root/arch/x86/math-emu/mul_Xsig.S

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*---------------------------------------------------------------------------+
   3  |  mul_Xsig.S                                                               |
   4  |                                                                           |
   5  | Multiply a 12 byte fixed point number by another fixed point number.      |
   6  |                                                                           |
   7  | Copyright (C) 1992,1994,1995                                              |
   8  |                       W. Metzenthen, 22 Parker St, Ormond, Vic 3163,      |
   9  |                       Australia.  E-mail billm@jacobi.maths.monash.edu.au |
  10  |                                                                           |
  11  | Call from C as:                                                           |
  12  |   void mul32_Xsig(Xsig *x, unsigned b)                                    |
  13  |                                                                           |
  14  |   void mul64_Xsig(Xsig *x, unsigned long long *b)                         |
  15  |                                                                           |
  16  |   void mul_Xsig_Xsig(Xsig *x, unsigned *b)                                |
  17  |                                                                           |
  18  | The result is neither rounded nor normalized, and the ls bit or so may    |
  19  | be wrong.                                                                 |
  20  |                                                                           |
  21  +---------------------------------------------------------------------------*/
  22         .file   "mul_Xsig.S"
  23 
  24 
  25 #include "fpu_emu.h"
  26 
  27 .text
  28 ENTRY(mul32_Xsig)
  29         pushl %ebp
  30         movl %esp,%ebp
  31         subl $16,%esp
  32         pushl %esi
  33 
  34         movl PARAM1,%esi
  35         movl PARAM2,%ecx
  36 
  37         xor %eax,%eax
  38         movl %eax,-4(%ebp)
  39         movl %eax,-8(%ebp)
  40 
  41         movl (%esi),%eax        /* lsl of Xsig */
  42         mull %ecx               /* msl of b */
  43         movl %edx,-12(%ebp)
  44 
  45         movl 4(%esi),%eax       /* midl of Xsig */
  46         mull %ecx               /* msl of b */
  47         addl %eax,-12(%ebp)
  48         adcl %edx,-8(%ebp)
  49         adcl $0,-4(%ebp)
  50 
  51         movl 8(%esi),%eax       /* msl of Xsig */
  52         mull %ecx               /* msl of b */
  53         addl %eax,-8(%ebp)
  54         adcl %edx,-4(%ebp)
  55 
  56         movl -12(%ebp),%eax
  57         movl %eax,(%esi)
  58         movl -8(%ebp),%eax
  59         movl %eax,4(%esi)
  60         movl -4(%ebp),%eax
  61         movl %eax,8(%esi)
  62 
  63         popl %esi
  64         leave
  65         ret
  66 ENDPROC(mul32_Xsig)
  67 
  68 
  69 ENTRY(mul64_Xsig)
  70         pushl %ebp
  71         movl %esp,%ebp
  72         subl $16,%esp
  73         pushl %esi
  74 
  75         movl PARAM1,%esi
  76         movl PARAM2,%ecx
  77 
  78         xor %eax,%eax
  79         movl %eax,-4(%ebp)
  80         movl %eax,-8(%ebp)
  81 
  82         movl (%esi),%eax        /* lsl of Xsig */
  83         mull 4(%ecx)            /* msl of b */
  84         movl %edx,-12(%ebp)
  85 
  86         movl 4(%esi),%eax       /* midl of Xsig */
  87         mull (%ecx)             /* lsl of b */
  88         addl %edx,-12(%ebp)
  89         adcl $0,-8(%ebp)
  90         adcl $0,-4(%ebp)
  91 
  92         movl 4(%esi),%eax       /* midl of Xsig */
  93         mull 4(%ecx)            /* msl of b */
  94         addl %eax,-12(%ebp)
  95         adcl %edx,-8(%ebp)
  96         adcl $0,-4(%ebp)
  97 
  98         movl 8(%esi),%eax       /* msl of Xsig */
  99         mull (%ecx)             /* lsl of b */
 100         addl %eax,-12(%ebp)
 101         adcl %edx,-8(%ebp)
 102         adcl $0,-4(%ebp)
 103 
 104         movl 8(%esi),%eax       /* msl of Xsig */
 105         mull 4(%ecx)            /* msl of b */
 106         addl %eax,-8(%ebp)
 107         adcl %edx,-4(%ebp)
 108 
 109         movl -12(%ebp),%eax
 110         movl %eax,(%esi)
 111         movl -8(%ebp),%eax
 112         movl %eax,4(%esi)
 113         movl -4(%ebp),%eax
 114         movl %eax,8(%esi)
 115 
 116         popl %esi
 117         leave
 118         ret
 119 ENDPROC(mul64_Xsig)
 120 
 121 
 122 
 123 ENTRY(mul_Xsig_Xsig)
 124         pushl %ebp
 125         movl %esp,%ebp
 126         subl $16,%esp
 127         pushl %esi
 128 
 129         movl PARAM1,%esi
 130         movl PARAM2,%ecx
 131 
 132         xor %eax,%eax
 133         movl %eax,-4(%ebp)
 134         movl %eax,-8(%ebp)
 135 
 136         movl (%esi),%eax        /* lsl of Xsig */
 137         mull 8(%ecx)            /* msl of b */
 138         movl %edx,-12(%ebp)
 139 
 140         movl 4(%esi),%eax       /* midl of Xsig */
 141         mull 4(%ecx)            /* midl of b */
 142         addl %edx,-12(%ebp)
 143         adcl $0,-8(%ebp)
 144         adcl $0,-4(%ebp)
 145 
 146         movl 8(%esi),%eax       /* msl of Xsig */
 147         mull (%ecx)             /* lsl of b */
 148         addl %edx,-12(%ebp)
 149         adcl $0,-8(%ebp)
 150         adcl $0,-4(%ebp)
 151 
 152         movl 4(%esi),%eax       /* midl of Xsig */
 153         mull 8(%ecx)            /* msl of b */
 154         addl %eax,-12(%ebp)
 155         adcl %edx,-8(%ebp)
 156         adcl $0,-4(%ebp)
 157 
 158         movl 8(%esi),%eax       /* msl of Xsig */
 159         mull 4(%ecx)            /* midl of b */
 160         addl %eax,-12(%ebp)
 161         adcl %edx,-8(%ebp)
 162         adcl $0,-4(%ebp)
 163 
 164         movl 8(%esi),%eax       /* msl of Xsig */
 165         mull 8(%ecx)            /* msl of b */
 166         addl %eax,-8(%ebp)
 167         adcl %edx,-4(%ebp)
 168 
 169         movl -12(%ebp),%edx
 170         movl %edx,(%esi)
 171         movl -8(%ebp),%edx
 172         movl %edx,4(%esi)
 173         movl -4(%ebp),%edx
 174         movl %edx,8(%esi)
 175 
 176         popl %esi
 177         leave
 178         ret
 179 ENDPROC(mul_Xsig_Xsig)