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 "rndintl.s"
  30 
  31 #include "libm.h"
  32 LIBM_ANSI_PRAGMA_WEAK(aintl,function)
  33 LIBM_ANSI_PRAGMA_WEAK(irintl,function)
  34 LIBM_ANSI_PRAGMA_WEAK(anintl,function)
  35 LIBM_ANSI_PRAGMA_WEAK(nintl,function)
  36 #include "libm_synonyms.h"
  37 #undef fabs
  38 
  39         ENTRY(aintl)
  40         movl    %esp,%eax
  41         subl    $8,%esp
  42         fstcw   -8(%eax)
  43         fldt    4(%eax)
  44         movw    -8(%eax),%cx
  45         orw     $0x0c00,%cx
  46         movw    %cx,-4(%eax)
  47         fldcw   -4(%eax)                / set RD = to_zero
  48         frndint
  49         fstcw   -4(%eax)
  50         movw    -4(%eax),%dx
  51         andw    $0xf3ff,%dx
  52         movw    -8(%eax),%cx
  53         andw    $0x0c00,%cx
  54         orw     %dx,%cx
  55         movw    %cx,-8(%eax)
  56         fldcw   -8(%eax)                / restore RD
  57         addl    $8,%esp
  58         ret
  59         .align  4
  60         SET_SIZE(aintl)
  61 
  62         ENTRY(irintl)
  63         movl    %esp,%ecx
  64         subl    $8,%esp
  65         fldt    4(%ecx)                 / load x
  66         fistpl  -8(%ecx)                / [x]
  67         fwait
  68         movl    -8(%ecx),%eax
  69         addl    $8,%esp
  70         ret
  71         .align  4
  72         SET_SIZE(irintl)
  73 
  74         .data
  75         .align  4
  76 half:   .float  0.5
  77 
  78         ENTRY(anintl)
  79 .Lanintl:
  80         movl    %esp,%ecx
  81         subl    $8,%esp
  82         fstcw   -8(%ecx)
  83         fldt    4(%ecx)
  84         movw    -8(%ecx),%dx
  85         andw    $0xf3ff,%dx
  86         movw    %dx,-4(%ecx)
  87         fldcw   -4(%ecx)                / set RD = to_nearest
  88         fld     %st(0)
  89         frndint                         / [x],x
  90         fstcw   -4(%ecx)
  91         movw    -4(%ecx),%dx
  92         andw    $0xf3ff,%dx
  93         movw    -8(%ecx),%ax
  94         andw    $0x0c00,%ax
  95         orw     %dx,%ax
  96         movw    %ax,-8(%ecx)
  97         fldcw   -8(%ecx)                / restore RD
  98         fucom                           / check if x is already an integer
  99         fstsw   %ax
 100         sahf
 101         jp      .L0
 102         je      .L0
 103         fxch                            / x,[x]
 104         fsub    %st(1),%st              / x-[x],[x]
 105         fabs                            / |x-[x]|,[x]
 106         PIC_SETUP(1)
 107         fcoms   PIC_L(half)
 108         PIC_WRAPUP
 109         fnstsw  %ax
 110         sahf
 111         jae     .halfway                / if |x-[x]| = 0.5 goto halfway, 
 112                                         / most cases will not take branch.
 113 .L0:
 114         addl    $8,%esp
 115         fstp    %st(0)
 116         ret
 117 .halfway:
 118         / x = n+0.5, recompute anint(x) as x+sign(x)*0.5
 119         fldt    4(%ecx)                 / x, 0.5, [x]
 120         movw    12(%ecx),%ax            / sign+exp part of x
 121         andw    $0x8000,%ax             / look at sign bit
 122         jnz     .x_neg
 123         faddp
 124         addl    $8,%esp
 125         fstp    %st(1)
 126         ret
 127 .x_neg:
 128         / here, x is negative, so return x-0.5
 129         fsubp   %st,%st(1)              / x-0.5,[x]
 130         addl    $8,%esp
 131         fstp    %st(1)
 132         ret
 133         .align  4
 134         SET_SIZE(anintl)
 135 
 136         ENTRY(nintl)
 137         pushl   %ebp
 138         movl    %esp,%ebp
 139         subl    $8,%esp
 140         pushl   16(%ebp)
 141         pushl   12(%ebp)
 142         pushl   8(%ebp)
 143         call    .Lanintl                /// LOCAL
 144         fistpl  -8(%ebp)
 145         fwait
 146         movl    -8(%ebp),%eax
 147         leave
 148         ret
 149         .align  4
 150         SET_SIZE(nintl)