how about some rng?

Videotron2K.md

@@ -97,16 +97,17 @@ Commands can have "conditional postfix" used to execute the command conditionall
 
 NOTE : immediates and variables can substitute registers
 
-* add rA rB rC : rC = rA + rB
+* add rA rB rC : rA = rB + rC
-* sub rA rB rC : rC = rA - rB
+* sub rA rB rC : rA = rB - rC
-* mul rA rB rC : rC = rA * rB
+* mul rA rB rC : rA = rB * rC
-* div rA rB rC : rC = rA / rB
+* div rA rB rC : rA = rB / rC
-* and rA rB rC : rC = rA & rB
+* mod rA rB rC : rA = rB % rC
-* or rA rB rC : rC = rA | rB
+* and rA rB rC : rA = rB & rC
-* xor rA rB rC : rC = rA ^ rB
+* or rA rB rC : rA = rB | rC
-* shl rA rB rC : rC = rA << rB
+* xor rA rB rC : rA = rB ^ rC
-* shr rA rB rC : rC = rA >> rB
+* shl rA rB rC : rA = rB << rC
-* ushr rA rB rC : rC = rA >>> rB
+* shr rA rB rC : rA = rB >> rC
+* ushr rA rB rC : rA = rB >>> rC
 
 * inc R : R = R + 1
 * dec R : R = R - 1
@@ -117,7 +118,7 @@ NOTE : immediates and variables can substitute registers
 
 NOTE : immediates and variables can substitute registers
 
-* cmp rA rB rC : compares rA and rB and stores result to rC. 1 if rA > rB, -1 if rA < rB, 0 if rA == rB.
+* cmp rA rB rC : compares rB and rC and stores result to rA. 1 if rB > rC, -1 if rB < rC, 0 if rB == rC.
 
 ### Data Control
 

src/net/torvald/tsvm/vdc/Videotron2K.kt

@@ -76,12 +76,22 @@ class Videotron2K(var gpu: GraphicsAdapter?) {
         DEFINE height 448
         DEFINE width 560
 
+        mov r6 12345
+
+        SCENE rng ; r6 is RNG value
+            mul r6 r6 48271
+            mod r6 r6 2147483647
+            exit
+        END SCENE
+
         SCENE fill_line
           @ mov px 0
-            plot c1 ; will auto-increment px by one
+            perform rng
-            inc c1
+            plot r6
-            cmp c1 251 r1
+            ; plot c1 ; will auto-increment px by one
-            movzr r1 c1 0     ; mov (-zr r1) c1 0 -- first, the comparison is made with r1 then runs 'mov c1 0' if r1 == 0
+            ; inc c1
+            ; cmp r1 c1 251
+            ; movzr r1 c1 0     ; mov (-zr r1) c1 0 -- first, the comparison is made with r1 then runs 'mov c1 0' if r1 == 0
             exitzr px
         END SCENE
         
@@ -89,7 +99,7 @@ class Videotron2K(var gpu: GraphicsAdapter?) {
           @ mov py 0
             perform fill_line
             inc py
-            cmp py 448 r1
+            cmp r1 py 448
             movzr r1 py 0
             next
             ; exeunt
@@ -371,6 +381,7 @@ object Command {
     const val DEC = 0x60
     const val NOT = 0x68
     const val NEG = 0x70
+    const val MOD = 0x78
 
     const val CMP = 0x80
     const val MOV = 0x88
@@ -418,6 +429,7 @@ object Command {
             "DEC" to DEC,
             "NOT" to NOT,
             "NEG" to NEG,
+            "MOD" to MOD,
 
             "CMP" to CMP,
 
@@ -496,6 +508,15 @@ object Command {
             checkRegisterLH(args[0])
             instance.regs.setInt((args[0] and 0xF) * 4, resolveVar(instance, args[1]))
         }
+        instSet[MUL shr 3] = { instance, args -> // MUL ACC LH RH
+            twoArgArithmetic(instance, args) { a,b -> a*b }
+        }
+        instSet[ADD shr 3] = { instance, args -> // ADD ACC LH RH
+            twoArgArithmetic(instance, args) { a,b -> a+b }
+        }
+        instSet[MOD shr 3] = { instance, args -> // MOD ACC LH RH
+            twoArgArithmetic(instance, args) { a,b -> a fmod b }
+        }
         instSet[INC shr 3] = { instance, args -> // INC register
             if (args.size != 1) throw ArgsCountMismatch(1, args)
             checkRegisterLH(args[0])
@@ -515,11 +536,7 @@ object Command {
             instance.performanceCounterTmr = System.nanoTime()
         }
         instSet[CMP shr 3] = { instance, args -> // CMP rA rB rC
-            if (args.size != 3) throw ArgsCountMismatch(3, args)
+            twoArgArithmetic(instance, args) { a,b -> if (a>b) 1 else if (a<b) -1 else 0 }
-            val v1 = resolveVar(instance, args[0])
-            val v2 = resolveVar(instance, args[1])
-            val cmpvar = if (v1 > v2) 1 else if (v1 < v2) -1 else 0
-            instance.regs.setInt((args[2] and 0xF) * 4, cmpvar)
         }
         instSet[PLOT shr 3] = { instance, args -> // PLOT vararg-bytes
             if (args.isNotEmpty()) {
@@ -554,6 +571,14 @@ object Command {
         }
     }
 
+    private inline fun twoArgArithmetic(instance: Videotron2K, args: LongArray, operation: (Int, Int) -> Int) {
+        if (args.size != 3) throw ArgsCountMismatch(3, args)
+        checkRegisterLH(args[0])
+        val lh = resolveVar(instance, args[1])
+        val rh = resolveVar(instance, args[2])
+        instance.regs.setInt((args[0] and 0xF) * 4, operation(lh, rh))
+    }
+
     fun checkConditionAndRun(inst: Int, instance: Videotron2K, args: LongArray) {
         val opcode = inst shr 3
         val condCode = inst and 7