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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
|
|
