Research on Link Optimization Technology Based on Basic Block Reordering

During program execution, the distribution of basic blocks directly impacts cache line filling, and an inefficient basic block layout can lead to reduced cache line hit rates, thereby affecting program performance. This study proposes a new optimization algorithm based on traditional basic block reordering, aiming to improve execution efficiency by particularly accounting for cache line considerations and inter-cluster call relationships in basic block layout. He algorithm begins by extracting program profile information and constructing a control flow graph (CFG) based on inter-block relationships, sizes, and other relevant data. Using cache line alignment and jump frequency, the basic blocks are then clustered. Following clustering, one or more hot chains are formed based on call relationships between clusters. Basic block layout adjustments are made within these hot chains, ultimately producing a new basic block order. Experimental results demonstrate that this algorithm effectively reduces i-cache miss rate by 1.45%, i-TLB miss rate by 0.17%, and branch miss rate by 3.35% in the gzip program, thus significantly improving execution efficiency.