simplistic repeat and while loops

compiler/src/prog8/compiler/target/c64/codegen2/AsmGen2.kt

@@ -836,14 +836,44 @@ internal class AsmGen2(val program: Program,
     }
 
     private fun translate(stmt: WhileLoop) {
-        TODO("while $stmt")
+        val whileLabel = makeLabel("while")
+        val endLabel = makeLabel("whileend")
+        out(whileLabel)
+        // TODO optimize for the simple cases, can we avoid stack use?
+        translateExpression(stmt.condition)
+        if(stmt.condition.inferType(program) in ByteDatatypes) {
+            out("  inx |  lda  $ESTACK_LO_HEX,x  |  beq  $endLabel")
+        } else {
+            out("""
+                inx
+                lda  $ESTACK_LO_HEX,x
+                bne  +
+                lda  $ESTACK_HI_HEX,x
+                beq  $endLabel
++  """)
+        }
+        translate(stmt.body)
+        out("  jmp  $whileLabel")
+        out(endLabel)
     }
 
     private fun translate(stmt: RepeatLoop) {
-        // TODO("repeat $stmt")
-        out(";------ TODO REPEAT")
+        val repeatLabel = makeLabel("repeat")
+        out(repeatLabel)
+        // TODO optimize this for the simple cases, can we avoid stack use?
         translate(stmt.body)
-        out(";------ TODO REPEAT  END")
+        translateExpression(stmt.untilCondition)
+        if(stmt.untilCondition.inferType(program) in ByteDatatypes) {
+            out("  inx |  lda  $ESTACK_LO_HEX,x  |  beq  $repeatLabel")
+        } else {
+            out("""
+                inx
+                lda  $ESTACK_LO_HEX,x
+                bne  +
+                lda  $ESTACK_HI_HEX,x
+                beq  $repeatLabel
++ """)
+        }
     }
 
     private fun translate(stmt: WhenStatement) {

examples/test.p8

@@ -4,32 +4,22 @@ main {
 
     sub start() {
 
-        byte b1
-        byte b2
-        word w1
-        word w2
-        ubyte ub1
-        ubyte ub2
-        uword uw1
-        uword uw2
+        byte bb=10
 
-        b1 = 5
-        b2= 122
-        b1 = b2+b1
-        c64scr.print_b(b1)
-        c64.CHROUT('\n')
+        while bb<15 {
+            bb++
+            c64scr.print_b(bb)
+            c64.CHROUT('\n')
+        }
+
+        word ww=5
+
+        while ww > -5 {
+            ww--
+            c64scr.print_w(ww)
+            c64.CHROUT('\n')
+        }
 
-        w1 = -1111
-        w2 = 11231
-        w1 = w2+w1
-        c64scr.print_w(w1)
-        c64.CHROUT('\n')
 
-        uw1 = 55555
-        uw2 = 1123
-        uw1 = uw2+uw1
-        c64scr.print_uw(uw1)
-        c64.CHROUT('\n')
-        c64.CHROUT('\n')
     }
 }