First Commit

Upload literally everything from the pokecrystal16 expand-move-ID branch

home/indirection.asm

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+LoadIndirectPointer::
+	; in: a:hl: indirect table, bc: index
+	; out: a:hl: pointer to element, b: copy of a, c: clobbered, de: preserved, zero flag: set if pointer is null
+	push de
+	ld d, a
+	ldh a, [hROMBank]
+	push af
+	ld a, d
+	rst Bankswitch
+	ld a, [hli]
+	ld e, a
+	ld a, [hli]
+	ld d, a
+	add a, a
+	jr nc, .loop
+	res 7, d
+	dec bc
+	ld a, b
+	and c
+	inc a
+	jr nz, .loop
+.null
+	ld hl, 0
+	ld b, h
+.done
+	pop af
+	rst Bankswitch
+	pop de
+	ld a, h
+	or l
+	ld a, b
+	ret
+
+.next
+	inc hl
+	inc hl
+	inc hl
+	cpl
+	inc a
+	add a, c
+	ld c, a
+	jr c, .loop ;subtracting by addition has the carry flipped
+	dec b
+.loop
+	ld a, [hli]
+	and a
+	jr z, .null
+	inc b
+	dec b
+	jr nz, .next
+	cp c
+	jr c, .next
+	jr z, .next
+
+	ld a, [hli]
+	ld b, a
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	or h
+	jr z, .done ;no point in setting them to zero if they already are
+	ld a, c
+	ld c, e
+	ld e, b
+	ld b, d
+	call AddNTimes
+	ld b, e
+	jr .done
+
+LoadDoubleIndirectPointer::
+	; for indirect tables of near pointers to data, used for structures of varying size
+	; same calling convention as LoadIndirectPointer
+	call LoadIndirectPointer
+	call nz, GetFarWord
+	ld a, b
+	ret