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00032 #include <pch.h>
00033 #include "Sim/Predictor/BPred/BTB.h"
00034 #include "Sim/Foundation/SimPC.h"
00035 #include "Sim/Op/Op.h"
00036
00037 using namespace Onikiri;
00038 using namespace std;
00039
00040 BTB::BTB()
00041 {
00042 m_numEntryBits = 0;
00043 m_numWays = 0;
00044
00045 m_numPred = 0;
00046 m_numTableHit = 0;
00047 m_numTableMiss = 0;
00048 m_numUpdate = 0;
00049 m_numEntries = 0;
00050 m_numHit = 0;
00051 m_numMiss = 0;
00052 m_table = 0;
00053 }
00054
00055 BTB::~BTB()
00056 {
00057 if(m_table != 0)
00058 delete m_table;
00059
00060 m_numEntries = (1 << m_numEntryBits);
00061 ReleaseParam();
00062 }
00063
00064 void BTB::Initialize(InitPhase phase)
00065 {
00066 if(phase == INIT_PRE_CONNECTION){
00067 LoadParam();
00068 m_table =
00069 new SetAssocTableType( HasherType(m_numEntryBits), m_numWays);
00070 }
00071 }
00072
00073
00074 BTBPredict BTB::Predict(const PC& pc)
00075 {
00076 BTBPredict pred = {pc, pc, BT_NON ,false};
00077 ++m_numPred;
00078
00079
00080
00081 pred.hit = m_table->read( pc.address, &pred ) != m_table->end();
00082 if( pred.hit ){
00083 m_numTableHit++;
00084 }
00085 else{
00086 m_numTableMiss++;
00087 }
00088
00089 return pred;
00090 }
00091
00092
00093 void BTB::Update(const OpIterator& op, const BTBPredict& predict)
00094 {
00095 if(!op->GetTaken())
00096 return;
00097
00098
00099 const OpClass& opClass = op->GetOpClass();
00100 bool conditinal = opClass.IsConditionalBranch();
00101 BranchTypeUtility util;
00102
00103
00104 BTBPredict result;
00105 result.predIndexPC = predict.predIndexPC;
00106 result.hit = true;
00107 result.target = op->GetTakenPC();
00108 result.dirPredict = conditinal;
00109 result.type = util.OpClassToBranchType( opClass );
00110
00111 ASSERT( result.type != BT_NON, "BTB must be updated by branch op." );
00112
00113
00114
00115
00116
00117 m_table->write(result.predIndexPC.address, result);
00118 ++m_numUpdate;
00119
00120
00121
00122
00123
00124
00125 if(predict.hit && result.target == predict.target)
00126 ++m_numHit;
00127 else
00128 ++m_numMiss;
00129
00130 }