base_set_assoc.cc

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#include "mem/cache/tags/base_set_assoc.hh"
 
#include <string>
 
#include "base/intmath.hh"
 
namespace gem5
{
 
BaseSetAssoc::BaseSetAssoc(const Params &p)
    :BaseTags(p), allocAssoc(p.assoc), blks(p.size / p.block_size),
     sequentialAccess(p.sequential_access),
     replacementPolicy(p.replacement_policy)
{
    // There must be a indexing policy
    fatal_if(!p.indexing_policy, "An indexing policy is required");
 
    // Check parameters
    if (blkSize < 4 || !isPowerOf2(blkSize)) {
        fatal("Block size must be at least 4 and a power of 2");
    }
}
 
void
BaseSetAssoc::tagsInit()
{
    // Initialize all blocks
    for (unsigned blk_index = 0; blk_index < numBlocks; blk_index++) {
        // Locate next cache block
        CacheBlk* blk = &blks[blk_index];
 
        // Link block to indexing policy
        indexingPolicy->setEntry(blk, blk_index);
 
        // Associate a data chunk to the block
        blk->data = &dataBlks[blkSize*blk_index];
 
        // Associate a replacement data entry to the block
        blk->replacementData = replacementPolicy->instantiateEntry();
    }
}
 
void
BaseSetAssoc::invalidate(CacheBlk *blk)
{
    BaseTags::invalidate(blk);
 
    // Decrease the number of tags in use
    stats.tagsInUse--;
 
    // Invalidate replacement data
    replacementPolicy->invalidate(blk->replacementData);
}
 
void
BaseSetAssoc::moveBlock(CacheBlk *src_blk, CacheBlk *dest_blk)
{
    BaseTags::moveBlock(src_blk, dest_blk);
 
    // Since the blocks were using different replacement data pointers,
    // we must touch the replacement data of the new entry, and invalidate
    // the one that is being moved.
    replacementPolicy->invalidate(src_blk->replacementData);
    replacementPolicy->reset(dest_blk->replacementData);
}
 
} // namespace gem5