gcc/libgcc/config/avr/lib1funcs-fixed.S

875 lines
21 KiB
ArmAsm

/* -*- Mode: Asm -*- */
;; Copyright (C) 2012
;; Free Software Foundation, Inc.
;; Contributed by Sean D'Epagnier (sean@depagnier.com)
;; Georg-Johann Lay (avr@gjlay.de)
;; This file is free software; you can redistribute it and/or modify it
;; under the terms of the GNU General Public License as published by the
;; Free Software Foundation; either version 3, or (at your option) any
;; later version.
;; In addition to the permissions in the GNU General Public License, the
;; Free Software Foundation gives you unlimited permission to link the
;; compiled version of this file into combinations with other programs,
;; and to distribute those combinations without any restriction coming
;; from the use of this file. (The General Public License restrictions
;; do apply in other respects; for example, they cover modification of
;; the file, and distribution when not linked into a combine
;; executable.)
;; This file is distributed in the hope that it will be useful, but
;; WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
;; General Public License for more details.
;; You should have received a copy of the GNU General Public License
;; along with this program; see the file COPYING. If not, write to
;; the Free Software Foundation, 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Fixed point library routines for AVR
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.section .text.libgcc.fixed, "ax", @progbits
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Conversions to float
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
#if defined (L_fractqqsf)
DEFUN __fractqqsf
;; Move in place for SA -> SF conversion
clr r22
mov r23, r24
lsl r23
;; Sign-extend
sbc r24, r24
mov r25, r24
XJMP __fractsasf
ENDF __fractqqsf
#endif /* L_fractqqsf */
#if defined (L_fractuqqsf)
DEFUN __fractuqqsf
;; Move in place for USA -> SF conversion
clr r22
mov r23, r24
;; Zero-extend
clr r24
clr r25
XJMP __fractusasf
ENDF __fractuqqsf
#endif /* L_fractuqqsf */
#if defined (L_fracthqsf)
DEFUN __fracthqsf
;; Move in place for SA -> SF conversion
wmov 22, 24
lsl r22
rol r23
;; Sign-extend
sbc r24, r24
mov r25, r24
XJMP __fractsasf
ENDF __fracthqsf
#endif /* L_fracthqsf */
#if defined (L_fractuhqsf)
DEFUN __fractuhqsf
;; Move in place for USA -> SF conversion
wmov 22, 24
;; Zero-extend
clr r24
clr r25
XJMP __fractusasf
ENDF __fractuhqsf
#endif /* L_fractuhqsf */
#if defined (L_fracthasf)
DEFUN __fracthasf
;; Move in place for SA -> SF conversion
clr r22
mov r23, r24
mov r24, r25
;; Sign-extend
lsl r25
sbc r25, r25
XJMP __fractsasf
ENDF __fracthasf
#endif /* L_fracthasf */
#if defined (L_fractuhasf)
DEFUN __fractuhasf
;; Move in place for USA -> SF conversion
clr r22
mov r23, r24
mov r24, r25
;; Zero-extend
clr r25
XJMP __fractusasf
ENDF __fractuhasf
#endif /* L_fractuhasf */
#if defined (L_fractsqsf)
DEFUN __fractsqsf
XCALL __floatsisf
;; Divide non-zero results by 2^31 to move the
;; decimal point into place
tst r25
breq 0f
subi r24, exp_lo (31)
sbci r25, exp_hi (31)
0: ret
ENDF __fractsqsf
#endif /* L_fractsqsf */
#if defined (L_fractusqsf)
DEFUN __fractusqsf
XCALL __floatunsisf
;; Divide non-zero results by 2^32 to move the
;; decimal point into place
cpse r25, __zero_reg__
subi r25, exp_hi (32)
ret
ENDF __fractusqsf
#endif /* L_fractusqsf */
#if defined (L_fractsasf)
DEFUN __fractsasf
XCALL __floatsisf
;; Divide non-zero results by 2^16 to move the
;; decimal point into place
cpse r25, __zero_reg__
subi r25, exp_hi (16)
ret
ENDF __fractsasf
#endif /* L_fractsasf */
#if defined (L_fractusasf)
DEFUN __fractusasf
XCALL __floatunsisf
;; Divide non-zero results by 2^16 to move the
;; decimal point into place
cpse r25, __zero_reg__
subi r25, exp_hi (16)
ret
ENDF __fractusasf
#endif /* L_fractusasf */
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; Conversions from float
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
#if defined (L_fractsfqq)
DEFUN __fractsfqq
;; Multiply with 2^{24+7} to get a QQ result in r25
subi r24, exp_lo (-31)
sbci r25, exp_hi (-31)
XCALL __fixsfsi
mov r24, r25
ret
ENDF __fractsfqq
#endif /* L_fractsfqq */
#if defined (L_fractsfuqq)
DEFUN __fractsfuqq
;; Multiply with 2^{24+8} to get a UQQ result in r25
subi r25, exp_hi (-32)
XCALL __fixunssfsi
mov r24, r25
ret
ENDF __fractsfuqq
#endif /* L_fractsfuqq */
#if defined (L_fractsfha)
DEFUN __fractsfha
;; Multiply with 2^24 to get a HA result in r25:r24
subi r25, exp_hi (-24)
XJMP __fixsfsi
ENDF __fractsfha
#endif /* L_fractsfha */
#if defined (L_fractsfuha)
DEFUN __fractsfuha
;; Multiply with 2^24 to get a UHA result in r25:r24
subi r25, exp_hi (-24)
XJMP __fixunssfsi
ENDF __fractsfuha
#endif /* L_fractsfuha */
#if defined (L_fractsfhq)
DEFUN __fractsfsq
ENDF __fractsfsq
DEFUN __fractsfhq
;; Multiply with 2^{16+15} to get a HQ result in r25:r24
;; resp. with 2^31 to get a SQ result in r25:r22
subi r24, exp_lo (-31)
sbci r25, exp_hi (-31)
XJMP __fixsfsi
ENDF __fractsfhq
#endif /* L_fractsfhq */
#if defined (L_fractsfuhq)
DEFUN __fractsfusq
ENDF __fractsfusq
DEFUN __fractsfuhq
;; Multiply with 2^{16+16} to get a UHQ result in r25:r24
;; resp. with 2^32 to get a USQ result in r25:r22
subi r25, exp_hi (-32)
XJMP __fixunssfsi
ENDF __fractsfuhq
#endif /* L_fractsfuhq */
#if defined (L_fractsfsa)
DEFUN __fractsfsa
;; Multiply with 2^16 to get a SA result in r25:r22
subi r25, exp_hi (-16)
XJMP __fixsfsi
ENDF __fractsfsa
#endif /* L_fractsfsa */
#if defined (L_fractsfusa)
DEFUN __fractsfusa
;; Multiply with 2^16 to get a USA result in r25:r22
subi r25, exp_hi (-16)
XJMP __fixunssfsi
ENDF __fractsfusa
#endif /* L_fractsfusa */
;; For multiplication the functions here are called directly from
;; avr-fixed.md instead of using the standard libcall mechanisms.
;; This can make better code because GCC knows exactly which
;; of the call-used registers (not all of them) are clobbered. */
/*******************************************************
Fractional Multiplication 8 x 8 without MUL
*******************************************************/
#if defined (L_mulqq3) && !defined (__AVR_HAVE_MUL__)
;;; R23 = R24 * R25
;;; Clobbers: __tmp_reg__, R22, R24, R25
;;; Rounding: ???
DEFUN __mulqq3
XCALL __fmuls
;; TR 18037 requires that (-1) * (-1) does not overflow
;; The only input that can produce -1 is (-1)^2.
dec r23
brvs 0f
inc r23
0: ret
ENDF __mulqq3
#endif /* L_mulqq3 && ! HAVE_MUL */
/*******************************************************
Fractional Multiply .16 x .16 with and without MUL
*******************************************************/
#if defined (L_mulhq3)
;;; Same code with and without MUL, but the interfaces differ:
;;; no MUL: (R25:R24) = (R22:R23) * (R24:R25)
;;; Clobbers: ABI, called by optabs
;;; MUL: (R25:R24) = (R19:R18) * (R27:R26)
;;; Clobbers: __tmp_reg__, R22, R23
;;; Rounding: -0.5 LSB <= error <= 0.5 LSB
DEFUN __mulhq3
XCALL __mulhisi3
;; Shift result into place
lsl r23
rol r24
rol r25
brvs 1f
;; Round
sbrc r23, 7
adiw r24, 1
ret
1: ;; Overflow. TR 18037 requires (-1)^2 not to overflow
ldi r24, lo8 (0x7fff)
ldi r25, hi8 (0x7fff)
ret
ENDF __mulhq3
#endif /* defined (L_mulhq3) */
#if defined (L_muluhq3)
;;; Same code with and without MUL, but the interfaces differ:
;;; no MUL: (R25:R24) *= (R23:R22)
;;; Clobbers: ABI, called by optabs
;;; MUL: (R25:R24) = (R19:R18) * (R27:R26)
;;; Clobbers: __tmp_reg__, R22, R23
;;; Rounding: -0.5 LSB < error <= 0.5 LSB
DEFUN __muluhq3
XCALL __umulhisi3
;; Round
sbrc r23, 7
adiw r24, 1
ret
ENDF __muluhq3
#endif /* L_muluhq3 */
/*******************************************************
Fixed Multiply 8.8 x 8.8 with and without MUL
*******************************************************/
#if defined (L_mulha3)
;;; Same code with and without MUL, but the interfaces differ:
;;; no MUL: (R25:R24) = (R22:R23) * (R24:R25)
;;; Clobbers: ABI, called by optabs
;;; MUL: (R25:R24) = (R19:R18) * (R27:R26)
;;; Clobbers: __tmp_reg__, R22, R23
;;; Rounding: -0.5 LSB <= error <= 0.5 LSB
DEFUN __mulha3
XCALL __mulhisi3
XJMP __muluha3_round
ENDF __mulha3
#endif /* L_mulha3 */
#if defined (L_muluha3)
;;; Same code with and without MUL, but the interfaces differ:
;;; no MUL: (R25:R24) *= (R23:R22)
;;; Clobbers: ABI, called by optabs
;;; MUL: (R25:R24) = (R19:R18) * (R27:R26)
;;; Clobbers: __tmp_reg__, R22, R23
;;; Rounding: -0.5 LSB < error <= 0.5 LSB
DEFUN __muluha3
XCALL __umulhisi3
XJMP __muluha3_round
ENDF __muluha3
#endif /* L_muluha3 */
#if defined (L_muluha3_round)
DEFUN __muluha3_round
;; Shift result into place
mov r25, r24
mov r24, r23
;; Round
sbrc r22, 7
adiw r24, 1
ret
ENDF __muluha3_round
#endif /* L_muluha3_round */
/*******************************************************
Fixed Multiplication 16.16 x 16.16
*******************************************************/
#if defined (__AVR_HAVE_MUL__)
;; Multiplier
#define A0 16
#define A1 A0+1
#define A2 A1+1
#define A3 A2+1
;; Multiplicand
#define B0 20
#define B1 B0+1
#define B2 B1+1
#define B3 B2+1
;; Result
#define C0 24
#define C1 C0+1
#define C2 C1+1
#define C3 C2+1
#if defined (L_mulusa3)
;;; (C3:C0) = (A3:A0) * (B3:B0)
;;; Clobbers: __tmp_reg__
;;; Rounding: -0.5 LSB < error <= 0.5 LSB
DEFUN __mulusa3
;; Some of the MUL instructions have LSBs outside the result.
;; Don't ignore these LSBs in order to tame rounding error.
;; Use C2/C3 for these LSBs.
clr C0
clr C1
mul A0, B0 $ movw C2, r0
mul A1, B0 $ add C3, r0 $ adc C0, r1
mul A0, B1 $ add C3, r0 $ adc C0, r1 $ rol C1
;; Round
sbrc C3, 7
adiw C0, 1
;; The following MULs don't have LSBs outside the result.
;; C2/C3 is the high part.
mul A0, B2 $ add C0, r0 $ adc C1, r1 $ sbc C2, C2
mul A1, B1 $ add C0, r0 $ adc C1, r1 $ sbci C2, 0
mul A2, B0 $ add C0, r0 $ adc C1, r1 $ sbci C2, 0
neg C2
mul A0, B3 $ add C1, r0 $ adc C2, r1 $ sbc C3, C3
mul A1, B2 $ add C1, r0 $ adc C2, r1 $ sbci C3, 0
mul A2, B1 $ add C1, r0 $ adc C2, r1 $ sbci C3, 0
mul A3, B0 $ add C1, r0 $ adc C2, r1 $ sbci C3, 0
neg C3
mul A1, B3 $ add C2, r0 $ adc C3, r1
mul A2, B2 $ add C2, r0 $ adc C3, r1
mul A3, B1 $ add C2, r0 $ adc C3, r1
mul A2, B3 $ add C3, r0
mul A3, B2 $ add C3, r0
clr __zero_reg__
ret
ENDF __mulusa3
#endif /* L_mulusa3 */
#if defined (L_mulsa3)
;;; (C3:C0) = (A3:A0) * (B3:B0)
;;; Clobbers: __tmp_reg__
;;; Rounding: -0.5 LSB <= error <= 0.5 LSB
DEFUN __mulsa3
XCALL __mulusa3
tst B3
brpl 1f
sub C2, A0
sbc C3, A1
1: sbrs A3, 7
ret
sub C2, B0
sbc C3, B1
ret
ENDF __mulsa3
#endif /* L_mulsa3 */
#undef A0
#undef A1
#undef A2
#undef A3
#undef B0
#undef B1
#undef B2
#undef B3
#undef C0
#undef C1
#undef C2
#undef C3
#else /* __AVR_HAVE_MUL__ */
#define A0 18
#define A1 A0+1
#define A2 A0+2
#define A3 A0+3
#define B0 22
#define B1 B0+1
#define B2 B0+2
#define B3 B0+3
#define C0 22
#define C1 C0+1
#define C2 C0+2
#define C3 C0+3
;; __tmp_reg__
#define CC0 0
;; __zero_reg__
#define CC1 1
#define CC2 16
#define CC3 17
#define AA0 26
#define AA1 AA0+1
#define AA2 30
#define AA3 AA2+1
#if defined (L_mulsa3)
;;; (R25:R22) *= (R21:R18)
;;; Clobbers: ABI, called by optabs
;;; Rounding: -1 LSB <= error <= 1 LSB
DEFUN __mulsa3
push B0
push B1
bst B3, 7
XCALL __mulusa3
;; A survived in 31:30:27:26
rcall 1f
pop AA1
pop AA0
bst AA3, 7
1: brtc 9f
;; 1-extend A/B
sub C2, AA0
sbc C3, AA1
9: ret
ENDF __mulsa3
#endif /* L_mulsa3 */
#if defined (L_mulusa3)
;;; (R25:R22) *= (R21:R18)
;;; Clobbers: ABI, called by optabs and __mulsua
;;; Rounding: -1 LSB <= error <= 1 LSB
;;; Does not clobber T and A[] survives in 26, 27, 30, 31
DEFUN __mulusa3
push CC2
push CC3
; clear result
clr __tmp_reg__
wmov CC2, CC0
; save multiplicand
wmov AA0, A0
wmov AA2, A2
rjmp 3f
;; Loop the integral part
1: ;; CC += A * 2^n; n >= 0
add CC0,A0 $ adc CC1,A1 $ adc CC2,A2 $ adc CC3,A3
2: ;; A <<= 1
lsl A0 $ rol A1 $ rol A2 $ rol A3
3: ;; IBIT(B) >>= 1
;; Carry = n-th bit of B; n >= 0
lsr B3
ror B2
brcs 1b
sbci B3, 0
brne 2b
;; Loop the fractional part
;; B2/B3 is 0 now, use as guard bits for rounding
;; Restore multiplicand
wmov A0, AA0
wmov A2, AA2
rjmp 5f
4: ;; CC += A:Guard * 2^n; n < 0
add B3,B2 $ adc CC0,A0 $ adc CC1,A1 $ adc CC2,A2 $ adc CC3,A3
5:
;; A:Guard >>= 1
lsr A3 $ ror A2 $ ror A1 $ ror A0 $ ror B2
;; FBIT(B) <<= 1
;; Carry = n-th bit of B; n < 0
lsl B0
rol B1
brcs 4b
sbci B0, 0
brne 5b
;; Move result into place and round
lsl B3
wmov C2, CC2
wmov C0, CC0
clr __zero_reg__
adc C0, __zero_reg__
adc C1, __zero_reg__
adc C2, __zero_reg__
adc C3, __zero_reg__
;; Epilogue
pop CC3
pop CC2
ret
ENDF __mulusa3
#endif /* L_mulusa3 */
#undef A0
#undef A1
#undef A2
#undef A3
#undef B0
#undef B1
#undef B2
#undef B3
#undef C0
#undef C1
#undef C2
#undef C3
#undef AA0
#undef AA1
#undef AA2
#undef AA3
#undef CC0
#undef CC1
#undef CC2
#undef CC3
#endif /* __AVR_HAVE_MUL__ */
/*******************************************************
Fractional Division 8 / 8
*******************************************************/
#define r_divd r25 /* dividend */
#define r_quo r24 /* quotient */
#define r_div r22 /* divisor */
#if defined (L_divqq3)
DEFUN __divqq3
mov r0, r_divd
eor r0, r_div
sbrc r_div, 7
neg r_div
sbrc r_divd, 7
neg r_divd
cp r_divd, r_div
breq __divqq3_minus1 ; if equal return -1
XCALL __udivuqq3
lsr r_quo
sbrc r0, 7 ; negate result if needed
neg r_quo
ret
__divqq3_minus1:
ldi r_quo, 0x80
ret
ENDF __divqq3
#endif /* defined (L_divqq3) */
#if defined (L_udivuqq3)
DEFUN __udivuqq3
clr r_quo ; clear quotient
inc __zero_reg__ ; init loop counter, used per shift
__udivuqq3_loop:
lsl r_divd ; shift dividend
brcs 0f ; dividend overflow
cp r_divd,r_div ; compare dividend & divisor
brcc 0f ; dividend >= divisor
rol r_quo ; shift quotient (with CARRY)
rjmp __udivuqq3_cont
0:
sub r_divd,r_div ; restore dividend
lsl r_quo ; shift quotient (without CARRY)
__udivuqq3_cont:
lsl __zero_reg__ ; shift loop-counter bit
brne __udivuqq3_loop
com r_quo ; complement result
; because C flag was complemented in loop
ret
ENDF __udivuqq3
#endif /* defined (L_udivuqq3) */
#undef r_divd
#undef r_quo
#undef r_div
/*******************************************************
Fractional Division 16 / 16
*******************************************************/
#define r_divdL 26 /* dividend Low */
#define r_divdH 27 /* dividend Hig */
#define r_quoL 24 /* quotient Low */
#define r_quoH 25 /* quotient High */
#define r_divL 22 /* divisor */
#define r_divH 23 /* divisor */
#define r_cnt 21
#if defined (L_divhq3)
DEFUN __divhq3
mov r0, r_divdH
eor r0, r_divH
sbrs r_divH, 7
rjmp 1f
NEG2 r_divL
1:
sbrs r_divdH, 7
rjmp 2f
NEG2 r_divdL
2:
cp r_divdL, r_divL
cpc r_divdH, r_divH
breq __divhq3_minus1 ; if equal return -1
XCALL __udivuhq3
lsr r_quoH
ror r_quoL
brpl 9f
;; negate result if needed
NEG2 r_quoL
9:
ret
__divhq3_minus1:
ldi r_quoH, 0x80
clr r_quoL
ret
ENDF __divhq3
#endif /* defined (L_divhq3) */
#if defined (L_udivuhq3)
DEFUN __udivuhq3
sub r_quoH,r_quoH ; clear quotient and carry
;; FALLTHRU
ENDF __udivuhq3
DEFUN __udivuha3_common
clr r_quoL ; clear quotient
ldi r_cnt,16 ; init loop counter
__udivuhq3_loop:
rol r_divdL ; shift dividend (with CARRY)
rol r_divdH
brcs __udivuhq3_ep ; dividend overflow
cp r_divdL,r_divL ; compare dividend & divisor
cpc r_divdH,r_divH
brcc __udivuhq3_ep ; dividend >= divisor
rol r_quoL ; shift quotient (with CARRY)
rjmp __udivuhq3_cont
__udivuhq3_ep:
sub r_divdL,r_divL ; restore dividend
sbc r_divdH,r_divH
lsl r_quoL ; shift quotient (without CARRY)
__udivuhq3_cont:
rol r_quoH ; shift quotient
dec r_cnt ; decrement loop counter
brne __udivuhq3_loop
com r_quoL ; complement result
com r_quoH ; because C flag was complemented in loop
ret
ENDF __udivuha3_common
#endif /* defined (L_udivuhq3) */
/*******************************************************
Fixed Division 8.8 / 8.8
*******************************************************/
#if defined (L_divha3)
DEFUN __divha3
mov r0, r_divdH
eor r0, r_divH
sbrs r_divH, 7
rjmp 1f
NEG2 r_divL
1:
sbrs r_divdH, 7
rjmp 2f
NEG2 r_divdL
2:
XCALL __udivuha3
sbrs r0, 7 ; negate result if needed
ret
NEG2 r_quoL
ret
ENDF __divha3
#endif /* defined (L_divha3) */
#if defined (L_udivuha3)
DEFUN __udivuha3
mov r_quoH, r_divdL
mov r_divdL, r_divdH
clr r_divdH
lsl r_quoH ; shift quotient into carry
XJMP __udivuha3_common ; same as fractional after rearrange
ENDF __udivuha3
#endif /* defined (L_udivuha3) */
#undef r_divdL
#undef r_divdH
#undef r_quoL
#undef r_quoH
#undef r_divL
#undef r_divH
#undef r_cnt
/*******************************************************
Fixed Division 16.16 / 16.16
*******************************************************/
#define r_arg1L 24 /* arg1 gets passed already in place */
#define r_arg1H 25
#define r_arg1HL 26
#define r_arg1HH 27
#define r_divdL 26 /* dividend Low */
#define r_divdH 27
#define r_divdHL 30
#define r_divdHH 31 /* dividend High */
#define r_quoL 22 /* quotient Low */
#define r_quoH 23
#define r_quoHL 24
#define r_quoHH 25 /* quotient High */
#define r_divL 18 /* divisor Low */
#define r_divH 19
#define r_divHL 20
#define r_divHH 21 /* divisor High */
#define r_cnt __zero_reg__ /* loop count (0 after the loop!) */
#if defined (L_divsa3)
DEFUN __divsa3
mov r0, r_arg1HH
eor r0, r_divHH
sbrs r_divHH, 7
rjmp 1f
NEG4 r_divL
1:
sbrs r_arg1HH, 7
rjmp 2f
NEG4 r_arg1L
2:
XCALL __udivusa3
sbrs r0, 7 ; negate result if needed
ret
NEG4 r_quoL
ret
ENDF __divsa3
#endif /* defined (L_divsa3) */
#if defined (L_udivusa3)
DEFUN __udivusa3
ldi r_divdHL, 32 ; init loop counter
mov r_cnt, r_divdHL
clr r_divdHL
clr r_divdHH
wmov r_quoL, r_divdHL
lsl r_quoHL ; shift quotient into carry
rol r_quoHH
__udivusa3_loop:
rol r_divdL ; shift dividend (with CARRY)
rol r_divdH
rol r_divdHL
rol r_divdHH
brcs __udivusa3_ep ; dividend overflow
cp r_divdL,r_divL ; compare dividend & divisor
cpc r_divdH,r_divH
cpc r_divdHL,r_divHL
cpc r_divdHH,r_divHH
brcc __udivusa3_ep ; dividend >= divisor
rol r_quoL ; shift quotient (with CARRY)
rjmp __udivusa3_cont
__udivusa3_ep:
sub r_divdL,r_divL ; restore dividend
sbc r_divdH,r_divH
sbc r_divdHL,r_divHL
sbc r_divdHH,r_divHH
lsl r_quoL ; shift quotient (without CARRY)
__udivusa3_cont:
rol r_quoH ; shift quotient
rol r_quoHL
rol r_quoHH
dec r_cnt ; decrement loop counter
brne __udivusa3_loop
com r_quoL ; complement result
com r_quoH ; because C flag was complemented in loop
com r_quoHL
com r_quoHH
ret
ENDF __udivusa3
#endif /* defined (L_udivusa3) */
#undef r_arg1L
#undef r_arg1H
#undef r_arg1HL
#undef r_arg1HH
#undef r_divdL
#undef r_divdH
#undef r_divdHL
#undef r_divdHH
#undef r_quoL
#undef r_quoH
#undef r_quoHL
#undef r_quoHH
#undef r_divL
#undef r_divH
#undef r_divHL
#undef r_divHH
#undef r_cnt