Event Management

In OTAWA, an event is an internal effecy (usually from the hardware) causing variable execution time. Common events include cache accesses, branch prediction, variable duration instructions, etc). More...

Classes
class	otawa::StandardEventBuilder

Enumerations
enum	otawa::Event::kind_t {   otawa::Event::NONE = 0, otawa::Event::FETCH = 1, otawa::Event::MEM = 2, otawa::Event::BRANCH = 3,   otawa::Event::CUSTOM = 4 }

Functions
p::id< Event * >	otawa::EVENT ("otawa::EVENT", 0)
	Allows to hook an event to a basic block or to an edge. More...
Event::occurrence_t	otawa::operator| (Event::occurrence_t x, Event::occurrence_t y)
	Combines two event occcurrences according to the partial order (getting the maximu of x and y). More...
p::id< Event * >	otawa::PREFIX_EVENT ("otawa::PREFIX_EVENT", 0)
	Allows to hook an event to an edge and consider it as part of the prefix of the edge time. More...

Variables
p::id< Event * >	otawa::EVENT
	Allows to hook an event to a basic block or to an edge. More...
p::id< Event * >	otawa::PREFIX_EVENT
	Allows to hook an event to an edge and consider it as part of the prefix of the edge time. More...

Detailed Description

In OTAWA, an event is an internal effecy (usually from the hardware) causing variable execution time. Common events include cache accesses, branch prediction, variable duration instructions, etc).

Events are defined by:

• their latency (when they arise)
• an estimation of their occurrences (in IPET system)
• the pipeline unit they apply to,
• their type (how they relates to pipeline stages).

Events provides a very open and flexible system to relates the global hardware effects produced by global analyses with the microarchitecture time calculation algorithms.

Enumeration Type Documentation

kind_t

enum otawa::Event::kind_t

Defines the type of events, mainly which hardware feature causes the event.

Enumerator
NONE	Special null event kind.
FETCH	Event arising on the fetch stage of the instruction.
MEM	Event arising on the stage performing access to memory for data.
BRANCH	Event arising on the stage performing the branch.
CUSTOM	Event arising on a particular stage / functional unit provided by Event::unit().

Function Documentation

EVENT()

p::id<Event *> otawa::EVENT	(	"otawa::EVENT"	,
		0
	)

Allows to hook an event to a basic block or to an edge.

Feature

• STANDARD_EVENTS_FEATURE

Hooks

• BasicBlock
• Edge

operator|()

Event::occurrence_t otawa::operator|	(	Event::occurrence_t	x,
		Event::occurrence_t	y
	)

Combines two event occcurrences according to the partial order (getting the maximu of x and y).

• for x in occurrence_t, NO_OCCURRENCE <= x
• for x in occurence_t, x <= SOMETIMES.

Parameters

x	First occurrence to combine.
y	Second occurrence to combine.

Returns

Maximum of x and y.

References otawa::Event::ALWAYS, otawa::Event::NEVER, otawa::Event::NO_OCCURRENCE, otawa::Event::SOMETIMES, and otawa::ilp::x().

PREFIX_EVENT()

p::id<Event *> otawa::PREFIX_EVENT	(	"otawa::PREFIX_EVENT"	,
		0
	)

Allows to hook an event to an edge and consider it as part of the prefix of the edge time.

Feature

• STANDARD_EVENTS_FEATURE

Hooks

• Edge

Variable Documentation

EVENT

p::id<Event *> otawa::EVENT("otawa::EVENT", 0)

Allows to hook an event to a basic block or to an edge.

Feature

• STANDARD_EVENTS_FEATURE

Hooks

• BasicBlock
• Edge

Referenced by otawa::StandardEventBuilder::dumpBB().

PREFIX_EVENT

p::id<Event *> otawa::PREFIX_EVENT("otawa::PREFIX_EVENT", 0)

Allows to hook an event to an edge and consider it as part of the prefix of the edge time.

Feature

• STANDARD_EVENTS_FEATURE

Hooks

• Edge