2922f763e1
The systemc dir was not included in this fix.
First it was identified that there were only occurrences
at 0, 1, 2 and 3 levels of indentation (and a single
occurrence of 2 and 3 spaces), using:
grep -nrE --exclude-dir=systemc \
"^ *struct [A-Za-z].* {$" src/
Then the following commands were run to replace:
<indent level>struct X ... {
by:
<indent level>struct X ...
<indent level>{
Level 0:
grep -nrl --exclude-dir=systemc
"^struct [A-Za-z].* {$" src/ | \
xargs sed -Ei \
's/^struct ([A-Za-z].*) \{$/struct \1\n\{/g'
Level 1:
grep -nrl --exclude-dir=systemc \
"^ struct [A-Za-z].* {$" src/ | \
xargs sed -Ei \
's/^ struct ([A-Za-z].*) \{$/ struct \1\n \{/g'
and so on.
Change-Id: I362ef58c86912dabdd272c7debb8d25d587cd455
Signed-off-by: Daniel R. Carvalho <odanrc@yahoo.com.br>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/39017
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
113 lines
4.3 KiB
C++
113 lines
4.3 KiB
C++
/*
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* Copyright (c) 2014 The Regents of The University of Michigan
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are
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* met: redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer;
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* redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution;
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* neither the name of the copyright holders nor the names of its
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* contributors may be used to endorse or promote products derived from
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* this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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/* @file
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* Implementation of a bi-mode branch predictor
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*/
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#ifndef __CPU_PRED_BI_MODE_PRED_HH__
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#define __CPU_PRED_BI_MODE_PRED_HH__
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#include "base/sat_counter.hh"
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#include "cpu/pred/bpred_unit.hh"
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#include "params/BiModeBP.hh"
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/**
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* Implements a bi-mode branch predictor. The bi-mode predictor is a two-level
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* branch predictor that has three seprate history arrays: a taken array, a
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* not-taken array, and a choice array. The taken/not-taken arrays are indexed
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* by a hash of the PC and the global history. The choice array is indexed by
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* the PC only. Because the taken/not-taken arrays use the same index, they must
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* be the same size.
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*
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* The bi-mode branch predictor aims to eliminate the destructive aliasing that
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* occurs when two branches of opposite biases share the same global history
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* pattern. By separating the predictors into taken/not-taken arrays, and using
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* the branch's PC to choose between the two, destructive aliasing is reduced.
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*/
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class BiModeBP : public BPredUnit
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{
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public:
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BiModeBP(const BiModeBPParams ¶ms);
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void uncondBranch(ThreadID tid, Addr pc, void * &bp_history);
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void squash(ThreadID tid, void *bp_history);
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bool lookup(ThreadID tid, Addr branch_addr, void * &bp_history);
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void btbUpdate(ThreadID tid, Addr branch_addr, void * &bp_history);
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void update(ThreadID tid, Addr branch_addr, bool taken, void *bp_history,
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bool squashed, const StaticInstPtr & inst, Addr corrTarget);
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private:
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void updateGlobalHistReg(ThreadID tid, bool taken);
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struct BPHistory
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{
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unsigned globalHistoryReg;
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// was the taken array's prediction used?
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// true: takenPred used
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// false: notPred used
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bool takenUsed;
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// prediction of the taken array
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// true: predict taken
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// false: predict not-taken
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bool takenPred;
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// prediction of the not-taken array
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// true: predict taken
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// false: predict not-taken
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bool notTakenPred;
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// the final taken/not-taken prediction
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// true: predict taken
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// false: predict not-taken
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bool finalPred;
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};
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std::vector<unsigned> globalHistoryReg;
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unsigned globalHistoryBits;
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unsigned historyRegisterMask;
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unsigned choicePredictorSize;
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unsigned choiceCtrBits;
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unsigned choiceHistoryMask;
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unsigned globalPredictorSize;
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unsigned globalCtrBits;
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unsigned globalHistoryMask;
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// choice predictors
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std::vector<SatCounter8> choiceCounters;
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// taken direction predictors
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std::vector<SatCounter8> takenCounters;
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// not-taken direction predictors
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std::vector<SatCounter8> notTakenCounters;
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unsigned choiceThreshold;
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unsigned takenThreshold;
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unsigned notTakenThreshold;
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};
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#endif // __CPU_PRED_BI_MODE_PRED_HH__
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