Re: [arm-gnu] NEON usage

[42Bastian <list-bastian.schick@xxxxxxxxxxx>]

Am 11.05.2010 05:20, schrieb James:

> But the ARM NEON Intrinsics here:
> http://gcc.gnu.org/onlinedocs/gcc/ARM-NEON-Intrinsics.html
> 
> seems to suggest that 
> 
> int64x2_t vmlal_s32 (int64x2_t, int32x2_t, int32x2_t)
> 
> could be used?

Excuse my ignorance, but aren't intrinsics meant to be used by the
programmer ?

So you need to write:

int32x2_t x,y;
int64x2_t sum;
for(i = 0; i < N; i+=2){
  x = vld1_s32(&x[i]); y = vld1_s32(&y[i]);
  vmlal_s32(sum,x,y);
}
// add upper and lower 64bit
// shift down


-- 
42Bastian
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