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base_set_assoc.cc
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40  * Authors: Erik Hallnor
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42 
49 
50 #include <string>
51 
52 #include "base/intmath.hh"
53 
55  :BaseTags(p), allocAssoc(p->assoc), blks(p->size / p->block_size),
56  sequentialAccess(p->sequential_access),
57  replacementPolicy(p->replacement_policy)
58 {
59  // Check parameters
60  if (blkSize < 4 || !isPowerOf2(blkSize)) {
61  fatal("Block size must be at least 4 and a power of 2");
62  }
63 }
64 
65 void
67 {
68  // Initialize all blocks
69  for (unsigned blk_index = 0; blk_index < numBlocks; blk_index++) {
70  // Locate next cache block
71  CacheBlk* blk = &blks[blk_index];
72 
73  // Link block to indexing policy
74  indexingPolicy->setEntry(blk, blk_index);
75 
76  // Associate a data chunk to the block
77  blk->data = &dataBlks[blkSize*blk_index];
78 
79  // Associate a replacement data entry to the block
81  }
82 }
83 
84 void
86 {
88 
89  // Decrease the number of tags in use
90  stats.tagsInUse--;
91 
92  // Invalidate replacement data
94 }
95 
97 BaseSetAssocParams::create()
98 {
99  // There must be a indexing policy
100  fatal_if(!indexing_policy, "An indexing policy is required");
101 
102  return new BaseSetAssoc(this);
103 }
#define fatal(...)
This implements a cprintf based fatal() function.
Definition: logging.hh:175
Stats::Average tagsInUse
Per cycle average of the number of tags that hold valid data.
Definition: base.hh:118
std::unique_ptr< uint8_t[]> dataBlks
The data blocks, 1 per cache block.
Definition: base.hh:103
virtual void invalidate(CacheBlk *blk)
This function updates the tags when a block is invalidated.
Definition: base.hh:254
BaseTagsParams Params
Definition: base.hh:161
A Basic Cache block.
Definition: cache_blk.hh:87
BaseSetAssoc(const Params *p)
Construct and initialize this tag store.
A basic cache tag store.
std::shared_ptr< ReplacementData > replacementData
Replacement data associated to this entry.
void tagsInit() override
Initialize blocks as CacheBlk instances.
bool isPowerOf2(const T &n)
Definition: intmath.hh:146
#define fatal_if(cond,...)
Conditional fatal macro that checks the supplied condition and only causes a fatal error if the condi...
Definition: logging.hh:203
const unsigned blkSize
The block size of the cache.
Definition: base.hh:77
void invalidate(CacheBlk *blk) override
This function updates the tags when a block is invalidated.
virtual std::shared_ptr< ReplacementData > instantiateEntry()=0
Instantiate a replacement data entry.
void setEntry(ReplaceableEntry *entry, const uint64_t index)
Associate a pointer to an entry to its physical counterpart.
Definition: base.cc:81
virtual void invalidate(const std::shared_ptr< ReplacementData > &replacement_data) const =0
Invalidate replacement data to set it as the next probable victim.
Declaration of a base set associative tag store.
BaseTags::BaseTagStats stats
std::vector< CacheBlk > blks
The cache blocks.
BaseReplacementPolicy * replacementPolicy
Replacement policy.
BaseIndexingPolicy * indexingPolicy
Indexing policy.
Definition: base.hh:89
const unsigned numBlocks
the number of blocks in the cache
Definition: base.hh:100
Bitfield< 0 > p
A common base class of Cache tagstore objects.
Definition: base.hh:73
uint8_t * data
Contains a copy of the data in this block for easy access.
Definition: cache_blk.hh:102

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