c++ - Constant floats with SIMD -


i've been trying hand @ optimising code have using microsoft's sse intrinsics. 1 of biggest problems when optimising code lhs happens whenever want use constant. there seems info on generating constants (here , here - section 13.4), assembly (which rather avoid).

the problem when try implement same thing intrinsics, msvc complains incompatible types etc. know of equivalent tricks using intrinsics?

example - generate {1.0,1.0,1.0,1.0}

//pcmpeqw xmm0,xmm0  __m128 t = _mm_cmpeq_epi16( t, t );  //pslld xmm0,25  _mm_slli_epi32(t, 25);  //psrld xmm0,2 return _mm_srli_epi32(t, 2);

this generates bunch of errors incompatible type (__m128 vs _m128i). i'm pretty new this, i'm pretty sure i'm missing obvious. can help?

tldr - how generate __m128 vec filled single precision constant floats ms intrinsics?

thanks reading :)

simply cast __m128i __m128 using _mm_castsi128_ps. also, second line should 

t = _mm_slli_epi32(t, 25)

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