btb.cc

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#include "cpu/pred/btb.hh"
 
namespace gem5
{
 
namespace branch_prediction
{
 
BranchTargetBuffer::BranchTargetBuffer(const Params &params)
    : ClockedObject(params),
      numThreads(params.numThreads),
      stats(this)
{
}
 
BranchTargetBuffer::BranchTargetBufferStats::BranchTargetBufferStats(
                                                statistics::Group *parent)
    : statistics::Group(parent),
      ADD_STAT(lookups, statistics::units::Count::get(),
               "Number of BTB lookups"),
      ADD_STAT(misses, statistics::units::Count::get(),
               "Number of BTB misses"),
      ADD_STAT(updates, statistics::units::Count::get(),
               "Number of BTB updates"),
      ADD_STAT(mispredict, statistics::units::Count::get(),
               "Number of BTB mispredictions. "
               "No target found or target wrong."),
      ADD_STAT(evictions, statistics::units::Count::get(),
               "Number of BTB evictions")
{
    using namespace statistics;
    lookups
        .init(enums::Num_BranchType)
        .flags(total | pdf);
 
    misses
        .init(enums::Num_BranchType)
        .flags(total | pdf);
 
    updates
        .init(enums::Num_BranchType)
        .flags(total | pdf);
 
    mispredict
        .init(enums::Num_BranchType)
        .flags(total | pdf);
 
    evictions.flags(nozero);
 
    for (int i = 0; i < enums::Num_BranchType; i++) {
        lookups.subname(i, enums::BranchTypeStrings[i]);
        misses.subname(i, enums::BranchTypeStrings[i]);
        updates.subname(i, enums::BranchTypeStrings[i]);
        mispredict.subname(i, enums::BranchTypeStrings[i]);
    }
}
 
} // namespace branch_prediction
} // namespace gem5