149 lines
4 KiB
C++
149 lines
4 KiB
C++
|
#ifndef __FREE_LIST_HH__
|
||
|
#define __FREE_LIST_HH__
|
||
|
|
||
|
#include <iostream>
|
||
|
#include <queue>
|
||
|
|
||
|
#include "arch/alpha/isa_traits.hh"
|
||
|
#include "cpu/beta_cpu/comm.hh"
|
||
|
#include "base/trace.hh"
|
||
|
|
||
|
using namespace std;
|
||
|
|
||
|
// Question: Do I even need the number of logical registers?
|
||
|
// How to avoid freeing registers instantly? Same with ROB entries.
|
||
|
|
||
|
/**
|
||
|
* FreeList class that simply holds the list of free integer and floating
|
||
|
* point registers. Can request for a free register of either type, and
|
||
|
* also send back free registers of either type. This is a very simple
|
||
|
* class, but it should be sufficient for most implementations. Like all
|
||
|
* other classes, it assumes that the indices for the floating point
|
||
|
* registers starts after the integer registers end. Hence the variable
|
||
|
* numPhysicalIntRegs is logically equivalent to the baseFP dependency.
|
||
|
* Note that
|
||
|
* while this most likely should be called FreeList, the name "FreeList"
|
||
|
* is used in a typedef within the CPU Policy, and therefore no class
|
||
|
* can be named simply "FreeList".
|
||
|
* @todo: Give a better name to the base FP dependency.
|
||
|
*/
|
||
|
class SimpleFreeList
|
||
|
{
|
||
|
public:
|
||
|
|
||
|
private:
|
||
|
/** The list of free integer registers. */
|
||
|
queue<PhysRegIndex> freeIntRegs;
|
||
|
|
||
|
/** The list of free floating point registers. */
|
||
|
queue<PhysRegIndex> freeFloatRegs;
|
||
|
|
||
|
/** Number of logical integer registers. */
|
||
|
int numLogicalIntRegs;
|
||
|
|
||
|
/** Number of physical integer registers. */
|
||
|
int numPhysicalIntRegs;
|
||
|
|
||
|
/** Number of logical floating point registers. */
|
||
|
int numLogicalFloatRegs;
|
||
|
|
||
|
/** Number of physical floating point registers. */
|
||
|
int numPhysicalFloatRegs;
|
||
|
|
||
|
/** Total number of physical registers. */
|
||
|
int numPhysicalRegs;
|
||
|
|
||
|
public:
|
||
|
SimpleFreeList(unsigned _numLogicalIntRegs,
|
||
|
unsigned _numPhysicalIntRegs,
|
||
|
unsigned _numLogicalFloatRegs,
|
||
|
unsigned _numPhysicalFloatRegs);
|
||
|
|
||
|
PhysRegIndex getIntReg();
|
||
|
|
||
|
PhysRegIndex getFloatReg();
|
||
|
|
||
|
void addReg(PhysRegIndex freed_reg);
|
||
|
|
||
|
void addIntReg(PhysRegIndex freed_reg);
|
||
|
|
||
|
void addFloatReg(PhysRegIndex freed_reg);
|
||
|
|
||
|
bool hasFreeIntRegs()
|
||
|
{ return !freeIntRegs.empty(); }
|
||
|
|
||
|
bool hasFreeFloatRegs()
|
||
|
{ return !freeFloatRegs.empty(); }
|
||
|
|
||
|
int numFreeIntRegs()
|
||
|
{ return freeIntRegs.size(); }
|
||
|
|
||
|
int numFreeFloatRegs()
|
||
|
{ return freeFloatRegs.size(); }
|
||
|
};
|
||
|
|
||
|
inline PhysRegIndex
|
||
|
SimpleFreeList::getIntReg()
|
||
|
{
|
||
|
DPRINTF(Rename, "FreeList: Trying to get free integer register.\n");
|
||
|
if (freeIntRegs.empty()) {
|
||
|
panic("No free integer registers!");
|
||
|
}
|
||
|
|
||
|
PhysRegIndex free_reg = freeIntRegs.front();
|
||
|
|
||
|
freeIntRegs.pop();
|
||
|
|
||
|
return(free_reg);
|
||
|
}
|
||
|
|
||
|
inline PhysRegIndex
|
||
|
SimpleFreeList::getFloatReg()
|
||
|
{
|
||
|
DPRINTF(Rename, "FreeList: Trying to get free float register.\n");
|
||
|
if (freeFloatRegs.empty()) {
|
||
|
panic("No free integer registers!");
|
||
|
}
|
||
|
|
||
|
PhysRegIndex free_reg = freeFloatRegs.front();
|
||
|
|
||
|
freeFloatRegs.pop();
|
||
|
|
||
|
return(free_reg);
|
||
|
}
|
||
|
|
||
|
inline void
|
||
|
SimpleFreeList::addReg(PhysRegIndex freed_reg)
|
||
|
{
|
||
|
DPRINTF(Rename, "Freelist: Freeing register %i.\n", freed_reg);
|
||
|
//Might want to add in a check for whether or not this register is
|
||
|
//already in there. A bit vector or something similar would be useful.
|
||
|
if (freed_reg < numPhysicalIntRegs) {
|
||
|
freeIntRegs.push(freed_reg);
|
||
|
} else if (freed_reg < numPhysicalRegs) {
|
||
|
freeFloatRegs.push(freed_reg);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
inline void
|
||
|
SimpleFreeList::addIntReg(PhysRegIndex freed_reg)
|
||
|
{
|
||
|
DPRINTF(Rename, "Freelist: Freeing int register %i.\n", freed_reg);
|
||
|
|
||
|
//Might want to add in a check for whether or not this register is
|
||
|
//already in there. A bit vector or something similar would be useful.
|
||
|
freeIntRegs.push(freed_reg);
|
||
|
}
|
||
|
|
||
|
inline void
|
||
|
SimpleFreeList::addFloatReg(PhysRegIndex freed_reg)
|
||
|
{
|
||
|
DPRINTF(Rename, "Freelist: Freeing float register %i.\n", freed_reg);
|
||
|
|
||
|
//Might want to add in a check for whether or not this register is
|
||
|
//already in there. A bit vector or something similar would be useful.
|
||
|
freeFloatRegs.push(freed_reg);
|
||
|
}
|
||
|
|
||
|
#endif // __FREE_LIST_HH__
|