Re: [AD] malloc

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You wouldn't (nor shouldn't, directly). The compiler would. And since memory and video bitmap types are abstracted, if you access a bitmap you'll have no idea if the pointer the system gives you is aligned or not.

then a   bool IsAlignedPtr();     may be needed, before any SSE code.

SSE instructions can still be used inside a
if ( IsAlignedPtr() )
  SSE code
else
  i386 code

for each line.
SSE code can be used, even without using the  -mSSE
AFAIK -mSSE tells the compiler to generate its own SSE were appropriate, thats not going to prevent specific use of SSE.



nor will i386 instructions, so should we not bother with MMX either, as
i386 is good enough.

I never said don't bother with SSE. I just said MMX isn't going anywhere, and that it might not be a totally technical reason that Intel is pushing SSE and downplaying MMX.


I think there is some technical reasons; the guides from AMD and Intel say you cant mix SSE and MMX instructions, without having to use fence post, (a flushing instruction), which is basically anti-streaming. For these reasons i think Intel want to kill MMX, so there is sound technical reasons for it; however as you have pointed out, finacially for Intel... they will be carrying around those legacy MMX instructions for years to come.





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