PTO-ARCH-MEMORY-MODEL-ATOMICITY

1// PTO-UNIT: {"id":"PTO-ARCH-MEMORY-MODEL-ATOMICITY","surface":"arch","classification":["memory-model","atomicity"],"depends_on":["PTO-ARCH-MEMORY-MODEL-MEMORY-EVENTS"]}2readonly func NextMemoryCoherenceRank(address: Word,3                                      size_bytes: integer {1,2,4,8})4                                      => MemoryCoherenceRank5begin6    var next_rank: integer {1..PTO_MODEL_MEMORY_EVENTS} = 1;7    if _MemoryEventCount > 0 then8        for event_number = 0 to _MemoryEventCount - 1 do9            let event = _MemoryEvents[[event_number as MemoryEventIndex]];10            if MemoryEventIsWrite(event) && event.address == address &&11               event.size_bytes == size_bytes &&12               event.coherence_rank >= next_rank then13                next_rank = (event.coherence_rank + 1) as14                    integer {1..PTO_MODEL_MEMORY_EVENTS};15            end;16        end;17    end;18    assert next_rank < PTO_MODEL_MEMORY_EVENTS;19    return next_rank as MemoryCoherenceRank;20end;21
22func ResolveCapturedReadFrom(read: MemoryEventIndex)23begin24    let read_event = _MemoryEvents[[read]];25    var found = FALSE;26    var source: MemoryEventIndex = 0;27    if read > 0 then28        for candidate_number = 0 to read - 1 do29            let candidate_index = candidate_number as MemoryEventIndex;30            let candidate = _MemoryEvents[[candidate_index]];31            if MemoryEventIsWrite(candidate) &&32               MemoryEventsShareLocation(read_event, candidate) &&33               candidate.write_value == read_event.read_value then34                found = TRUE;35                source = candidate_index;36            end;37        end;38    end;39    if found then SetMemoryReadFrom(read, source); end;40end;41
42func RecordLoadEvent(address: Word, size_bytes: integer {1,2,4,8},43                     value: Word, order: MemoryOrder)44begin45    RecordLoadEventForAgent(_CurrentMemoryAgent, address, size_bytes, value,46        order);47end;48
49func RecordLoadEventForAgent(agent: MemoryAgentId, address: Word,50                             size_bytes: integer {1,2,4,8}, value: Word,51                             order: MemoryOrder)52begin53    if _MemoryEventCaptureEnabled then54        let event = AddLoadEvent(agent, address, size_bytes,55            value, order);56        ResolveCapturedReadFrom(event);57    end;58end;59
60func RecordStoreEvent(address: Word, size_bytes: integer {1,2,4,8},61                      value: Word, order: MemoryOrder)62begin63    RecordStoreEventForAgent(_CurrentMemoryAgent, address, size_bytes, value,64        order);65end;66
67func RecordStoreEventForAgent(agent: MemoryAgentId, address: Word,68                              size_bytes: integer {1,2,4,8}, value: Word,69                              order: MemoryOrder)70begin71    if _MemoryEventCaptureEnabled then72        - = AddStoreEvent(agent, address, size_bytes, value,73            order, NextMemoryCoherenceRank(address, size_bytes));74    end;75end;76
77func RecordAtomicEvent(address: Word, size_bytes: integer {1,2,4,8},78                       read_value: Word, write_value: Word,79                       order: MemoryOrder, write_performed: boolean)80begin81    if _MemoryEventCaptureEnabled then82        let rank = if write_performed then83            NextMemoryCoherenceRank(address, size_bytes) else 0;84        let event = AddAtomicOutcomeEvent(_CurrentMemoryAgent, address,85            size_bytes, read_value, write_value, order,86            rank as MemoryCoherenceRank, write_performed);87        ResolveCapturedReadFrom(event);88    end;89end;90
91func RecordDataFenceEvent(predecessor: bits(4), successor: bits(4))92begin93    if _MemoryEventCaptureEnabled then94        - = AddDataFenceEvent(_CurrentMemoryAgent, predecessor, successor);95    end;96end;97
98func SetMemoryReadFrom(read: MemoryEventIndex, source: MemoryEventIndex)99begin100    assert read < _MemoryEventCount && source < _MemoryEventCount;101    _MemoryEvents[[read]].read_from = source;102end;103