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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
46 ReturnAddrStack::reset()
47 {
48  usedEntries = 0;
49  tos = 0;
50  for (unsigned i = 0; i < numEntries; ++i)
51  addrStack[i].set(0);
52 }
53 
54 void
55 ReturnAddrStack::push(const TheISA::PCState &return_addr)
56 {
57  incrTos();
58 
59  addrStack[tos] = return_addr;
60 
61  if (usedEntries != numEntries) {
62  ++usedEntries;
63  }
64 }
65 
66 void
67 ReturnAddrStack::pop()
68 {
69  if (usedEntries > 0) {
70  --usedEntries;
71  }
72 
73  decrTos();
74 }
75 
76 void
77 ReturnAddrStack::restore(unsigned top_entry_idx,
78  const TheISA::PCState &restored)
79 {
80  tos = top_entry_idx;
81 
82  addrStack[tos] = restored;
83 
84  if (usedEntries != numEntries) {
85  ++usedEntries;
86  }
87 }
88 
89 } // namespace branch_prediction
90 } // namespace gem5
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::addrStack
std::vector< TheISA::PCState > addrStack
The RAS itself.
Definition: ras.hh:94
gem5::branch_prediction::ReturnAddrStack::pop
void pop()
Pops the top address from the RAS.
Definition: ras.cc:67
gem5::ArmISA::i
Bitfield< 7 > i
Definition: misc_types.hh:66
gem5::branch_prediction::ReturnAddrStack::push
void push(const TheISA::PCState &return_addr)
Pushes an address onto the RAS.
Definition: ras.cc:55
gem5::branch_prediction::ReturnAddrStack::restore
void restore(unsigned top_entry_idx, const TheISA::PCState &restored)
Changes index to the top of the RAS, and replaces the top address with a new target.
Definition: ras.cc:77
gem5::MipsISA::PCState
GenericISA::DelaySlotPCState< 4 > PCState
Definition: pcstate.hh:40
gem5::branch_prediction::ReturnAddrStack::numEntries
unsigned numEntries
The number of entries in the RAS.
Definition: ras.hh:97
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:103
ras.hh
gem5::branch_prediction::ReturnAddrStack::usedEntries
unsigned usedEntries
The number of used entries in the RAS.
Definition: ras.hh:100
gem5
Reference material can be found at the JEDEC website: UFS standard http://www.jedec....
Definition: decoder.cc:40
gem5::branch_prediction::ReturnAddrStack::incrTos
void incrTos()
Increments the top of stack index.
Definition: ras.hh:86
gem5::branch_prediction::ReturnAddrStack::decrTos
void decrTos()
Decrements the top of stack index.
Definition: ras.hh:90
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