On 10.09.2010 00:45, Marc Jones wrote: > Now that we have addressed the CAR/MMIO ROM copy issue (thanks Scott > and Arne), I wanted to revisit the other change that Arne proposed for > memset. > > http://article.gmane.org/gmane.linux.bios/57707 > > Some people didn't like the architecture specific code for memset. I > don't have a problem with it, but it did bring up a few questions. > > 1. Why isn't gcc generating the rep stosb itself? This should be a > standard optimization. > > 2. Why do we have functions for memset, memcpy, etc, when gcc has > builtins that could be used? Is this a remnant from romcc? >
Please note that the AMD and Intel manuals explicitly mention that some instructions which would be used by a fast memcpy will bypass the cache, and as such are unsuitable to copy CAR contents to RAM. Regards, Carl-Daniel -- http://www.hailfinger.org/ -- coreboot mailing list: [email protected] http://www.coreboot.org/mailman/listinfo/coreboot
