X-Git-Url: https://git.gir.st/Chiptunes.git/blobdiff_plain/9548359dac06fb8976b9a6bb35d66e8a122a079f..44e34da036f83d3efd6384cdc37ec9bd3e234e3a:/foo.c

diff --git a/foo.c b/foo.c
index 1d9ade9..c2bcb5d 100644
--- a/foo.c
+++ b/foo.c
@@ -15,7 +15,7 @@ u8 i3;		//r21
 u8 n;		//r22
 u8 s;		//r23
 u8 _;		//r24
-		//r25
+u8 loop;	//r25
 u8 t;/*==Ml*/	//r26 (Xlo)
 u8 x;/*==Mh*/	//r27 (Xhi)
 		//r28
@@ -55,6 +55,219 @@ void mod3(void) {
 	RET
 	#undef tmp
 }
+void mul(void) { //don't need overhead of function (inline it)
+	// i1.i0 * t -> _.x.t
+	#define a1 x
+	#define a2 _
+	#define a0 t
+	// start MUL -- 92 cycles :( (unrolled and skipping second bit: 76)
+	CLR	(a2)
+	CLR	(a1)
+
+	CPI	(t, 0x58)
+	BREQ	(mul_58)
+	CPI	(t, 0x69)
+	BREQ	(mul_69)
+	CPI	(t, 0x75)
+	BREQ	(mul_75)
+	CPI	(t, 0x84)
+	BREQ	(mul_84)
+	CPI	(t, 0x8c)
+	BREQ	(mul_8c)
+	CPI	(t, 0x9d)
+	BREQ	(mul_9d)
+	CPI	(t, 0xb0)
+	BREQ	(mul_b0)
+	mul_58: // 0101 1000
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		RJMP	(endmul)
+	mul_69: // 0110 1001
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		RJMP	(endmul)
+	mul_75: // 0111 0101
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		RJMP	(endmul)
+	mul_84: // 1000 0100
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		RJMP	(endmul)
+	mul_8c: // 1000 1100
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		RJMP	(endmul)
+	mul_9d: // 1001 1101
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		RJMP	(endmul)
+	mul_b0: // 1011 0000
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+		LSR (a2)
+		ROR (a1)
+		ADD (a1, i0)
+		ADC (a2, i1, carry)
+		LSR (a2)
+		ROR (a1)
+	endmul:
+
+	// end MUL
+	#undef a0
+	#undef a1
+	#undef a2
+	RET
+}
 void g(void) {
 	// g(i, t) -> t
 	// tempvars: `x` and `_`
@@ -73,9 +286,8 @@ void g(void) {
 	  ADD X_lo, t
 	  ADC X_hi, zero
 	  LD  t, X         */
-	t &= 0xfd; //hint
-	t = (((i1&0x1f)<<8|i0)*t)>>8; //TODO
-	t &= 0x1e; //hint
+	RCALL	mul(); //stores used value in in x
+	MOV	(t, x)
 	RET //TODO: replace CALL/RET with IJMP?
 };
 
@@ -111,6 +323,7 @@ int main(void) {
 		MOV	(t, n)
 		RCALL	g();
 		SWAP	(t)
+		ANDI	(t, 1)
 		MOV	(acc, t)
 
 		//voice 2: