diff options
Diffstat (limited to 'src/cpu')
| -rw-r--r-- | src/cpu/o3/inst_queue_impl.hh | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/src/cpu/o3/inst_queue_impl.hh b/src/cpu/o3/inst_queue_impl.hh index f70f66274..84ac5799c 100644 --- a/src/cpu/o3/inst_queue_impl.hh +++ b/src/cpu/o3/inst_queue_impl.hh @@ -1338,6 +1338,25 @@ InstructionQueue<Impl>::doSquash(ThreadID tid) ++freeEntries; } + // IQ clears out the heads of the dependency graph only when + // instructions reach writeback stage. If an instruction is squashed + // before writeback stage, its head of dependency graph would not be + // cleared out; it holds the instruction's DynInstPtr. This prevents + // freeing the squashed instruction's DynInst. + // Thus, we need to manually clear out the squashed instructions' heads + // of dependency graph. + for (int dest_reg_idx = 0; + dest_reg_idx < squashed_inst->numDestRegs(); + dest_reg_idx++) + { + PhysRegIdPtr dest_reg = + squashed_inst->renamedDestRegIdx(dest_reg_idx); + if (dest_reg->isFixedMapping()){ + continue; + } + assert(dependGraph.empty(dest_reg->flatIndex())); + dependGraph.clearInst(dest_reg->flatIndex()); + } instList[tid].erase(squash_it--); ++iqSquashedInstsExamined; } |