759ff4b910
build/SConstruct:
Include Ozone CPU models.
cpu/cpu_models.py:
Include OzoneCPU models.
--HG--
extra : convert_revision : 51a016c216cacd2cc613eed79653026c2edda4b3
77 lines
2.2 KiB
C++
77 lines
2.2 KiB
C++
|
|
#ifndef __CPU_OZONE_NULL_PREDICTOR_HH__
|
|
#define __CPU_OZONE_NULL_PREDICTOR_HH__
|
|
|
|
#include "arch/isa_traits.hh"
|
|
#include "cpu/inst_seq.hh"
|
|
|
|
template <class Impl>
|
|
class NullPredictor
|
|
{
|
|
public:
|
|
typedef typename Impl::Params Params;
|
|
typedef typename Impl::DynInstPtr DynInstPtr;
|
|
|
|
NullPredictor(Params *p) { }
|
|
|
|
struct BPredInfo {
|
|
BPredInfo()
|
|
: PC(0), nextPC(0)
|
|
{ }
|
|
|
|
BPredInfo(const Addr &pc, const Addr &next_pc)
|
|
: PC(pc), nextPC(next_pc)
|
|
{ }
|
|
|
|
Addr PC;
|
|
Addr nextPC;
|
|
};
|
|
|
|
BPredInfo lookup(Addr &PC) { return BPredInfo(PC, PC+4); }
|
|
|
|
void undo(BPredInfo &bp_info) { return; }
|
|
|
|
/**
|
|
* Predicts whether or not the instruction is a taken branch, and the
|
|
* target of the branch if it is taken.
|
|
* @param inst The branch instruction.
|
|
* @param PC The predicted PC is passed back through this parameter.
|
|
* @param tid The thread id.
|
|
* @return Returns if the branch is taken or not.
|
|
*/
|
|
bool predict(DynInstPtr &inst, Addr &PC, unsigned tid)
|
|
{ return false; }
|
|
|
|
/**
|
|
* Tells the branch predictor to commit any updates until the given
|
|
* sequence number.
|
|
* @param done_sn The sequence number to commit any older updates up until.
|
|
* @param tid The thread id.
|
|
*/
|
|
void update(const InstSeqNum &done_sn, unsigned tid) { }
|
|
|
|
/**
|
|
* Squashes all outstanding updates until a given sequence number.
|
|
* @param squashed_sn The sequence number to squash any younger updates up
|
|
* until.
|
|
* @param tid The thread id.
|
|
*/
|
|
void squash(const InstSeqNum &squashed_sn, unsigned tid) { }
|
|
|
|
/**
|
|
* Squashes all outstanding updates until a given sequence number, and
|
|
* corrects that sn's update with the proper address and taken/not taken.
|
|
* @param squashed_sn The sequence number to squash any younger updates up
|
|
* until.
|
|
* @param corr_target The correct branch target.
|
|
* @param actually_taken The correct branch direction.
|
|
* @param tid The thread id.
|
|
*/
|
|
void squash(const InstSeqNum &squashed_sn, const Addr &corr_target,
|
|
bool actually_taken, unsigned tid)
|
|
{ }
|
|
|
|
};
|
|
|
|
#endif // __CPU_OZONE_NULL_PREDICTOR_HH__
|