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+/*
+ * Copyright (c) 2004-2005 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_BETA_CPU_TOURNAMENT_PRED_HH__
+#define __CPU_BETA_CPU_TOURNAMENT_PRED_HH__
+
+// For Addr type.
+#include "arch/alpha/isa_traits.hh"
+#include "cpu/o3/sat_counter.hh"
+
+class TournamentBP
+{
+ public:
+ /**
+ * Default branch predictor constructor.
+ */
+ TournamentBP(unsigned local_predictor_size,
+ unsigned local_ctr_bits,
+ unsigned local_history_table_size,
+ unsigned local_history_bits,
+ unsigned global_predictor_size,
+ unsigned global_history_bits,
+ unsigned global_ctr_bits,
+ unsigned choice_predictor_size,
+ unsigned choice_ctr_bits,
+ unsigned instShiftAmt);
+
+ /**
+ * Looks up the given address in the branch predictor and returns
+ * a true/false value as to whether it is taken.
+ * @param branch_addr The address of the branch to look up.
+ * @return Whether or not the branch is taken.
+ */
+ bool lookup(Addr &branch_addr);
+
+ /**
+ * Updates the branch predictor with the actual result of a branch.
+ * @param branch_addr The address of the branch to update.
+ * @param taken Whether or not the branch was taken.
+ */
+ void update(Addr &branch_addr, unsigned global_history, bool taken);
+
+ inline unsigned readGlobalHist() { return globalHistory; }
+
+ private:
+
+ inline bool getPrediction(uint8_t &count);
+
+ inline unsigned calcLocHistIdx(Addr &branch_addr);
+
+ inline void updateHistoriesTaken(unsigned local_history_idx);
+
+ inline void updateHistoriesNotTaken(unsigned local_history_idx);
+
+ /** Local counters. */
+ SatCounter *localCtrs;
+
+ /** Size of the local predictor. */
+ unsigned localPredictorSize;
+
+ /** Number of bits of the local predictor's counters. */
+ unsigned localCtrBits;
+
+ /** Array of local history table entries. */
+ unsigned *localHistoryTable;
+
+ /** Size of the local history table. */
+ unsigned localHistoryTableSize;
+
+ /** Number of bits for each entry of the local history table.
+ * @todo Doesn't this come from the size of the local predictor?
+ */
+ unsigned localHistoryBits;
+
+ /** Mask to get the proper local history. */
+ unsigned localHistoryMask;
+
+
+ /** Array of counters that make up the global predictor. */
+ SatCounter *globalCtrs;
+
+ /** Size of the global predictor. */
+ unsigned globalPredictorSize;
+
+ /** Number of bits of the global predictor's counters. */
+ unsigned globalCtrBits;
+
+ /** Global history register. */
+ unsigned globalHistory;
+
+ /** Number of bits for the global history. */
+ unsigned globalHistoryBits;
+
+ /** Mask to get the proper global history. */
+ unsigned globalHistoryMask;
+
+
+ /** Array of counters that make up the choice predictor. */
+ SatCounter *choiceCtrs;
+
+ /** Size of the choice predictor (identical to the global predictor). */
+ unsigned choicePredictorSize;
+
+ /** Number of bits of the choice predictor's counters. */
+ unsigned choiceCtrBits;
+
+ /** Number of bits to shift the instruction over to get rid of the word
+ * offset.
+ */
+ unsigned instShiftAmt;
+
+ /** Threshold for the counter value; above the threshold is taken,
+ * equal to or below the threshold is not taken.
+ */
+ unsigned threshold;
+};
+
+#endif // __CPU_BETA_CPU_TOURNAMENT_PRED_HH__