From cb1dcd12ebc97e79d0c663d5ef96c3bbbc8c0733 Mon Sep 17 00:00:00 2001
From: neauoire <aliceffekt@gmail.com>
Date: Mon, 7 Aug 2023 16:28:41 -0700
Subject: [PATCH] Returned the simpler uxn core, connected to device masks

---
 src/devices/screen.c |  35 ++++++----
 src/uxn.c            | 158 +++++++++++++++++--------------------------
 src/uxn.h            |   2 +
 3 files changed, 83 insertions(+), 112 deletions(-)

diff --git a/src/devices/screen.c b/src/devices/screen.c
index 93809e7..7c2f81c 100644
--- a/src/devices/screen.c
+++ b/src/devices/screen.c
@@ -46,6 +46,24 @@ screen_fill(Uint8 *layer, int x1, int y1, int x2, int y2, int color)
 			layer[x + y * width] = color;
 }
 
+static void
+screen_blit(Uint8 *layer, Uint8 *ram, Uint16 addr, int x1, int y1, int color, int flipx, int flipy, int twobpp)
+{
+	int v, h, width = uxn_screen.width, height = uxn_screen.height, opaque = (color % 5);
+	for(v = 0; v < 8; v++) {
+		Uint16 c = ram[(addr + v) & 0xffff] | (twobpp ? (ram[(addr + v + 8) & 0xffff] << 8) : 0);
+		Uint16 y = y1 + (flipy ? 7 - v : v);
+		for(h = 7; h >= 0; --h, c >>= 1) {
+			Uint8 ch = (c & 1) | ((c >> 7) & 2);
+			if(opaque || ch) {
+				Uint16 x = x1 + (flipx ? 7 - h : h);
+				if(x < width && y < height)
+					layer[x + y * width] = blending[ch][color];
+			}
+		}
+	}
+}
+
 void
 screen_palette(Uint8 *addr)
 {
@@ -167,28 +185,15 @@ screen_deo(Uint8 *ram, Uint8 *d, Uint8 port)
 		Uint8 length = move >> 4;
 		Uint8 twobpp = !!(ctrl & 0x80);
 		Uint8 *layer = (ctrl & 0x40) ? uxn_screen.fg : uxn_screen.bg;
-		Uint8 color = ctrl & 0xf, opaque = color % 5;
+		Uint8 color = ctrl & 0xf;
 		Uint16 x = PEEK2(d + 0x8), dx = (move & 0x1) << 3;
 		Uint16 y = PEEK2(d + 0xa), dy = (move & 0x2) << 2;
 		Uint16 addr = PEEK2(d + 0xc), addr_incr = (move & 0x4) << (1 + twobpp);
 		int flipx = (ctrl & 0x10), fx = flipx ? -1 : 1;
 		int flipy = (ctrl & 0x20), fy = flipy ? -1 : 1;
-		int v, h, width = uxn_screen.width, height = uxn_screen.height;
 		Uint16 dyx = dy * fx, dxy = dx * fy;
 		for(i = 0; i <= length; i++) {
-			Uint16 x1 = x + dyx * i, y1 = y + dxy * i;
-			for(v = 0; v < 8; v++) {
-				Uint16 c = ram[(addr + v) & 0xffff] | (twobpp ? (ram[(addr + v + 8) & 0xffff] << 8) : 0);
-				Uint16 y = y1 + (flipy ? 7 - v : v);
-				for(h = 7; h >= 0; --h, c >>= 1) {
-					Uint8 ch = (c & 1) | ((c >> 7) & 2);
-					if(opaque || ch) {
-						Uint16 x = x1 + (flipx ? 7 - h : h);
-						if(x < width && y < height)
-							layer[x + y * width] = blending[ch][color];
-					}
-				}
-			}
+			screen_blit(layer, ram, addr, x + dyx * i, y + dxy * i, color, flipx, flipy, twobpp);
 			addr += addr_incr;
 		}
 		screen_change(x, y, x + dyx * length + 8, y + dxy * length + 8);
diff --git a/src/uxn.c b/src/uxn.c
index 8f5e58e..46c0d8b 100644
--- a/src/uxn.c
+++ b/src/uxn.c
@@ -11,113 +11,77 @@ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 WITH REGARD TO THIS SOFTWARE.
 */
 
-/* Registers
-[ . ][ . ][ . ][ L ][ N ][ T ] <
-[ . ][ . ][ . ][   H2   ][ T ] <
-[   L2   ][   N2   ][   T2   ] <
-*/
-
-#define T s->dat[s->ptr - 1]
-#define N s->dat[s->ptr - 2]
-#define L s->dat[s->ptr - 3]
-#define T2 PEEK2(s->dat + s->ptr - 2)
-#define H2 PEEK2(s->dat + s->ptr - 3)
-#define N2 PEEK2(s->dat + s->ptr - 4)
-#define L2 PEEK2(s->dat + s->ptr - 6)
-
 #define HALT(c)    { return emu_halt(u, ins, (c), pc - 1); }
-#define FLIP       { s = ins & 0x40 ? &u->wst : &u->rst; }
-#define SET(x, y)  { if(x > s->ptr) HALT(1) tmp = (x & k) + y + s->ptr; if(tmp > 254) HALT(2) s->ptr = tmp; }
-#define PUT(o, v)  { s->dat[(s->ptr - 1 - (o))] = (v); }
-#define PUT2(o, v) { tmp = (v); POKE2(s->dat + (s->ptr - o - 2), tmp); }
-#define DEO(a, b)  { u->dev[(a)] = (b); if((deo_mask[(a) >> 4] >> ((a) & 0xf)) & 0x1) emu_deo(u, (a)); }
-#define DEI(a, b)  { PUT((a), ((dei_mask[(b) >> 4] >> ((b) & 0xf)) & 0x1) ? emu_dei(u, (b)) : u->dev[(b)]) }
+#define FLIP       { s = (ins & 0x40) ? &u->wst : &u->rst; }
+#define JUMP(x)    { if(m2) pc = (x); else pc += (Sint8)(x); }
+#define POKE(x, y) { if(m2) { POKE2(ram + x, y) } else { ram[(x)] = (y); } }
+#define PEEK(o, x) { if(m2) { o = PEEK2(ram + x); } else o = ram[(x)]; }
+#define PUSH1(y)   { if(s->ptr == 0xff) HALT(2) s->dat[s->ptr++] = (y); }
+#define PUSH2(y)   { if((tsp = s->ptr) >= 0xfe) HALT(2) t = (y); POKE2(&s->dat[tsp], t); s->ptr = tsp + 2; }
+#define PUSHx(y)   { if(m2) { PUSH2(y) } else { PUSH1(y) } }
+#define POP1(o)    { if(*sp == 0x00) HALT(1) o = s->dat[--*sp]; }
+#define POP2(o)    { if((tsp = *sp) <= 0x01) HALT(1) o = PEEK2(&s->dat[tsp - 2]); *sp = tsp - 2; }
+#define POPx(o)    { if(m2) { POP2(o) } else { POP1(o) } }
+#define DEVW(p, y) { if(m2) { DEO(p, y >> 8) DEO((p + 1), y) } else { DEO(p, y) } }
+#define DEVR(o, p) { if(m2) { o = ((DEI(p) << 8) + DEI(p + 1)); } else { o = DEI(p); } }
 
 int
 uxn_eval(Uxn *u, Uint16 pc)
 {
-	int t, n, l, k, tmp, ins, opc;
-	Uint8 *ram = u->ram;
+	Uint8 ins, opc, m2, ksp, tsp, *sp, *ram = u->ram;
+	Uint16 a, b, c, t;
 	Stack *s;
 	if(!pc || u->dev[0x0f]) return 0;
 	for(;;) {
 		ins = ram[pc++];
-		k = ins & 0x80 ? 0xff : 0;
+		/* modes */
+		opc = ins & 0x1f;
+		m2 = ins & 0x20;
 		s = ins & 0x40 ? &u->rst : &u->wst;
-		opc = !(ins & 0x1f) ? (0 - (ins >> 5)) & 0xff : ins & 0x3f;
-		switch(opc) {
-			/* IMM */
-			case 0x00: /* BRK   */                          return 1;
-			case 0xff: /* JCI   */                          if(!s->dat[--s->ptr]) { pc += 2; break; }
-			case 0xfe: /* JMI   */                          pc += PEEK2(ram + pc) + 2; break;
-			case 0xfd: /* JSI   */                SET(0, 2) PUT2(0, pc + 2) pc += PEEK2(ram + pc) + 2; break;
-			case 0xfc: /* LIT   */                SET(0, 1) PUT(0, ram[pc++]) break;
-			case 0xfb: /* LIT2  */                SET(0, 2) PUT2(0, PEEK2(ram + pc)) pc += 2; break;
-			case 0xfa: /* LITr  */                SET(0, 1) PUT(0, ram[pc++]) break;
-			case 0xf9: /* LIT2r */                SET(0, 2) PUT2(0, PEEK2(ram + pc)) pc += 2; break;
-			/* ALU */
-			case 0x01: /* INC  */ t=T;            SET(1, 0) PUT(0, t + 1) break;
-			case 0x21:            t=T2;           SET(2, 0) PUT2(0, t + 1) break;
-			case 0x02: /* POP  */                 SET(1,-1) break;
-			case 0x22:                            SET(2,-2) break;
-			case 0x03: /* NIP  */ t=T;            SET(2,-1) PUT(0, t) break;
-			case 0x23:            t=T2;           SET(4,-2) PUT2(0, t) break;
-			case 0x04: /* SWP  */ t=T;n=N;        SET(2, 0) PUT(0, n) PUT(1, t) break;
-			case 0x24:            t=T2;n=N2;      SET(4, 0) PUT2(0, n) PUT2(2, t) break;
-			case 0x05: /* ROT  */ t=T;n=N;l=L;    SET(3, 0) PUT(0, l) PUT(1, t) PUT(2, n) break;
-			case 0x25:            t=T2;n=N2;l=L2; SET(6, 0) PUT2(0, l) PUT2(2, t) PUT2(4, n) break;
-			case 0x06: /* DUP  */ t=T;            SET(1, 1) PUT(0, t) PUT(1, t) break;
-			case 0x26:            t=T2;           SET(2, 2) PUT2(0, t) PUT2(2, t) break;
-			case 0x07: /* OVR  */ t=T;n=N;        SET(2, 1) PUT(0, n) PUT(1, t) PUT(2, n) break;
-			case 0x27:            t=T2;n=N2;      SET(4, 2) PUT2(0, n) PUT2(2, t) PUT2(4, n) break;
-			case 0x08: /* EQU  */ t=T;n=N;        SET(2,-1) PUT(0, n == t) break;
-			case 0x28:            t=T2;n=N2;      SET(4,-3) PUT(0, n == t) break;
-			case 0x09: /* NEQ  */ t=T;n=N;        SET(2,-1) PUT(0, n != t) break;
-			case 0x29:            t=T2;n=N2;      SET(4,-3) PUT(0, n != t) break;
-			case 0x0a: /* GTH  */ t=T;n=N;        SET(2,-1) PUT(0, n > t) break;
-			case 0x2a:            t=T2;n=N2;      SET(4,-3) PUT(0, n > t) break;
-			case 0x0b: /* LTH  */ t=T;n=N;        SET(2,-1) PUT(0, n < t) break;
-			case 0x2b:            t=T2;n=N2;      SET(4,-3) PUT(0, n < t) break;
-			case 0x0c: /* JMP  */ t=T;            SET(1,-1) pc += (Sint8)t; break;
-			case 0x2c:            t=T2;           SET(2,-2) pc = t; break;
-			case 0x0d: /* JCN  */ t=T;n=N;        SET(2,-2) if(n) pc += (Sint8)t; break;
-			case 0x2d:            t=T2;n=L;       SET(3,-3) if(n) pc = t; break;
-			case 0x0e: /* JSR  */ t=T;            SET(1,-1) FLIP SET(0,2) PUT2(0, pc) pc += (Sint8)t; break;
-			case 0x2e:            t=T2;           SET(2,-2) FLIP SET(0,2) PUT2(0, pc) pc = t; break;
-			case 0x0f: /* STH  */ t=T;            SET(1,-1) FLIP SET(0,1) PUT(0, t) break;
-			case 0x2f:            t=T2;           SET(2,-2) FLIP SET(0,2) PUT2(0, t) break;
-			case 0x10: /* LDZ  */ t=T;            SET(1, 0) PUT(0, ram[t]) break;
-			case 0x30:            t=T;            SET(1, 1) PUT2(0, PEEK2(ram + t)) break;
-			case 0x11: /* STZ  */ t=T;n=N;        SET(2,-2) ram[t] = n; break;
-			case 0x31:            t=T;n=H2;       SET(3,-3) POKE2(ram + t, n) break;
-			case 0x12: /* LDR  */ t=T;            SET(1, 0) PUT(0, ram[pc + (Sint8)t]) break;
-			case 0x32:            t=T;            SET(1, 1) PUT2(0, PEEK2(ram + pc + (Sint8)t)) break;
-			case 0x13: /* STR  */ t=T;n=N;        SET(2,-2) ram[pc + (Sint8)t] = n; break;
-			case 0x33:            t=T;n=H2;       SET(3,-3) POKE2(ram + pc + (Sint8)t, n) break;
-			case 0x14: /* LDA  */ t=T2;           SET(2,-1) PUT(0, ram[t]) break;
-			case 0x34:            t=T2;           SET(2, 0) PUT2(0, PEEK2(ram + t)) break;
-			case 0x15: /* STA  */ t=T2;n=L;       SET(3,-3) ram[t] = n; break;
-			case 0x35:            t=T2;n=N2;      SET(4,-4) POKE2(ram + t, n) break;
-			case 0x16: /* DEI  */ t=T;            SET(1, 0) DEI(0, t) break;
-			case 0x36:            t=T;            SET(1, 1) DEI(1, t) DEI(0, t + 1) break;
-			case 0x17: /* DEO  */ t=T;n=N;        SET(2,-2) DEO(t, n) break;
-			case 0x37:            t=T;n=N;l=L;    SET(3,-3) DEO(t, l) DEO(t + 1, n) break;
-			case 0x18: /* ADD  */ t=T;n=N;        SET(2,-1) PUT(0, n + t) break;
-			case 0x38:            t=T2;n=N2;      SET(4,-2) PUT2(0, n + t) break;
-			case 0x19: /* SUB  */ t=T;n=N;        SET(2,-1) PUT(0, n - t) break;
-			case 0x39:            t=T2;n=N2;      SET(4,-2) PUT2(0, n - t) break;
-			case 0x1a: /* MUL  */ t=T;n=N;        SET(2,-1) PUT(0, n * t) break;
-			case 0x3a:            t=T2;n=N2;      SET(4,-2) PUT2(0, n * t) break;
-			case 0x1b: /* DIV  */ t=T;n=N;        SET(2,-1) if(!t) HALT(3) PUT(0, n / t) break;
-			case 0x3b:            t=T2;n=N2;      SET(4,-2) if(!t) HALT(3) PUT2(0, n / t) break;
-			case 0x1c: /* AND  */ t=T;n=N;        SET(2,-1) PUT(0, n & t) break;
-			case 0x3c:            t=T2;n=N2;      SET(4,-2) PUT2(0, n & t) break;
-			case 0x1d: /* ORA  */ t=T;n=N;        SET(2,-1) PUT(0, n | t) break;
-			case 0x3d:            t=T2;n=N2;      SET(4,-2) PUT2(0, n | t) break;
-			case 0x1e: /* EOR  */ t=T;n=N;        SET(2,-1) PUT(0, n ^ t) break;
-			case 0x3e:            t=T2;n=N2;      SET(4,-2) PUT2(0, n ^ t) break;
-			case 0x1f: /* SFT  */ t=T;n=N;        SET(2,-1) PUT(0, n >> (t & 0xf) << (t >> 4)) break;
-			case 0x3f:            t=T;n=H2;       SET(3,-1) PUT2(0, n >> (t & 0xf) << (t >> 4)) break;
+		if(ins & 0x80) { ksp = s->ptr; sp = &ksp; } else sp = &s->ptr;
+		/* Opcodes */
+		switch(opc - (!opc * (ins >> 5))) {
+		/* Immediate */
+		case -0x0: /* BRK   */ return 1;
+		case -0x1: /* JCI   */ POP1(b) if(!b) { pc += 2; break; } /* else fallthrough */
+		case -0x2: /* JMI   */ pc += PEEK2(ram + pc) + 2; break;
+		case -0x3: /* JSI   */ PUSH2(pc + 2) pc += PEEK2(ram + pc) + 2; break;
+		case -0x4: /* LIT   */
+		case -0x6: /* LITr  */ a = ram[pc++]; PUSH1(a) break;
+		case -0x5: /* LIT2  */
+		case -0x7: /* LIT2r */ PUSH2(PEEK2(ram + pc)) pc += 2; break;
+		/* ALU */
+		case 0x01: /* INC */ POPx(a) PUSHx(a + 1) break;
+		case 0x02: /* POP */ POPx(a) break;
+		case 0x03: /* NIP */ POPx(a) POPx(b) PUSHx(a) break;
+		case 0x04: /* SWP */ POPx(a) POPx(b) PUSHx(a) PUSHx(b) break;
+		case 0x05: /* ROT */ POPx(a) POPx(b) POPx(c) PUSHx(b) PUSHx(a) PUSHx(c) break;
+		case 0x06: /* DUP */ POPx(a) PUSHx(a) PUSHx(a) break;
+		case 0x07: /* OVR */ POPx(a) POPx(b) PUSHx(b) PUSHx(a) PUSHx(b) break;
+		case 0x08: /* EQU */ POPx(a) POPx(b) PUSH1(b == a) break;
+		case 0x09: /* NEQ */ POPx(a) POPx(b) PUSH1(b != a) break;
+		case 0x0a: /* GTH */ POPx(a) POPx(b) PUSH1(b > a) break;
+		case 0x0b: /* LTH */ POPx(a) POPx(b) PUSH1(b < a) break;
+		case 0x0c: /* JMP */ POPx(a) JUMP(a) break;
+		case 0x0d: /* JCN */ POPx(a) POP1(b) if(b) JUMP(a) break;
+		case 0x0e: /* JSR */ POPx(a) FLIP PUSH2(pc) JUMP(a) break;
+		case 0x0f: /* STH */ POPx(a) FLIP PUSHx(a) break;
+		case 0x10: /* LDZ */ POP1(a) PEEK(b, a) PUSHx(b) break;
+		case 0x11: /* STZ */ POP1(a) POPx(b) POKE(a, b) break;
+		case 0x12: /* LDR */ POP1(a) PEEK(b, pc + (Sint8)a) PUSHx(b) break;
+		case 0x13: /* STR */ POP1(a) POPx(b) POKE(pc + (Sint8)a, b) break;
+		case 0x14: /* LDA */ POP2(a) PEEK(b, a) PUSHx(b) break;
+		case 0x15: /* STA */ POP2(a) POPx(b) POKE(a, b) break;
+		case 0x16: /* DEI */ POP1(a) DEVR(b, a) PUSHx(b) break;
+		case 0x17: /* DEO */ POP1(a) POPx(b) DEVW(a, b) break;
+		case 0x18: /* ADD */ POPx(a) POPx(b) PUSHx(b + a) break;
+		case 0x19: /* SUB */ POPx(a) POPx(b) PUSHx(b - a) break;
+		case 0x1a: /* MUL */ POPx(a) POPx(b) PUSHx((Uint32)b * a) break;
+		case 0x1b: /* DIV */ POPx(a) POPx(b) if(!a) HALT(3) PUSHx(b / a) break;
+		case 0x1c: /* AND */ POPx(a) POPx(b) PUSHx(b & a) break;
+		case 0x1d: /* ORA */ POPx(a) POPx(b) PUSHx(b | a) break;
+		case 0x1e: /* EOR */ POPx(a) POPx(b) PUSHx(b ^ a) break;
+		case 0x1f: /* SFT */ POP1(a) POPx(b) PUSHx(b >> (a & 0xf) << (a >> 4)) break;
 		}
 	}
 }
diff --git a/src/uxn.h b/src/uxn.h
index 223d22c..367b920 100644
--- a/src/uxn.h
+++ b/src/uxn.h
@@ -15,6 +15,8 @@ WITH REGARD TO THIS SOFTWARE.
 
 #define POKE2(d, v) { (d)[0] = (v) >> 8; (d)[1] = (v); }
 #define PEEK2(d) ((d)[0] << 8 | (d)[1])
+#define DEO(p, value) { u->dev[p] = value; if((deo_mask[p >> 4] >> (p & 0xf)) & 0x1) emu_deo(u, p); }
+#define DEI(p) ((dei_mask[(p) >> 4] >> ((p) & 0xf)) & 0x1 ? emu_dei(u, (p)) : u->dev[(p)])
 
 /* clang-format on */