On Sat, 26 Mar 2005 02:17:58 +0100, Steven Bosscher <[EMAIL PROTECTED]> wrote: > On Saturday 26 March 2005 02:22, Canqun Yang wrote: > > * loop.c (PREFETCH_BLOCKS_BEFORE_LOOP_MAX): Defined conditionally. > > (scan_loop): Change extra_size from 16 to 128. > > (emit_prefetch_instructions): Don't ignore all prefetches within > > loop. > > OK, so I know this is not a popular subject, but can we *please* stop > working on loop.c and focus on getting the new RTL and tree loop passes > to do what we want? All this loop.c patching is a typical example of > why free software development does not always work: always going for > the low-hanging fruit. In this case, there have been several attempts > to replace the prefetching stuff in loop.c with something better. On > the rtl-opt branch there is a new RTL loop-prefetch.c, and on the LNO > branch there is a re-use analysis based prefetching pass. Why don't > you try to finish and improve those passes, instead of making it yet > again harder to remove loop.c. This one file is a *huge* problem for > just about the entire RTL optimizer path. It is, for example, the > reason why there is no profile information available before this old > piece of, if I may say, junk runs, and it the only reason why a great > many functions in for example jump.c and the various cfg*.c files can > still not be removed.
Why can't we just kill this beast on HEAD _now_ and this way force people who experience regressions work on the new loop optimizer? We're waiting for that happening since 3.4 now... Richard.