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[/] [openrisc/] [trunk/] [gnu-dev/] [or1k-gcc/] [libgcc/] [config/] [rl78/] [mulsi3.S] - Blame information for rev 848

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1 734 jeremybenn
;   Copyright (C) 2011 Free Software Foundation, Inc.
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;   Contributed by Red Hat.
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;
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; This file is free software; you can redistribute it and/or modify it
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; under the terms of the GNU General Public License as published by the
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; Free Software Foundation; either version 3, or (at your option) any
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; later version.
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;
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; This file is distributed in the hope that it will be useful, but
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; WITHOUT ANY WARRANTY; without even the implied warranty of
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; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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; General Public License for more details.
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;
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; Under Section 7 of GPL version 3, you are granted additional
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; permissions described in the GCC Runtime Library Exception, version
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; 3.1, as published by the Free Software Foundation.
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;
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; You should have received a copy of the GNU General Public License and
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; a copy of the GCC Runtime Library Exception along with this program;
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; see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
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; .
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;; 32x32=32 multiply
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; real
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; GAS defines r0..r7 as aliases for real registers; we want the saddr
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; forms here.
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r_0     =       0xffef8
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r_1     =       0xffef9
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r_2     =       0xffefa
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r_3     =       0xffefb
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r_4     =       0xffefc
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r_5     =       0xffefd
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r_6     =       0xffefe
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r_7     =       0xffeff
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; clobberable
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r8      =       0xffef0
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r9      =       0xffef1
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r10     =       0xffef2
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r11     =       0xffef3
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r12     =       0xffef4
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r13     =       0xffef5
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r14     =       0xffef6
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r15     =       0xffef7
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; preserved
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r16     =       0xffee8
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r17     =       0xffee9
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r18     =       0xffeea
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r19     =       0xffeeb
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r20     =       0xffeec
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r21     =       0xffeed
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r22     =       0xffeee
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r23     =       0xffeef
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;----------------------------------------------------------------------
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; Register use:
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;       RB0     RB1     RB2
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; AX    op2L    res32L  res32H
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; BC    op2H    (resH)  op1
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; DE    count   (resL-tmp)
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; HL    [sp+4]
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        .text
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        nop
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        .global ___mulsi3               ; (USI a, USI b)
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___mulsi3:
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        ;; A is at [sp+4]
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        ;; B is at [sp+8]
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        ;; result is in R8..R11
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        movw    ax, sp
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        addw    ax, #4
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        movw    hl, ax
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        sel     rb2
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        push    ax
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        push    bc
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        sel     rb0
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        clrw    ax
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        movw    r8, ax
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        movw    r16, ax
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        movw    ax, [hl+6]
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        cmpw    ax, #0
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        bz      $1f
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        cmpw    ax, #0xffff
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        bnz     $2f
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        movw    ax, [hl]
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        sel     rb1
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        subw    ax, r_0
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        sel     rb0
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        br      $1f
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2:
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        movw    bc, ax
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        movw    ax, [hl]
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        cmpw    ax, #0
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        skz
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        call    !.Lmul_hi
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1:
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        movw    ax, [hl+2]
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        cmpw    ax, #0
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        bz      $1f
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        cmpw    ax, #0xffff
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        bnz     $2f
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        movw    ax, [hl+4]
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        sel     rb1
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        subw    ax, r_0
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        sel     rb0
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        br      $1f
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2:
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        movw    bc, ax
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        movw    ax, [hl+4]
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        cmpw    ax, #0
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        skz
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        call    !.Lmul_hi
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1:
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        movw    ax, r8
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        movw    r16, ax
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        clrw    ax
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        movw    r8, ax
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        ;; now do R16:R8 += op1L * op2L
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        ;; op1 is in AX.0 (needs to shrw)
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        ;; op2 is in BC.2 and BC.1 (bc can shlw/rolcw)
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        ;; res is in AX.2 and AX.1 (needs to addw)
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        movw    ax, [hl]
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        movw    r10, ax         ; BC.1
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        movw    ax, [hl+4]
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        cmpw    ax, r10
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        bc      $.Lmul_hisi_top
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        movw    bc, r10
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        movw    r10, ax
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        movw    ax, bc
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.Lmul_hisi_top:
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        movw    bc, #0
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.Lmul_hisi_loop:
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        shrw    ax, 1
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        bnc     $.Lmul_hisi_no_add
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        sel     rb1
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        addw    ax, bc
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        sel     rb2
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        sknc
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        incw    ax
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        addw    ax, r_2
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.Lmul_hisi_no_add:
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        sel     rb1
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        shlw    bc, 1
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        sel     rb0
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        rolwc   bc, 1
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        cmpw    ax, #0
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        bz      $.Lmul_hisi_done
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        shrw    ax, 1
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        bnc     $.Lmul_hisi_no_add2
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        sel     rb1
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        addw    ax, bc
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        sel     rb2
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        sknc
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        incw    ax
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        addw    ax, r_2
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.Lmul_hisi_no_add2:
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        sel     rb1
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        shlw    bc, 1
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        sel     rb0
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        rolwc   bc, 1
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        cmpw    ax, #0
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        bnz     $.Lmul_hisi_loop
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.Lmul_hisi_done:
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        movw    ax, r16
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        movw    r10, ax
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        sel     rb2
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        pop     bc
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        pop     ax
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        sel     rb0
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        ret
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;----------------------------------------------------------------------
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        ;; R8 += AX * BC
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.Lmul_hi:
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        cmpw    ax, bc
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        skc
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        xchw    ax, bc
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        br      $.Lmul_hi_loop
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.Lmul_hi_top:
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        sel     rb1
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        addw    ax, r_2
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        sel     rb0
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.Lmul_hi_no_add:
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        shlw    bc, 1
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.Lmul_hi_loop:
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        shrw    ax, 1
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        bc      $.Lmul_hi_top
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        cmpw    ax, #0
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        bz      $.Lmul_hi_done
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        shlw    bc, 1
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        shrw    ax, 1
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        bc      $.Lmul_hi_top
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        cmpw    ax, #0
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        bnz     $.Lmul_hi_no_add
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.Lmul_hi_done:
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        ret
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;----------------------------------------------------------------------
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        .global ___mulhi3
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___mulhi3:
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        sel     rb1
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        clrw    ax
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        sel     rb0
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        movw    ax, sp
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        addw    ax, #4
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        movw    hl, ax
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        movw    ax, [hl+2]
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        movw    bc, ax
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        movw    ax, [hl]
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        br      $.Lmul_hi

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