentBP' + cxx_class = 'TournamentBP' + cxx_header = "cpu/pred/tournament.hh" + localPredictorSize = Param.Unsigned(2048, "Size of local predictor") localCtrBits = Param.Unsigned(2, "Bits per counter") - localHistoryTableSize = Param.Unsigned(2048, "Size of local history table") + localHistoryTableSize = Param.Unsigned(2048, "size of local history table") globalPredictorSize = Param.Unsigned(8192, "Size of global predictor") globalCtrBits = Param.Unsigned(2, "Bits per counter") choicePredictorSize = Param.Unsigned(8192, "Size of choice predictor") choiceCtrBits = Param.Unsigned(2, "Bits of choice counters") - BTBEntries = Param.Unsigned(4096, "Number of BTB entries") - BTBTagSize = Param.Unsigned(16, "Size of the BTB tags, in bits") - RASSize = Param.Unsigned(16, "RAS size") - instShiftAmt = Param.Unsigned(2, "Number of bits to shift instructions by") +class BiModeBP(BranchPredictor): + type = 'BiModeBP' + cxx_class = 'BiModeBP' + cxx_header = "cpu/pred/bi_mode.hh" + + globalPredictorSize = Param.Unsigned(8192, "Size of global predictor") + globalCtrBits = Param.Unsigned(2, "Bits per counter") + choicePredictorSize = Param.Unsigned(8192, "Size of choice predictor") + choiceCtrBits = Param.Unsigned(2, "Bits of choice counters") + -- cgit v1.2.3