gem5  v21.2.0.0
ras.cc
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28 
29 #include "cpu/pred/ras.hh"
30 
31 namespace gem5
32 {
33 
34 namespace branch_prediction
35 {
36 
37 void
38 ReturnAddrStack::init(unsigned _numEntries)
39 {
40  numEntries = _numEntries;
41  addrStack.resize(numEntries);
42  reset();
43 }
44 
45 void
47 {
48  usedEntries = 0;
49  tos = 0;
50 }
51 
52 void
54 {
55  incrTos();
56 
57  set(addrStack[tos], return_addr);
58 
59  if (usedEntries != numEntries) {
60  ++usedEntries;
61  }
62 }
63 
64 void
66 {
67  if (usedEntries > 0) {
68  --usedEntries;
69  }
70 
71  decrTos();
72 }
73 
74 void
75 ReturnAddrStack::restore(unsigned top_entry_idx, const PCStateBase *restored)
76 {
77  tos = top_entry_idx;
78 
79  set(addrStack[tos], restored);
80 
81  if (usedEntries != numEntries) {
82  ++usedEntries;
83  }
84 }
85 
86 } // namespace branch_prediction
87 } // namespace gem5
gem5::branch_prediction::ReturnAddrStack::addrStack
std::vector< std::unique_ptr< PCStateBase > > addrStack
The RAS itself.
Definition: ras.hh:98
gem5::branch_prediction::ReturnAddrStack::init
void init(unsigned numEntries)
Initializes RAS with a specified number of entries.
Definition: ras.cc:38
gem5::branch_prediction::ReturnAddrStack::pop
void pop()
Pops the top address from the RAS.
Definition: ras.cc:65
gem5::branch_prediction::ReturnAddrStack::numEntries
unsigned numEntries
The number of entries in the RAS.
Definition: ras.hh:101
gem5::branch_prediction::ReturnAddrStack::restore
void restore(unsigned top_entry_idx, const PCStateBase *restored)
Changes index to the top of the RAS, and replaces the top address with a new target.
Definition: ras.cc:75
gem5::branch_prediction::ReturnAddrStack::reset
void reset()
Definition: ras.cc:46
gem5::branch_prediction::ReturnAddrStack::tos
unsigned tos
The top of stack index.
Definition: ras.hh:107
ras.hh
gem5::branch_prediction::ReturnAddrStack::usedEntries
unsigned usedEntries
The number of used entries in the RAS.
Definition: ras.hh:104
gem5::PCStateBase
Definition: pcstate.hh:57
gem5
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Definition: tlb.cc:60
gem5::branch_prediction::ReturnAddrStack::incrTos
void incrTos()
Increments the top of stack index.
Definition: ras.hh:84
gem5::branch_prediction::ReturnAddrStack::decrTos
void decrTos()
Decrements the top of stack index.
Definition: ras.hh:92
gem5::branch_prediction::ReturnAddrStack::push
void push(const PCStateBase &return_addr)
Pushes an address onto the RAS.
Definition: ras.cc:53

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