arch/metag/lib/muldi3.S

   1 ! Copyright (C) 2012 by Imagination Technologies Ltd.
   2 !
   3 ! 64-bit multiply routine.
   4 !
   5
   6 !
   7 ! 64-bit signed/unsigned multiply
   8 !
   9 ! A = D1Ar1:D0Ar2 = a 2^48 + b 2^32 +  c 2^16 + d 2^0
  10 !
  11 ! B = D1Ar3:D0Ar4 = w 2^48 + x 2^32 +  y 2^16 + z 2^0
  12 !
  13         .text
  14         .global ___muldi3
  15         .type   ___muldi3,function
  16
  17 ___muldi3:
  18         MULD    D1Re0,D1Ar1,D0Ar4       ! (a 2^48 + b 2^32)(y 2^16 + z 2^0)
  19         MULD    D0Re0,D0Ar2,D1Ar3       ! (w 2^48 + x 2^32)(c 2^16 + d 2^0)
  20         ADD     D1Re0,D1Re0,D0Re0
  21
  22         MULW    D0Re0,D0Ar2,D0Ar4       ! (d 2^0)  * (z 2^0)
  23
  24         RTDW    D0Ar2,D0Ar2
  25         MULW    D0Ar6,D0Ar2,D0Ar4       ! (c 2^16)(z 2^0)
  26         LSR     D1Ar5,D0Ar6,#16
  27         LSL     D0Ar6,D0Ar6,#16
  28         ADDS    D0Re0,D0Re0,D0Ar6
  29         ADDCS   D1Re0,D1Re0,#1
  30         RTDW    D0Ar4,D0Ar4
  31         ADD     D1Re0,D1Re0,D1Ar5
  32
  33         MULW    D0Ar6,D0Ar2,D0Ar4       ! (c 2^16)(y 2^16)
  34         ADD     D1Re0,D1Re0,D0Ar6
  35
  36         RTDW    D0Ar2,D0Ar2
  37         MULW    D0Ar6,D0Ar2,D0Ar4       ! (d 2^0)(y 2^16)
  38         LSR     D1Ar5,D0Ar6,#16
  39         LSL     D0Ar6,D0Ar6,#16
  40         ADDS    D0Re0,D0Re0,D0Ar6
  41         ADD     D1Re0,D1Re0,D1Ar5
  42         ADDCS   D1Re0,D1Re0,#1
  43         MOV     PC, D1RtP
  44         .size ___muldi3,.-___muldi3