gem5  v21.1.0.2
block_bloom_filter.cc
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29 
31 
32 #include "base/bitfield.hh"
33 #include "base/logging.hh"
34 #include "params/BloomFilterBlock.hh"
35 
36 namespace gem5
37 {
38 
39 GEM5_DEPRECATED_NAMESPACE(BloomFilter, bloom_filter);
40 namespace bloom_filter
41 {
42 
43 Block::Block(const BloomFilterBlockParams &p)
44  : Base(p), masksLSBs(p.masks_lsbs),
45  masksSizes(p.masks_sizes)
46 {
47  fatal_if(masksLSBs.size() != masksSizes.size(),
48  "Masks haven't been properly provided");
49  fatal_if(masksLSBs.size() < 1,
50  "There must be at least one mask to extract an address bitfield");
51 
52  for (int i = 0; i < masksLSBs.size(); i++) {
53  fatal_if((masksSizes[i] > sizeBits) || (masksSizes[i] <= 0),
54  "The bitfields must be indexable in the filter");
56  std::numeric_limits<Addr>::digits,
57  "The total size of the bitfields cannot be bigger than the " \
58  "number of bits in an address");
59  }
60 }
61 
63 {
64 }
65 
66 void
68 {
69  filter[hash(addr)]++;
70 }
71 
72 void
74 {
75  filter[hash(addr)]--;
76 }
77 
78 int
80 {
81  return filter[hash(addr)];
82 }
83 
84 int
86 {
87  Addr hashed_addr = 0;
88  for (int i = 0; i < masksLSBs.size(); i++) {
89  hashed_addr ^=
92  }
93  assert(hashed_addr < filter.size());
94  return hashed_addr;
95 }
96 
97 } // namespace bloom_filter
98 } // namespace gem5
gem5::bloom_filter::Block::Block
Block(const BloomFilterBlockParams &p)
Definition: block_bloom_filter.cc:43
gem5::bloom_filter::Base::filter
std::vector< SatCounter8 > filter
The filter itself.
Definition: base.hh:56
gem5::bloom_filter::Base
Definition: base.hh:49
gem5::bloom_filter::Base::offsetBits
const unsigned offsetBits
Number of LSB bits to ignore from the the addresses.
Definition: base.hh:53
gem5::bloom_filter::Base::sizeBits
const int sizeBits
Number of bits needed to represent the size of the filter.
Definition: base.hh:59
gem5::bloom_filter::Block::getCount
int getCount(Addr addr) const override
Get the value stored in the corresponding filter entry of an address.
Definition: block_bloom_filter.cc:79
gem5::ArmISA::i
Bitfield< 7 > i
Definition: misc_types.hh:66
gem5::bloom_filter::Block::set
void set(Addr addr) override
Perform the filter specific function to set the corresponding entries (can be multiple) of an address...
Definition: block_bloom_filter.cc:67
bitfield.hh
gem5::MipsISA::p
Bitfield< 0 > p
Definition: pra_constants.hh:326
gem5::bloom_filter::Block::unset
void unset(Addr addr) override
Perform the filter specific function to clear the corresponding entries (can be multiple) of an addre...
Definition: block_bloom_filter.cc:73
gem5::bits
constexpr T bits(T val, unsigned first, unsigned last)
Extract the bitfield from position 'first' to 'last' (inclusive) from 'val' and right justify it.
Definition: bitfield.hh:76
gem5::Addr
uint64_t Addr
Address type This will probably be moved somewhere else in the near future.
Definition: types.hh:147
gem5::GEM5_DEPRECATED_NAMESPACE
GEM5_DEPRECATED_NAMESPACE(GuestABI, guest_abi)
gem5::bloom_filter::Block::~Block
~Block()
Definition: block_bloom_filter.cc:62
gem5::bloom_filter::Block::masksLSBs
std::vector< unsigned > masksLSBs
Position of the LSB of each mask.
Definition: block_bloom_filter.hh:70
gem5::bloom_filter::Block::masksSizes
std::vector< unsigned > masksSizes
Number of bits in each mask.
Definition: block_bloom_filter.hh:73
logging.hh
block_bloom_filter.hh
gem5::bloom_filter::Block::hash
int hash(Addr addr) const
XOR hash between bitfields of an address, provided by the mask vector.
Definition: block_bloom_filter.cc:85
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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