In the past decade, computer systems and chips have played a key role in the success of AI. Our vision in Google Brain's ML for Systems team is to use AI to transform the way systems and chips are designed. Many core problems in systems and hardware design are combinatorial optimization or decision making tasks with state and actions sizes that are orders of magnitude larger than common AI benchmarks in robotics and games. In this talk, we will go over some of our research on tackling such optimization problems. First, we talk about our work on deep reinforcement learning models that learn to do computational resource allocation, a combinatorial optimization problem that repeatedly appears in systems. Our method is end-to-end and abstracts away the complexity of the underlying optimization space; the RL agent learns the implicit tradeoffs between computation and communication of the underlying resources and optimizes the allocation using only the true reward function (e.g., the runtime of the generated allocation). We will then discuss our work on optimizing chip placement with reinforcement learning. Our approach has the ability to learn from past experience and improve over time. To enable our RL policy to generalize to unseen blocks. Our objective is to minimize PPA (power, performance, and area), and we show that, in under 6 hours, our method can generate placements that are superhuman or comparable on modern accelerator chips, whereas existing baselines require human experts in the loop and can take several weeks.
In this talk, I will give an overview of our recent efforts leveraging modern AI advancement with domain-specific customizations for agile IC physical design and manufacturing closure. I will first show how we leverage deep learning hardware and software to develop a new open-source VLSI placement engine, DREAMPlace [DAC’19], which is over 30x faster than the previous SOTA academic placer with similar quality of results. I will then present MAGICAL (Machine Generated Analog IC Layout) system, funded by the DARPA IDEA program to produce fully automated, no-human-in-the-loop analog layouts from netlists to GDSII with very promising results [ICCAD’19]. I will further show how we leverage recent AI breakthrough in generative adversarial network (GAN) to develop end-to-end lithography modeling with orders of magnitude speedup [DAC’19, ISPD’20]. The closed-loop between AI and IC will be discussed.
The wave of machine learning splashes to almost every corner of the world and EDA is no exception.
Indeed, machine learning brings significant improvement over conventional EDA in various places.
On the other hand, the applications of machine learning tend to be straightforward plug-in use, largely
due to the poor explicability of many ML techniques. Nevertheless, we believe that the merit of ML EDA research
hinges on deep interactions with domain knowledge and customizations wherever possible. To this end,
two examples of such endeavor are presented. One is on functional verification acceleration and the other
is design rule violation prediction.
I will talk about Once-for-All network for efficient neural architecture search. Conventional NAS methods are computationally prohibitive (causing
CO2 emission as much as 5 cars’ lifetime) thus unscalable. In this work, we propose to train a Once-for-All Network (OFA, ICLR’20) that can specialize for different hardware platforms without retraining. It consistently outperforms state-of-the-art NAS methods including MobileNet-v3 and EfficientNet, while reducing many orders of magnitude GPU hours and CO2 emission, receiving the 1st place in the 3rd and 4th Low Power Computer Vision Challenge (LPCVC). I will also talk about ProxylessNAS that received the 1st place in the Google Visual Wake Works challenge and has been integrated by the research community including PyTorch and AutoGluon.
With the development of advanced process nodes of semiconductor, the problem of pin access has become one of the major factors to impact the occurrences of design rule violations (DRVs) due to complex design rules and limited routing resource. To tackle this problem, many recent works apply machine learning-based techniques to predict whether a local region has DRV or not by regarding global routing (GR) congestion and local pin density as the main features during the training process. Empirically, however, DRV occurrence is not necessary to be strongly correlated with the two features in advanced nodes. In this talk, I will present two of our works on DRV prediction using pin patterns as the major feature and model-guided placement refinement for DRV reduction [DAC’19, ISPD’20].