[SDL] SDL_memcpy variants used in SDL_BlitCopy

Alex Volkov avcp-sdlmail at usa.net
Mon Sep 12 23:09:33 PDT 2005


Hello, all.
I am wondering is SDL_memcpyMMX() and SDL_memcpySSE() are actually faster
than plain memcpy() on any Intel chips. My tests of copying 1Meg buffer of
regular memory run on Windows 2000, 1.7MHz Intel Xeon show that the MMX
version is 2-4% slower and the SSE version is ~45% *slower* than a regular
intrinsic/inline memcpy() using "rep movsd".

Did anyone run similar tests on other chips and/or platform? What were the
results? I am really curious.

If these versions are faster on an AMD chip then they should only be enabled
for an AMD chip, right?

Regards,
Alex.






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