generic/lib/geometric/normalize.cl

/*
 * Copyright (c) 2014 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <clc/clc.h>

_CLC_OVERLOAD _CLC_DEF float normalize(float p) {
  return sign(p);
}

_CLC_OVERLOAD _CLC_DEF float2 normalize(float2 p) {
  if (all(p == (float2)0.0F))
    return p;

  float l2 = dot(p, p);

  if (l2 < FLT_MIN) {
    p *= 0x1.0p+86F;
    l2 = dot(p, p);
  } else if (l2 == INFINITY) {
    p *= 0x1.0p-65f;
    l2 = dot(p, p);
    if (l2 == INFINITY) {
      p = copysign(select((float2)0.0F, (float2)1.0F, isinf(p)), p);
      l2 = dot(p, p);
    }
  }
  return p * rsqrt(l2);
}

_CLC_OVERLOAD _CLC_DEF float3 normalize(float3 p) {
  if (all(p == (float3)0.0F))
    return p;

  float l2 = dot(p, p);

  if (l2 < FLT_MIN) {
    p *= 0x1.0p+86F;
    l2 = dot(p, p);
  } else if (l2 == INFINITY) {
    p *= 0x1.0p-66f;
    l2 = dot(p, p);
    if (l2 == INFINITY) {
      p = copysign(select((float3)0.0F, (float3)1.0F, isinf(p)), p);
      l2 = dot(p, p);
    }
  }
  return p * rsqrt(l2);
}

_CLC_OVERLOAD _CLC_DEF float4 normalize(float4 p) {
  if (all(p == (float4)0.0F))
    return p;

  float l2 = dot(p, p);

  if (l2 < FLT_MIN) {
    p *= 0x1.0p+86F;
    l2 = dot(p, p);
  } else if (l2 == INFINITY) {
    p *= 0x1.0p-66f;
    l2 = dot(p, p);
    if (l2 == INFINITY) {
      p = copysign(select((float4)0.0F, (float4)1.0F, isinf(p)), p);
      l2 = dot(p, p);
    }
  }
  return p * rsqrt(l2);
}

#ifdef cl_khr_fp64

#pragma OPENCL EXTENSION cl_khr_fp64 : enable

_CLC_OVERLOAD _CLC_DEF double normalize(double p) {
  return sign(p);
}

_CLC_OVERLOAD _CLC_DEF double2 normalize(double2 p) {
  if (all(p == (double2)0.0))
    return p;

  double l2 = dot(p, p);

  if (l2 < DBL_MIN) {
    p *= 0x1.0p+563;
    l2 = dot(p, p);
  } else if (l2 == INFINITY) {
    p *= 0x1.0p-513;
    l2 = dot(p, p);
    if (l2 == INFINITY) {
      p = copysign(select((double2)0.0, (double2)1.0, isinf(p)), p);
      l2 = dot(p, p);
    }
  }
  return p * rsqrt(l2);
}

_CLC_OVERLOAD _CLC_DEF double3 normalize(double3 p) {
  if (all(p == (double3)0.0))
    return p;

  double l2 = dot(p, p);

  if (l2 < DBL_MIN) {
    p *= 0x1.0p+563;
    l2 = dot(p, p);
  } else if (l2 == INFINITY) {
    p *= 0x1.0p-514;
    l2 = dot(p, p);
    if (l2 == INFINITY) {
      p = copysign(select((double3)0.0, (double3)1.0, isinf(p)), p);
      l2 = dot(p, p);
    }
  }
  return p * rsqrt(l2);
}

_CLC_OVERLOAD _CLC_DEF double4 normalize(double4 p) {
  if (all(p == (double4)0.0))
    return p;

  double l2 = dot(p, p);

  if (l2 < DBL_MIN) {
    p *= 0x1.0p+563;
    l2 = dot(p, p);
  } else if (l2 == INFINITY) {
    p *= 0x1.0p-514;
    l2 = dot(p, p);
    if (l2 == INFINITY) {
      p = copysign(select((double4)0.0, (double4)1.0, isinf(p)), p);
      l2 = dot(p, p);
    }
  }
  return p * rsqrt(l2);
}

#endif