usr/src/lib/libm/i386/src/remquol.s

   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 "remquol.s"
  30
  31 #include "libm.h"
  32 LIBM_ANSI_PRAGMA_WEAK(remquol,function)
  33 #include "libm_protos.h"
  34
  35         ENTRY(remquol)
  36         fldt    16(%esp)                / load arg y
  37         fldt    4(%esp)                 / load arg x
  38 .Lreml_loop:
  39         fprem1                          / partial remainder
  40         fstsw   %ax                     / store status word
  41         andw    $0x400,%ax              / check whether reduction complete
  42         jne     .Lreml_loop             / while reduction incomplete, do fprem1
  43         fstsw   %ax
  44         fwait
  45         fstp    %st(1)
  46         movw    %ax,%dx
  47         andw    $0x4000,%dx             / get C3
  48         sarw    $13,%dx
  49         movw    %ax,%cx
  50         andw    $0x100,%cx              / get C0
  51         sarw    $6,%cx
  52         addw    %cx,%dx
  53         andw    $0x200,%ax              / get C1
  54         sarw    $9,%ax
  55         addw    %dx,%ax
  56         cwtl
  57         movl    12(%esp),%edx           / sign and bexp of x
  58         movl    24(%esp),%ecx           / sign and bexp of y
  59         andl    $0x00008000,%edx        / edx <- sign(x)
  60         andl    $0x00008000,%ecx        / ecx <- sign(y)
  61         cmpl    %edx,%ecx
  62         je      .pos
  63         negl    %eax                    / negative n
  64 .pos:
  65         movl    28(%esp),%ecx
  66         movl    %eax,0(%ecx)            / last 3 significant bits of quotient
  67         ret
  68         .align  4
  69         SET_SIZE(remquol)