sysdeps/mips/mips64/submul_1.S

   1 /* MIPS3 __mpn_submul_1 -- Multiply a limb vector with a single limb and
   2  * subtract the product from a second limb vector.
   3  *
   4  * Copyright (C) 1992-2019 Free Software Foundation, Inc.
   5  *
   6  * This file is part of the GNU MP Library.
   7  *
   8  * The GNU MP Library is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU Lesser General Public License as published by
  10  * the Free Software Foundation; either version 2.1 of the License, or (at your
  11  * option) any later version.
  12  *
  13  * The GNU MP Library is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  16  * License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with the GNU MP Library.  If not, see
  20  * <http://www.gnu.org/licenses/>.
  21  */
  22
  23 #include <sysdep.h>
  24 #include <sys/asm.h>
  25
  26 /* INPUT PARAMETERS
  27  * res_ptr      $4
  28  * s1_ptr       $5
  29  * size         $6
  30  * s2_limb      $7
  31  */
  32
  33 #ifdef __PIC__
  34         .option pic2
  35 #endif
  36 ENTRY (__mpn_submul_1)
  37 #ifdef __PIC__
  38         SETUP_GP /* ??? unused */
  39 #endif
  40         .set    noreorder
  41         .set    nomacro
  42
  43  # warm up phase 0
  44         ld      $8,0($5)
  45
  46  # warm up phase 1
  47         daddiu  $5,$5,8
  48 #if __mips_isa_rev < 6
  49         dmultu  $8,$7
  50 #else
  51         dmulu   $11,$8,$7
  52         dmuhu   $12,$8,$7
  53 #endif
  54
  55         daddiu  $6,$6,-1
  56         beq     $6,$0,L(LC0)
  57         move    $2,$0           # zero cy2
  58
  59         daddiu  $6,$6,-1
  60         beq     $6,$0,L(LC1)
  61         ld      $8,0($5)        # load new s1 limb as early as possible
  62
  63 L(Loop):        ld      $10,0($4)
  64 #if __mips_isa_rev < 6
  65         mflo    $3
  66         mfhi    $9
  67 #else
  68         move    $3,$11
  69         move    $9,$12
  70 #endif
  71         daddiu  $5,$5,8
  72         daddu   $3,$3,$2        # add old carry limb to low product limb
  73 #if __mips_isa_rev < 6
  74         dmultu  $8,$7
  75 #else
  76         dmulu   $11,$8,$7
  77         dmuhu   $12,$8,$7
  78 #endif
  79         ld      $8,0($5)        # load new s1 limb as early as possible
  80         daddiu  $6,$6,-1        # decrement loop counter
  81         sltu    $2,$3,$2        # carry from previous addition -> $2
  82         dsubu   $3,$10,$3
  83         sgtu    $10,$3,$10
  84         daddu   $2,$2,$10
  85         sd      $3,0($4)
  86         daddiu  $4,$4,8
  87         bne     $6,$0,L(Loop)
  88         daddu   $2,$9,$2        # add high product limb and carry from addition
  89
  90  # cool down phase 1
  91 L(LC1): ld      $10,0($4)
  92 #if __mips_isa_rev < 6
  93         mflo    $3
  94         mfhi    $9
  95 #else
  96         move    $3,$11
  97         move    $9,$12
  98 #endif
  99         daddu   $3,$3,$2
 100         sltu    $2,$3,$2
 101 #if __mips_isa_rev < 6
 102         dmultu  $8,$7
 103 #else
 104         dmulu   $11,$8,$7
 105         dmuhu   $12,$8,$7
 106 #endif
 107         dsubu   $3,$10,$3
 108         sgtu    $10,$3,$10
 109         daddu   $2,$2,$10
 110         sd      $3,0($4)
 111         daddiu  $4,$4,8
 112         daddu   $2,$9,$2        # add high product limb and carry from addition
 113
 114  # cool down phase 0
 115 L(LC0): ld      $10,0($4)
 116 #if __mips_isa_rev < 6
 117         mflo    $3
 118         mfhi    $9
 119 #else
 120         move    $3,$11
 121         move    $9,$12
 122 #endif
 123         daddu   $3,$3,$2
 124         sltu    $2,$3,$2
 125         dsubu   $3,$10,$3
 126         sgtu    $10,$3,$10
 127         daddu   $2,$2,$10
 128         sd      $3,0($4)
 129         j       $31
 130         daddu   $2,$9,$2        # add high product limb and carry from addition
 131
 132 END (__mpn_submul_1)