1/*
2 * Copyright (c) 2018 Metempsy Technology Consulting
3 * All rights reserved.
4 *
5 * Copyright (c) 2006 INRIA (Institut National de Recherche en
6 * Informatique et en Automatique  / French National Research Institute
7 * for Computer Science and Applied Mathematics)
8 *
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions are
13 * met: redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer;
15 * redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution;
18 * neither the name of the copyright holders nor the names of its
19 * contributors may be used to endorse or promote products derived from
20 * this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
25 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
26 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
28 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
32 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 *
34 * Author: André Seznec, Pau Cabre, Javier Bueno
35 *
36 */
37
38/*
39 * 64KB TAGE-SC-L branch predictor (devised by Andre Seznec)
40 *
41 * Most of the code in this file has been adapted from cbp64KB/predictor.h in
42 * http://www.jilp.org/cbp2016/code/AndreSeznecLimited.tar.gz
43 */
44
45#ifndef __CPU_PRED_TAGE_SC_L_64KB
46#define __CPU_PRED_TAGE_SC_L_64KB
47
48#include "cpu/pred/tage_sc_l.hh"
49#include "params/TAGE_SC_L_64KB.hh"
50#include "params/TAGE_SC_L_64KB_StatisticalCorrector.hh"
51#include "params/TAGE_SC_L_TAGE_64KB.hh"
52
53class TAGE_SC_L_TAGE_64KB : public TAGE_SC_L_TAGE {
54    public:
55    TAGE_SC_L_TAGE_64KB(const TAGE_SC_L_TAGE_64KBParams *p) : TAGE_SC_L_TAGE(p)
56    {}
57
58    int gindex_ext(int index, int bank) const override;
59
60    uint16_t gtag(ThreadID tid, Addr pc, int bank) const override;
61
62    void handleAllocAndUReset(
63        bool alloc, bool taken, TAGEBase::BranchInfo* bi, int nrand) override;
64
65    void handleTAGEUpdate(
66        Addr branch_pc, bool taken, TAGEBase::BranchInfo* bi) override;
67};
68
69class TAGE_SC_L_64KB_StatisticalCorrector : public StatisticalCorrector
70{
71    const unsigned numEntriesSecondLocalHistories;
72    const unsigned numEntriesThirdLocalHistories;
73
74    // global branch history variation GEHL
75    const unsigned pnb;
76    const unsigned logPnb;
77    std::vector<int> pm;
78    std::vector<int8_t> * pgehl;
79    std::vector<int8_t> wp;
80
81    // Second local history GEHL
82    const unsigned snb;
83    const unsigned logSnb;
84    std::vector<int> sm;
85    std::vector<int8_t> * sgehl;
86    std::vector<int8_t> ws;
87
88    // Third local history GEHL
89    const unsigned tnb;
90    const unsigned logTnb;
91    std::vector<int> tm;
92    std::vector<int8_t> * tgehl;
93    std::vector<int8_t> wt;
94
95    // Second IMLI GEHL
96    const unsigned imnb;
97    const unsigned logImnb;
98    std::vector<int> imm;
99    std::vector<int8_t> * imgehl;
100    std::vector<int8_t> wim;
101
102    struct SC_64KB_ThreadHistory : public SCThreadHistory
103    {
104        std::vector<int64_t> imHist;
105    };
106
107    SCThreadHistory *makeThreadHistory() override;
108
109  public:
110    TAGE_SC_L_64KB_StatisticalCorrector(
111        TAGE_SC_L_64KB_StatisticalCorrectorParams *p);
112
113    unsigned getIndBiasBank(Addr branch_pc, BranchInfo* bi, int hitBank,
114        int altBank) const override;
115
116    int gPredictions(ThreadID tid, Addr branch_pc, BranchInfo* bi,
117                     int & lsum, int64_t phist) override;
118
119    int gIndexLogsSubstr(int nbr, int i) override;
120
121    void scHistoryUpdate(Addr branch_pc, const StaticInstPtr &inst, bool taken,
122                         BranchInfo * tage_bi, Addr corrTarget) override;
123
124    void gUpdates(ThreadID tid, Addr pc, bool taken, BranchInfo* bi,
125            int64_t phist) override;
126};
127
128class TAGE_SC_L_64KB : public TAGE_SC_L
129{
130  public:
131    TAGE_SC_L_64KB(const TAGE_SC_L_64KBParams *params);
132};
133
134#endif // __CPU_PRED_TAGE_SC_L_64KB
135
136