Multi-level Coarsening Algorithm Perform Edge Coarsening (EC) Visit - - PowerPoint PPT Presentation

Practical Problems in VLSI Physical Design Multi-level Coarsening (1/11)

Perform Edge Coarsening (EC)

Visit nodes and break ties in alphabetical order Explicit clique-based graph model is not necessary

Multi-level Coarsening Algorithm

Practical Problems in VLSI Physical Design Multi-level Coarsening (2/11)

Edge Coarsening

Practical Problems in VLSI Physical Design Multi-level Coarsening (3/11)

Edge Coarsening (cont)

Practical Problems in VLSI Physical Design Multi-level Coarsening (4/11)

Obtaining Clustered-level Netlist

# of nodes/hyperedges reduced: 4 nodes, 5 hyperedges

Practical Problems in VLSI Physical Design Multi-level Coarsening (5/11)

Hyperedge Coarsening

Initial setup

Sort hyper-edges in increasing size: n4, n5, n1, n2, n3, n6 Unmark all nodes

Practical Problems in VLSI Physical Design Multi-level Coarsening (6/11)

Hyperedge Coarsening

Practical Problems in VLSI Physical Design Multi-level Coarsening (7/11)

Hyperedge Coarsening

Practical Problems in VLSI Physical Design Multi-level Coarsening (8/11)

Obtaining Clustered-level Netlist

# of nodes/hyperedges reduced: 6 nodes, 4 hyperedges

Practical Problems in VLSI Physical Design Multi-level Coarsening (9/11)

Modified Hyperedge Coarsening

Revisit skipped nets during hyperedge coarsening

We skipped n1, n2, n3, n6 Coarsen un-coarsened nodes in each net

Practical Problems in VLSI Physical Design Multi-level Coarsening (10/11)

Modified Hyperedge Coarsening

Practical Problems in VLSI Physical Design Multi-level Coarsening (11/11)

Obtaining Clustered-level Netlist

# of nodes/hyperedges reduced: 5 nodes, 4 hyperedges