chronon::TickableUnit

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#include <TickableUnit.hpp>

Inherits from chronon::sender::Unit

Inherited by chronon::sender::PhasedTickableUnit< Derived >, chronon::sender::factory::AutoRegisteredUnit< Derived >

Public Functions

	Name
virtual	~TickableUnit() =default
virtual void	tick() =0 Per-cycle behavior. Must complete synchronously.
virtual bool	isCompleted() const Return true to signal the simulation can stop.
	TickableUnit(std::string name)

Protected Functions

	Name
template <ValidPhase P> void	tickPhase()
void	requestTermination(TerminationReason reason, int32_t exit_code =0, std::string_view message ="")
void	requestTermination(TerminationReason reason, int32_t exit_code, uint64_t cycle, std::string_view message)
void	requestExitSyscall(int32_t exit_code)
void	requestError(std::string_view message)
void	executeTickAlwaysActive() Hot path for units that have not opted into activity scheduling.
void	executeTick() Inlined hot path executed millions of times per second.
void	advanceIdleTick(uint64_t delta) Batched inactive-cycle advance used when an entire cluster is idle.

Friends

	Name
class	TickSimulation

Additional inherited members

Public Functions inherited from chronon::sender::Unit

	Name
virtual	~Unit() =default
void	wakeAt(uint64_t cycle) Wake the unit no later than cycle. Safe for cross-thread producers.
bool	usesActivityScheduling() const
void	useFastCycleCounter() Default mode. Eliminates atomic overhead (~80% of tight-loop time).
void	useAtomicCycleCounter()
tree::TreeNode *	treeNode() const
uint32_t	tickInterval() const
UnitState	state() const
void	sleepUntil(uint64_t cycle)
void	sleepForever() Disable the tick body until an external wakeAt() or port arrival wakes it.
bool	shouldRunTickAt(uint64_t cycle) const
void	setTreeNode(tree::TreeNode * node, PortDirectory & directory =PortDirectory::instance()) Triggers registration of all pending ports to PortDirectory.
void	setTickInterval(uint32_t interval)
void	registerPort(PortBase * port)
void	registerCyclePreparedPort(PortBase * port)
const std::vector< PortBase * > &	ports() const
SimTime	physicalTime() const
Unit &	operator=(const Unit & ) =delete
Unit &	operator=(Unit && ) =delete
uint64_t	nextRunnableCycleAtOrAfter(uint64_t cycle) const
uint64_t	nextActiveCycle() const
const std::string &	name() const
uint64_t	localCycle() const
bool	isClockEdgeExecuting() const
virtual void	initialize() Called after all connections are made, before run() starts.
uint32_t	id() const
std::string	fullPath() const Returns the tree path if a TreeNode is set, else the unit name.
virtual void	finalize()
void	enableActivityScheduling()
uint8_t	crashNameLen() const
const char *	crashName() const
observe::ClockTraceStream *	clockTraceStream() const
bool	clockTopologyFrozen() const
void	clockEvent(observe::ClockEventKind kind, uint64_t transaction =0, uint64_t value =0)
ClockDomainId	clockDomainId() const Edge number in this Unit's hardware domain, never a cross-domain timestamp.
const ClockDomain &	clockDomain() const
void	addPendingPortRegistration(std::function< void(const std::string &, PortDirectory &)> registration)
uint64_t	activitySchedulingGeneration() const
bool	acceptsPortWakeups() const
	Unit(std::string name)
	Unit(const Unit & ) =delete
	Unit(Unit && ) =delete

Protected Functions inherited from chronon::sender::Unit

	Name
void	setLocalCycle(uint64_t cycle)
void	setInstanceName_(std::string name)
void	setId(uint32_t id)
void	prepareCyclePorts_()
uint64_t	localCycleAtomic() const
void	finishActiveTick_()
void	beginActiveTick_()
void	advanceLocalCycle(uint64_t delta =1) Fast path: ~0.3ns increment. Slow path (atomic): ~15ns.

Public Attributes inherited from chronon::sender::Unit

	Name
uint64_t	NEVER_ACTIVE

Detailed Description

class chronon::TickableUnit;

State-machine based simulation unit.

tick() is called every cycle; state lives in member variables. Avoids coroutine overhead and integrates with stdexec parallel execution.

class FetchUnit : public TickableUnit {
    OutPort<Instruction> out{this, "out"};
    uint64_t pc_ = 0;
    void tick() override {
        if (out.canSend()) out.send(Instruction{pc_++});
    }
};

Public Functions Documentation

function ~TickableUnit

virtual ~TickableUnit() =default

function tick

virtual void tick() =0

Per-cycle behavior. Must complete synchronously.

function isCompleted

inline virtual bool isCompleted() const

Return true to signal the simulation can stop.

function TickableUnit

inline explicit TickableUnit(
    std::string name
)

Protected Functions Documentation

function tickPhase

template <ValidPhase P>
inline void tickPhase()

Phase-templated tick for compile-time pipeline slot selection.

Override instead of tick() when using StageReg. Phase0/Phase1 dispatch is based on cycle parity. Default delegates to tick().

template<ValidPhase P>
void tickPhase() {
    if (reg_.valid<P>()) process(reg_.get<P>());
    reg_.set<P>(new_data);
}

function requestTermination

inline void requestTermination(
    TerminationReason reason,
    int32_t exit_code =0,
    std::string_view message =""
)

Request simulation termination. First request wins; the simulation stops at the next scheduler boundary, and parallel lookahead workers are signaled through the shared stop token.

function requestTermination

inline void requestTermination(
    TerminationReason reason,
    int32_t exit_code,
    uint64_t cycle,
    std::string_view message
)

Overload taking an explicit cycle (avoids cross-thread localCycle() reads in MMIO callbacks).

function requestExitSyscall

inline void requestExitSyscall(
    int32_t exit_code
)

function requestError

inline void requestError(
    std::string_view message
)

function executeTickAlwaysActive

inline void executeTickAlwaysActive()

Hot path for units that have not opted into activity scheduling.

function executeTick

inline void executeTick()

Inlined hot path executed millions of times per second.

function advanceIdleTick

inline void advanceIdleTick(
    uint64_t delta
)

Batched inactive-cycle advance used when an entire cluster is idle.

Friends

friend TickSimulation

friend class TickSimulation(
    TickSimulation 
);

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Updated on 2026-09-20 at 14:23:39 +0000