dpl: Replace Diamond search with a BFS #6693
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Signed-off-by: Lucas Yuki Imamura <[email protected]>
Signed-off-by: Lucas Yuki Imamura <[email protected]>
Signed-off-by: LucasYuki <[email protected]>
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src/dpl/include/dpl/Opendp.h
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| int& best_dist) const; | ||
| PixelPt binSearch(GridX x, const Cell* cell, GridX bin_x, GridY bin_y) const; | ||
| PixelPt searchNearestSite(const Cell* cell, GridX x, GridY y) const; | ||
| int calcDist(const GridPt p0, const GridPt p1) const; |
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warning: parameter 'p0' is const-qualified in the function declaration; const-qualification of parameters only has an effect in function definitions [readability-avoid-const-params-in-decls]
| int calcDist(const GridPt p0, const GridPt p1) const; | |
| int calcDist(GridPt p0, const GridPt p1) const; |
src/dpl/include/dpl/Opendp.h
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| int& best_dist) const; | ||
| PixelPt binSearch(GridX x, const Cell* cell, GridX bin_x, GridY bin_y) const; | ||
| PixelPt searchNearestSite(const Cell* cell, GridX x, GridY y) const; | ||
| int calcDist(const GridPt p0, const GridPt p1) const; |
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warning: parameter 'p1' is const-qualified in the function declaration; const-qualification of parameters only has an effect in function definitions [readability-avoid-const-params-in-decls]
| int calcDist(const GridPt p0, const GridPt p1) const; | |
| int calcDist(const GridPt p0, GridPt p1) const; |
src/dpl/include/dpl/Opendp.h
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| PixelPt searchNearestSite(const Cell* cell, GridX x, GridY y) const; | ||
| int calcDist(const GridPt p0, const GridPt p1) const; | ||
| bool canBePlaced(const Cell* cell, | ||
| const GridX bin_x, |
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warning: parameter 'bin_x' is const-qualified in the function declaration; const-qualification of parameters only has an effect in function definitions [readability-avoid-const-params-in-decls]
| const GridX bin_x, | |
| GridX bin_x, |
src/dpl/include/dpl/Opendp.h
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| int calcDist(const GridPt p0, const GridPt p1) const; | ||
| bool canBePlaced(const Cell* cell, | ||
| const GridX bin_x, | ||
| const GridY bin_y) const; |
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warning: parameter 'bin_y' is const-qualified in the function declaration; const-qualification of parameters only has an effect in function definitions [readability-avoid-const-params-in-decls]
| const GridY bin_y) const; | |
| GridY bin_y) const; |
Signed-off-by: Lucas Yuki Imamura <[email protected]>
Signed-off-by: Lucas Yuki Imamura <[email protected]>
| @@ -248,4 +250,15 @@ struct hash<dpl::TypedCoordinate<T>> | |||
| } | |||
| }; | |||
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This weakens the type checking. Is it needed?
| std::unordered_set<GridPt> inQueuePositions; | ||
| GridPt center{x, y}; | ||
| positionsHeap.push(PQ_entry{0, center}); | ||
| inQueuePositions.insert(center); |
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When a point is popped from the heap it is not removed from inQueuePositions. It therefore is misleadingly named as you can be in inQueuePositions but not actually be queued. I think visited would be clearer.
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Some small comments but generally fine. Waiting on CI and conflict resolution. |
Signed-off-by: LucasYuki <[email protected]>
Replaces Diamond Search with a BFS to minimize single cell displacement.
The diamond search finds the closest free site to place a cell, but the distance was measured in sites.
Now the search finds the closest free site measured in dbu.
Since only the displacement of individual cells is optimized, this doesn't mean that the total displacement is always reduced compared to the current diamond search.
There are test cases where the total displacement increases, but in most cases, the total displacement is smaller than before.