X-Git-Url: https://git.gir.st/Chiptunes.git/blobdiff_plain/bfce2f8ca313a3a739c6a565d4af9650354960b7..5d4207f9a0b24eec52054fa1674cded926f06a72:/foo.c

diff --git a/foo.c b/foo.c
index 46d2d30..4caddea 100644
--- a/foo.c
+++ b/foo.c
@@ -6,59 +6,94 @@ u8 data[] = {
 	0x84, 0x9d, 0xb0, 0x69, 0x9d, 0x84, 0x69, 0x58,
 	0x75, 0x8c, 0xb0, 0x69, 0x8c, 0x75, 0x69, 0x58
 };
+u8 i0;
+u8 i1;
+u8 i2;
+u8 i3;
 u8 x;
 u8 t;
 u8 o;
-u8 g(int i) {
+void g(void) {
+	// g(i, x, t, o) -> t
 	u8 tmp;
 	ANDI	(t, 0x07)
-	tmp = i >> 16;
+	MOV	(tmp, i2)
 	ANDI	(tmp, 3)
 	TST	(tmp)
 	BREQ	(skip)
 	SUBI	(t, -8)
 	skip:
 	t = data[t];
-	t = (i*t) >> o;
+	t = ((i3<<24|i2<<16|i1<<8|i0)*t) >> o;
 	AND	(t, x)
 	ANDI	(t, 3)
-	return t;
+	RET
 };
 
 int main(void) {
-	int i;
-	unsigned short n;
-	unsigned short s;
+	u8 n;
+	u8 s;
 	u8 acc;
-	for (i = 0;; i++) {
-		acc = 0;
-		n = i >> 14;
-		s = i >> 17;
+	//TODO: clear all vars/registers
+	for (;;) {
+		MOV	(n, i2)
+		LSL	(n)
+		LSL	(n)
+		#define tmp acc
+		MOV	(tmp, i1)
+		SWAP	(tmp)
+		ANDI	(tmp, 0x0f)
+		tmp >>= 2;
+		OR	(n, tmp)
+		#undef tmp
+		s = (i3<<7 | i2>>1);
 
 		//voice 1:
 		LDI	(x, 1)
 		MOV	(t, n)
 		LDI	(o, 12)
-		acc += g(i);
+		RCALL	g();
+		MOV	(acc, t)
 
 		//voice 2:
 		MOV	(x, s)
-		t = n ^ i >> 13;
+		#define tmp o
+		MOV	(tmp, i2)
+		LSL	(tmp)
+		LSL	(tmp)
+		LSL	(tmp)
+		MOV	(t, i1)
+		SWAP	(t)
+		ANDI	(t, 0xf)
+		LSR	(t)
+		OR	(t, tmp)
+		#undef tmp
+		EOR	(t, n)
 		LDI	(o, 10)
-		acc += g(i);
+		RCALL	g();
+		ADD	(acc, t)
 
 		//voice 3:
 		x = s / 3;
-		t = n + ((i >> 11) % 3);
+		t = n + ((i3<<13 | i2<<5 | i1>>3) % 3);
 		LDI	(o, 10)
-		acc += g(i);
+		RCALL	g();
+		ADD	(acc, t)
 
 		//voice 4:
 		x = s / 5;
-		t = 8 + n - ((i >> 10) % 3);
+		t = 8 + n - ((i3<<14 | i2<<6 | i1>>2) % 3);
 		LDI	(o, 9)
-		acc += g(i);
+		RCALL	g();
+		ADD	(acc, t)
 
 		putchar(acc<<4);
+		#define tmp acc
+		LDI	(tmp, 0)
+		SUBI	(i0, -1)
+		ADC	(i1, tmp, !i0)
+		ADC	(i2, tmp, !i0&&!i1)
+		ADC	(i3, tmp, !i0&&!i1&&!i2)
+		#undef tmp
 	}
 }