amd-builtins/math32/hypotF.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 "math32.h"
#if !defined(SUBNORMALS_SUPPORTED)
#include "floattointconversion.h"
#endif //SUBNORMALS_SUPPORTED

// Returns sqrt(x*x + y*y) with no overflow or underflow unless the result warrants it




__attribute__((overloadable, always_inline)) float
hypot(float x, float y)
{
    uint ux = as_uint(x);
    uint aux = ux & EXSIGNBIT_SP32;
    uint uy = as_uint(y);
    uint auy = uy & EXSIGNBIT_SP32;
	float retval;
    int c = aux > auy;
    ux = c ? aux : auy;
    uy = c ? auy : aux;

#if !defined(SUBNORMALS_SUPPORTED)
	if( as_float(uy) > 0.0 && ux < 0x7effffff)
	{
#endif	//SUBNORMALS_SUPPORTED
		int xexp = clamp((int)(ux >> EXPSHIFTBITS_SP32) - EXPBIAS_SP32, -126, 126);
		float fx_exp = as_float((xexp + EXPBIAS_SP32) << EXPSHIFTBITS_SP32);
		float fi_exp = as_float((-xexp + EXPBIAS_SP32) << EXPSHIFTBITS_SP32);
		float fx = as_float(ux) * fi_exp;
		float fy = as_float(uy) * fi_exp;
		retval = MATH_SQRT(mad(fx, fx, fy*fy)) * fx_exp;
#if !defined(SUBNORMALS_SUPPORTED)
	}
	else
	{
		double dy = float_uint_to_double(as_uint(y));
		double dx = float_uint_to_double(as_uint(x));
		double dretval = sqrt(dx*dx + dy*dy);
		retval = as_float(double_to_float_uint(dretval));
	}
#endif //SUBNORMALS_SUPPORTED

    retval = ux > PINFBITPATT_SP32 | uy == 0 ? as_float(ux) : retval;
    retval = ux == PINFBITPATT_SP32 | uy == PINFBITPATT_SP32 ? as_float(PINFBITPATT_SP32) : retval;
    return retval;
}