Messages in this thread | | | From | "H. Peter Anvin" <> | Subject | Re: [BK+PATCH] remove __constant_memcpy | Date | 17 Apr 2003 17:29:23 -0700 |
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Followup to: <Pine.LNX.4.44.0304171654530.14595-100000@home.transmeta.com> By author: Linus Torvalds <torvalds@transmeta.com> In newsgroup: linux.dev.kernel > > > 2) why no sse2-optimized memcpy? just that noone has done one yet? > > Yes. If you want to, it's definitely the right thing to do. More so than > the 3dnow stuff that is by now ancient. HOWEVER, I don't think there are > any really valid large memcpy() calls inside the kernel. All the valid > ones are either special-cased (ie "copy_page()") or to user space. >
It's questionable, though, if SSE-2 buys you anything SSE-1 doesn't already have. SSE-2 is basically integer and scalar ops for SSE, but data moving and even XOR is perfectly well handled by SSE-1.
-hpa -- <hpa@transmeta.com> at work, <hpa@zytor.com> in private! "Unix gives you enough rope to shoot yourself in the foot." Architectures needed: ia64 m68k mips64 ppc ppc64 s390 s390x sh v850 x86-64 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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