gem5  v21.1.0.2
base.cc
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41 
48 
49 #include <cstdlib>
50 
51 #include "base/intmath.hh"
52 #include "base/logging.hh"
54 
55 namespace gem5
56 {
57 
59  : SimObject(p), assoc(p.assoc),
60  numSets(p.size / (p.entry_size * assoc)),
61  setShift(floorLog2(p.entry_size)), setMask(numSets - 1), sets(numSets),
62  tagShift(setShift + floorLog2(numSets))
63 {
64  fatal_if(!isPowerOf2(numSets), "# of sets must be non-zero and a power " \
65  "of 2");
66  fatal_if(assoc <= 0, "associativity must be greater than zero");
67 
68  // Make space for the entries
69  for (uint32_t i = 0; i < numSets; ++i) {
70  sets[i].resize(assoc);
71  }
72 }
73 
75 BaseIndexingPolicy::getEntry(const uint32_t set, const uint32_t way) const
76 {
77  return sets[set][way];
78 }
79 
80 void
82 {
83  // Calculate set and way from entry index
84  const std::lldiv_t div_result = std::div((long long)index, assoc);
85  const uint32_t set = div_result.quot;
86  const uint32_t way = div_result.rem;
87 
88  // Sanity check
89  assert(set < numSets);
90 
91  // Assign a free pointer
92  sets[set][way] = entry;
93 
94  // Inform the entry its position
95  entry->setPosition(set, way);
96 }
97 
98 Addr
100 {
101  return (addr >> tagShift);
102 }
103 
104 } // namespace gem5
gem5::BaseIndexingPolicy::Params
BaseIndexingPolicyParams Params
Convenience typedef.
Definition: base.hh:103
gem5::MipsISA::index
Bitfield< 30, 0 > index
Definition: pra_constants.hh:47
gem5::ReplaceableEntry::setPosition
virtual void setPosition(const uint32_t set, const uint32_t way)
Set both the set and way.
Definition: replaceable_entry.hh:93
gem5::BaseIndexingPolicy::BaseIndexingPolicy
BaseIndexingPolicy(const Params &p)
Construct and initialize this policy.
Definition: base.cc:58
gem5::ArmISA::i
Bitfield< 7 > i
Definition: misc_types.hh:66
gem5::isPowerOf2
static constexpr bool isPowerOf2(const T &n)
Definition: intmath.hh:98
base.hh
replaceable_entry.hh
gem5::BaseIndexingPolicy::sets
std::vector< std::vector< ReplaceableEntry * > > sets
The cache sets.
Definition: base.hh:92
gem5::BaseIndexingPolicy::assoc
const unsigned assoc
The associativity.
Definition: base.hh:72
gem5::MipsISA::p
Bitfield< 0 > p
Definition: pra_constants.hh:326
gem5::BaseIndexingPolicy::tagShift
const int tagShift
The amount to shift the address to get the tag.
Definition: base.hh:97
gem5::SimObject
Abstract superclass for simulation objects.
Definition: sim_object.hh:146
gem5::Addr
uint64_t Addr
Address type This will probably be moved somewhere else in the near future.
Definition: types.hh:147
gem5::ReplaceableEntry
A replaceable entry is a basic entry in a 2d table-like structure that needs to have replacement func...
Definition: replaceable_entry.hh:63
gem5::BaseIndexingPolicy::setEntry
void setEntry(ReplaceableEntry *entry, const uint64_t index)
Associate a pointer to an entry to its physical counterpart.
Definition: base.cc:81
gem5::floorLog2
static constexpr std::enable_if_t< std::is_integral< T >::value, int > floorLog2(T x)
Definition: intmath.hh:59
logging.hh
gem5::BaseIndexingPolicy::numSets
const uint32_t numSets
The number of sets in the cache.
Definition: base.hh:77
gem5::BaseIndexingPolicy::getEntry
ReplaceableEntry * getEntry(const uint32_t set, const uint32_t way) const
Get an entry based on its set and way.
Definition: base.cc:75
gem5::BaseIndexingPolicy::extractTag
virtual Addr extractTag(const Addr addr) const
Generate the tag from the given address.
Definition: base.cc:99
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:225
gem5
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Definition: decoder.cc:40
gem5::X86ISA::addr
Bitfield< 3 > addr
Definition: types.hh:84

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