MauPower::MauFeatures Class Reference

#include <mau_power.h>

Public Types
using	PowerLogging = Logging::Power_Schema_Logger

Public Member Functions
bool	are_there_more_tables (gress_t gress, int start_stage) const
int	compute_pipe_latency (gress_t gress) const
int	compute_pred_cycle (gress_t gress, int stage) const
int	compute_stage_latency (gress_t gress, int stage) const
std::ostream &	emit_dep_asm (std::ostream &out, gress_t g, int stage) const
mau_dep_t	get_dependency_for_gress_stage (gress_t g, int stage) const
int	get_max_selector_words (gress_t gress, int stage) const
void	log_json_stage_characteristics (gress_t g, PowerLogging *logger) const
void	print_features (std::ostream &out, gress_t gress) const
void	print_latency (std::ostream &out, gress_t gress) const
bool	requires_dep_asm (gress_t g, int stage) const
void	set_dependency_for_gress_stage (gress_t g, int stage, mau_dep_t dep)
bool	stage_has_chained_feature (gress_t gress, int stage, stage_feature_t feature) const
bool	stage_has_feature (gress_t gress, int stage, stage_feature_t feature) const
bool	try_convert_to_match_dep ()
void	update_deps_for_device ()

Public Attributes
std::map< UniqueId, bool >	counter_runs_at_eop_
bitvec	has_exact_ [kNumberGress]
bitvec	has_meter_lpf_or_wred_ [kNumberGress]
bitvec	has_selector_ [kNumberGress]
bitvec	has_stateful_ [kNumberGress]
bitvec	has_stats_ [kNumberGress]
bitvec	has_tcam_ [kNumberGress]
dyn_vector< int >	max_selector_words_ [kNumberGress]
std::map< UniqueId, bool >	meter_is_lpf_or_wred_
std::map< UniqueId, bool >	meter_runs_at_eop_
std::map< UniqueId, int >	selector_group_size_
dyn_vector< std::vector< const IR::MAU::Table * > >	stage_to_tables_ [kNumberGress]
std::map< UniqueId, int >	table_to_stage_
std::map< UniqueId, const IR::MAU::Table * >	uid_to_table_

Static Public Attributes
static const int	kNumberGress = GRESS_T_COUNT

Detailed Description

A class to represent MAU stage characteristics, such as:

• what features are in use in each MAU stage in each gress
• the dependency to the previous stage for each MAU stage in each gress

Member Function Documentation

are_there_more_tables()

bool MauPower::MauFeatures::are_there_more_tables	(	gress_t	gress,
		int	start_stage ) const

Returns true if there are tables remaining in a particular gress in the start stage until the last MAU stage.

compute_pipe_latency()

int MauPower::MauFeatures::compute_pipe_latency

(

gress_t

gress

)

const

Parameters

gress

The thread of compute.

Returns

A specific pipeline latency (in clock cycles).

compute_pred_cycle()

int MauPower::MauFeatures::compute_pred_cycle	(	gress_t	gress,
		int	stage ) const

Parameters

gress	The thread of compute.
stage	The MAU stage number, running 0 to n-1.

Returns

The predication cycle of a specific MAU gress-stage (in clock cycles)

compute_stage_latency()

int MauPower::MauFeatures::compute_stage_latency	(	gress_t	gress,
		int	stage ) const

Parameters

gress	The thread of compute.
stage	The MAU stage number, running 0 to n-1.

Returns

The stage latency of a specific MAU gress-stage (in clock cycles).

emit_dep_asm()

std::ostream & MauPower::MauFeatures::emit_dep_asm	(	std::ostream &	out,
		gress_t	g,
		int	stage ) const

Emits information that needs to be communicated to assembly for register configuration. Currently, this is the MAU stage dependencies.

get_dependency_for_gress_stage()

mau_dep_t MauPower::MauFeatures::get_dependency_for_gress_stage	(	gress_t	g,
		int	stage ) const

Parameters

g	The thread of compute.
stage	The MAU stage number, running 0 to n-1.

Returns

Stage dependency type to the previous MAU stage.

get_max_selector_words()

int MauPower::MauFeatures::get_max_selector_words	(	gress_t	gress,
		int	stage ) const

Parameters

gress	The thread of compute.
stage	The MAU stage number, running 0 to n-1.

Returns

The maximum number of RAM words required to hold the largest selector group. For example, a group size of 120 results in 1 being returned. A group size of 121 results in 2 being returned.

log_json_stage_characteristics()

void MauPower::MauFeatures::log_json_stage_characteristics	(	gress_t	g,
		PowerLogging *	logger ) const

Produces the power.json output.

print_features()

void MauPower::MauFeatures::print_features	(	std::ostream &	out,
		gress_t	gress ) const

Produces lovely text tables showing features and dependencies.

print_latency()

void MauPower::MauFeatures::print_latency	(	std::ostream &	out,
		gress_t	gress ) const

Produces lovely text tables showing latencies and dependencies.

requires_dep_asm()

bool MauPower::MauFeatures::requires_dep_asm	(	gress_t	g,
		int	stage ) const

Return true if some asm code is required for the stage for correct behavior, even if no tables are present

stage_has_chained_feature()

bool MauPower::MauFeatures::stage_has_chained_feature	(	gress_t	gress,
		int	stage,
		stage_feature_t	feature ) const

Parameters

gress	The thread of compute.
stage	The MAU stage number, running 0 to n-1.
feature	The MAU feature.

Returns

Boolean indicating if a particular stage should be considered as having a particular feature for timing balance reasons. This is only applicable when the stage is not separated by match dependencies with its adjacent stages.

stage_has_feature()

bool MauPower::MauFeatures::stage_has_feature	(	gress_t	gress,
		int	stage,
		stage_feature_t	feature ) const

Parameters

gress	The thread of compute.
stage	The MAU stage number, running 0 to n-1.
feature	The MAU feature.

Returns

Boolean indicating if a particular stage has a given feature.

try_convert_to_match_dep()

bool MauPower::MauFeatures::try_convert_to_match_dep

(

)

Attempts to convert a MAU stage dependency to match dependent. If a stage can be changed, the change is performed and this function returns true. Otherwise, it returns false.

Returns

Boolean indicating if a MAU stage in any thread was converted to match dependent.

update_deps_for_device()

void MauPower::MauFeatures::update_deps_for_device

(

)

Removes concurrent dependency type if dealing with Tofino2 or later.