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inorder-mdu: multiplier latency fix

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mdu was workign incorrectly for 4+ latency due to incorrectly assuming
multiply was finished the next stage
This commit is contained in:
Korey Sewell 2009-09-17 15:45:27 -04:00
parent 931405da2f
commit 6f7e196113
2 changed files with 33 additions and 1 deletions
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32
src/cpu/inorder/resources/mult_div_unit.cc
View file

@ -91,7 +91,32 @@ MultDivUnit::freeSlot(int slot_idx)
Resource::freeSlot(slot_idx);
}
//@TODO: Should we push this behavior into base-class to generically
// accomodate all multicyle resources?
void
MultDivUnit::requestAgain(DynInstPtr inst, bool &service_request)
{
ResReqPtr mult_div_req = findRequest(inst);
assert(mult_div_req);
service_request = true;
// Check to see if this instruction is requesting the same command
// or a different one
if (mult_div_req->cmd != inst->resSched.top()->cmd) {
// If different, then update command in the request
mult_div_req->cmd = inst->resSched.top()->cmd;
DPRINTF(InOrderMDU,
"[tid:%i]: [sn:%i]: Updating the command for this instruction\n",
inst->readTid(), inst->seqNum);
} else {
// If same command, just check to see if memory access was completed
// but dont try to re-execute
DPRINTF(InOrderMDU,
"[tid:%i]: [sn:%i]: requesting this resource again\n",
inst->readTid(), inst->seqNum);
}
}
int
MultDivUnit::getSlot(DynInstPtr inst)
{
@ -232,8 +257,13 @@ MultDivUnit::execute(int slot_num)
// counting down the time
{
DPRINTF(InOrderMDU, "End MDU called ...\n");
if (mult_div_req->getInst()->isExecuted())
if (mult_div_req->getInst()->isExecuted()) {
DPRINTF(InOrderMDU, "Mult/Div finished.\n");
mult_div_req->done();
} else {
mult_div_req->setCompleted(false);
}
}
break;

2
src/cpu/inorder/resources/mult_div_unit.hh
View file

@ -82,6 +82,8 @@ class MultDivUnit : public Resource {
/** Register extra resource stats */
virtual void regStats();
void requestAgain(DynInstPtr inst, bool &try_request);
protected:
/** Latency & Repeat Rate for Multiply Insts */
unsigned multRepeatRate;