3D SB

[amin1377]

Description

This PR addresses an issue with the router lookahead when the architecture includes 3D switch blocks (SB). The issue arose from how the data structure, which contains the routing segments accessible from OPIN/SOURCE, was utilized. Previously, when calculating the cost from OPINs to SINKs, only the routing segments on the sink layer were considered. This approach worked when OPINs were connected directly to other layers. However, with 3D SBs, OPINs are not directly connected. Therefore, when calculating the OPIN cost to a sink on a different layer, routing segments on the same layer as the OPIN, which can still reach the sink, should also be considered.

To fix this, the cost calculation from OPIN to SINK now iterates over routing segments accessible from the OPIN across all layers, using the lowest cost found.

This PR also adds two additional tests specifically for scenarios with 3D SBs.

During debugging, I created a simple script to calculate the number of inter-die connections, and here is the count per tile for a small SIV architecture. @saaramahmoudi , it looks reasonable to me, but please let me know if you notice anything unusual.

******** 0->1 ******** ******** 1->0 ********
[1][0] -> 0 [1][0] -> 0
[1][1] -> 41 [1][1] -> 44
[1][2] -> 28 [1][2] -> 27
[1][3] -> 29 [1][3] -> 26
[1][4] -> 28 [1][4] -> 27
[1][5] -> 26 [1][5] -> 27
[1][6] -> 27 [1][6] -> 25
[1][7] -> 27 [1][7] -> 25
[1][8] -> 27 [1][8] -> 25
[1][9] -> 26 [1][9] -> 26
[1][10] -> 27 [1][10] -> 25
[1][11] -> 27 [1][11] -> 25
[1][12] -> 26 [1][12] -> 26
[1][13] -> 27 [1][13] -> 25
[1][14] -> 27 [1][14] -> 25
[1][15] -> 27 [1][15] -> 25
[1][16] -> 26 [1][16] -> 26
[1][17] -> 28 [1][17] -> 26
[1][18] -> 27 [1][18] -> 28
[1][19] -> 40 [1][19] -> 24
[2][0] -> 0 [2][0] -> 0
[2][1] -> 29 [2][1] -> 26
[2][2] -> 13 [2][2] -> 12
[2][3] -> 13 [2][3] -> 13
[2][4] -> 11 [2][4] -> 12
[2][5] -> 11 [2][5] -> 10
[2][6] -> 10 [2][6] -> 12
[2][7] -> 10 [2][7] -> 12
[2][8] -> 12 [2][8] -> 10
[2][9] -> 12 [2][9] -> 9
[2][10] -> 11 [2][10] -> 11
[2][11] -> 12 [2][11] -> 10
[2][12] -> 13 [2][12] -> 9
[2][13] -> 10 [2][13] -> 11
[2][14] -> 12 [2][14] -> 10
[2][15] -> 13 [2][15] -> 9
[2][16] -> 11 [2][16] -> 12
[2][17] -> 13 [2][17] -> 12
[2][18] -> 12 [2][18] -> 13
[2][19] -> 24 [2][19] -> 10
[3][0] -> 0 [3][0] -> 0
[3][1] -> 26 [3][1] -> 29
[3][2] -> 15 [3][2] -> 11
[3][3] -> 12 [3][3] -> 11
[3][4] -> 12 [3][4] -> 9
[3][5] -> 10 [3][5] -> 12
[3][6] -> 10 [3][6] -> 12
[3][7] -> 11 [3][7] -> 11
[3][8] -> 11 [3][8] -> 10
[3][9] -> 12 [3][9] -> 10
[3][10] -> 10 [3][10] -> 12
[3][11] -> 11 [3][11] -> 11
[3][12] -> 11 [3][12] -> 10
[3][13] -> 11 [3][13] -> 11
[3][14] -> 11 [3][14] -> 11
[3][15] -> 12 [3][15] -> 11
[3][16] -> 13 [3][16] -> 12
[3][17] -> 13 [3][17] -> 12
[3][18] -> 14 [3][18] -> 12
[3][19] -> 23 [3][19] -> 10
[4][0] -> 0 [4][0] -> 0
[4][1] -> 28 [4][1] -> 27
[4][2] -> 13 [4][2] -> 10
[4][3] -> 11 [4][3] -> 10
[4][4] -> 10 [4][4] -> 12
[4][5] -> 11 [4][5] -> 11
[4][6] -> 12 [4][6] -> 10
[4][7] -> 11 [4][7] -> 10
[4][8] -> 11 [4][8] -> 11
[4][9] -> 10 [4][9] -> 12
[4][10] -> 12 [4][10] -> 10
[4][11] -> 9 [4][11] -> 12
[4][12] -> 11 [4][12] -> 11
[4][13] -> 12 [4][13] -> 10
[4][14] -> 11 [4][14] -> 12
[4][15] -> 10 [4][15] -> 15
[4][16] -> 11 [4][16] -> 14
[4][17] -> 12 [4][17] -> 14
[4][18] -> 12 [4][18] -> 11
[4][19] -> 23 [4][19] -> 8
[5][0] -> 0 [5][0] -> 0
[5][1] -> 28 [5][1] -> 25
[5][2] -> 12 [5][2] -> 9
[5][3] -> 13 [5][3] -> 9
[5][4] -> 11 [5][4] -> 11
[5][5] -> 11 [5][5] -> 11
[5][6] -> 11 [5][6] -> 10
[5][7] -> 10 [5][7] -> 12
[5][8] -> 12 [5][8] -> 10
[5][9] -> 12 [5][9] -> 10
[5][10] -> 10 [5][10] -> 11
[5][11] -> 11 [5][11] -> 11
[5][12] -> 13 [5][12] -> 9
[5][13] -> 12 [5][13] -> 11
[5][14] -> 11 [5][14] -> 14
[5][15] -> 12 [5][15] -> 13
[5][16] -> 12 [5][16] -> 14
[5][17] -> 10 [5][17] -> 13
[5][18] -> 13 [5][18] -> 8
[5][19] -> 24 [5][19] -> 8
[6][0] -> 0 [6][0] -> 0
[6][1] -> 26 [6][1] -> 26
[6][2] -> 11 [6][2] -> 11
[6][3] -> 11 [6][3] -> 11
[6][4] -> 11 [6][4] -> 11
[6][5] -> 11 [6][5] -> 10
[6][6] -> 10 [6][6] -> 12
[6][7] -> 10 [6][7] -> 12
[6][8] -> 11 [6][8] -> 11
[6][9] -> 11 [6][9] -> 10
[6][10] -> 10 [6][10] -> 12
[6][11] -> 11 [6][11] -> 11
[6][12] -> 12 [6][12] -> 11
[6][13] -> 12 [6][13] -> 13
[6][14] -> 12 [6][14] -> 13
[6][15] -> 11 [6][15] -> 15
[6][16] -> 11 [6][16] -> 12
[6][17] -> 10 [6][17] -> 11
[6][18] -> 11 [6][18] -> 11
[6][19] -> 25 [6][19] -> 7
[7][0] -> 0 [7][0] -> 0
[7][1] -> 27 [7][1] -> 25
[7][2] -> 12 [7][2] -> 10
[7][3] -> 13 [7][3] -> 9
[7][4] -> 12 [7][4] -> 9
[7][5] -> 11 [7][5] -> 11
[7][6] -> 11 [7][6] -> 11
[7][7] -> 13 [7][7] -> 9
[7][8] -> 12 [7][8] -> 9
[7][9] -> 11 [7][9] -> 11
[7][10] -> 12 [7][10] -> 10
[7][11] -> 11 [7][11] -> 12
[7][12] -> 14 [7][12] -> 11
[7][13] -> 13 [7][13] -> 12
[7][14] -> 11 [7][14] -> 15
[7][15] -> 11 [7][15] -> 12
[7][16] -> 9 [7][16] -> 12
[7][17] -> 10 [7][17] -> 12
[7][18] -> 13 [7][18] -> 9
[7][19] -> 23 [7][19] -> 9
[8][0] -> 0 [8][0] -> 0
[8][1] -> 28 [8][1] -> 24
[8][2] -> 12 [8][2] -> 10
[8][3] -> 11 [8][3] -> 10
[8][4] -> 11 [8][4] -> 11
[8][5] -> 12 [8][5] -> 10
[8][6] -> 10 [8][6] -> 12
[8][7] -> 10 [8][7] -> 11
[8][8] -> 12 [8][8] -> 10
[8][9] -> 12 [8][9] -> 10
[8][10] -> 12 [8][10] -> 11
[8][11] -> 11 [8][11] -> 14
[8][12] -> 13 [8][12] -> 12
[8][13] -> 13 [8][13] -> 13
[8][14] -> 11 [8][14] -> 12
[8][15] -> 9 [8][15] -> 12
[8][16] -> 14 [8][16] -> 8
[8][17] -> 10 [8][17] -> 12
[8][18] -> 11 [8][18] -> 11
[8][19] -> 23 [8][19] -> 8
[9][0] -> 0 [9][0] -> 0
[9][1] -> 27 [9][1] -> 25
[9][2] -> 11 [9][2] -> 10
[9][3] -> 10 [9][3] -> 12
[9][4] -> 12 [9][4] -> 10
[9][5] -> 12 [9][5] -> 10
[9][6] -> 12 [9][6] -> 9
[9][7] -> 10 [9][7] -> 12
[9][8] -> 11 [9][8] -> 11
[9][9] -> 12 [9][9] -> 11
[9][10] -> 13 [9][10] -> 12
[9][11] -> 11 [9][11] -> 14
[9][12] -> 11 [9][12] -> 15
[9][13] -> 13 [9][13] -> 10
[9][14] -> 12 [9][14] -> 9
[9][15] -> 12 [9][15] -> 10
[9][16] -> 12 [9][16] -> 10
[9][17] -> 10 [9][17] -> 12
[9][18] -> 12 [9][18] -> 9
[9][19] -> 23 [9][19] -> 9
[10][0] -> 0 [10][0] -> 0
[10][1] -> 27 [10][1] -> 25
[10][2] -> 10 [10][2] -> 12
[10][3] -> 12 [10][3] -> 10
[10][4] -> 13 [10][4] -> 9
[10][5] -> 12 [10][5] -> 9
[10][6] -> 11 [10][6] -> 11
[10][7] -> 13 [10][7] -> 9
[10][8] -> 10 [10][8] -> 13
[10][9] -> 13 [10][9] -> 12
[10][10] -> 13 [10][10] -> 12
[10][11] -> 13 [10][11] -> 13
[10][12] -> 12 [10][12] -> 11
[10][13] -> 12 [10][13] -> 9
[10][14] -> 12 [10][14] -> 10
[10][15] -> 12 [10][15] -> 10
[10][16] -> 11 [10][16] -> 11
[10][17] -> 11 [10][17] -> 10
[10][18] -> 10 [10][18] -> 12
[10][19] -> 23 [10][19] -> 9
[11][0] -> 0 [11][0] -> 0
[11][1] -> 26 [11][1] -> 26
[11][2] -> 13 [11][2] -> 9
[11][3] -> 13 [11][3] -> 9
[11][4] -> 11 [11][4] -> 10
[11][5] -> 11 [11][5] -> 11
[11][6] -> 11 [11][6] -> 11
[11][7] -> 13 [11][7] -> 10
[11][8] -> 12 [11][8] -> 13
[11][9] -> 14 [11][9] -> 11
[11][10] -> 14 [11][10] -> 12
[11][11] -> 11 [11][11] -> 12
[11][12] -> 11 [11][12] -> 10
[11][13] -> 13 [11][13] -> 9
[11][14] -> 12 [11][14] -> 10
[11][15] -> 11 [11][15] -> 11
[11][16] -> 12 [11][16] -> 9
[11][17] -> 12 [11][17] -> 10
[11][18] -> 11 [11][18] -> 11
[11][19] -> 23 [11][19] -> 9
[12][0] -> 0 [12][0] -> 0
[12][1] -> 28 [12][1] -> 24
[12][2] -> 12 [12][2] -> 10
[12][3] -> 11 [12][3] -> 10
[12][4] -> 12 [12][4] -> 10
[12][5] -> 11 [12][5] -> 11
[12][6] -> 11 [12][6] -> 12
[12][7] -> 15 [12][7] -> 10
[12][8] -> 13 [12][8] -> 12
[12][9] -> 12 [12][9] -> 14
[12][10] -> 14 [12][10] -> 9
[12][11] -> 11 [12][11] -> 10
[12][12] -> 12 [12][12] -> 10
[12][13] -> 13 [12][13] -> 9
[12][14] -> 12 [12][14] -> 10
[12][15] -> 12 [12][15] -> 9
[12][16] -> 13 [12][16] -> 9
[12][17] -> 10 [12][17] -> 12
[12][18] -> 13 [12][18] -> 9
[12][19] -> 24 [12][19] -> 7
[13][0] -> 0 [13][0] -> 0
[13][1] -> 27 [13][1] -> 25
[13][2] -> 11 [13][2] -> 10
[13][3] -> 11 [13][3] -> 11
[13][4] -> 10 [13][4] -> 12
[13][5] -> 12 [13][5] -> 11
[13][6] -> 12 [13][6] -> 13
[13][7] -> 12 [13][7] -> 13
[13][8] -> 11 [13][8] -> 15
[13][9] -> 12 [13][9] -> 11
[13][10] -> 13 [13][10] -> 8
[13][11] -> 10 [13][11] -> 12
[13][12] -> 12 [13][12] -> 10
[13][13] -> 11 [13][13] -> 11
[13][14] -> 12 [13][14] -> 9
[13][15] -> 12 [13][15] -> 10
[13][16] -> 12 [13][16] -> 10
[13][17] -> 10 [13][17] -> 12
[13][18] -> 12 [13][18] -> 9
[13][19] -> 24 [13][19] -> 8
[14][0] -> 0 [14][0] -> 0
[14][1] -> 26 [14][1] -> 26
[14][2] -> 11 [14][2] -> 11
[14][3] -> 11 [14][3] -> 11
[14][4] -> 13 [14][4] -> 10
[14][5] -> 14 [14][5] -> 11
[14][6] -> 13 [14][6] -> 12
[14][7] -> 11 [14][7] -> 15
[14][8] -> 11 [14][8] -> 12
[14][9] -> 12 [14][9] -> 9
[14][10] -> 11 [14][10] -> 11
[14][11] -> 10 [14][11] -> 12
[14][12] -> 11 [14][12] -> 11
[14][13] -> 11 [14][13] -> 10
[14][14] -> 10 [14][14] -> 12
[14][15] -> 10 [14][15] -> 12
[14][16] -> 11 [14][16] -> 11
[14][17] -> 11 [14][17] -> 10
[14][18] -> 12 [14][18] -> 10
[14][19] -> 24 [14][19] -> 8
[15][0] -> 0 [15][0] -> 0
[15][1] -> 27 [15][1] -> 25
[15][2] -> 12 [15][2] -> 10
[15][3] -> 12 [15][3] -> 11
[15][4] -> 14 [15][4] -> 11
[15][5] -> 11 [15][5] -> 14
[15][6] -> 13 [15][6] -> 13
[15][7] -> 12 [15][7] -> 11
[15][8] -> 11 [15][8] -> 10
[15][9] -> 11 [15][9] -> 11
[15][10] -> 10 [15][10] -> 12
[15][11] -> 12 [15][11] -> 10
[15][12] -> 12 [15][12] -> 9
[15][13] -> 11 [15][13] -> 11
[15][14] -> 11 [15][14] -> 11
[15][15] -> 11 [15][15] -> 11
[15][16] -> 12 [15][16] -> 9
[15][17] -> 13 [15][17] -> 9
[15][18] -> 11 [15][18] -> 11
[15][19] -> 26 [15][19] -> 7
[16][0] -> 0 [16][0] -> 0
[16][1] -> 26 [16][1] -> 26
[16][2] -> 12 [16][2] -> 11
[16][3] -> 13 [16][3] -> 12
[16][4] -> 10 [16][4] -> 15
[16][5] -> 13 [16][5] -> 13
[16][6] -> 11 [16][6] -> 12
[16][7] -> 12 [16][7] -> 9
[16][8] -> 11 [16][8] -> 11
[16][9] -> 12 [16][9] -> 10
[16][10] -> 12 [16][10] -> 10
[16][11] -> 11 [16][11] -> 10
[16][12] -> 11 [16][12] -> 11
[16][13] -> 11 [16][13] -> 11
[16][14] -> 11 [16][14] -> 11
[16][15] -> 13 [16][15] -> 8
[16][16] -> 11 [16][16] -> 11
[16][17] -> 12 [16][17] -> 10
[16][18] -> 13 [16][18] -> 10
[16][19] -> 25 [16][19] -> 9
[17][0] -> 0 [17][0] -> 0
[17][1] -> 26 [17][1] -> 28
[17][2] -> 15 [17][2] -> 10
[17][3] -> 12 [17][3] -> 13
[17][4] -> 13 [17][4] -> 13
[17][5] -> 10 [17][5] -> 13
[17][6] -> 12 [17][6] -> 9
[17][7] -> 13 [17][7] -> 9
[17][8] -> 12 [17][8] -> 10
[17][9] -> 11 [17][9] -> 11
[17][10] -> 11 [17][10] -> 10
[17][11] -> 11 [17][11] -> 11
[17][12] -> 12 [17][12] -> 10
[17][13] -> 11 [17][13] -> 11
[17][14] -> 11 [17][14] -> 10
[17][15] -> 12 [17][15] -> 10
[17][16] -> 13 [17][16] -> 9
[17][17] -> 11 [17][17] -> 12
[17][18] -> 13 [17][18] -> 12
[17][19] -> 23 [17][19] -> 11
[18][0] -> 0 [18][0] -> 0
[18][1] -> 27 [18][1] -> 28
[18][2] -> 13 [18][2] -> 12
[18][3] -> 12 [18][3] -> 14
[18][4] -> 10 [18][4] -> 13
[18][5] -> 12 [18][5] -> 9
[18][6] -> 11 [18][6] -> 11
[18][7] -> 12 [18][7] -> 10
[18][8] -> 10 [18][8] -> 12
[18][9] -> 11 [18][9] -> 10
[18][10] -> 10 [18][10] -> 12
[18][11] -> 11 [18][11] -> 11
[18][12] -> 10 [18][12] -> 12
[18][13] -> 13 [18][13] -> 8
[18][14] -> 11 [18][14] -> 11
[18][15] -> 13 [18][15] -> 9
[18][16] -> 13 [18][16] -> 10
[18][17] -> 13 [18][17] -> 12
[18][18] -> 12 [18][18] -> 13
[18][19] -> 25 [18][19] -> 9
[19][0] -> 0 [19][0] -> 0
[19][1] -> 26 [19][1] -> 29
[19][2] -> 12 [19][2] -> 14
[19][3] -> 13 [19][3] -> 10
[19][4] -> 13 [19][4] -> 8
[19][5] -> 12 [19][5] -> 10
[19][6] -> 12 [19][6] -> 10
[19][7] -> 12 [19][7] -> 10
[19][8] -> 10 [19][8] -> 11
[19][9] -> 10 [19][9] -> 12
[19][10] -> 11 [19][10] -> 11
[19][11] -> 13 [19][11] -> 9
[19][12] -> 11 [19][12] -> 10
[19][13] -> 11 [19][13] -> 11
[19][14] -> 11 [19][14] -> 11
[19][15] -> 11 [19][15] -> 12
[19][16] -> 11 [19][16] -> 14
[19][17] -> 12 [19][17] -> 13
[19][18] -> 13 [19][18] -> 13
[19][19] -> 24 [19][19] -> 9
[20][0] -> 0 [20][0] -> 0
[20][1] -> 28 [20][1] -> 27
[20][2] -> 11 [20][2] -> 12
[20][3] -> 12 [20][3] -> 9
[20][4] -> 13 [20][4] -> 9
[20][5] -> 13 [20][5] -> 9
[20][6] -> 11 [20][6] -> 11
[20][7] -> 10 [20][7] -> 11
[20][8] -> 12 [20][8] -> 10
[20][9] -> 9 [20][9] -> 13
[20][10] -> 10 [20][10] -> 12
[20][11] -> 10 [20][11] -> 11
[20][12] -> 12 [20][12] -> 10
[20][13] -> 13 [20][13] -> 9
[20][14] -> 11 [20][14] -> 12
[20][15] -> 14 [20][15] -> 11
[20][16] -> 14 [20][16] -> 11
[20][17] -> 12 [20][17] -> 14
[20][18] -> 12 [20][18] -> 11
[20][19] -> 23 [20][19] -> 8
[21][0] -> 0 [21][0] -> 0
[21][1] -> 26 [21][1] -> 27
[21][2] -> 12 [21][2] -> 9
[21][3] -> 11 [21][3] -> 11
[21][4] -> 14 [21][4] -> 8
[21][5] -> 11 [21][5] -> 11
[21][6] -> 12 [21][6] -> 9
[21][7] -> 11 [21][7] -> 11
[21][8] -> 11 [21][8] -> 11
[21][9] -> 10 [21][9] -> 12
[21][10] -> 11 [21][10] -> 10
[21][11] -> 11 [21][11] -> 11
[21][12] -> 11 [21][12] -> 11
[21][13] -> 13 [21][13] -> 10
[21][14] -> 12 [21][14] -> 13
[21][15] -> 12 [21][15] -> 13
[21][16] -> 14 [21][16] -> 12
[21][17] -> 12 [21][17] -> 11
[21][18] -> 11 [21][18] -> 10
[21][19] -> 23 [21][19] -> 9
[22][0] -> 0 [22][0] -> 0
[22][1] -> 27 [22][1] -> 25
[22][2] -> 11 [22][2] -> 11
[22][3] -> 11 [22][3] -> 11
[22][4] -> 11 [22][4] -> 11
[22][5] -> 12 [22][5] -> 9
[22][6] -> 10 [22][6] -> 12
[22][7] -> 13 [22][7] -> 9
[22][8] -> 11 [22][8] -> 11
[22][9] -> 11 [22][9] -> 10
[22][10] -> 11 [22][10] -> 11
[22][11] -> 13 [22][11] -> 9
[22][12] -> 13 [22][12] -> 10
[22][13] -> 11 [22][13] -> 14
[22][14] -> 16 [22][14] -> 9
[22][15] -> 13 [22][15] -> 13
[22][16] -> 12 [22][16] -> 11
[22][17] -> 12 [22][17] -> 9
[22][18] -> 12 [22][18] -> 10
[22][19] -> 24 [22][19] -> 8
[23][0] -> 0 [23][0] -> 0
[23][1] -> 26 [23][1] -> 26
[23][2] -> 11 [23][2] -> 11
[23][3] -> 11 [23][3] -> 11
[23][4] -> 11 [23][4] -> 10
[23][5] -> 10 [23][5] -> 12
[23][6] -> 11 [23][6] -> 11
[23][7] -> 11 [23][7] -> 11
[23][8] -> 12 [23][8] -> 9
[23][9] -> 13 [23][9] -> 9
[23][10] -> 11 [23][10] -> 11
[23][11] -> 12 [23][11] -> 11
[23][12] -> 12 [23][12] -> 13
[23][13] -> 12 [23][13] -> 13
[23][14] -> 12 [23][14] -> 14
[23][15] -> 13 [23][15] -> 10
[23][16] -> 9 [23][16] -> 12
[23][17] -> 12 [23][17] -> 10
[23][18] -> 12 [23][18] -> 10
[23][19] -> 23 [23][19] -> 9
[24][0] -> 0 [24][0] -> 0
[24][1] -> 27 [24][1] -> 25
[24][2] -> 12 [24][2] -> 10
[24][3] -> 12 [24][3] -> 9
[24][4] -> 11 [24][4] -> 11
[24][5] -> 12 [24][5] -> 10
[24][6] -> 11 [24][6] -> 11
[24][7] -> 10 [24][7] -> 11
[24][8] -> 12 [24][8] -> 10
[24][9] -> 10 [24][9] -> 12
[24][10] -> 12 [24][10] -> 11
[24][11] -> 14 [24][11] -> 11
[24][12] -> 12 [24][12] -> 13
[24][13] -> 12 [24][13] -> 14
[24][14] -> 12 [24][14] -> 11
[24][15] -> 10 [24][15] -> 11
[24][16] -> 10 [24][16] -> 12
[24][17] -> 11 [24][17] -> 11
[24][18] -> 12 [24][18] -> 10
[24][19] -> 23 [24][19] -> 8
[25][0] -> 0 [25][0] -> 0
[25][1] -> 27 [25][1] -> 25
[25][2] -> 11 [25][2] -> 10
[25][3] -> 11 [25][3] -> 11
[25][4] -> 11 [25][4] -> 11
[25][5] -> 12 [25][5] -> 10
[25][6] -> 11 [25][6] -> 10
[25][7] -> 11 [25][7] -> 11
[25][8] -> 11 [25][8] -> 11
[25][9] -> 10 [25][9] -> 13
[25][10] -> 12 [25][10] -> 13
[25][11] -> 12 [25][11] -> 13
[25][12] -> 12 [25][12] -> 14
[25][13] -> 11 [25][13] -> 12
[25][14] -> 12 [25][14] -> 9
[25][15] -> 10 [25][15] -> 12
[25][16] -> 11 [25][16] -> 11
[25][17] -> 12 [25][17] -> 10
[25][18] -> 13 [25][18] -> 8
[25][19] -> 23 [25][19] -> 9
[26][0] -> 0 [26][0] -> 0
[26][1] -> 27 [26][1] -> 25
[26][2] -> 10 [26][2] -> 12
[26][3] -> 12 [26][3] -> 10
[26][4] -> 12 [26][4] -> 10
[26][5] -> 10 [26][5] -> 11
[26][6] -> 12 [26][6] -> 10
[26][7] -> 11 [26][7] -> 11
[26][8] -> 12 [26][8] -> 11
[26][9] -> 13 [26][9] -> 12
[26][10] -> 12 [26][10] -> 13
[26][11] -> 14 [26][11] -> 12
[26][12] -> 10 [26][12] -> 13
[26][13] -> 10 [26][13] -> 11
[26][14] -> 11 [26][14] -> 11
[26][15] -> 11 [26][15] -> 11
[26][16] -> 11 [26][16] -> 11
[26][17] -> 11 [26][17] -> 10
[26][18] -> 10 [26][18] -> 12
[26][19] -> 24 [26][19] -> 8
[27][0] -> 0 [27][0] -> 0
[27][1] -> 40 [27][1] -> 53
[27][2] -> 23 [27][2] -> 39
[27][3] -> 28 [27][3] -> 34
[27][4] -> 24 [27][4] -> 38
[27][5] -> 25 [27][5] -> 37
[27][6] -> 22 [27][6] -> 40
[27][7] -> 26 [27][7] -> 37
[27][8] -> 24 [27][8] -> 40
[27][9] -> 30 [27][9] -> 34
[27][10] -> 29 [27][10] -> 35
[27][11] -> 24 [27][11] -> 39
[27][12] -> 26 [27][12] -> 36
[27][13] -> 28 [27][13] -> 34
[27][14] -> 24 [27][14] -> 38
[27][15] -> 28 [27][15] -> 34
[27][16] -> 25 [27][16] -> 37
[27][17] -> 25 [27][17] -> 37
[27][18] -> 24 [27][18] -> 38
[27][19] -> 41 [27][19] -> 31

[vaughnbetz]

QoR data looks good (2D unchanged, 3D cube BB is better than per layer as expected, and 3D switch block circuits now route whereas they didn't before). Data at https://www.eecg.utoronto.ca/~vaughn/vaughnwiki/doku.php?id=amin_weekly_update
@amin1377 : please directly link to the QoR data or paste it here too.

[vaughnbetz]

A few suggested commenting changes, plus please link the QoR data directly.

[amin1377]

@vaughnbetz, I applied your comments, and I think the PR is ready to be merged.