Function npyv_trunc_f32

numpy/core/src/common/simd/sse/math.h:371–390

    #define npyv_trunc_f64(A) _mm_round_pd(A, _MM_FROUND_TO_ZERO)
#else
    NPY_FINLINE npyv_f32 npyv_trunc_f32(npyv_f32 a)
    {
        const __m128 szero = _mm_set1_ps(-0.0f);
        const __m128i exp_mask = _mm_set1_epi32(0xff000000);

        __m128i nfinite_mask = _mm_slli_epi32(_mm_castps_si128(a), 1);
                nfinite_mask = _mm_and_si128(nfinite_mask, exp_mask);
                nfinite_mask = _mm_cmpeq_epi32(nfinite_mask, exp_mask);

        // eliminate nans/inf to avoid invalid fp errors
        __m128 x = _mm_xor_ps(a, _mm_castsi128_ps(nfinite_mask));
        __m128i trunci = _mm_cvttps_epi32(x);
        __m128 trunc = _mm_cvtepi32_ps(trunci);
        // respect signed zero, e.g. -0.5 -> -0.0
        trunc = _mm_or_ps(trunc, _mm_and_ps(a, szero));
        // if overflow return a
        __m128i overflow_mask = _mm_cmpeq_epi32(trunci, _mm_castps_si128(szero));
        // a if a overflow or nonfinite
        return npyv_select_f32(_mm_or_si128(nfinite_mask, overflow_mask), a, trunc);
    }
    NPY_FINLINE npyv_f64 npyv_trunc_f64(npyv_f64 a)
    {
        const __m128d one = _mm_set1_pd(1.0);