xref: /aosp_15_r20/external/XNNPACK/src/f32-f16-vcvt/gen/vcvt-scalar-bitcast-x2.c (revision 4bdc94577ba0e567308109d787f7fec7b531ce36)

// Auto-generated file. Do not edit!
//   Template: src/f32-f16-vcvt/scalar-bitcast.c.in
//   Generator: tools/xngen
//
// Copyright 2021 Google LLC
//
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree.

#include <assert.h>

#include <xnnpack/common.h>
#include <xnnpack/math.h>
#include <xnnpack/vcvt.h>


void xnn_f32_f16_vcvt_ukernel__scalar_bitcast_x2(
    size_t n,
    const float* input,
    void* output,
    const union xnn_f32_f16_cvt_params params[restrict XNN_MIN_ELEMENTS(1)])
{
  assert(n != 0);
  assert(n % sizeof(float) == 0);
  assert(input != NULL);
  assert(output != NULL);

  const uint32_t vnonsign_mask = params->scalar_bitcast.nonsign_mask;
  const uint32_t vexp_bias = params->scalar_bitcast.exp_bias;
  const float vscale_to_inf = params->scalar_bitcast.scale_to_inf;
  const uint32_t vexpw_max = params->scalar_bitcast.expw_max;
  const float vscale_to_zero = params->scalar_bitcast.scale_to_zero;
  const uint32_t vbias_min = params->scalar_bitcast.bias_min;
  const uint16_t vexph_mask = params->scalar_bitcast.exph_mask;
  const uint16_t vmanth_mask = params->scalar_bitcast.manth_mask;
  const uint16_t vnanh = params->scalar_bitcast.nanh;

  const uint32_t* i = (const uint32_t*) input;
  uint16_t* o = (uint16_t*) output;
  for (; n >= 2 * sizeof(float); n -= 2 * sizeof(float)) {
    const uint32_t vw0 = i[0];
    const uint32_t vw1 = i[1];
    i += 2;

    const uint32_t vnonsignw0 = vw0 & vnonsign_mask;
    const uint32_t vnonsignw1 = vw1 & vnonsign_mask;

    float vf0 = uint32_as_float(vnonsignw0);
    float vf1 = uint32_as_float(vnonsignw1);
    const uint32_t vsignw0 = vw0 ^ vnonsignw0;
    const uint32_t vsignw1 = vw1 ^ vnonsignw1;
    uint32_t vbias0 = vnonsignw0 + vexp_bias;
    uint32_t vbias1 = vnonsignw1 + vexp_bias;

    vf0 *= vscale_to_inf;
    vf1 *= vscale_to_inf;
    vbias0 &= vexpw_max;
    vbias1 &= vexpw_max;

    vf0 *= vscale_to_zero;
    vf1 *= vscale_to_zero;
    vbias0 = math_max_u32(vbias0, vbias_min);
    vbias1 = math_max_u32(vbias1, vbias_min);

    vf0 += uint32_as_float(vbias0);
    vf1 += uint32_as_float(vbias1);

    const uint32_t vbits0 = float_as_uint32(vf0);
    const uint32_t vbits1 = float_as_uint32(vf1);

    const uint16_t vexph0 = (uint16_t) (vbits0 >> 13) & vexph_mask;
    const uint16_t vexph1 = (uint16_t) (vbits1 >> 13) & vexph_mask;
    const uint16_t vmanth0 = (uint16_t) vbits0 & vmanth_mask;
    const uint16_t vmanth1 = (uint16_t) vbits1 & vmanth_mask;
    const uint16_t vsignh0 = (uint16_t) (vsignw0 >> 16);
    const uint16_t vsignh1 = (uint16_t) (vsignw1 >> 16);

    uint16_t vh0 = vexph0 + vmanth0;
    uint16_t vh1 = vexph1 + vmanth1;
    if XNN_UNPREDICTABLE(vnonsignw0 > vexpw_max) {
      vh0 = vnanh;
    }
    if XNN_UNPREDICTABLE(vnonsignw1 > vexpw_max) {
      vh1 = vnanh;
    }
    vh0 |= vsignh0;
    vh1 |= vsignh1;

    o[0] = vh0;
    o[1] = vh1;
    o += 2;
  }
  if XNN_UNLIKELY(n != 0) {
    const uint32_t vw = *i;

    const uint32_t vnonsignw = vw & vnonsign_mask;

    float vf = uint32_as_float(vnonsignw);
    const uint32_t vsignw = vw ^ vnonsignw;
    uint32_t vbias = vnonsignw + vexp_bias;

    vf *= vscale_to_inf;
    vbias &= vexpw_max;

    vf *= vscale_to_zero;
    vbias = math_max_u32(vbias, vbias_min);

    vf += uint32_as_float(vbias);

    const uint32_t vbits = float_as_uint32(vf);

    const uint16_t vexph = (uint16_t) (vbits >> 13) & vexph_mask;
    const uint16_t vmanth = (uint16_t) vbits & vmanth_mask;
    const uint16_t vsignh = (uint16_t) (vsignw >> 16);

    uint16_t vh = vexph + vmanth;
    if XNN_UNPREDICTABLE(vnonsignw > vexpw_max) {
      vh = vnanh;
    }
    vh |= vsignh;

    *o = vh;
  }
}