/*
* memoryStage - writes or reads from memory when needed
* Updates values for writebackStage
*
* params - forwardType * forward, statusType* status, bubbleType* bubble
*
*/
void memoryStage(forwardType * forward, statusType* status, bubbleType* bubble)
{
unsigned int addr = mem_addr();
unsigned int valM = M.valA;
bool memError = false;
unsigned int stat = M.stat;
if(mem_write())
{
putWord(addr, valM, &memError);
}
if(mem_read())
{
valM = getWord(addr, &memError);
}
if(memError)
stat = SADR;
//forward values
forward->M_dstM = M.dstM;
forward->M_dstE = M.dstE;
forward->m_valM = valM;
forward->M_valE = M.valE;
forward->M_Cnd = M.Cnd;
forward->M_valA = M.valA;
forward->M_icode = M.icode;
status->m_stat = stat;
bubble->M_icode = M.icode;
updateWregister(stat, M.icode, M.valE, valM, M.dstE, M.dstM);
}
/* memoryStage
* Controls the main combinational logic of the memory stage
* Params: fwdStruct *fwd - contains a bunch of forwarding info
* Returns: void
* Modifies: Writeback Register
*/
void memoryStage(fwdStruct *fwd) {
if (M.stat == SINS || M.stat == SADR || M.stat == SHLT)
canUpdateMem = FALSE;
int valM = M.valA, stat = M.stat;
bool readC = FALSE, writeC = FALSE, memError = FALSE;
memoryControl(&readC, &writeC);
int memAddr = memoryAddr();
if (readC)
valM = getWord(memAddr, &memError);
if (writeC && canUpdateMem)
putWord(memAddr, M.valA, &memError);
if (memError) {
stat = SADR;
canUpdateMem = FALSE;
}
fwd->M_valE = M.valE;
fwd->m_valM = valM;
fwd->M_dstE = M.dstE;
fwd->M_dstM = M.dstM;
fwd->M_Cnd = M.Cnd;
fwd->M_icode = M.icode;
fwd->M_valA = M.valA;
fwd->m_stat = stat;
if (!W_stall(fwd))
updateWregister(stat, M.icode, M.valE, valM, M.dstE, M.dstM);
}
