volk_32f_expfast_32f.h

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/* -*- c++ -*- */
/*
 * Copyright 2014 Free Software Foundation, Inc.
 *
 * This file is part of VOLK
 *
 * SPDX-License-Identifier: LGPL-3.0-or-later
 */
 
#include <inttypes.h>
#include <math.h>
#include <stdio.h>
 
#define Mln2 0.6931471805f
#define A 8388608.0f
#define B 1065353216.0f
#define C 60801.0f
 
 
#ifndef INCLUDED_volk_32f_expfast_32f_a_H
#define INCLUDED_volk_32f_expfast_32f_a_H
 
#if LV_HAVE_AVX && LV_HAVE_FMA
 
#include <immintrin.h>
 
static inline void volk_32f_expfast_32f_a_avx_fma(float* bVector,
                                                  const float* aVector,
                                                  unsigned int num_points)
{
    float* bPtr = bVector;
    const float* aPtr = aVector;
 
    unsigned int number = 0;
    const unsigned int eighthPoints = num_points / 8;
 
    __m256 aVal, bVal, a, b;
    __m256i exp;
    a = _mm256_set1_ps(A / Mln2);
    b = _mm256_set1_ps(B - C);
 
    for (; number < eighthPoints; number++) {
        aVal = _mm256_load_ps(aPtr);
        exp = _mm256_cvtps_epi32(_mm256_fmadd_ps(a, aVal, b));
        bVal = _mm256_castsi256_ps(exp);
 
        _mm256_store_ps(bPtr, bVal);
        aPtr += 8;
        bPtr += 8;
    }
 
    number = eighthPoints * 8;
    for (; number < num_points; number++) {
        *bPtr++ = expf(*aPtr++);
    }
}
 
#endif /* LV_HAVE_AVX && LV_HAVE_FMA for aligned */
 
#ifdef LV_HAVE_AVX
 
#include <immintrin.h>
 
static inline void
volk_32f_expfast_32f_a_avx(float* bVector, const float* aVector, unsigned int num_points)
{
    float* bPtr = bVector;
    const float* aPtr = aVector;
 
    unsigned int number = 0;
    const unsigned int eighthPoints = num_points / 8;
 
    __m256 aVal, bVal, a, b;
    __m256i exp;
    a = _mm256_set1_ps(A / Mln2);
    b = _mm256_set1_ps(B - C);
 
    for (; number < eighthPoints; number++) {
        aVal = _mm256_load_ps(aPtr);
        exp = _mm256_cvtps_epi32(_mm256_add_ps(_mm256_mul_ps(a, aVal), b));
        bVal = _mm256_castsi256_ps(exp);
 
        _mm256_store_ps(bPtr, bVal);
        aPtr += 8;
        bPtr += 8;
    }
 
    number = eighthPoints * 8;
    for (; number < num_points; number++) {
        *bPtr++ = expf(*aPtr++);
    }
}
 
#endif /* LV_HAVE_AVX for aligned */
 
#ifdef LV_HAVE_SSE4_1
#include <smmintrin.h>
 
static inline void volk_32f_expfast_32f_a_sse4_1(float* bVector,
                                                 const float* aVector,
                                                 unsigned int num_points)
{
    float* bPtr = bVector;
    const float* aPtr = aVector;
 
    unsigned int number = 0;
    const unsigned int quarterPoints = num_points / 4;
 
    __m128 aVal, bVal, a, b;
    __m128i exp;
    a = _mm_set1_ps(A / Mln2);
    b = _mm_set1_ps(B - C);
 
    for (; number < quarterPoints; number++) {
        aVal = _mm_load_ps(aPtr);
        exp = _mm_cvtps_epi32(_mm_add_ps(_mm_mul_ps(a, aVal), b));
        bVal = _mm_castsi128_ps(exp);
 
        _mm_store_ps(bPtr, bVal);
        aPtr += 4;
        bPtr += 4;
    }
 
    number = quarterPoints * 4;
    for (; number < num_points; number++) {
        *bPtr++ = expf(*aPtr++);
    }
}
 
#endif /* LV_HAVE_SSE4_1 for aligned */
 
#endif /* INCLUDED_volk_32f_expfast_32f_a_H */
 
#ifndef INCLUDED_volk_32f_expfast_32f_u_H
#define INCLUDED_volk_32f_expfast_32f_u_H
 
#if LV_HAVE_AVX && LV_HAVE_FMA
#include <immintrin.h>
 
static inline void volk_32f_expfast_32f_u_avx_fma(float* bVector,
                                                  const float* aVector,
                                                  unsigned int num_points)
{
    float* bPtr = bVector;
    const float* aPtr = aVector;
 
    unsigned int number = 0;
    const unsigned int eighthPoints = num_points / 8;
 
    __m256 aVal, bVal, a, b;
    __m256i exp;
    a = _mm256_set1_ps(A / Mln2);
    b = _mm256_set1_ps(B - C);
 
    for (; number < eighthPoints; number++) {
        aVal = _mm256_loadu_ps(aPtr);
        exp = _mm256_cvtps_epi32(_mm256_fmadd_ps(a, aVal, b));
        bVal = _mm256_castsi256_ps(exp);
 
        _mm256_storeu_ps(bPtr, bVal);
        aPtr += 8;
        bPtr += 8;
    }
 
    number = eighthPoints * 8;
    for (; number < num_points; number++) {
        *bPtr++ = expf(*aPtr++);
    }
}
 
#endif /* LV_HAVE_AVX && LV_HAVE_FMA for unaligned */
 
#ifdef LV_HAVE_AVX
#include <immintrin.h>
 
static inline void
volk_32f_expfast_32f_u_avx(float* bVector, const float* aVector, unsigned int num_points)
{
    float* bPtr = bVector;
    const float* aPtr = aVector;
 
    unsigned int number = 0;
    const unsigned int eighthPoints = num_points / 8;
 
    __m256 aVal, bVal, a, b;
    __m256i exp;
    a = _mm256_set1_ps(A / Mln2);
    b = _mm256_set1_ps(B - C);
 
    for (; number < eighthPoints; number++) {
        aVal = _mm256_loadu_ps(aPtr);
        exp = _mm256_cvtps_epi32(_mm256_add_ps(_mm256_mul_ps(a, aVal), b));
        bVal = _mm256_castsi256_ps(exp);
 
        _mm256_storeu_ps(bPtr, bVal);
        aPtr += 8;
        bPtr += 8;
    }
 
    number = eighthPoints * 8;
    for (; number < num_points; number++) {
        *bPtr++ = expf(*aPtr++);
    }
}
 
#endif /* LV_HAVE_AVX for unaligned */
 
 
#ifdef LV_HAVE_SSE4_1
#include <smmintrin.h>
 
static inline void volk_32f_expfast_32f_u_sse4_1(float* bVector,
                                                 const float* aVector,
                                                 unsigned int num_points)
{
    float* bPtr = bVector;
    const float* aPtr = aVector;
 
    unsigned int number = 0;
    const unsigned int quarterPoints = num_points / 4;
 
    __m128 aVal, bVal, a, b;
    __m128i exp;
    a = _mm_set1_ps(A / Mln2);
    b = _mm_set1_ps(B - C);
 
    for (; number < quarterPoints; number++) {
        aVal = _mm_loadu_ps(aPtr);
        exp = _mm_cvtps_epi32(_mm_add_ps(_mm_mul_ps(a, aVal), b));
        bVal = _mm_castsi128_ps(exp);
 
        _mm_storeu_ps(bPtr, bVal);
        aPtr += 4;
        bPtr += 4;
    }
 
    number = quarterPoints * 4;
    for (; number < num_points; number++) {
        *bPtr++ = expf(*aPtr++);
    }
}
 
#endif /* LV_HAVE_SSE4_1 for unaligned */
 
 
#ifdef LV_HAVE_GENERIC
 
static inline void volk_32f_expfast_32f_generic(float* bVector,
                                                const float* aVector,
                                                unsigned int num_points)
{
    float* bPtr = bVector;
    const float* aPtr = aVector;
    unsigned int number = 0;
 
    for (number = 0; number < num_points; number++) {
        *bPtr++ = expf(*aPtr++);
    }
}
#endif /* LV_HAVE_GENERIC */
 
#ifdef LV_HAVE_NEON
#include <arm_neon.h>
 
static inline void
volk_32f_expfast_32f_neon(float* bVector, const float* aVector, unsigned int num_points)
{
    float* bPtr = bVector;
    const float* aPtr = aVector;
 
    unsigned int number = 0;
    const unsigned int quarterPoints = num_points / 4;
 
    float32x4_t a = vdupq_n_f32(A / Mln2);
    float32x4_t b = vdupq_n_f32(B - C);
 
    for (; number < quarterPoints; number++) {
        float32x4_t aVal = vld1q_f32(aPtr);
        int32x4_t exp = vcvtq_s32_f32(vmlaq_f32(b, a, aVal));
        float32x4_t bVal = vreinterpretq_f32_s32(exp);
        vst1q_f32(bPtr, bVal);
 
        aPtr += 4;
        bPtr += 4;
    }
 
    number = quarterPoints * 4;
    for (; number < num_points; number++) {
        *bPtr++ = expf(*aPtr++);
    }
}
 
#endif /* LV_HAVE_NEON */
 
#ifdef LV_HAVE_NEONV8
#include <arm_neon.h>
 
static inline void
volk_32f_expfast_32f_neonv8(float* bVector, const float* aVector, unsigned int num_points)
{
    float* bPtr = bVector;
    const float* aPtr = aVector;
 
    unsigned int number = 0;
    const unsigned int eighthPoints = num_points / 8;
 
    float32x4_t a = vdupq_n_f32(A / Mln2);
    float32x4_t b = vdupq_n_f32(B - C);
 
    for (; number < eighthPoints; number++) {
        __VOLK_PREFETCH(aPtr + 16);
 
        float32x4_t aVal0 = vld1q_f32(aPtr);
        float32x4_t aVal1 = vld1q_f32(aPtr + 4);
 
        int32x4_t exp0 = vcvtq_s32_f32(vfmaq_f32(b, a, aVal0));
        int32x4_t exp1 = vcvtq_s32_f32(vfmaq_f32(b, a, aVal1));
 
        float32x4_t bVal0 = vreinterpretq_f32_s32(exp0);
        float32x4_t bVal1 = vreinterpretq_f32_s32(exp1);
 
        vst1q_f32(bPtr, bVal0);
        vst1q_f32(bPtr + 4, bVal1);
 
        aPtr += 8;
        bPtr += 8;
    }
 
    number = eighthPoints * 8;
    for (; number < num_points; number++) {
        *bPtr++ = expf(*aPtr++);
    }
}
 
#endif /* LV_HAVE_NEONV8 */
 
#ifdef LV_HAVE_RVV
#include <riscv_vector.h>
 
static inline void
volk_32f_expfast_32f_rvv(float* bVector, const float* aVector, unsigned int num_points)
{
    size_t vlmax = __riscv_vsetvlmax_e32m8();
    const vfloat32m8_t ca = __riscv_vfmv_v_f_f32m8(A / Mln2, vlmax);
    const vfloat32m8_t cb = __riscv_vfmv_v_f_f32m8(B - C, vlmax);
 
    size_t n = num_points;
    for (size_t vl; n > 0; n -= vl, aVector += vl, bVector += vl) {
        vl = __riscv_vsetvl_e32m8(n);
        vfloat32m8_t v = __riscv_vle32_v_f32m8(aVector, vl);
        v = __riscv_vfmadd(v, ca, cb, vl);
        v = __riscv_vreinterpret_f32m8(__riscv_vfcvt_x(v, vl));
        __riscv_vse32(bVector, v, vl);
    }
}
#endif /*LV_HAVE_RVV*/
 
#endif /* INCLUDED_volk_32f_expfast_32f_u_H */