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  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  23  */
  24 /*
  25  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  26  * Use is subject to license terms.
  27  */
  28 
  29         .file "isnanf.s"
  30 
  31 #include "libm.h"
  32 LIBM_ANSI_PRAGMA_WEAK(isnanf,function)
  33         .weak _isnanf
  34         .type _isnanf,@function
  35 _isnanf = __isnanf
  36 #include "libm_synonyms.h"
  37 
  38         ENTRY(isnanf)
  39         movl    4(%esp),%eax            / eax <-- x
  40         andl    $0x7fffffff,%eax        / eax <-- abs(x)
  41         subl    $0x7f800000,%eax        / ZF <-- 1      iff x is infinite
  42         jae     .nan_or_inf             / no jump iff arg. is finite
  43         movl    $0,%eax
  44         ret
  45 .nan_or_inf:
  46         jnz     .got_nan                / no jump if arg. infinite;
  47                                         / let nan waste time
  48         ret                             / %eax = 0 here
  49 .got_nan:
  50         movl    $1,%eax                 / %eax was 0, must be made 1 to
  51                                         / indicate TRUE 
  52         ret
  53         .align  4
  54         SET_SIZE(isnanf)
  55