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Re: enabling SSE for 3-vector inner product


On Thu, 29 Apr 2010, Qianqian Fang wrote:

Here is my SSE3 vec_dot

struct CPU_float4{
   float x,y,z,w;
}
typedef struct CPU_float4 pvec;

Shouldn't there be some magic here for alignment purposes?


now I am trying to use SSE4.x DPPS, but gcc gave me
error. I don't know if I used it with a wrong format.

Did you try using the intrinsic _mm_dp_ps?


"dpps %%xmm0, %%xmm1, 0xF1 \n\t"

Maybe the order of the arguments is reversed in asm and it likes a $ before a constant (and it prefers fewer parentheses on the next line).


In any case, you shouldn't get a factor 2 compared to the SSE3 version, so that won't be enough for you.


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