git.y1.nz

commit 05a81b7d4cdc70ad8adda5e2bbc8c800e7d0cdc5
parent 6ccf4819003e8880b9c74043afda55a7f7fd89fd
Author: toxa <untoxa@mail.ru>
Date:   Thu,  5 Nov 2020 18:08:38 +0300

hiramcpy() minor optimizations

Diffstat:
D
gbdk-lib/libc/gb/backup/get_xy_t.s
75
---------------------------------------------------------------------------
M
gbdk-lib/libc/gb/hiramcpy.s
38
++++++++++++++++++--------------------

2 files changed, 18 insertions(+), 95 deletions(-)
diff --git a/gbdk-lib/libc/gb/backup/get_xy_t.s b/gbdk-lib/libc/gb/backup/get_xy_t.s
@@ -1,75 +0,0 @@
-	.include        "global.s"
-
-	;; BANKED:	checked
-	.area	_BASE
-
-	;; Store window tile table into (BC) at xy = DE of size WH = HL
-	;; WH >= (1,1)
-.get_xy_wtt::
-	PUSH	HL		; Store WH
-	PUSH	HL		; Store WH
-	LDH	A,(.LCDC)
-	BIT	6,A
-	JR	NZ,1$
-	LD	HL,#0x9800	; HL = origin
-	JR	.get_xy_tt
-1$:
-	LD	HL,#0x9C00	; HL = origin
-	JR	.get_xy_tt
-	;; Store background tile table into (BC) at XY = DE of size WH = HL
-	;; WH >= (1,1)
-.get_xy_btt::
-	PUSH	HL		; Store WH
-	LDH	A,(.LCDC)
-	BIT	3,A
-	JR	NZ,1$
-	LD	HL,#0x9800	; HL = origin
-	JR	.get_xy_tt
-1$:
-	LD	HL,#0x9C00	; HL = origin
-;	JR	.get_xy_tt
-
-.get_xy_tt::
-	PUSH	BC		; Store source
-	XOR	A
-	OR	E
-	JR	Z,2$
-
-	LD	BC,#0x20	; One line is 20 tiles
-1$:
-	ADD	HL,BC		; Y coordinate
-	DEC	E
-	JR	NZ,1$
-2$:
-	LD	B,#0x00		; X coordinate
-	LD	C,D
-	ADD	HL,BC
-
-	POP	BC		; BC = source
-	POP	DE		; DE = WH
-	PUSH	HL		; Store origin
-	PUSH	DE		; Store WH
-3$:
-	WAIT_STAT
-
-	LD	A,(HL+)		; Copy W tiles
-	LD	(BC),A
-	INC	BC
-	DEC	D
-	JR	NZ,3$
-	POP	HL		; HL = WH
-	LD	D,H		; Restore D = W
-	POP	HL		; HL = origin
-	DEC	E
-	JR	Z,4$
-
-	PUSH	BC		; Next line
-	LD	BC,#0x20	; One line is 20 tiles
-	ADD	HL,BC
-	POP	BC
-
-	PUSH	HL		; Store current origin
-	PUSH	DE		; Store WH
-	JR	3$
-4$:
-	RET
diff --git a/gbdk-lib/libc/gb/hiramcpy.s b/gbdk-lib/libc/gb/hiramcpy.s
@@ -3,35 +3,33 @@
 	;; BANKED:	checked
 	.area	_BASE
 
+_hiramcpy::
+	LDA	HL,4(SP)	; Skip return address and registers
+	LD	E,(HL)		; E = dst
+	LDA	HL,7(SP)
+	LD	A,(HL-)
+	LD	D, A		; D = n
+	LD	A,(HL-)		; HL = src
+	LD	L,(HL)
+	LD	H,A
+
 	;; Copy memory zone to HIRAM
 	;; 
 	;; Entry conditions
-	;;   C = destination
-	;;   B = length
+	;;   E = destination
+	;;   D = length
 	;;   HL = source
 	;; 
-	;; Register used: AF, BC, HL
+	;; Preserves: BC
 .hiramcpy::
+	LD	A,E
+	LD	E,C
+	LD	C,A
 1$:
 	LD	A,(HL+)
 	LDH	(C),A
 	INC	C
-	DEC	B
+	DEC	D
 	JR	NZ,1$
-	RET
-
-_hiramcpy::
-	PUSH	BC
-
-	LDA	HL,4(SP)	; Skip return address and registers
-	LD	C,(HL)		; C = dst
-	LDA	HL,7(SP)
-	LD	A,(HL-)		; B = n
-	LD	B, A
-	LD	A,(HL-)		; HL = src
-	LD	L,(HL)
-	LD	H,A
-	CALL	.hiramcpy
-
-	POP	BC
+	LD	C,E
 	RET

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