inc/dec support for self-modifying code

6502.js

@@ -149,11 +149,11 @@ function clv(m) { return "v=0;"; }
 function cmp(m) { ssz("w"); return "c=(a>="+m+");w=(a-"+m+")&255;"; }
 function cpx(m) { ssz("w"); return "c=(x>="+m+");w=(x-"+m+")&255;"; }
 function cpy(m) { ssz("w"); return "c=(y>="+m+");w=(y-"+m+")&255;"; }
-function dec(m) { ssz(m); return m+"=("+m+"-1)&255;"; }
+function dec(m) { ssz(m); return "maykill("+m.substr(2,m.length-3)+");"+m+"=("+m+"-1)&255;if(!alive){ip="+ip+";return;}"; }
 function dex(m) { ssz("x"); return "x=(x-1)&255;"; }
 function dey(m) { ssz("y"); return "y=(y-1)&255;"; }
 function eor(m) { ssz("a"); return "a^="+m+";"; }
-function inc(m) { ssz(m); return m+"=("+m+"+1)&255;"; }
+function inc(m) { ssz(m); return "maykill("+m.substr(2,m.length-3)+");"+m+"=("+m+"+1)&255;if(!alive){ip="+ip+";return;}"; }
 function inx(m) { ssz("x"); return "x=(x+1)&255;"; }
 function iny(m) { ssz("y"); return "y=(y+1)&255;"; }
 function jmp(m) { return fsz()+"ip="+m+"; return;"; }
@@ -271,7 +271,7 @@ function jit()
 {
     var count = 0, code = "(function(){";
     var ip0 = ip, addr;
-    var NN = 100;
+    var NN = 2;
     while (count < NN)
     {
         count += 1;

demo2.asm

@@ -25,16 +25,20 @@ start:
     ; "Regular" non-self-modifying code
     ;
     ldx #$00
-    ldy #$00
+    ldy #$10
     lda #$00
+    sta set_row
+    sta set_col
 loop1:
-    stx write_pixel
-    inx
+    sta write_pixel
+    clc
+    adc #$01
     bne loop1
-    iny
+    dex
     bne loop1
     clc
     adc #$01
+    dey
     bne loop1
     jmp $0300
 
@@ -43,14 +47,15 @@ loop1:
     ; Self-modifying code
     ;
     ldx #$00
-    ldy #$00
+    ldy #$10
 loop2:
     lda #$00 ; <----- $00 will be incremented!
     sta write_pixel
     inc $0305
     bne loop2
     dex
     bne loop2
+    inc $0305
     dey
     bne loop2
     jmp $0000