gem5  v20.1.0.0
base_set_assoc.cc
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40 
47 
48 #include <string>
49 
50 #include "base/intmath.hh"
51 
53  :BaseTags(p), allocAssoc(p->assoc), blks(p->size / p->block_size),
54  sequentialAccess(p->sequential_access),
55  replacementPolicy(p->replacement_policy)
56 {
57  // Check parameters
58  if (blkSize < 4 || !isPowerOf2(blkSize)) {
59  fatal("Block size must be at least 4 and a power of 2");
60  }
61 }
62 
63 void
65 {
66  // Initialize all blocks
67  for (unsigned blk_index = 0; blk_index < numBlocks; blk_index++) {
68  // Locate next cache block
69  CacheBlk* blk = &blks[blk_index];
70 
71  // Link block to indexing policy
72  indexingPolicy->setEntry(blk, blk_index);
73 
74  // Associate a data chunk to the block
75  blk->data = &dataBlks[blkSize*blk_index];
76 
77  // Associate a replacement data entry to the block
79  }
80 }
81 
82 void
84 {
86 
87  // Decrease the number of tags in use
88  stats.tagsInUse--;
89 
90  // Invalidate replacement data
92 }
93 
95 BaseSetAssocParams::create()
96 {
97  // There must be a indexing policy
98  fatal_if(!indexing_policy, "An indexing policy is required");
99 
100  return new BaseSetAssoc(this);
101 }
fatal
#define fatal(...)
This implements a cprintf based fatal() function.
Definition: logging.hh:183
BaseTags::dataBlks
std::unique_ptr< uint8_t[]> dataBlks
The data blocks, 1 per cache block.
Definition: base.hh:100
BaseTags::numBlocks
const unsigned numBlocks
the number of blocks in the cache
Definition: base.hh:97
BaseReplacementPolicy::invalidate
virtual void invalidate(const std::shared_ptr< ReplacementData > &replacement_data) const =0
Invalidate replacement data to set it as the next probable victim.
BaseSetAssoc::BaseSetAssoc
BaseSetAssoc(const Params *p)
Construct and initialize this tag store.
Definition: base_set_assoc.cc:52
BaseReplacementPolicy::instantiateEntry
virtual std::shared_ptr< ReplacementData > instantiateEntry()=0
Instantiate a replacement data entry.
BaseSetAssoc::tagsInit
void tagsInit() override
Initialize blocks as CacheBlk instances.
Definition: base_set_assoc.cc:64
BaseTags::invalidate
virtual void invalidate(CacheBlk *blk)
This function updates the tags when a block is invalidated.
Definition: base.hh:251
BaseTags::BaseTagStats::tagsInUse
Stats::Average tagsInUse
Per cycle average of the number of tags that hold valid data.
Definition: base.hh:115
BaseSetAssoc::invalidate
void invalidate(CacheBlk *blk) override
This function updates the tags when a block is invalidated.
Definition: base_set_assoc.cc:83
BaseSetAssoc
A basic cache tag store.
Definition: base_set_assoc.hh:72
BaseTags
A common base class of Cache tagstore objects.
Definition: base.hh:70
BaseTags::Params
BaseTagsParams Params
Definition: base.hh:158
BaseIndexingPolicy::setEntry
void setEntry(ReplaceableEntry *entry, const uint64_t index)
Associate a pointer to an entry to its physical counterpart.
Definition: base.cc:78
BaseTags::blkSize
const unsigned blkSize
The block size of the cache.
Definition: base.hh:74
BaseTags::indexingPolicy
BaseIndexingPolicy * indexingPolicy
Indexing policy.
Definition: base.hh:86
BaseTags::stats
BaseTags::BaseTagStats stats
CacheBlk::data
uint8_t * data
Contains a copy of the data in this block for easy access.
Definition: cache_blk.hh:99
CacheBlk
A Basic Cache block.
Definition: cache_blk.hh:84
ReplaceableEntry::replacementData
std::shared_ptr< ReplacementData > replacementData
Replacement data associated to this entry.
Definition: replaceable_entry.hh:74
base_set_assoc.hh
MipsISA::p
Bitfield< 0 > p
Definition: pra_constants.hh:323
intmath.hh
fatal_if
#define fatal_if(cond,...)
Conditional fatal macro that checks the supplied condition and only causes a fatal error if the condi...
Definition: logging.hh:219
isPowerOf2
bool isPowerOf2(const T &n)
Definition: intmath.hh:102
BaseSetAssoc::blks
std::vector< CacheBlk > blks
The cache blocks.
Definition: base_set_assoc.hh:79
BaseSetAssoc::replacementPolicy
BaseReplacementPolicy * replacementPolicy
Replacement policy.
Definition: base_set_assoc.hh:85

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