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/* SPDX-License-Identifier: GPL-2.0 */
#include "libgcc.h"
;; This function also computes the remainder and stores it in er3.
.global __udivsi3
__udivsi3:
mov.w A1E,A1E ; denominator top word 0?
bne DenHighNonZero
; do it the easy way, see page 107 in manual
mov.w A0E,A2
extu.l A2P
divxu.w A1,A2P
mov.w A2E,A0E
divxu.w A1,A0P
mov.w A0E,A3
mov.w A2,A0E
extu.l A3P
rts
; er0 = er0 / er1
; er3 = er0 % er1
; trashes er1 er2
; expects er1 >= 2^16
DenHighNonZero:
mov.l er0,er3
mov.l er1,er2
#ifdef CONFIG_CPU_H8300H
divmod_L21:
shlr.l er0
shlr.l er2 ; make divisor < 2^16
mov.w e2,e2
bne divmod_L21
#else
shlr.l #2,er2 ; make divisor < 2^16
mov.w e2,e2
beq divmod_L22A
divmod_L21:
shlr.l #2,er0
divmod_L22:
shlr.l #2,er2 ; make divisor < 2^16
mov.w e2,e2
bne divmod_L21
divmod_L22A:
rotxl.w r2
bcs divmod_L23
shlr.l er0
bra divmod_L24
divmod_L23:
rotxr.w r2
shlr.l #2,er0
divmod_L24:
#endif
;; At this point,
;; er0 contains shifted dividend
;; er1 contains divisor
;; er2 contains shifted divisor
;; er3 contains dividend, later remainder
divxu.w r2,er0 ; r0 now contains the approximate quotient (AQ)
extu.l er0
beq divmod_L25
subs #1,er0 ; er0 = AQ - 1
mov.w e1,r2
mulxu.w r0,er2 ; er2 = upper (AQ - 1) * divisor
sub.w r2,e3 ; dividend - 65536 * er2
mov.w r1,r2
mulxu.w r0,er2 ; compute er3 = remainder (tentative)
sub.l er2,er3 ; er3 = dividend - (AQ - 1) * divisor
divmod_L25:
cmp.l er1,er3 ; is divisor < remainder?
blo divmod_L26
adds #1,er0
sub.l er1,er3 ; correct the remainder
divmod_L26:
rts
.end
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