gem5  v20.1.0.0
skewed_associative.hh
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28 
34 #ifndef __MEM_CACHE_INDEXING_POLICIES_SKEWED_ASSOCIATIVE_HH__
35 #define __MEM_CACHE_INDEXING_POLICIES_SKEWED_ASSOCIATIVE_HH__
36 
37 #include <vector>
38 
40 #include "params/SkewedAssociative.hh"
41 
42 class ReplaceableEntry;
43 
70 {
71  private:
78  const int NUM_SKEWING_FUNCTIONS = 8;
79 
83  const int msbShift;
84 
97  Addr hash(const Addr addr) const;
98 
106  Addr dehash(const Addr addr) const;
107 
116  Addr skew(const Addr addr, const uint32_t way) const;
117 
127  Addr deskew(const Addr addr, const uint32_t way) const;
128 
136  uint32_t extractSet(const Addr addr, const uint32_t way) const;
137 
138  public:
140  typedef SkewedAssociativeParams Params;
141 
145  SkewedAssociative(const Params *p);
146 
151 
161  override;
162 
171  Addr regenerateAddr(const Addr tag, const ReplaceableEntry* entry) const
172  override;
173 };
174 
175 #endif //__MEM_CACHE_INDEXING_POLICIES_SKEWED_ASSOCIATIVE_HH__
ReplaceableEntry
A replaceable entry is a basic entry in a 2d table-like structure that needs to have replacement func...
Definition: replaceable_entry.hh:53
SkewedAssociative::NUM_SKEWING_FUNCTIONS
const int NUM_SKEWING_FUNCTIONS
The number of skewing functions implemented.
Definition: skewed_associative.hh:78
SkewedAssociative::hash
Addr hash(const Addr addr) const
The hash function itself.
Definition: skewed_associative.cc:60
SkewedAssociative::regenerateAddr
Addr regenerateAddr(const Addr tag, const ReplaceableEntry *entry) const override
Regenerate an entry's address from its tag and assigned set and way.
Definition: skewed_associative.cc:198
std::vector
STL vector class.
Definition: stl.hh:37
SkewedAssociative::extractSet
uint32_t extractSet(const Addr addr, const uint32_t way) const
Apply a skewing function to calculate address' set given a way.
Definition: skewed_associative.cc:192
base.hh
SkewedAssociative::deskew
Addr deskew(const Addr addr, const uint32_t way) const
Address deskewing function (inverse of the skew function) of the given way.
Definition: skewed_associative.cc:139
SkewedAssociative::getPossibleEntries
std::vector< ReplaceableEntry * > getPossibleEntries(const Addr addr) const override
Find all possible entries for insertion and replacement of an address.
Definition: skewed_associative.cc:207
SkewedAssociative::SkewedAssociative
SkewedAssociative(const Params *p)
Construct and initialize this policy.
Definition: skewed_associative.cc:41
Addr
uint64_t Addr
Address type This will probably be moved somewhere else in the near future.
Definition: types.hh:142
SkewedAssociative::dehash
Addr dehash(const Addr addr) const
Inverse of the hash function.
Definition: skewed_associative.cc:72
SkewedAssociative::Params
SkewedAssociativeParams Params
Convenience typedef.
Definition: skewed_associative.hh:140
SkewedAssociative::msbShift
const int msbShift
The amount to shift a set index to get its MSB.
Definition: skewed_associative.hh:83
BaseIndexingPolicy::Params
BaseIndexingPolicyParams Params
Convenience typedef.
Definition: base.hh:100
SkewedAssociative
A skewed associative indexing policy.
Definition: skewed_associative.hh:69
addr
ip6_addr_t addr
Definition: inet.hh:423
BaseIndexingPolicy
A common base class for indexing table locations.
Definition: base.hh:63
SkewedAssociative::skew
Addr skew(const Addr addr, const uint32_t way) const
Address skewing function selection.
Definition: skewed_associative.cc:87
SkewedAssociative::~SkewedAssociative
~SkewedAssociative()
Destructor.
Definition: skewed_associative.hh:150
MipsISA::p
Bitfield< 0 > p
Definition: pra_constants.hh:323

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