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  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  27  * Use is subject to license terms.
  28  */
  29 
  30 #pragma weak fdimf = __fdimf
  31 
  32 #include "libm.h"       /* for islessequal macro */
  33 
  34 float
  35 __fdimf(float x, float y) {
  36         /*
  37          * On SPARC v8plus/v9, this could be implemented as follows
  38          * (assuming %f0 = x, %f1 = y, return value left in %f0):
  39          *
  40          * fcmps        %fcc0,%f0,%f1
  41          * st           %g0,[scratch]   ! use fzero instead of st/ld
  42          * ld           [scratch],%f2   ! if VIS is available
  43          * fnegs        %f2,%f3
  44          * fmovsle      %fcc0,%f2,%f0
  45          * fmovsle      %fcc0,%f3,%f1
  46          * fsubs        %f0,%f1,%f0
  47          */
  48         if (islessequal(x, y)) {
  49                 x = 0.0f;
  50                 y = -x;
  51         }
  52         return (x - y);
  53 }