pokecrystal/engine/math/math.asm

_Multiply::
; hMultiplier is one byte.
	ld a, 8
	ld b, a

	xor a
	ldh [hMultiplicand - 1], a
	ldh [hMathBuffer + 1], a
	ldh [hMathBuffer + 2], a
	ldh [hMathBuffer + 3], a
	ldh [hMathBuffer + 4], a

.loop
	ldh a, [hMultiplier]
	srl a
	ldh [hMultiplier], a
	jr nc, .next

	ldh a, [hMathBuffer + 4]
	ld c, a
	ldh a, [hMultiplicand + 2]
	add c
	ldh [hMathBuffer + 4], a

	ldh a, [hMathBuffer + 3]
	ld c, a
	ldh a, [hMultiplicand + 1]
	adc c
	ldh [hMathBuffer + 3], a

	ldh a, [hMathBuffer + 2]
	ld c, a
	ldh a, [hMultiplicand + 0]
	adc c
	ldh [hMathBuffer + 2], a

	ldh a, [hMathBuffer + 1]
	ld c, a
	ldh a, [hMultiplicand - 1]
	adc c
	ldh [hMathBuffer + 1], a

.next
	dec b
	jr z, .done

; hMultiplicand <<= 1

	ldh a, [hMultiplicand + 2]
	add a
	ldh [hMultiplicand + 2], a

	ldh a, [hMultiplicand + 1]
	rla
	ldh [hMultiplicand + 1], a

	ldh a, [hMultiplicand + 0]
	rla
	ldh [hMultiplicand + 0], a

	ldh a, [hMultiplicand - 1]
	rla
	ldh [hMultiplicand - 1], a

	jr .loop

.done
	ldh a, [hMathBuffer + 4]
	ldh [hProduct + 3], a

	ldh a, [hMathBuffer + 3]
	ldh [hProduct + 2], a

	ldh a, [hMathBuffer + 2]
	ldh [hProduct + 1], a

	ldh a, [hMathBuffer + 1]
	ldh [hProduct + 0], a

	ret

_Divide::
	xor a
	ldh [hMathBuffer + 0], a
	ldh [hMathBuffer + 1], a
	ldh [hMathBuffer + 2], a
	ldh [hMathBuffer + 3], a
	ldh [hMathBuffer + 4], a

	ld a, 9
	ld e, a

.loop
	ldh a, [hMathBuffer + 0]
	ld c, a
	ldh a, [hDividend + 1]
	sub c
	ld d, a

	ldh a, [hDivisor]
	ld c, a
	ldh a, [hDividend + 0]
	sbc c
	jr c, .next

	ldh [hDividend + 0], a

	ld a, d
	ldh [hDividend + 1], a

	ldh a, [hMathBuffer + 4]
	inc a
	ldh [hMathBuffer + 4], a

	jr .loop

.next
	ld a, b
	cp 1
	jr z, .done

	ldh a, [hMathBuffer + 4]
	add a
	ldh [hMathBuffer + 4], a

	ldh a, [hMathBuffer + 3]
	rla
	ldh [hMathBuffer + 3], a

	ldh a, [hMathBuffer + 2]
	rla
	ldh [hMathBuffer + 2], a

	ldh a, [hMathBuffer + 1]
	rla
	ldh [hMathBuffer + 1], a

	dec e
	jr nz, .next2

	ld e, 8
	ldh a, [hMathBuffer + 0]
	ldh [hDivisor], a
	xor a
	ldh [hMathBuffer + 0], a

	ldh a, [hDividend + 1]
	ldh [hDividend + 0], a

	ldh a, [hDividend + 2]
	ldh [hDividend + 1], a

	ldh a, [hDividend + 3]
	ldh [hDividend + 2], a

.next2
	ld a, e
	cp 1
	jr nz, .okay
	dec b

.okay
	ldh a, [hDivisor]
	srl a
	ldh [hDivisor], a

	ldh a, [hMathBuffer + 0]
	rr a
	ldh [hMathBuffer + 0], a

	jr .loop

.done
	ldh a, [hDividend + 1]
	ldh [hRemainder], a

	ldh a, [hMathBuffer + 4]
	ldh [hQuotient + 3], a

	ldh a, [hMathBuffer + 3]
	ldh [hQuotient + 2], a

	ldh a, [hMathBuffer + 2]
	ldh [hQuotient + 1], a

	ldh a, [hMathBuffer + 1]
	ldh [hQuotient + 0], a

	ret
Remove all address comments 2018-06-24 14:09:41 +00:00			`_Multiply::`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`; hMultiplier is one byte.`
			`ld a, 8`
			`ld b, a`

			`xor a`
hMultiplicand is four bytes internally, but the high byte is always 0 since allowing four-byte multiplicands could overflow hProduct. 2018-09-09 19:10:38 +00:00			`ldh [hMultiplicand - 1], a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 1], a`
			`ldh [hMathBuffer + 2], a`
			`ldh [hMathBuffer + 3], a`
			`ldh [hMathBuffer + 4], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
			`.loop`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMultiplier]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`srl a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMultiplier], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`jr nc, .next`

Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 4]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`ld c, a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMultiplicand + 2]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`add c`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 4], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 3]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`ld c, a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMultiplicand + 1]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`adc c`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 3], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 2]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`ld c, a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMultiplicand + 0]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`adc c`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 2], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 1]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`ld c, a`
hMultiplicand is four bytes internally, but the high byte is always 0 since allowing four-byte multiplicands could overflow hProduct. 2018-09-09 19:10:38 +00:00			`ldh a, [hMultiplicand - 1]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`adc c`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 1], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
			`.next`
			`dec b`
			`jr z, .done`

			`; hMultiplicand <<= 1`

Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMultiplicand + 2]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`add a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMultiplicand + 2], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMultiplicand + 1]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`rla`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMultiplicand + 1], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMultiplicand + 0]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`rla`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMultiplicand + 0], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
hMultiplicand is four bytes internally, but the high byte is always 0 since allowing four-byte multiplicands could overflow hProduct. 2018-09-09 19:10:38 +00:00			`ldh a, [hMultiplicand - 1]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`rla`
hMultiplicand is four bytes internally, but the high byte is always 0 since allowing four-byte multiplicands could overflow hProduct. 2018-09-09 19:10:38 +00:00			`ldh [hMultiplicand - 1], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
			`jr .loop`

			`.done`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 4]`
			`ldh [hProduct + 3], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 3]`
			`ldh [hProduct + 2], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 2]`
			`ldh [hProduct + 1], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 1]`
			`ldh [hProduct + 0], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
			`ret`

Remove all address comments 2018-06-24 14:09:41 +00:00			`_Divide::`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`xor a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 0], a`
			`ldh [hMathBuffer + 1], a`
			`ldh [hMathBuffer + 2], a`
			`ldh [hMathBuffer + 3], a`
			`ldh [hMathBuffer + 4], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
			`ld a, 9`
			`ld e, a`

			`.loop`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 0]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`ld c, a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hDividend + 1]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`sub c`
			`ld d, a`

Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hDivisor]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`ld c, a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hDividend + 0]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`sbc c`
			`jr c, .next`

Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hDividend + 0], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
			`ld a, d`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hDividend + 1], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 4]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`inc a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 4], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
			`jr .loop`

			`.next`
			`ld a, b`
			`cp 1`
			`jr z, .done`

Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 4]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`add a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 4], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 3]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`rla`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 3], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 2]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`rla`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 2], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 1]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`rla`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 1], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
			`dec e`
			`jr nz, .next2`

			`ld e, 8`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 0]`
			`ldh [hDivisor], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`xor a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 0], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hDividend + 1]`
			`ldh [hDividend + 0], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hDividend + 2]`
			`ldh [hDividend + 1], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hDividend + 3]`
			`ldh [hDividend + 2], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
			`.next2`
			`ld a, e`
			`cp 1`
			`jr nz, .okay`
			`dec b`

			`.okay`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hDivisor]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`srl a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hDivisor], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 0]`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00			`rr a`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh [hMathBuffer + 0], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
			`jr .loop`

			`.done`
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hDividend + 1]`
_Divide results go in hQuotient and hRemainder, not in hDividend and hDivisor Note that the result quotient is four bytes, but hQuotient is a three-byte buffer. This is because no Divide caller ever needed a four-byte quotient, so the buffer didn't include the high byte. 2018-08-26 02:58:26 +00:00			`ldh [hRemainder], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 4]`
hQuotient is a four-byte buffer (fixes #558) 2018-08-26 17:49:38 +00:00			`ldh [hQuotient + 3], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 3]`
hQuotient is a four-byte buffer (fixes #558) 2018-08-26 17:49:38 +00:00			`ldh [hQuotient + 2], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 2]`
hQuotient is a four-byte buffer (fixes #558) 2018-08-26 17:49:38 +00:00			`ldh [hQuotient + 1], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
Use labels instead of constants for HRAM Use explicit ldh instruction to access HRAM locations, don't rely on optimizing ld 2018-08-25 18:28:22 +00:00			`ldh a, [hMathBuffer + 1]`
hQuotient is a four-byte buffer (fixes #558) 2018-08-26 17:49:38 +00:00			`ldh [hQuotient + 0], a`
Renaming sections, further dissolving main.asm 2015-11-28 20:13:40 +00:00
			`ret`