On Identifying Segments of Traces for Dynamic Compilation

Typical computing systems based on general purpose processors (GPPs) are extended with coarse-grained reconfigurable arrays (CGRAs) to provide higher performance and/or energy savings. In order for applications to take advantage of these computing systems, efficient dynamic mapping techniques are required. Those dynamic mapping techniques will be responsible for automatically moving computations originally running in the GPP to the CGRA. The concept of dynamic compilation, widespread in the context of JIT compilation to GPPs, is receiving more attention by there configurable computing community. This paper presents our approach to dynamically map computations to CGRAs coupled to a GPP. Specifically, we present the identification of large sequences of instructions, MegaBlocks, being executed in a GPP. These MegaBlocks are then mapped to the target CGRA. We evaluate the potential of the MegaBlocks over Basic Blocks and Super Blocks to increase the IPC when targeting a CGRA and considering the execution of a number of representative benchmarks.