BranchPredictor.py revision 10244:d2deb51a4abf 
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
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7# notice, this list of conditions and the following disclaimer;
8# redistributions in binary form must reproduce the above copyright
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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
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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', 'bi-mode')")
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    globalPredictorSize = Param.Unsigned(8192, "Size of global predictor")
44    globalCtrBits = Param.Unsigned(2, "Bits per counter")
45    choicePredictorSize = Param.Unsigned(8192, "Size of choice predictor")
46    choiceCtrBits = Param.Unsigned(2, "Bits of choice counters")
47
48    BTBEntries = Param.Unsigned(4096, "Number of BTB entries")
49    BTBTagSize = Param.Unsigned(16, "Size of the BTB tags, in bits")
50
51    RASSize = Param.Unsigned(16, "RAS size")
52    instShiftAmt = Param.Unsigned(2, "Number of bits to shift instructions by")
53