diff options
Diffstat (limited to 'src/cpu')
-rw-r--r-- | src/cpu/o3/fetch_impl.hh | 39 |
1 files changed, 9 insertions, 30 deletions
diff --git a/src/cpu/o3/fetch_impl.hh b/src/cpu/o3/fetch_impl.hh index 5cd2e3514..815935db3 100644 --- a/src/cpu/o3/fetch_impl.hh +++ b/src/cpu/o3/fetch_impl.hh @@ -1114,15 +1114,17 @@ DefaultFetch<Impl>::fetch(bool &status_change) // ended this fetch block. bool predicted_branch = false; - // Need to keep track of whether or not a delay slot - // instruction has been fetched - for (; offset < cacheBlkSize && numInst < fetchWidth && - (!predicted_branch || delaySlotInfo[tid].numInsts > 0); + !predicted_branch; ++numInst) { + // If we're branching after this instruction, quite fetching + // from the same block then. + predicted_branch = + (fetch_PC + sizeof(TheISA::MachInst) != fetch_NPC); + // Get a sequence number. inst_seq = cpu->getAndIncrementInstSeq(); @@ -1166,8 +1168,7 @@ DefaultFetch<Impl>::fetch(bool &status_change) instruction->staticInst, instruction->readPC()); - predicted_branch = lookupAndUpdateNextPC(instruction, next_PC, - next_NPC); + lookupAndUpdateNextPC(instruction, next_PC, next_NPC); // Add instruction to the CPU's list of instructions. instruction->setInstListIt(cpu->addInst(instruction)); @@ -1183,6 +1184,7 @@ DefaultFetch<Impl>::fetch(bool &status_change) // Move to the next instruction, unless we have a branch. fetch_PC = next_PC; + fetch_NPC = next_NPC; if (instruction->isQuiesce()) { DPRINTF(Fetch, "Quiesce instruction encountered, halting fetch!", @@ -1194,29 +1196,6 @@ DefaultFetch<Impl>::fetch(bool &status_change) } offset += instSize; - -#if ISA_HAS_DELAY_SLOT - if (predicted_branch) { - delaySlotInfo[tid].branchSeqNum = inst_seq; - - DPRINTF(Fetch, "[tid:%i]: Delay slot branch set to [sn:%i]\n", - tid, inst_seq); - continue; - } else if (delaySlotInfo[tid].numInsts > 0) { - --delaySlotInfo[tid].numInsts; - - // It's OK to set PC to target of branch - if (delaySlotInfo[tid].numInsts == 0) { - delaySlotInfo[tid].targetReady = true; - - // Break the looping condition - predicted_branch = true; - } - - DPRINTF(Fetch, "[tid:%i]: %i delay slot inst(s) left to" - " process.\n", tid, delaySlotInfo[tid].numInsts); - } -#endif } if (offset >= cacheBlkSize) { @@ -1225,7 +1204,7 @@ DefaultFetch<Impl>::fetch(bool &status_change) } else if (numInst >= fetchWidth) { DPRINTF(Fetch, "[tid:%i]: Done fetching, reached fetch bandwidth " "for this cycle.\n", tid); - } else if (predicted_branch && delaySlotInfo[tid].numInsts <= 0) { + } else if (predicted_branch) { DPRINTF(Fetch, "[tid:%i]: Done fetching, predicted branch " "instruction encountered.\n", tid); } |