1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 
  22 /*
  23  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  24  */
  25 
  26 /*
  27  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  28  * Use is subject to license terms.
  29  */
  30 
  31 #pragma weak __hypotf = hypotf
  32 
  33 #include "libm.h"
  34 
  35 float
  36 hypotf(float x, float y)
  37 {
  38         double dx, dy;
  39         float w;
  40         int ix, iy;
  41 
  42         ix = (*(int *)&x) & 0x7fffffff;
  43         iy = (*(int *)&y) & 0x7fffffff;
  44 
  45         if (ix >= 0x7f800000) {
  46                 if (ix == 0x7f800000)
  47                         *(int *)&w = x == y ? iy : ix; /* w = |x| = inf */
  48                 else if (iy == 0x7f800000)
  49                         *(int *)&w = x == y ? ix : iy; /* w = |y| = inf */
  50                 else
  51                         w = fabsf(x) * fabsf(y); /* + -> * for Cheetah */
  52         } else if (iy >= 0x7f800000) {
  53                 if (iy == 0x7f800000)
  54                         *(int *)&w = x == y ? ix : iy;      /* w = |y| = inf */
  55                 else
  56                         w = fabsf(x) * fabsf(y); /* + -> * for Cheetah */
  57         } else if (ix == 0) {
  58                 *(int *)&w = iy; /* w = |y|  */
  59         } else if (iy == 0) {
  60                 *(int *)&w = ix; /* w = |x|  */
  61         } else {
  62                 dx = (double)x;
  63                 dy = (double)y;
  64                 w = (float)sqrt(dx * dx + dy * dy);
  65         }
  66 
  67         return (w);
  68 }