Research using Tensilica's Technology

Current Research

The synthesis algorithms for Application Specific Instruction-set Processor, which includes both uniprocessor and multiprocessor.
For single-processor system, our focus is how to achieve an automated customization for specific instruction targeting to the multimedia applications, such as H.264. And for the multiprocessor, our focus is on the application partitioning and the communication mechanism setup. In this research, the experimental platform must consist of four steps: compile for C/C++ programs, profiling, specific instruction customization and processor simulation.

In conclusion, we need one configurable processor simulation tool to do the back-end work for the whole framework. It should be able to add the novel instructions into both the cross-compiler and simulator, and then do the simulation and corresponding analysis, which is used to evaluate the effect of the custom instructions. In addition, on this basis this tool should have the ability to simulate the multiprocessor system, and the XTMP toolset just satisfies this requirement. Therefore, the Xtensa-based toolset from Tensilica Inc. is our need.

"This year I have done many experiments using the Xtensa-based toolset, which has provided me with much needed help", said
ZhaoKang, Tsinghua University, Computer Science and Technology, EDA Lab

Previous Research

Because our research focuses on custom instruction generation, Tensilica's toolkit is appropriate.

Initially I want to utilize Xtensa Xplorer to be the back-end of our research's process, i.e. add custom instructions into the compiler, simulator, and then get the final simulation results. This strategy performs very well at present. Our current kernel task is to analyze the data flow graph (DFG) of the application program with our proposed algorithms, and then find out the suitable custom instructions. After receiving the custom instructions results, generate how to evaluate these new instructions, and how to simulate them in the reconfigurable processor? These back-end problems will be assisted by the Xtensa Xplorer software.

Lately, I have made a survey on the related researches with custom instructions, such as co-processor, multiprocessor, MPSoC, memory access optimization, etc. I found there exists a wide research space on the combination of custom instruction and other hot issues. For example, in the research on multiprocessor, considering custom instructions when partitioning on code, scheduling and binding will get a fire-new results.

Outline of Curriculum and Courses

• Design Automation for Digital Systems - Jinian Bian
• Introduction to VLSI Design - Yici Cai
• Layout Theory for VLSI Systems - Xianlong Hong, Qiang Zhou

Student/Assistants Outreach

• Kang Zhao, Ph.D. grade 4
• Shujun Deng, Ph.D. grade 4
• Yanni Zhao, Ph.D. grade 3
• Chenqian Jiang, Master, grade 1
• Xiaoqing Yang, Master, grade 3

Tsinghua University 's URL

Tsinghua University's Department of Computer Science & Technology's URL

Tsinghua University's EDA Laboratory project URL