// arm_simd.h - written and placed in public domain by Jeffrey Walton

/// \file arm_simd.h
/// \brief Support functions for ARM and vector operations

#ifndef CRYPTOPP_ARM_SIMD_H
#define CRYPTOPP_ARM_SIMD_H

#include "config.h"

// C1189: error: This header is specific to ARM targets
#if (CRYPTOPP_ARM_NEON_AVAILABLE) && !defined(_M_ARM64)
# include <arm_neon.h>
#endif

#if (CRYPTOPP_ARM_ACLE_AVAILABLE)
# include <stdint.h>
# include <arm_acle.h>
#endif

#if CRYPTOPP_ARM_PMULL_AVAILABLE

inline uint64x2_t PMULL_00(const uint64x2_t a, const uint64x2_t b)
{
#if defined(_MSC_VER)
    const __n64 x = { vgetq_lane_u64(a, 0) };
    const __n64 y = { vgetq_lane_u64(b, 0) };
    return vmull_p64(x, y);
#elif defined(__GNUC__)
    uint64x2_t r;
    __asm __volatile("pmull    %0.1q, %1.1d, %2.1d \n\t"
        :"=w" (r) : "w" (a), "w" (b) );
    return r;
#else
    return (uint64x2_t)(vmull_p64(
        vgetq_lane_u64(vreinterpretq_u64_u8(a),0),
        vgetq_lane_u64(vreinterpretq_u64_u8(b),0)));
#endif
}

inline uint64x2_t PMULL_01(const uint64x2_t a, const uint64x2_t b)
{
#if defined(_MSC_VER)
    const __n64 x = { vgetq_lane_u64(a, 0) };
    const __n64 y = { vgetq_lane_u64(b, 1) };
    return vmull_p64(x, y);
#elif defined(__GNUC__)
    uint64x2_t r;
    __asm __volatile("pmull    %0.1q, %1.1d, %2.1d \n\t"
        :"=w" (r) : "w" (a), "w" (vget_high_u64(b)) );
    return r;
#else
    return (uint64x2_t)(vmull_p64(
        vgetq_lane_u64(vreinterpretq_u64_u8(a),0),
        vgetq_lane_u64(vreinterpretq_u64_u8(b),1)));
#endif
}

inline uint64x2_t PMULL_10(const uint64x2_t a, const uint64x2_t b)
{
#if defined(_MSC_VER)
    const __n64 x = { vgetq_lane_u64(a, 1) };
    const __n64 y = { vgetq_lane_u64(b, 0) };
    return vmull_p64(x, y);
#elif defined(__GNUC__)
    uint64x2_t r;
    __asm __volatile("pmull    %0.1q, %1.1d, %2.1d \n\t"
        :"=w" (r) : "w" (vget_high_u64(a)), "w" (b) );
    return r;
#else
    return (uint64x2_t)(vmull_p64(
        vgetq_lane_u64(vreinterpretq_u64_u8(a),1),
        vgetq_lane_u64(vreinterpretq_u64_u8(b),0)));
#endif
}

inline uint64x2_t PMULL_11(const uint64x2_t a, const uint64x2_t b)
{
#if defined(_MSC_VER)
    const __n64 x = { vgetq_lane_u64(a, 1) };
    const __n64 y = { vgetq_lane_u64(b, 1) };
    return vmull_p64(x, y);
#elif defined(__GNUC__)
    uint64x2_t r;
    __asm __volatile("pmull2   %0.1q, %1.2d, %2.2d \n\t"
        :"=w" (r) : "w" (a), "w" (b) );
    return r;
#else
    return (uint64x2_t)(vmull_p64(
        vgetq_lane_u64(vreinterpretq_u64_u8(a),1),
        vgetq_lane_u64(vreinterpretq_u64_u8(b),1)));
#endif
}

inline uint64x2_t VEXT_U8(uint64x2_t a, uint64x2_t b, unsigned int c)
{
#if defined(_MSC_VER)
    return (uint64x2_t)vextq_u8(
        vreinterpretq_u8_u64(a), vreinterpretq_u8_u64(b), c);
#else
    uint64x2_t r;
    __asm __volatile("ext   %0.16b, %1.16b, %2.16b, %3 \n\t"
        :"=w" (r) : "w" (a), "w" (b), "I" (c) );
    return r;
#endif
}

// https://github.com/weidai11/cryptopp/issues/366
template <unsigned int C>
inline uint64x2_t VEXT_U8(uint64x2_t a, uint64x2_t b)
{
#if defined(_MSC_VER)
    return (uint64x2_t)vextq_u8(
        vreinterpretq_u8_u64(a), vreinterpretq_u8_u64(b), C);
#else
    uint64x2_t r;
    __asm __volatile("ext   %0.16b, %1.16b, %2.16b, %3 \n\t"
        :"=w" (r) : "w" (a), "w" (b), "I" (C) );
    return r;
#endif
}

#endif // CRYPTOPP_ARM_PMULL_AVAILABLE

#endif // CRYPTOPP_ARM_SIMD_H