Kite - Detailed Router


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Track Class Referenceabstract

Structure managing one routing track. More...

Inheritance diagram for Track:
Inheritance graph
[legend]

Public Types

enum  IndexState {
  BeginIsTrackMin = 0x00000001,
  BeginIsSegmentMin = 0x00000002,
  BeginIsSegmentMax = 0x00000004,
  EndIsTrackMax = 0x00000008,
  EndIsSegmentMin = 0x00000010,
  EndIsNextSegmentMin = 0x00000020,
  EndIsSegmentMax = 0x00000040,
  BeforeFirstElement = BeginIsTrackMin |EndIsSegmentMin,
  InsideElement = BeginIsSegmentMin|EndIsSegmentMax,
  OutsideElement = BeginIsSegmentMax|EndIsNextSegmentMin,
  AfterLastElement = BeginIsSegmentMax|EndIsTrackMax,
  EmptyTrack = BeginIsTrackMin |EndIsTrackMax,
  BeginMask = BeginIsTrackMin |BeginIsSegmentMin|BeginIsSegmentMax,
  EndMask = EndIsTrackMax |EndIsSegmentMin |EndIsNextSegmentMin|EndIsSegmentMax
}
 

Public Member Functions

virtual bool isHorizontal () const =0
 
virtual bool isVertical () const =0
 
bool isLocalAssigned () const
 
RoutingPlanegetRoutingPlane () const
 
KiteEnginegetKiteEngine () const
 
virtual unsigned int getDirection () const =0
 
size_t getIndex () const
 
unsigned int getDepth () const
 
const LayergetLayer () const
 
const LayergetBlockageLayer () const
 
DbU::Unit getAxis () const
 
DbU::Unit getMin () const
 
DbU::Unit getMax () const
 
TrackgetNextTrack () const
 
TrackgetPreviousTrack () const
 
size_t getSize () const
 
virtual Point getPosition (DbU::Unit coordinate) const =0
 
TrackElementgetSegment (size_t index) const
 
TrackElementgetSegment (DbU::Unit position) const
 
TrackElementgetNext (size_t &index, Net *) const
 
TrackElementgetPrevious (size_t &index, Net *) const
 
TrackElementgetNextFixed (size_t &index) const
 
size_t find (const TrackElement *) const
 
DbU::Unit getSourcePosition (vector< TrackElement *>::iterator) const
 
DbU::Unit getMinimalPosition (size_t index, unsigned int state) const
 
DbU::Unit getMaximalPosition (size_t index, unsigned int state) const
 
Interval getFreeInterval (DbU::Unit position, Net *net=NULL) const
 
Interval getOccupiedInterval (size_t &begin) const
 
Interval expandFreeInterval (size_t &begin, size_t &end, unsigned int state, Net *) const
 
void getBeginIndex (DbU::Unit position, size_t &begin, unsigned int &state) const
 
void getOverlapBounds (Interval, size_t &begin, size_t &end) const
 
TrackCost getOverlapCost (Interval, Net *, size_t begin, size_t end, unsigned int flags) const
 
TrackCost getOverlapCost (Interval, Net *, unsigned int flags) const
 
TrackCost getOverlapCost (TrackElement *, unsigned int flags) const
 
void getTerminalWeight (Interval, Net *, size_t &count, unsigned int &weight) const
 
DbU::Unit getSourcePosition (size_t index) const
 
bool check (unsigned int &overlaps, const char *message=NULL) const
 
void invalidate ()
 
void insert (TrackElement *)
 
void insert (TrackMarker *)
 
void setSegment (TrackElement *, size_t)
 
size_t doRemoval ()
 
void doReorder ()
 

Static Public Attributes

static const size_t npos = (size_t)-1
 

Detailed Description

Structure managing one routing track.

Track Purpose

We use an array of regularly spaced Track as a geometrical fast access structure. It allows to know whether an area is used or not. The whole area may be seen as a set of adjoining tiles of fixed width but variable length.

The figure (1.b) show, for an horizontal, track the relation between y,min,max and the occupied area of the plane. min and max must take into account segment extensions (e) and the minimal distance between two rectangles (MD) of the same layer. We assume that the width of the segment, augmented of all it's contraints is no greater than TS (in fact it's how TS must be calculated).

For the whole track array, see RoutingPlane.

Track-0.png
Fig 1: Track Area

Track Implementation

A Track is implemented with a sorted vector of TrackElement. TrackElements from differents nets must not overlap. The sorting order is defined as follow:

Figure 2.b shows the details of the Track [1] of figure 1.a. Net <d> show an exemple of overlapping.

Track-1.png
Fig 2: Track Structure

In addition to the TrackSegments, the Track also manage additionnal informations through a second vector of TrackMarkers. TrackMarker are currently used only to hints at how strongly a terminal is dependant on that portion of Track to be accessed.

Indexes vs. Iterators

Numerical indexes have been prefered over iterators because they can be used more easily by objects other the Track itself for referencing. So internal managment follow the same rule, handling indexes or reference to indexes.

Update Mechanism

When a TrackElement is normaly inserted in a Track, a two way link is established. The Track has an entry in it's vector refering to TrackElement, and conversely, the TrackElement has it's track field pointing to it's owning Track.

TrackElement Removal

To remove a TrackElement from a Track, we break one of those two links: the TrackElement cease to refer to the owning Track, marking him for removal which will occurs at the next track revalidation (Track::doRemoval()). In figure 3, the TrackElement belonging to net <b> is marked for removal.

Track-2.png
Fig 3: TrackElement Removal

TrackElement Insertion

When a TrackElement is inserted into a Track, the two way link is immediatly created (but the TrackElement is not yet at it's final place in the Track's vector). Before inserting a TrackElement we check that it's been already detached (track field to NULL).

It is at that step that the TrackElement axis is actually updated through a call to TrackElement::setAxis().

Revalidation Sequence

After a Track has been modificated either the Track element vector or the MarkerElement vector (or both) has been invalidateds. Revalidation take place in three steps:

Each step must be done for all Tracks before proceeding to the next. This way a TrackElement track field doesn't get set before it has been actually removed from it's previous Track.

Main Operations on Tracks

Helper Function: Track::getBeginIndex()

Return in begin the index of the TrackElement whose minimum is immediately below the requested position on the Track axis. The second returned parameter state is a set of flags to tell how the begin index has to be interpreted.

Helper Function: Track::getOccupiedInterval()

Returns the complete interval of a set of overlapping TrackElement from the same net.

Member Enumeration Documentation

◆ IndexState

enum IndexState

Indicates how to compute the bounds of the interval enclosing a given position on track axis.

Note
According to position, the interval can be a free interval or a used interval.
Enumerator
BeginIsTrackMin 

(implies begin=0) there is no TrackElement before position

BeginIsSegmentMin 

The begin segment starts before position and ends after.

BeginIsSegmentMax 

The begin segment starts and ends before position.

EndIsTrackMax 

There is no TrackElement after position.

EndIsSegmentMin 

The begin segment starts before position.

EndIsNextSegmentMin 

The begin segment starts and ends before position. So the maximum is given by the minimum of the next TrackElement.

EndIsSegmentMax 

The begin segment starts before position and ends after.

BeforeFirstElement 

the position is before the first TrackElement.

InsideElement 

the position is inside a TrackElement.

OutsideElement 

the position is in free zone between two TrackElements.

AfterLastElement 

the position is after the end of the last element.

EmptyTrack 

the track is still empty.

BeginMask 

To extract the begin part from a combination of flags.

EndMask 

To extract the end part from a combination of flags.

Member Function Documentation

◆ isHorizontal()

bool isHorizontal ( ) const
pure virtual

Returns: true if the Track in horizontal direction.

Implemented in HorizontalTrack, and VerticalTrack.

Referenced by TrackFixedSegment::isHorizontal().

◆ isVertical()

bool isVertical ( ) const
pure virtual

Returns: true if the Track in vertical direction.

Implemented in HorizontalTrack, and VerticalTrack.

Referenced by TrackFixedSegment::isVertical().

◆ isLocalAssigned()

bool isLocalAssigned ( ) const
inline

Returns: true is the Track should be preferentially used for local routing.

◆ getRoutingPlane()

RoutingPlane * getRoutingPlane ( ) const
inline

Returns: The RoutingPlane owning this Track.

Referenced by Track::getNextTrack(), and Track::getPreviousTrack().

◆ getKiteEngine()

KiteEngine * getKiteEngine ( ) const

Returns: The KiteEngine owning this Track.

◆ getDirection()

unsigned int getDirection ( ) const
pure virtual

Returns: The direction of the Track, either Katabatic::KbHorizontal or Katabatic::KbVertical.

Implemented in HorizontalTrack, and VerticalTrack.

Referenced by TrackFixedSegment::getDirection().

◆ getIndex()

RoutingPlane * getIndex ( ) const
inline

Returns: The index of this Track in the RoutingPlane Track vector.

Referenced by Track::check(), Track::getNextTrack(), and Track::getPreviousTrack().

◆ getDepth()

unsigned int getDepth ( ) const

Returns: The depth (as given by the RoutingGauge) of the Track's layer.

◆ getLayer()

Layer * getLayer ( ) const

Returns: The Layer of the Track.

Referenced by Track::insert().

◆ getBlockageLayer()

Layer * getBlockageLayer ( ) const

Returns: The associated blockage Layer to the Track's layer.

Referenced by Track::insert().

◆ getAxis()

DbU::Unit getAxis ( ) const
inline

◆ getMin()

DbU::Unit getMin ( ) const
inline

Returns: The minimal allowed coordinate of the Track.

Referenced by Manipulator::minimize().

◆ getMax()

DbU::Unit getMax ( ) const
inline

Returns: The maximal allowed coordinate of the Track.

◆ getNextTrack()

Track * getNextTrack ( ) const

Returns: The next Track in the RoutingPlane vector. That is the one with the axis immediatly superior.

Referenced by NegociateWindow::createTrackSegment(), RoutingEvent::revalidate(), and Manipulator::ripupPerpandiculars().

◆ getPreviousTrack()

Track * getPreviousTrack ( ) const

Returns: The previous Track in the RoutingPlane vector. That is the one with the axis immediatly inferior.

Referenced by NegociateWindow::createTrackSegment().

◆ getSize()

size_t getSize ( ) const
inline

Returns: The total number of TrackSegment in the Track.

Referenced by Track::getMaximalPosition(), and Track::getSegment().

◆ getPosition()

Point getPosition ( DbU::Unit  position) const
pure virtual

Returns: the point at (position,getAxis()) for horizontal Track at or (getAxis(),position) for vertical Track.

Implemented in HorizontalTrack, and VerticalTrack.

◆ getSegment() [1/2]

TrackSegment * getSegment ( size_t  index) const
Parameters
indexThe index of the TrackSegment.
Returns
The TrackSegment at index. The result will be NULL in the follwing cases :
  • index is outside the sorted zone.
  • index points to a hole in the Track.
  • index is equal to Track::npos.

Referenced by SegmentFsm::conflictSolveByPlaceds(), NegociateWindow::createTrackSegment(), SegmentFsm::desaturate(), Manipulator::forceOverLocals(), Manipulator::forceToTrack(), Track::getSegment(), Manipulator::insertInTrack(), Manipulator::makeDogleg(), Manipulator::minimize(), and Manipulator::shrinkToTrack().

◆ getSegment() [2/2]

TrackSegment * getSegment ( DbU::Unit  position) const
Parameters
positionThe position where to search.
Returns
The TrackSegment whose starting point is immediatly inferior to position.

◆ getNext()

TrackSegment * getNext ( size_t &  index,
Net net 
) const
Parameters
indexIndex of the starting TrackSegment.
netA Net to ignore.
Returns
The next TrackSegment (NULL if not found).

Find, starting from TrackSegment at index the next TrackSegment ignoring TrackSegment from net. index is modified to point on the returned TrackSegment. If there's no next TrackSegment (NULL) then index is set to Track::npos.

Referenced by Track::expandFreeInterval(), TrackFixedSegment::getNext(), TrackSegment::getNext(), TrackElement::getNext(), and Track::getNextFixed().

◆ getPrevious()

TrackSegment * getPrevious ( size_t &  index,
Net net 
) const
Parameters
indexIndex of the starting TrackSegment.
netA Net to ignore.
Returns
The previous TrackSegment (NULL if not found).

find, starting from TrackSegment at index the previous TrackSegment ignoring TrackSegment from net. index is modified to point on the returned TrackSegment. If there's no previous TrackSegment (NULL) then index is set to Track::npos.

Referenced by Track::expandFreeInterval(), TrackFixedSegment::getPrevious(), TrackSegment::getPrevious(), and TrackElement::getPrevious().

◆ getNextFixed()

TrackSegment * getNextFixed ( size_t &  index) const
Parameters
indexIndex of the starting TrackSegment.
Returns
The first previous Fixed TrackSegment.

find, starting from TrackSegment at index the first previous with a Fixed attribute set. index is modified to point on the returned TrackSegment. If there's no previous TrackSegment (NULL) then index is set to Track::npos.

◆ find()

size_t find ( const TrackElement element) const

Returns: the index of element inside the Track. If the element do not belongs to the Track, return Track::npos.

◆ getSourcePosition() [1/2]

DbU::Unit getSourcePosition ( vector< TrackElement *>::iterator  it) const

Returns: The source position of TrackSegment pointed by iterator it. If it is equal to end() , returns zero.

◆ getMinimalPosition()

DbU::Unit getMinimalPosition ( size_t  index,
unsigned int  state 
) const

Returns: Extract the minimal position from the interval at index in accordance to state hinting.

See also:  Track::IndexState.

◆ getMaximalPosition()

DbU::Unit getMaximalPosition ( size_t  index,
unsigned int  state 
) const

Returns: Extract the maximal position from the interval at index in accordance to state hinting.

See also:  Track::IndexState.

Referenced by Track::expandFreeInterval().

◆ getFreeInterval()

Interval getFreeInterval ( DbU::Unit  position,
Net net = NULL 
) const
Parameters
positionwhere fo find a free interval.
netfor which net to find the free interval. Returns: The longuest free interval enclosing position (may be empty).

◆ getOccupiedInterval()

Interval getOccupiedInterval ( size_t &  begin) const
Parameters
beginindex of one of the TrackElement set. May be modificated. Returns: the whole interval used by a set of overlaping TrackSegment.

As TrackElement from a same net can overlap, the interval of one of them do not give the full extend of the Track occupation at this point. This function looks for all overlaping segments and returns the merged interval. Additionnaly it sets begin to the index of the lowest TrackElement of the set.

TrackOccupiedInterval-1.png
Fig 4: Track::getOccuppiedInterval()

Referenced by Track::expandFreeInterval(), Track::getBeginIndex(), and Track::getOverlapBounds().

◆ expandFreeInterval()

Interval expandFreeInterval ( size_t &  begin,
size_t &  end,
unsigned int  state,
Net net 
) const
Parameters
beginthe lowest used TrackSegment.
endthe highest used TrackSegment.
statetells how to interpret the begin & end indexes.
netthe for wich we seek place. Returns: The longuest free interval between ]begin,end[ .

Starting from the initial [begin,end] interval, expand the interval to encompass all free space or segments belonging to net. state may be used to compute the interval bounds from begin and end instead of directly using the returned interval.

Note
]begin,end[ must define a free interval between two TrackSegment.

Referenced by Track::getFreeInterval().

◆ getBeginIndex()

void getBeginIndex ( DbU::Unit  position,
size_t &  begin,
unsigned int &  state 
) const
Parameters
positionThe position where to search.
beginIndex of the immediatly inferior TrackElement.
statehow to interpret the returned begin.

Return in begin the index of the TrackElement whose minimum is immediately below the requested position on the Track axis. The second returned parameter state is a set of flags to tell how the begin index has to be interpreted.

Flags for the state are:

Based on the previous flags, we build the state parameter:

To separate flags relevant to begin and end informations, two masks are provideds:

TrackBeginIndex-1.png
Fig 3: Track::getBeginIndex()

Reminder for myself: The Track::getBeginIndex() function relies on the STL lower_bound() function. lower_bound() finds the TrackElement immediately superior to position (shown on Figure 3 by the LB label in white on black).

The relation between the returned begin index and the position is given through the state parameter.

Referenced by Track::getFreeInterval(), Track::getOverlapBounds(), and Track::getSegment().

◆ getOverlapBounds()

void getOverlapBounds ( Interval  interval,
size_t &  begin,
size_t &  end 
) const
Parameters
intervalthe overlaping interval.
beginwhere to store the starting bound.
endwhere to store the ending bound.

find the range of TrackSegment intersecting interval. Note that when the interval lower bound crosses a set of overlaping intervals from the same Net, the interval at begin will crosses the lower bound but some following of the same Net may not.

Referenced by NegociateWindow::createTrackSegment(), and Track::getOverlapCost().

◆ getOverlapCost() [1/3]

TrackCost getOverlapCost ( Interval  interval,
Net net,
size_t  begin,
size_t  end,
unsigned int  flags 
) const
Parameters
intervalthe overlaping interval.
neta Net to ignore (null cost).
beginthe starting bound.
endthe ending bound.
flagspassed to the overlap cost function.
Returns
The cost of the overlap.

Compute the cost of the overlap of interval with the range [begin,end] of TrackSegment. Any TrackSegment belonging to net will be ignored.

Referenced by Track::getOverlapCost().

◆ getOverlapCost() [2/3]

TrackCost getOverlapCost ( Interval  interval,
Net net,
unsigned int  flags 
) const
Parameters
intervalthe overlaping interval.
neta Net to ignore (null cost).
flagspassed to the overlap cost function.

Compute the overlap cost of interval with TrackSegment from the current Track, ignoring thoses belonging to net.

◆ getOverlapCost() [3/3]

TrackCost getOverlapCost ( TrackElement segment,
unsigned int  flags 
) const
Parameters
segmentunder which to compute overlap cost.
flagspassed to the overlap cost function.

Compute the overlap cost of segment with TrackSegment from the current Track (interval and net are deduced from segment).

◆ getTerminalWeight()

void getTerminalWeight ( Interval  interval,
Net net,
size_t &  count,
unsigned int &  weight 
) const
Parameters
intervalunder which to compute terminal weight.
neta net to be ignored.
countincremented of the number of track markers under the interval.
weightincremented of the sum of the weight of the track markers under the interval.

Compute and return the sum of the weight of the track markers (see TrackMarker) under interval ignoring net (that is, for net).

Remark: The referenced variables count and weight are not reset to
zero by this function. It is of the caller's responsability.

◆ getSourcePosition() [2/2]

DbU::Unit getSourcePosition ( size_t  index) const

Returns: The source position of TrackSegment at index index. If index is equal to Track::npos, returns zero.

◆ check()

bool check ( unsigned int &  overlaps,
const char *  message = NULL 
) const
Parameters
overlapsThe number of overlaping segments.
messageAn iformative message, only printed if an error occurs.
Returns
true if the Track contains no incoherencies.

Perform a complete Track check. Looks for the following incoherencies :

◆ invalidate()

void invalidate ( )

Inconditionnaly invalidate the Track, regardless if it has been modificated. The Track will be forced to be revalidated on closure of the current session.

◆ insert() [1/2]

void insert ( TrackElement segment)

Adds segment to the Track. Must only be used inside a Session. They must appears after Track::doRemoval() and before Track::doReorder().

See also:  Kite::Session.

◆ insert() [2/2]

void insert ( TrackMarker marker)

Adds marker to the Track. Must only be used inside a Session.

See also:  Kite::Session.

◆ setSegment()

void setSegment ( TrackElement element,
size_t  index 
)

Directly affect the Track entry at position index to element (use with great care).

See also:  Kite::Session.

Referenced by TrackSegment::swapTrack().

◆ doRemoval()

size_t doRemoval ( )

Returns: The number of removeds TrackSegment.

Suppress all the TrackSegment that have been withdraw from the Track. TrackSegment must be withdraw trough the TrackSegment::detach() method which sets their owning Track to NULL (the removal criterion). It uses the STL remove_if algorithm that put all the to be removed elements at the end of the vector.

See also:  Kite::Session.

◆ doReorder()

void doReorder ( )

(Re)sort the TrackElement of the vector. Must be called after:

See also:  Kite::Session.

Member Data Documentation

◆ npos

npos = (size_t)-1
static

The documentation for this class was generated from the following files:


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