ActionBus Class Reference

Classes
struct	Slot

Public Member Functions
virtual void	alloc_field (Table *, ActionBusSource src, unsigned offset, unsigned sizes_needed)
void	do_alloc (Table *tbl, ActionBusSource src, unsigned use, int lobyte, int bytes, unsigned offset)
int	find (const ActionBusSource &src, int lo, int hi, int size, int pos=-1, int *len=0)
int	find (const char *name, int lo, int hi, int size, int *len=0)
int	find (const char *name, TableOutputModifier mod, int lo, int hi, int size, int *len=0)
	find an action bus slot that contains the requested thing.
int	find (const std::string &name, int lo, int hi, int size, int *len=0)
int	find (const std::string &name, TableOutputModifier mod, int lo, int hi, int size, int *len=0)
int	find (Table *attached, TableOutputModifier mod, int lo, int hi, int size, int *len=0)
void	need_alloc (Table *tbl, const ActionBusSource &src, unsigned lo, unsigned hi, unsigned size)
void	need_alloc (Table *tbl, Table *attached, TableOutputModifier mod, unsigned lo, unsigned hi, unsigned size)
void	pass1 (Table *tbl)
void	pass2 (Table *tbl)
void	pass3 (Table *tbl)
unsigned	size ()
auto	slots () const
template<class REGS>
void	write_action_regs (REGS &regs, Table *tbl, int homerow, unsigned action_slice)
template<class REGS>
void	write_immed_regs (REGS &regs, Table *tbl)

Static Public Member Functions
static std::unique_ptr< ActionBus >	create ()
static std::unique_ptr< ActionBus >	create (Table *, VECTOR(pair_t) &)
static int	find (Stage *stage, ActionBusSource src, int lo, int hi, int size, int *len=0)

Public Attributes
int	lineno

Static Public Attributes
static const unsigned	size_masks [8] = {7, 7, 15, 15, 31, 31, 31, 31}

Protected Member Functions
	ActionBus (Table *, VECTOR(pair_t) &)
bool	check_atcam_sharing (Table *tbl1, Table *tbl2)
bool	check_slot_sharing (ActionBus::Slot &slot, bitvec &action_bus)
int	find_free (Table *tbl, unsigned min, unsigned max, unsigned step, unsigned lobyte, unsigned bytes)
int	find_merge (Table *tbl, int offset, int bytes, int use)
void	setup_slot (int lineno, Table *tbl, const char *name, unsigned idx, ActionBusSource src, unsigned sz, unsigned off)

Static Protected Member Functions
static bool	compatible (const ActionBusSource &a, unsigned a_off, const ActionBusSource &b, unsigned b_off)

Protected Attributes
std::vector< std::array< unsigned, ACTION_HV_XBAR_SLICES > >	action_hv_slice_use
ordered_map< unsigned, Slot >	by_byte
bitvec	byte_use
ordered_map< ActionBusSource, ordered_map< unsigned, unsigned > >	need_place

Friends
std::ostream &	operator<< (std::ostream &out, const ActionBus &a)
std::ostream &	operator<< (std::ostream &out, const Slot &sl)

Member Function Documentation

find()

int ActionBus::find	(	const char *	name,
		TableOutputModifier	mod,
		int	lo,
		int	hi,
		int	size,
		int *	len = 0 )

find an action bus slot that contains the requested thing.

ActionBus::find

Overloads allow looking for different kinds of things – a Format::Field, a HashDistribution, a RandomNumberGen, or something by name (generally a table output).

Parameters

f	a Format::Field to look for
name	named slot to look for – generally a table output, but may be a field
hd	a HashDistribution to look for
rng	a RandomNumberGen to look for
lo,hi	range of bits in the thing specified by the first arg
size	bitmask of needed size classes – 3 bits that denote need for a 8/16/32 bit actionbus slot. Generally will only have 1 bit set, but might be 0.

find_free()

int ActionBus::find_free ( Table * tbl, unsigned min, unsigned max, unsigned step, unsigned lobyte, unsigned bytes )

protected

find_free – find a free slot on the action output bus for some data. Looks through bytes in the range min..max for a free space where we can put 'bytes' bytes from an action input bus starting at 'lobyte'. 'step' is an optimization to only check every step bytes as we know alignment restrictions mean those are the only possible aligned spots

find_merge()

int ActionBus::find_merge ( Table * tbl, int offset, int bytes, int use )

protected

find_merge – find any adjacent/overlapping data on the action input bus that means the data at 'offset' actually already on the action output bus offset offset (in bits) on the action input bus of the data we're interested in bytes how many bytes of data on the action input bus use bitmask of the sizes of phv that need to access this on the action output bus