tailieunhanh - High Level Synthesis: from Algorithm to Digital Circuit- P13

High Level Synthesis: from Algorithm to Digital Circuit- P13: This book presents an excellent collection of contributions addressing different aspects of high-level synthesis from both industry and academia. "High-Level Synthesis: from Algorithm to Digital Circuit" should be on each designer's and CAD developer's shelf, as well as on those of project managers who will soon embrace high level design and synthesis for all aspects of digital system design. | 6 AutoPilot A Platform-Based ESL Synthesis System 107 void block_idct short input 8 8 short output 8 8 short buffer 8 8 idct_row input buffer buffer output 2 Fig. Pseudo-code for an IDCT block Loop pipelining allows multiple successive iterations of a loop to operate in parallel by executing one iteration before the previous iteration has completed. As a result the loop throughput as well as the loop latency can be both improved. Hierarchical functional pipelining pipelines a function so that the same functional body can start processing new input data before its completion on the current data set. Given a target throughput constraint in terms of the number of cycles after which new data can be introduced the pipelining can be applied hierarchically to the callee functions. Multi-function pipelining executes two or more communicating functions concurrently in a streamed manner. For example Fig. illustrates an 8 x 8 inverse discrete cosine transform IDCT algorithm. Multi-function pipelining will pipeline the execution of row-based transform idct-row and column-based transform idct-col and automatically insert the ping-pong memory buffer to hold the intermediate data produced and consumed by these two functions. With this pipeline the overall throughput of the entire blockadct function can be significantly increased. Interface Synthesis With AutoPilot s platform-based synthesis methodology designers are not required to hard code any target-specific interface timing behaviors into the source code. Designers can simply use the standard function parameters to expose the desired inputs and outputs to the external circuits. AutoPilot interface synthesis is responsible for converting the parameter reads and writes into the actual interface accesses. For example based on the specified communication interfaces in the platform library a store operation on a scalar pointer . p x can be turned into a direct wire connection or a FIFO write or even a bus