Reducing Code Management Overhead in Software-Managed Multicores Jian Cai, Yooseong Kim, Youngbin Kim, Aviral Shrivastava, Kyoungwoo Lee Compiler Microarchitecture Lab Arizona State University

Motivation Software managed multicore (SMM) architectures Have scratchpad memories (SPMs) instead of caches as on-chip memory Consumes significant less area and power but require explicit data movement Management overhead and must be minimized Code management divides SPM space into memory regions, and map functions into the regions Previous works focus on finding better mapping to reduce data transfers caused by conflicts among functions in the same region, but blindly insert management functions around every function call This paper reduces computation by avoiding unnecessary management calls by an always-hit analysis to identify functions that are always present in SPM a first-miss analysis to identify functions that are always present in SPM within loops _get(main) is not necessary since main is the only function in region 0 _get(F1) is hoisted since F1 is the only function in region 1 called within the loop We have developped and are developping management techniques for other data segments, but this paper focuses on code management. The always-hit and first-miss analyses are both iterative data-flow analysis

Result 14% improvement on average 9% improvement on average