239 lines
6.3 KiB
NASM
239 lines
6.3 KiB
NASM
mcopy dag.macros
|
|
****************************************************************
|
|
*
|
|
* function udiv(x,y: longint): longint;
|
|
*
|
|
* Inputs:
|
|
* num1 - numerator
|
|
* num2 - denominator
|
|
*
|
|
* Outputs:
|
|
* ans - result
|
|
*
|
|
****************************************************************
|
|
*
|
|
udiv start
|
|
ans equ 0 answer
|
|
rem equ 4 remainder
|
|
|
|
subroutine (4:num1,4:num2),8
|
|
;
|
|
; Initialize
|
|
;
|
|
stz rem rem = 0
|
|
stz rem+2
|
|
move4 num1,ans ans = num1
|
|
lda num2 check for division by zero
|
|
ora num2+2
|
|
beq dv9
|
|
|
|
lda num2+2 do 16 bit divides separately
|
|
ora ans+2
|
|
beq dv5
|
|
;
|
|
; 32 bit divide
|
|
;
|
|
ldy #32 32 bits to go
|
|
dv3 asl ans roll up the next number
|
|
rol ans+2
|
|
rol ans+4
|
|
rol ans+6
|
|
sec subtract for this digit
|
|
lda ans+4
|
|
sbc num2
|
|
tax
|
|
lda ans+6
|
|
sbc num2+2
|
|
bcc dv4 branch if minus
|
|
stx ans+4 turn the bit on
|
|
sta ans+6
|
|
inc ans
|
|
dv4 dey next bit
|
|
bne dv3
|
|
bra dv9 go do the sign
|
|
;
|
|
; 16 bit divide
|
|
;
|
|
dv5 lda #0 initialize the remainder
|
|
ldy #16 16 bits to go
|
|
dv6 asl ans roll up the next number
|
|
rol a
|
|
sec subtract the digit
|
|
sbc num2
|
|
bcs dv7
|
|
adc num2 digit is 0
|
|
dey
|
|
bne dv6
|
|
bra dv8
|
|
dv7 inc ans digit is 1
|
|
dey
|
|
bne dv6
|
|
|
|
dv8 sta ans+4 save the remainder
|
|
;
|
|
; Return the result
|
|
;
|
|
dv9 return 4:ans move answer
|
|
end
|
|
|
|
****************************************************************
|
|
*
|
|
* function umod(x,y: longint): longint;
|
|
*
|
|
* Inputs:
|
|
* num1 - numerator
|
|
* num2 - denominator
|
|
*
|
|
* Outputs:
|
|
* ans+4 - result
|
|
*
|
|
****************************************************************
|
|
*
|
|
umod start
|
|
ans equ 0 answer
|
|
rem equ 4 remainder
|
|
|
|
subroutine (4:num1,4:num2),8
|
|
;
|
|
; Initialize
|
|
;
|
|
stz rem rem = 0
|
|
stz rem+2
|
|
move4 num1,ans ans = num1
|
|
lda num2 check for division by zero
|
|
ora num2+2
|
|
beq dv9
|
|
|
|
lda num2+2 do 16 bit divides separately
|
|
ora ans+2
|
|
beq dv5
|
|
;
|
|
; 32 bit divide
|
|
;
|
|
ldy #32 32 bits to go
|
|
dv3 asl ans roll up the next number
|
|
rol ans+2
|
|
rol ans+4
|
|
rol ans+6
|
|
sec subtract for this digit
|
|
lda ans+4
|
|
sbc num2
|
|
tax
|
|
lda ans+6
|
|
sbc num2+2
|
|
bcc dv4 branch if minus
|
|
stx ans+4 turn the bit on
|
|
sta ans+6
|
|
inc ans
|
|
dv4 dey next bit
|
|
bne dv3
|
|
bra dv9 go do the sign
|
|
;
|
|
; 16 bit divide
|
|
;
|
|
dv5 lda #0 initialize the remainder
|
|
ldy #16 16 bits to go
|
|
dv6 asl ans roll up the next number
|
|
rol a
|
|
sec subtract the digit
|
|
sbc num2
|
|
bcs dv7
|
|
adc num2 digit is 0
|
|
dey
|
|
bne dv6
|
|
bra dv8
|
|
dv7 inc ans digit is 1
|
|
dey
|
|
bne dv6
|
|
|
|
dv8 sta ans+4 save the remainder
|
|
;
|
|
; Return the result
|
|
;
|
|
dv9 return 4:ans+4 move answer
|
|
end
|
|
|
|
****************************************************************
|
|
*
|
|
* function umul(x,y: longint): longint;
|
|
*
|
|
* Inputs:
|
|
* num2,num1 - operands
|
|
*
|
|
* Outputs:
|
|
* ans - result
|
|
*
|
|
****************************************************************
|
|
*
|
|
umul start
|
|
ans equ 0 answer
|
|
|
|
subroutine (4:num1,4:num2),8
|
|
;
|
|
; Initialize the sign and split on precision.
|
|
;
|
|
stz ans+4 set up the multiplier
|
|
stz ans+6
|
|
lda num1
|
|
sta ans
|
|
lda num1+2
|
|
sta ans+2
|
|
beq ml3 branch if the multiplier is 16 bit
|
|
;
|
|
; Do a 32 bit by 32 bit multiply.
|
|
;
|
|
ldy #32 32 bit multiply
|
|
jsr ml1
|
|
brl ml7
|
|
|
|
ml1 lda ans SYSS1*SYSS1+2+SYSS1+2 -> SYSS1,SYSS1+2
|
|
lsr a
|
|
bcc ml2
|
|
clc add multiplicand to the partial product
|
|
lda ans+4
|
|
adc num2
|
|
sta ans+4
|
|
lda ans+6
|
|
adc num2+2
|
|
sta ans+6
|
|
ml2 ror ans+6 shift the interem result
|
|
ror ans+4
|
|
ror ans+2
|
|
ror ans
|
|
dey loop til done
|
|
bne ml1
|
|
rts
|
|
;
|
|
; Do and 16 bit by 32 bit multiply.
|
|
;
|
|
ml3 lda num2+2 branch if 16x16 is possible
|
|
beq ml4
|
|
|
|
ldy #16 set up for 16 bits
|
|
jsr ml1 do the multiply
|
|
lda ans+2 move the answer
|
|
sta ans
|
|
lda ans+4
|
|
sta ans+2
|
|
bra ml7
|
|
;
|
|
; Do a 16 bit by 16 bit multiply.
|
|
;
|
|
ml4 ldy #16 set the 16 bit counter
|
|
ldx ans move the low word
|
|
stx ans+2
|
|
ml5 lsr ans+2 test the bit
|
|
bcc ml6 branch if the bit is off
|
|
clc
|
|
adc num2
|
|
ml6 ror a shift the answer
|
|
ror ans
|
|
dey loop
|
|
bne ml5
|
|
sta ans+2 save the high word
|
|
;
|
|
; Return the result.
|
|
;
|
|
ml7 return 4:ans fix the stack
|
|
end
|