diff options
Diffstat (limited to 'src/cpu/o3/decode_impl.hh')
-rw-r--r-- | src/cpu/o3/decode_impl.hh | 69 |
1 files changed, 4 insertions, 65 deletions
diff --git a/src/cpu/o3/decode_impl.hh b/src/cpu/o3/decode_impl.hh index 314864f94..ce6738456 100644 --- a/src/cpu/o3/decode_impl.hh +++ b/src/cpu/o3/decode_impl.hh @@ -49,8 +49,6 @@ DefaultDecode<Impl>::DefaultDecode(O3CPU *_cpu, Params *params) stalls[i].rename = false; stalls[i].iew = false; stalls[i].commit = false; - - squashAfterDelaySlot[i] = false; } // @todo: Make into a parameter @@ -275,20 +273,16 @@ DefaultDecode<Impl>::squash(DynInstPtr &inst, unsigned tid) ///explicitly for ISAs with delay slots. toFetch->decodeInfo[tid].nextNPC = inst->branchTarget() + sizeof(TheISA::MachInst); + toFetch->decodeInfo[tid].nextMicroPC = inst->readMicroPC(); #if ISA_HAS_DELAY_SLOT toFetch->decodeInfo[tid].branchTaken = inst->readNextNPC() != (inst->readNextPC() + sizeof(TheISA::MachInst)); - - toFetch->decodeInfo[tid].bdelayDoneSeqNum = bdelayDoneSeqNum[tid]; - squashAfterDelaySlot[tid] = false; - - InstSeqNum squash_seq_num = bdelayDoneSeqNum[tid]; #else toFetch->decodeInfo[tid].branchTaken = inst->readNextPC() != (inst->readPC() + sizeof(TheISA::MachInst)); +#endif InstSeqNum squash_seq_num = inst->seqNum; -#endif // Might have to tell fetch to unblock. if (decodeStatus[tid] == Blocked || @@ -309,30 +303,10 @@ DefaultDecode<Impl>::squash(DynInstPtr &inst, unsigned tid) // Clear the instruction list and skid buffer in case they have any // insts in them. while (!insts[tid].empty()) { - -#if ISA_HAS_DELAY_SLOT - if (insts[tid].front()->seqNum <= squash_seq_num) { - DPRINTF(Decode, "[tid:%i]: Cannot remove incoming decode " - "instructions before delay slot [sn:%i]. %i insts" - "left in decode.\n", tid, squash_seq_num, - insts[tid].size()); - break; - } -#endif insts[tid].pop(); } while (!skidBuffer[tid].empty()) { - -#if ISA_HAS_DELAY_SLOT - if (skidBuffer[tid].front()->seqNum <= squash_seq_num) { - DPRINTF(Decode, "[tid:%i]: Cannot remove skidBuffer " - "instructions before delay slot [sn:%i]. %i insts" - "left in decode.\n", tid, squash_seq_num, - insts[tid].size()); - break; - } -#endif skidBuffer[tid].pop(); } @@ -760,48 +734,13 @@ DefaultDecode<Impl>::decodeInsts(unsigned tid) // Might want to set some sort of boolean and just do // a check at the end -#if !ISA_HAS_DELAY_SLOT squash(inst, inst->threadNumber); Addr target = inst->branchTarget(); - inst->setPredTarg(target, target + sizeof(TheISA::MachInst)); + //The micro pc after an instruction level branch should be 0 + inst->setPredTarg(target, target + sizeof(TheISA::MachInst), 0); break; -#else - // If mispredicted as taken, then ignore delay slot - // instruction... else keep delay slot and squash - // after it is sent to rename - if (inst->readPredTaken() && inst->isCondDelaySlot()) { - DPRINTF(Decode, "[tid:%i]: Conditional delay slot inst." - "[sn:%i] PC %#x mispredicted as taken.\n", tid, - inst->seqNum, inst->PC); - bdelayDoneSeqNum[tid] = inst->seqNum; - squash(inst, inst->threadNumber); - Addr target = inst->branchTarget(); - inst->setPredTarg(target, - target + sizeof(TheISA::MachInst)); - break; - } else { - DPRINTF(Decode, "[tid:%i]: Misprediction detected at " - "[sn:%i] PC %#x, will squash after delay slot " - "inst. is sent to Rename\n", - tid, inst->seqNum, inst->PC); - bdelayDoneSeqNum[tid] = inst->seqNum + 1; - squashAfterDelaySlot[tid] = true; - squashInst[tid] = inst; - continue; - } -#endif } } - - if (squashAfterDelaySlot[tid]) { - assert(!inst->isSquashed()); - squash(squashInst[tid], squashInst[tid]->threadNumber); - Addr target = squashInst[tid]->branchTarget(); - squashInst[tid]->setPredTarg(target, - target + sizeof(TheISA::MachInst)); - assert(!inst->isSquashed()); - break; - } } // If we didn't process all instructions, then we will need to block |