X-Git-Url: https://git.gir.st/Chiptunes.git/blobdiff_plain/fe9a76e40a40c815efac4bfb99d7105d9c94dda6..362b33c918938aadd44c6516c15661c30952a584:/foo.c

diff --git a/foo.c b/foo.c
index ef4720b..fcb07cd 100644
--- a/foo.c
+++ b/foo.c
@@ -1,19 +1,235 @@
 #include <stdio.h>
+#include "fakeasm.h"
 typedef unsigned char u8;
-int g(int i, int x, int t, int o) {
-	return ((3 & x & (i * ((3 & i >> 16 ? "BY}6YB6%" : "Qj}6jQ6%")[t % 8] + 51) >> o)) << 4);
+
+u8 data[] = {   
+	0x84, 0x9d, 0xb0, 0x69, 0x9d, 0x84, 0x69, 0x58,
+	0x75, 0x8c, 0xb0, 0x69, 0x8c, 0x75, 0x69, 0x58
+};
+u8 zero; //zero register
+u8 i0;
+u8 i1;
+u8 i2;
+u8 i3;
+u8 x;
+u8 t;
+u8 o;
+u8 _;
+#define Mh o //mod3 vars
+#define Ml t // -"-
+//http://homepage.divms.uiowa.edu/~jones/bcd/mod.shtml
+void mod3(void) {
+	// mod3(Mh.Ml) -> t
+	#define tmp _
+	ADD	(Ml, Mh)
+	CLR	(Mh)
+	ADC	(Mh, zero, carry) //Mh only holds the carry bit
+	MOV	(tmp, Ml)
+	SWAP	(tmp)
+	ANDI	(tmp, 0x0f)
+	SWAP	(Mh)
+	OR	(tmp, Mh)
+	ANDI	(Ml, 0x0f)
+	ADD	(Ml, tmp)
+	MOV	(tmp, Ml)
+	LSR	(tmp)
+	LSR	(tmp)
+	ANDI	(Ml, 0x03)
+	ADD	(Ml, tmp)
+	MOV	(tmp, Ml)
+	LSR	(tmp)
+	LSR	(tmp)
+	ANDI	(Ml, 0x03)
+	ADD	(Ml, tmp)
+	CPI	(Ml, 3)
+	BRPL	(skip)
+	SUBI	(Ml, 3)
+	skip:;
+	RET
+	#undef tmp
+}
+void g(void) {
+	// g(i, t) -> t
+	// tempvars: `x` and `_`
+	#define tmp _
+	ANDI	(t, 0x07)
+	MOV	(tmp, i2)
+	ANDI	(tmp, 3)
+	TST	(tmp)
+	#undef tmp
+	BREQ	(skip)
+	SUBI	(t, -8)
+	skip:
+	t = data[t];
+	/*MOV X_hi==_, data_hi
+	  MOV X_lo==t, data_lo
+	  ADD X_lo, t
+	  ADC X_hi, zero
+	  LD  t, X         */
+	t = (((i1&0x1f)<<8|i0)*t)>>8; //TODO
+	RET //TODO: CALL/RET is expensive; store PC in register and RJMP, then JRMP back
 };
 
 int main(void) {
-	int i;
-	int n;
-	int s;
-	for (i = 0;; i++) {
-		n = i >> 14;
-		s = i >> 17;
-		putchar(g(i, 1, n, 12) +
-			g(i, s, n ^ i >> 13, 10) + 
-			g(i, s / 3, n + ((i >> 11) % 3), 10) + 
-			g(i, s / 5, 8 + n - ((i >> 10) % 3), 9));
+	u8 n;
+	u8 s;
+	u8 acc;
+	//TODO: clear all vars/registers
+	for (;;) {
+		MOV	(n, i2)
+		LSL	(n)
+		LSL	(n)
+		#define tmp acc
+		MOV	(tmp, i1)
+		SWAP	(tmp)
+		ANDI	(tmp, 0x0f)
+		LSR	(tmp)
+		LSR	(tmp)
+		OR	(n, tmp)
+		#undef tmp
+		MOV	(s, i3)
+		ROR	(s)
+		ROR	(s)
+		ANDI	(s, 0x80)
+		#define tmp acc
+		MOV	(tmp, i2)
+		LSR	(tmp)
+		OR	(s, tmp)
+		#undef tmp
+
+		//voice 1:
+		MOV	(t, n)
+		LDI	(o, 4)
+		RCALL	g();
+	t >>= o; //NOTE: o == {1, 2, 4}
+	ANDI	(t, 3)
+		ANDI	(t, 1)
+		MOV	(acc, t)
+
+		//voice 2:
+		#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, 2)
+		RCALL	g();
+	t >>= o; //NOTE: o == {1, 2, 4}
+	ANDI	(t, 3)
+		AND	(t, s)
+		ADD	(acc, t)
+
+		//voice 3:
+		MOV	(Ml, i2)
+		SWAP	(Ml)
+		ANDI	(Ml, 0xf0)
+		LSL	(Ml)
+		#define tmp Mh
+		MOV	(tmp, i1)
+		LSR	(tmp)
+		LSR	(tmp)
+		LSR	(tmp)
+		OR	(Ml, tmp)
+		#undef tmp
+		MOV	(Mh, i3)
+		SWAP	(Mh)
+		ANDI	(Mh, 0xf0)
+		LSL	(Mh)
+		#define tmp _
+		MOV	(tmp, i2)
+		LSR	(tmp)
+		LSR	(tmp)
+		LSR	(tmp)
+		OR	(Mh, tmp)
+		#undef tmp
+		RCALL	mod3();
+		ADD	(t, n)
+		LDI	(o, 2)
+		RCALL	g();
+	t >>= o; //NOTE: o == {1, 2, 4}
+	ANDI	(t, 3)
+		MOV	(x, s)
+		INC	(x)
+		#define tmp o
+		MOV	(tmp, x)
+		LSR	(tmp)
+		LSR	(tmp)
+		ADD	(tmp, x)
+		ROR	(tmp)
+		LSR	(tmp)
+		ADD	(tmp, x)
+		ROR	(tmp)
+		LSR	(tmp)
+		ADD	(tmp, x)
+		ROR	(tmp)
+		LSR	(tmp)
+                MOV	(x, tmp)
+		#undef tmp
+		AND	(t, x)
+		ADD	(acc, t)
+
+		//voice 4:
+		MOV	(Ml, i2)
+		SWAP	(Ml)
+		ANDI	(Ml, 0xf0)
+		LSL	(Ml)
+		LSL	(Ml)
+		#define tmp Mh
+		MOV	(tmp, i1)
+		LSR	(tmp)
+		LSR	(tmp)
+		OR	(Ml, tmp)
+		#undef tmp
+		MOV	(Mh, i3)
+		SWAP	(Mh)
+		ANDI	(Mh, 0xf0)
+		LSL	(Mh)
+		LSL	(Mh)
+		#define tmp _
+		MOV	(tmp, i2)
+		LSR	(tmp)
+		LSR	(tmp)
+		OR	(Mh, tmp)
+		#undef tmp
+		RCALL	mod3();
+		SUB	(t, n)
+		NEG	(t)
+		SUBI	(t, -8)
+		LDI	(o, 1)
+		RCALL	g();
+	t >>= o; //NOTE: o == {1, 2, 4}
+	ANDI	(t, 3)
+		MOV	(x, s)
+		INC	(x)
+		#define tmp o
+                MOV	(tmp, x)
+		LSR	(tmp)
+                ADD	(tmp, x)
+		ROR	(tmp)
+		LSR	(tmp)
+		LSR	(tmp)
+                ADD	(tmp, x)
+		ROR	(tmp)
+                ADD	(tmp, x)
+		ROR	(tmp)
+		LSR	(tmp)
+		LSR	(tmp)
+                MOV	(x, tmp)
+		#undef tmp
+		AND	(t, x)
+		ADD	(acc, t)
+
+		putchar(acc<<4); //TODO
+		SUBI	(i0, -1)
+		ADC	(i1, zero, !i0)
+		ADC	(i2, zero, !i0&&!i1)
+		ADC	(i3, zero, !i0&&!i1&&!i2)
 	}
 }