The performance improvement on LBM previously achieved with improved software prefetching (36d4421) have gone lost recently withe00f189. There now is one memory access in the loop that LoopDataPrefetch cannot handle (while before there was none) which the heuristic rejects. This patch adds a small margin by allowing 1 non-prefetched memory access for every 32 prefetched ones, so that the heuristic doesn't bail in this type of case. Review: Ulrich Weigand Differential Revision: https://reviews.llvm.org/D92985
44 KiB
44 KiB