As Very Large Scale Integration (VLSI) designs continue to scale in size and complexity, layout verification has become a central challenge in modern Electronic Design Automation (EDA) workflows. In practice, congestion can only be accurately identified after detailed routing, making traditional verification both time-consuming and costly. Learning-based approaches have therefore been explored to enable early-stage congestion prediction and reduce routing iterations. However, although prior methods incorporate both netlist connectivity and layout features, they often model the two in a loosely coupled manner and primarily produce numerical congestion estimates. We propose VeriHGN, a verification framework built on an enhanced heterogeneous graph that unifies circuit components and spatial grids into a single relational representation, enabling more faithful modeling of the interaction between logical intent and physical realization. Experiments on industrial benchmarks, including ISPD2015, CircuitNet-N14, and CircuitNet-N28, demonstrate that VeriHGN achieves the best or near-best performance over state-of-the-art methods in prediction accuracy and correlation metrics.
Figures & tables
Figure 1. Example of routing congestion formation in a placement–routing workflow. (a): multiple logic blocks are placed on the layout grid with interconnecting nets. (b): global routing paths overlap and compete for limited routing resources, creating localized routing congestion. (c): accumulated routing demand is visualized as a congestion map, where colors indicate congestion levels (low to high), and red regions highlight areas where routing demand exceeds available capacity.
Figure 2. Overview of VeriHGN graph construction. Starting from the original circuit design ( 1 ), we derive a hierarchical grid representation ( 2 ) for multi-level spatial structure, a netlist graph ( 3 ) for circuit connectivity, and a cell-to-grid relationship graph ( 4 ) for spatial assignment. These components are integrated into a unified heterogeneous graph ( 5 ), enabling joint structural and spatial message passing.
Figure 3. Relation-based message passing. Messages are propagated along different relation types (cell–net, grid–net, geom–cell, and cell–grid) using relation-specific MLPs, enabling information exchange across circuit components and spatial grids.
Figure 4. Hierarchical grid representation learning. Grid features are aggregated from fine to coarse levels and then propagated back from coarse to fine levels, enabling multi-scale spatial information exchange.
Figure 5. Embedding and readout. Embeddings from different node types (cell, geom, net, and grid) are concatenated and mapped through a readout layer to produce the final congestion heatmap.
Dataset
Tech.
#Designs
#Cells
#Nets
#Samples
ISPD 2015
–
20
100K–1.2M
100K–1.3M
533
CircuitNet-N28
28nm
10
35K–1.5M
38K–1.6M
∼ 3K
CircuitNet-N14
14nm
8
35K–1.5M
38K–1.6M
∼ 2K
Table 1. Summary of datasets used in our experiments.
Dataset
Model
Cell-level
Grid-level
MAE ↓
RMSE ↓
Pearson ↑
Spearman ↑
Kendall ↑
MAE ↓
RMSE ↓
Pearson ↑
Spearman ↑
Kendall ↑
ISPD2015
GCN
0.041
0.047
0.347
0.398
0.321
0.038
0.049
0.299
0.273
0.163
GAT
0.039
0.045
0.361
0.385
0.337
0.036
0.046
0.304
0.273
0.179
CircuitGNN
0.034
0.040
0.598
0.322
0.217
0.042
0.049
0.364
0.162
0.134
MIHC
0.029
0.034
0.687
0.689
0.447
0.032
0.039
0.503
0.271
0.227
ST-FPN
0.039
0.043
0.533
0.332
0.290
0.037
0.041
0.483
0.375
0.208
Table 2. Overall comparison of cell-level and grid-level congestion prediction performance.
Cell-level
Grid-level
Remove Variant
MAE ↓
Spear. ↑
Kend. ↑
MAE ↓
Spear. ↑
Kend. ↑
None
0.037
0.548
0.414
0.034
0.401
0.308
Hierarchical Grid
0.039
0.511
0.383
0.038
0.342
0.261
Grid-Net MP
0.040
0.503
0.371
0.037
0.356
0.274
Geom. Cell–Cell MP
0.038
0.527
0.396
0.035
0.381
0.290
Gated Aggregation
0.038
0.531
0.399
0.035
0.387
0.295
Table 3. Ablation study on CircuitNet-N28. "None" denotes the complete VeriHGN model. Each row removes or replaces one component.
Figure 6. Sensitivity of VeriHGN to key hyperparameters on CircuitNet-N28: (a) number of message-passing layers L , (b) hidden dimension d , and (c) number of hierarchical grid levels K . Circles highlight the optimal configuration ( L=3 , d=128 , K=2 ).
Train → Test
Model
MAE ↓
Pears. ↑
Spear. ↑
Kend. ↑
Δρs
N14 → N14
MIHC
0.036
0.524
0.512
0.447
–
N14 → N14
VeriHGN
0.038
0.543
0.513
0.461
–
N28 → N28
MIHC
0.036
0.661
0.522
0.396
–
N28 → N28
VeriHGN
0.037
0.663
0.548
0.414
–
N28 → N14
MIHC
0.062
0.198
0.168
0.114
32.8%
N28 → N14
VeriHGN
0.056
0.261
0.224
0.159
43.7%
Table 4. Cross-design generalization (cell-level). Δρs denotes the relative Spearman retention under transfer: ρstransfer/ρsin-domain .
Transfer
0%
10%
30%
50%
70%
90%
Non-trans.
N28 → N14
0.224
0.330
0.400
0.490
0.500
0.510
0.513
N14 → N28
0.258
0.353
0.421
0.516
0.538
0.544
0.548
Table 5. Few-shot fine-tuning sensitivity under cross-design transfer. The reported metric is cell-level Spearman correlation.
Model
Dataset
GC (S,M,L) (s)
Train (min)
Epoch (s)
Inf. (s)
Mem. (GB)
CircuitGNN
ISPD2015
(8.0, 180.3, 286.4)
41.3
17.0
9.0
14.0
N14
(2.5, 160.7, 303.3)
180.3
18.0
13.3
21.0
N28
(2.7, 177.9, 300.0)
161.7
15.0
11.3
17.0
MIHC
ISPD2015
(2.8, 215.4, 678.6)
97.6
29.1
14.6
18.45
N14
(3.9, 283.5, 684.0)
928.6
300.2
7.3
28.56
N28
(3.7, 271.5, 584.0)
842.9
283.6
26.0
38.56
Table 6. Runtime and memory comparison across datasets.