diff options
| -rw-r--r-- | configs/common/O3_ARM_v7a.py | 5 | ||||
| -rw-r--r-- | src/cpu/pred/BranchPredictor.py | 2 | ||||
| -rw-r--r-- | src/cpu/pred/tournament.cc | 21 |
3 files changed, 16 insertions, 12 deletions
diff --git a/configs/common/O3_ARM_v7a.py b/configs/common/O3_ARM_v7a.py index c85ba2c6c..f5cd3bbc8 100644 --- a/configs/common/O3_ARM_v7a.py +++ b/configs/common/O3_ARM_v7a.py @@ -90,12 +90,11 @@ class O3_ARM_v7a_FUP(FUPool): # Tournament Branch Predictor class O3_ARM_v7a_BP(BranchPredictor): predType = "tournament" + localPredictorSize = 2048 localCtrBits = 2 - localHistoryTableSize = 64 - localHistoryBits = 6 + localHistoryTableSize = 1024 globalPredictorSize = 8192 globalCtrBits = 2 - globalHistoryBits = 13 choicePredictorSize = 8192 choiceCtrBits = 2 BTBEntries = 2048 diff --git a/src/cpu/pred/BranchPredictor.py b/src/cpu/pred/BranchPredictor.py index 21001b360..07fc840b8 100644 --- a/src/cpu/pred/BranchPredictor.py +++ b/src/cpu/pred/BranchPredictor.py @@ -40,10 +40,8 @@ class BranchPredictor(SimObject): localPredictorSize = Param.Unsigned(2048, "Size of local predictor") localCtrBits = Param.Unsigned(2, "Bits per counter") localHistoryTableSize = Param.Unsigned(2048, "Size of local history table") - localHistoryBits = Param.Unsigned(11, "Bits for the local history") globalPredictorSize = Param.Unsigned(8192, "Size of global predictor") globalCtrBits = Param.Unsigned(2, "Bits per counter") - globalHistoryBits = Param.Unsigned(13, "Bits of history") choicePredictorSize = Param.Unsigned(8192, "Size of choice predictor") choiceCtrBits = Param.Unsigned(2, "Bits of choice counters") diff --git a/src/cpu/pred/tournament.cc b/src/cpu/pred/tournament.cc index 52a05960f..e471d08f5 100644 --- a/src/cpu/pred/tournament.cc +++ b/src/cpu/pred/tournament.cc @@ -46,17 +46,28 @@ TournamentBP::TournamentBP(const Params *params) : BPredUnit(params), + localPredictorSize(params->localPredictorSize), localCtrBits(params->localCtrBits), localHistoryTableSize(params->localHistoryTableSize), - localHistoryBits(params->localHistoryBits), + localHistoryBits(ceilLog2(params->localPredictorSize)), globalPredictorSize(params->globalPredictorSize), globalCtrBits(params->globalCtrBits), - globalHistoryBits(params->globalHistoryBits), + globalHistoryBits( + ceilLog2(params->globalPredictorSize) > + ceilLog2(params->choicePredictorSize) ? + ceilLog2(params->globalPredictorSize) : + ceilLog2(params->choicePredictorSize)), choicePredictorSize(params->choicePredictorSize), choiceCtrBits(params->choiceCtrBits), instShiftAmt(params->instShiftAmt) { - localPredictorSize = ULL(1) << localHistoryBits; + if (!isPowerOf2(localPredictorSize)) { + fatal("Invalid local predictor size!\n"); + } + + if (!isPowerOf2(globalPredictorSize)) { + fatal("Invalid global predictor size!\n"); + } //Set up the array of counters for the local predictor localCtrs.resize(localPredictorSize); @@ -76,10 +87,6 @@ TournamentBP::TournamentBP(const Params *params) for (int i = 0; i < localHistoryTableSize; ++i) localHistoryTable[i] = 0; - if (!isPowerOf2(globalPredictorSize)) { - fatal("Invalid global predictor size!\n"); - } - //Setup the array of counters for the global predictor globalCtrs.resize(globalPredictorSize); |