Projects

Jan. 2024 - Present
Document

Designed a dataflow-centric typing system and intermediate representation (IR) to model the kernel processing and communication at tensor level in MLIR.
Introduced stream-based kernel fusion, on-the-fly memory layout conversion, and dataflow FIFO optimization to reduce off-chip memory access and on-chip memory size.
Designed a compilation pipeline that compiles PyTorch model, e.g., large language model (LLM), to low-level IRs targeting dataflow accelerators, such as AMD Versal ACAP and FPGA.

May. 2023 - Aug. 2023
Document / GitHub

XLS implements a High-level Synthesis (HLS) toolchain which produces synthesizable designs (Verilog and SystemVerilog) from flexible, high-level descriptions of functionality.
Proposed a feedback-directed optimization (FDO) method named ISDC that takes downstream tools, e.g., OpenROAD, results as feedback to improve SDC scheduling quality of HLS.
Achieved a 28.5% lower register usage compared to the original SDC scheduling on SKY130.

Mar. 2022 - Jan. 2024
GitHub

Proposed a hierarchical dataflow intermediate representation (IR) to model and optimize the complicated dataflow structures in High-level Synthesis (HLS).
Designed an algorithm to guide the local design space exploration of each dataflow node while keeping the global dataflow balanced and efficient.

Dec. 2021 - Oct. 2022
GitHub

Mapped GEMM-based models, e.g., BERT and ViT, to accelerators on AMD Versal ACAP; Non-GEMM kernels and data movement kernels are implemented on Programming Logic (PL).
Proposed a design space exploration algorithm to determine the tiling strategy at each level of memory.

Oct. 2021 - Apr. 2022
GitHub

Designed a compilation flow from C/C++ programs to the AI-Engine (AIE) array on AMD Versal ACAP using Polyhedral compilation techniques in MLIR.

Jun. 2020 - Oct. 2021
Document / GitHub

The CIRCT open-source project is an effort looking to apply MLIR and the LLVM development methodology to the domain of hardware design tools.
Contributed to the FIRRTL, HW (Hardware), and SV (SystemVerilog) dialects and transformations to establish the hardware 'core IR' of CIRCT and enable a Chisel to SystemVerilog compilation flow.
Contributed a new FSM dialect to represent, optimize, and generate codes for finite-state machines.
Contributed to the Handshake and Pipeline dialects to enable a High-level Synthesis (HLS) flow that compiles the 'core IR' of MLIR to the hardware 'core IR' of CIRCT.

Apr. 2020 - Mar. 2022
GitHub

Designed a multi-level HLS representation and optimization framework in MLIR.
Designed an HLS-specific transform and analysis library, including loop and pragma optimizations, an HLS Quality-of-Result (QoR) estimator, and a multi-objective design space explorer.
Designed a C/C++ front-end and an HLS C/C++ code generator for MLIR.

Feb. 2020 - Mar. 2021

Proposed a novel DNN acceleration paradigm which can take advantage of both dataflow pipeline and overlay architectures, enabling a more scalable solution compared to previous arts.
Proposed an efficient design space exploration algorithm to generate optimized DNN accelerators following the new paradigm.

Jan. 2019 - Dec. 2019

Proposed a hybrid Spatial and Winograd convolution architecture for DNN acceleration.
Designed a comprehensive tool for the performance and area estimation and the design space exploration for both edge and cloud FPGAs.

Apr. 2018 - Aug. 2018

Pruned and transplanted a RISCV core to an edge FPGA and established a low-power SoC.
Ported an RTOS to manage sensors and the wireless connection between FPGA and smartphones.
Won the outstanding award of the 2nd China College IC Competition.

Oct. 2017 - May. 2018

Proposed a Dynamic Partial Reconfiguration (DPR) -based pipeline architecture to deploy large CNN accelerators on resource-limited FPGAs while maintaining a low overall latency.