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ras.cc
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28 
29 #include "cpu/pred/ras.hh"
30 
31 void
32 ReturnAddrStack::init(unsigned _numEntries)
33 {
34  numEntries = _numEntries;
35  addrStack.resize(numEntries);
36  reset();
37 }
38 
39 void
40 ReturnAddrStack::reset()
41 {
42  usedEntries = 0;
43  tos = 0;
44  for (unsigned i = 0; i < numEntries; ++i)
45  addrStack[i].set(0);
46 }
47 
48 void
49 ReturnAddrStack::push(const TheISA::PCState &return_addr)
50 {
51  incrTos();
52 
53  addrStack[tos] = return_addr;
54 
55  if (usedEntries != numEntries) {
56  ++usedEntries;
57  }
58 }
59 
60 void
61 ReturnAddrStack::pop()
62 {
63  if (usedEntries > 0) {
64  --usedEntries;
65  }
66 
67  decrTos();
68 }
69 
70 void
71 ReturnAddrStack::restore(unsigned top_entry_idx,
72  const TheISA::PCState &restored)
73 {
74  tos = top_entry_idx;
75 
76  addrStack[tos] = restored;
77 
78  if (usedEntries != numEntries) {
79  ++usedEntries;
80  }
81 }
ReturnAddrStack::init
void init(unsigned numEntries)
Initializes RAS with a specified number of entries.
Definition: ras.cc:32
ReturnAddrStack::decrTos
void decrTos()
Decrements the top of stack index.
Definition: ras.hh:84
ReturnAddrStack::tos
unsigned tos
The top of stack index.
Definition: ras.hh:97
ArmISA::i
Bitfield< 7 > i
Definition: miscregs_types.hh:63
ReturnAddrStack::addrStack
std::vector< TheISA::PCState > addrStack
The RAS itself.
Definition: ras.hh:88
ReturnAddrStack::usedEntries
unsigned usedEntries
The number of used entries in the RAS.
Definition: ras.hh:94
ReturnAddrStack::reset
void reset()
Definition: ras.cc:40
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:71
ReturnAddrStack::incrTos
void incrTos()
Increments the top of stack index.
Definition: ras.hh:80
MipsISA::PCState
GenericISA::DelaySlotPCState< MachInst > PCState
Definition: types.hh:41
ReturnAddrStack::numEntries
unsigned numEntries
The number of entries in the RAS.
Definition: ras.hh:91
ReturnAddrStack::push
void push(const TheISA::PCState &return_addr)
Pushes an address onto the RAS.
Definition: ras.cc:49
ReturnAddrStack::pop
void pop()
Pops the top address from the RAS.
Definition: ras.cc:61
ras.hh
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