We are happy to announce that Xplace 2.0 is now released. Comparing to [Xplace 1.0](https://dl.acm.org/doi/abs/10.1145/3489517.3530485), this version supports the following new features:
- Support deterministic mode with only 5~25% extra GP runtime overhead.
- Implement an extremly fast GPU-accelerated detailed-routability-driven placement algorithm.
- Integrate with a GPU-accelerated detailed placer and a GPU-accelerated global router.
- Provide benchmark download and preprocess scripts, and three routability evalution scripts.
- Code refactoring.
😄 Detailed Experimental results of Xplace 2.0 are given in [BENCHMARK.md](BENCHMARK.md).
## About
Xplace is a fast and extensible GPU accelerated global placement framework developed by the research team supervised by Prof. Evangeline F. Y. Young at The Chinese University of Hong Kong (CUHK). It achieves around 3x speedup per GP iteration compared to DREAMPlace and shows high extensiblity.
As shown in the following figure, Xplace framework is built on top of PyTorch and consists of serveral independent modules. One can easily extend Xplace by applying new scheduling techniques, new gradient functions, new placement metrics and so on.
Lixin Liu, Bangqi Fu, Martin D. F. Wong, and Evangeline F. Y. Young. "[Xplace: an extremely fast and extensible global placement framework](https://doi.org/10.1145/3489517.3530485)". In Proceedings of the 59th ACM/IEEE Design Automation Conference (DAC '22). Association for Computing Machinery, New York, NY, USA, 1309–1314.
(For the Xplace-NN, please refer to branch [neural](https://github.com/cuhk-eda/Xplace/tree/neural))
The following script will automatically download `ispd2005`, `ispd2015` and `iccad2019` in `./data/raw`. It also preprocesses `ispd2015` benchmark to fix some errors reported by Innovus.
**NOTE**: we defaultly enable the deterministic mode. If you don't need determinism and want to run placement in an extremely fast mode, please try to set `--deterministic False` in the python arguments.
- Each run will generate serveral output files in `./result/exp_id`. These files can provide valuable information for parameter tuning.
```
In ./result/exp_id
- eval # parameter curves and the visualization of placement
- log # log and statistics
- output # global placement solution files
```
## Parameters
Please refer to `main.py`.
## Load design from preprocessed `pt` file (Optional)
The following script will dump the parsed design into a single torch `pt` file so Xplace can load the design from the `pt` file instead of parsing the input file from scratch.
When developing a new global placement technique in Xplace, we highly suggest using the `pt` mode to save the parser time. (set `--load_from_raw False`)
1. Please remember to use the raw mode (set `--load_from_raw True`) when measuring the total running time.
2. We currently not support `pt` mode in routability-driven mode.
## Evaluate the Routability of Xplace's Solution
We provide three ways to evaluate the routability:
1. Set `--final_route_eval True` in python arguments to invoke the internal global router [GGR](https://dl.acm.org/doi/10.1145/3508352.3549474) to evaluate the placement solution. The evaluation metrics are reported in the log and recorded in `./result/exp_id/log/route.csv`. Besies, the route guide file is written in `./result/exp_id/output/design_name.guide` and
More details about using GGR in Xplace can be found in [cpp_to_py/gpugr](cpp_to_py/gpugr).
2. Use [CU-GR](https://github.com/cuhk-eda/cu-gr) to global route the placement solution. refer to [tool/cugr_ispd2015_fix](tool/cugr_ispd2015_fix) for more instructions.
3. (Optional). If Innovus® has been properly installed in your OS, you may try to use Innovus® to detailedly route the placement solution. Please refer to [tool/innovus_ispd2015_fix](tool/innovus_ispd2015_fix) for more instructions.
If you find **Xplace** useful in your research, please consider to cite:
```bibtex
@inproceedings{liu2022xplace,
author={Liu, Lixin and Fu, Bangqi and Wong, Martin D. F. and Young, Evangeline F. Y.},
booktitle={Proceedings of the 59th ACM/IEEE Design Automation Conference},
title={Xplace: An Extremely Fast and Extensible Global Placement Framework},
year={2022},
}
```
Thanks the authors of [ePlace](https://dl.acm.org/doi/10.1145/2699873), [RePlAce](https://github.com/The-OpenROAD-Project/RePlAce), and [DREAMPlace](https://github.com/limbo018/DREAMPlace) for their great work.
```bibtex
@article{lu2015eplace,
author={Lu, Jingwei and Chen, Pengwen and Chang, Chin-Chih and Sha, Lu and Huang, Dennis Jen-Hsin and Teng, Chin-Chi and Cheng, Chung-Kuan},
journal={ACM Trans. Des. Autom. Electron. Syst.},
title={ePlace: Electrostatics-Based Placement Using Fast Fourier Transform and Nesterov's Method},
year={2015},
}
@article{cheng2019replace,
author={Cheng, Chung-Kuan and Kahng, Andrew B. and Kang, Ilgweon and Wang, Lutong},
journal={IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems},
title={RePlAce: Advancing Solution Quality and Routability Validation in Global Placement},
year={2019},
}
@article{lin2021dreamplace,
author={Lin, Yibo and Jiang, Zixuan and Gu, Jiaqi and Li, Wuxi and Dhar, Shounak and Ren, Haoxing and Khailany, Brucek and Pan, David Z.},
journal={IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems},
title={DREAMPlace: Deep Learning Toolkit-Enabled GPU Acceleration for Modern VLSI Placement},