cache — Classic Cache Hierarchy

classDiagram
    class ClockedObject {
        +clockPeriod()
        +curCycle()
    }
    class BaseCache {
        -MSHRQueue mshrQueue
        -WriteQueue writeBuffer
        -BaseTags* tags
        -BasePrefetcher* prefetcher
        +recvTimingReq()
        +recvTimingResp()
        +handleFill()
        +satisfyRequest()
    }
    class Cache {
        -doFastWrites: bool
        -outstandingSnoop: set
        +serviceMSHRTargets()
        +handleSnoop()
        +recvTimingSnoopReq()
    }
    class NoncoherentCache {
        +handleTimingReqMiss()
        +serviceMSHRTargets()
    }
    class MSHR {
        -targets: TargetList
        -deferredTargets: TargetList
        +allocate()
        +deallocate()
        +getTarget()
    }
    class WriteQueueEntry {
        +isFull(): bool
    }
    class BaseTags {
        +accessBlock()
        +findBlock()
        +insertBlock()
    }
    class BaseSetAssoc
    class FALRU
    class SectorTags
    class CompressedTags
    class ReplacementPolicy_Base {
        +getVictim()
        +reset()
        +touch()
    }
    class LRURP
    class FIFORP
    class BIPRP
    class BRRIPRP
    class SHiPRP
    class TreePLRURP
    class BasePrefetcher {
        +notify()
        +getPacket()
    }
    class Queued
    class Stride
    class BOP
    class AMPM

    ClockedObject <|-- BaseCache
    BaseCache <|-- Cache
    BaseCache <|-- NoncoherentCache
    BaseCache *-- MSHR
    BaseCache *-- WriteQueueEntry
    BaseCache *-- BaseTags
    BaseCache *-- BasePrefetcher
    BaseTags <|-- BaseSetAssoc
    BaseTags <|-- FALRU
    BaseTags <|-- SectorTags
    SectorTags <|-- CompressedTags
    ReplacementPolicy_Base <|-- LRURP
    ReplacementPolicy_Base <|-- FIFORP
    ReplacementPolicy_Base <|-- BIPRP
    BIPRP <|-- BRRIPRP
    ReplacementPolicy_Base <|-- SHiPRP
    ReplacementPolicy_Base <|-- TreePLRURP
    BasePrefetcher <|-- Queued
    Queued <|-- Stride
    Queued <|-- BOP
    Queued <|-- AMPM
  

flowchart TD
    REQ["recvTimingReq()"]
    LOOKUP["Tag Lookup"]
    HIT{"Hit?"}
    RESP["Send Response"]
    MSHR_CHK{"MSHR exists?"}
    COALESCE["Coalesce into MSHR"]
    ALLOC["Allocate MSHR"]
    SEND["sendTimingReq() downstream"]
    FILL["handleFill()"]
    VICTIM["Select victim (RP)"]
    WB{"Dirty victim?"}
    WBACK["Writeback victim"]
    INSERT["Insert new block"]
    DEALLOC["Deallocate MSHR"]

    REQ --> LOOKUP
    LOOKUP --> HIT
    HIT -->|Yes| RESP
    HIT -->|No| MSHR_CHK
    MSHR_CHK -->|Yes| COALESCE
    MSHR_CHK -->|No| ALLOC
    ALLOC --> SEND
    SEND -->|Response arrives| FILL
    FILL --> VICTIM
    VICTIM --> WB
    WB -->|Yes| WBACK
    WB -->|No| INSERT
    WBACK --> INSERT
    INSERT --> DEALLOC
    DEALLOC --> RESP