//
// Copyright 2011-2012 Ettus Research LLC
// Copyright 2018 Ettus Research, a National Instruments Company
//
// SPDX-License-Identifier: GPL-3.0-or-later
//

#include "convert_common.hpp"
#include <uhd/utils/byteswap.hpp>
#include <emmintrin.h>

using namespace uhd::convert;

DECLARE_CONVERTER(sc16_item32_le, 1, fc32, 1, PRIORITY_SIMD)
{
    const item32_t* input = reinterpret_cast<const item32_t*>(inputs[0]);
    fc32_t* output        = reinterpret_cast<fc32_t*>(outputs[0]);

    const __m128 scalar = _mm_set_ps1(float(scale_factor) / (1 << 16));
    const __m128i zeroi = _mm_setzero_si128();

// this macro converts values faster by using SSE intrinsics to convert 4 values at a time
#define convert_item32_1_to_fc32_1_nswap_guts(_al_)                                    \
    for (; i + 3 < nsamps; i += 4) {                                                   \
        /* load from input */                                                          \
        __m128i tmpi = _mm_loadu_si128(reinterpret_cast<const __m128i*>(input + i));   \
                                                                                       \
        /* unpack + swap 16-bit pairs */                                               \
        tmpi           = _mm_shufflelo_epi16(tmpi, _MM_SHUFFLE(2, 3, 0, 1));           \
        tmpi           = _mm_shufflehi_epi16(tmpi, _MM_SHUFFLE(2, 3, 0, 1));           \
        __m128i tmpilo = _mm_unpacklo_epi16(zeroi, tmpi); /* value in upper 16 bits */ \
        __m128i tmpihi = _mm_unpackhi_epi16(zeroi, tmpi);                              \
                                                                                       \
        /* convert and scale */                                                        \
        __m128 tmplo = _mm_mul_ps(_mm_cvtepi32_ps(tmpilo), scalar);                    \
        __m128 tmphi = _mm_mul_ps(_mm_cvtepi32_ps(tmpihi), scalar);                    \
                                                                                       \
        /* store to output */                                                          \
        _mm_store##_al_##ps(reinterpret_cast<float*>(output + i + 0), tmplo);          \
        _mm_store##_al_##ps(reinterpret_cast<float*>(output + i + 2), tmphi);          \
    }

    size_t i = 0;

    // need to dispatch according to alignment for fastest conversion
    switch (size_t(output) & 0xf) {
        case 0x0:
            // the data is 16-byte aligned, so do the fast processing of the bulk of the
            // samples
            convert_item32_1_to_fc32_1_nswap_guts(_) break;
        case 0x8:
            // the first sample is 8-byte aligned - process it to align the remainder of
            // the samples to 16-bytes
            item32_sc16_to_xx<uhd::htowx>(input, output, 1, scale_factor);
            i++;
            // do faster processing of the bulk of the samples now that we are 16-byte
            // aligned
            convert_item32_1_to_fc32_1_nswap_guts(_) break;
        default:
            // we are not 8 or 16-byte aligned, so do fast processing with the unaligned
            // load and store
            convert_item32_1_to_fc32_1_nswap_guts(u_)
    }

    // convert any remaining samples
    item32_sc16_to_xx<uhd::htowx>(input + i, output + i, nsamps - i, scale_factor);
}

DECLARE_CONVERTER(sc16_item32_be, 1, fc32, 1, PRIORITY_SIMD)
{
    const item32_t* input = reinterpret_cast<const item32_t*>(inputs[0]);
    fc32_t* output        = reinterpret_cast<fc32_t*>(outputs[0]);

    const __m128 scalar = _mm_set_ps1(float(scale_factor) / (1 << 16));
    const __m128i zeroi = _mm_setzero_si128();

// this macro converts values faster by using SSE intrinsics to convert 4 values at a time
#define convert_item32_1_to_fc32_1_bswap_guts(_al_)                                      \
    for (; i + 3 < nsamps; i += 4) {                                                     \
        /* load from input */                                                            \
        __m128i tmpi = _mm_loadu_si128(reinterpret_cast<const __m128i*>(input + i));     \
                                                                                         \
        /* byteswap + unpack -> byteswap 16 bit words */                                 \
        tmpi           = _mm_or_si128(_mm_srli_epi16(tmpi, 8), _mm_slli_epi16(tmpi, 8)); \
        __m128i tmpilo = _mm_unpacklo_epi16(zeroi, tmpi); /* value in upper 16 bits */   \
        __m128i tmpihi = _mm_unpackhi_epi16(zeroi, tmpi);                                \
                                                                                         \
        /* convert and scale */                                                          \
        __m128 tmplo = _mm_mul_ps(_mm_cvtepi32_ps(tmpilo), scalar);                      \
        __m128 tmphi = _mm_mul_ps(_mm_cvtepi32_ps(tmpihi), scalar);                      \
                                                                                         \
        /* store to output */                                                            \
        _mm_store##_al_##ps(reinterpret_cast<float*>(output + i + 0), tmplo);            \
        _mm_store##_al_##ps(reinterpret_cast<float*>(output + i + 2), tmphi);            \
    }

    size_t i = 0;

    // need to dispatch according to alignment for fastest conversion
    switch (size_t(output) & 0xf) {
        case 0x0:
            // the data is 16-byte aligned, so do the fast processing of the bulk of the
            // samples
            convert_item32_1_to_fc32_1_bswap_guts(_) break;
        case 0x8:
            // the first sample is 8-byte aligned - process it to align the remainder of
            // the samples to 16-bytes
            item32_sc16_to_xx<uhd::htonx>(input, output, 1, scale_factor);
            i++;
            // do faster processing of the bulk of the samples now that we are 16-byte
            // aligned
            convert_item32_1_to_fc32_1_bswap_guts(_) break;
        default:
            // we are not 8 or 16-byte aligned, so do fast processing with the unaligned
            // load and store
            convert_item32_1_to_fc32_1_bswap_guts(u_)
    }

    // convert any remaining samples
    item32_sc16_to_xx<uhd::htonx>(input + i, output + i, nsamps - i, scale_factor);
}

DECLARE_CONVERTER(sc16_chdr, 1, fc32, 1, PRIORITY_SIMD)
{
    const sc16_t* input = reinterpret_cast<const sc16_t*>(inputs[0]);
    fc32_t* output      = reinterpret_cast<fc32_t*>(outputs[0]);

    const __m128 scalar = _mm_set_ps1(float(scale_factor) / (1 << 16));
    const __m128i zeroi = _mm_setzero_si128();

// this macro converts values faster by using SSE intrinsics to convert 4 values at a time
#define convert_item32_1_to_fc32_1_guts(_al_)                                          \
    for (; i + 3 < nsamps; i += 4) {                                                   \
        /* load from input */                                                          \
        __m128i tmpi = _mm_loadu_si128(reinterpret_cast<const __m128i*>(input + i));   \
                                                                                       \
        /* unpack + swap 16-bit pairs */                                               \
        __m128i tmpilo = _mm_unpacklo_epi16(zeroi, tmpi); /* value in upper 16 bits */ \
        __m128i tmpihi = _mm_unpackhi_epi16(zeroi, tmpi);                              \
                                                                                       \
        /* convert and scale */                                                        \
        __m128 tmplo = _mm_mul_ps(_mm_cvtepi32_ps(tmpilo), scalar);                    \
        __m128 tmphi = _mm_mul_ps(_mm_cvtepi32_ps(tmpihi), scalar);                    \
                                                                                       \
        /* store to output */                                                          \
        _mm_store##_al_##ps(reinterpret_cast<float*>(output + i + 0), tmplo);          \
        _mm_store##_al_##ps(reinterpret_cast<float*>(output + i + 2), tmphi);          \
    }

    size_t i = 0;

    // need to dispatch according to alignment for fastest conversion
    switch (size_t(output) & 0xf) {
        case 0x0:
            // the data is 16-byte aligned, so do the fast processing of the bulk of the
            // samples
            convert_item32_1_to_fc32_1_guts(_) break;
        case 0x8:
            // the first sample is 8-byte aligned - process it to align the remainder of
            // the samples to 16-bytes
            chdr_sc16_to_xx(input, output, 1, scale_factor);
            i++;
            // do faster processing of the bulk of the samples now that we are 16-byte
            // aligned
            convert_item32_1_to_fc32_1_guts(_) break;
        default:
            // we are not 8 or 16-byte aligned, so do fast processing with the unaligned
            // load and store
            convert_item32_1_to_fc32_1_guts(u_)
    }

    // convert any remaining samples
    chdr_sc16_to_xx(input + i, output + i, nsamps - i, scale_factor);
}