For-to loop fixes

doc/abi/generated-labels.md

@@ -44,6 +44,8 @@ where `11111` is a sequential number and `xx` is the type:
 
 * `th` – beginning of the "then" block in an `if` statement
 
+* `to` – end of a `for-to` loop
+
 * `wh` – beginning of a `while` statement
 
 

src/main/scala/millfork/compiler/MfCompiler.scala

@@ -1745,12 +1745,24 @@ object MfCompiler {
                 FunctionCallExpression("<", List(vex, f.end)),
                 f.body :+ increment),
             ))
+//          case (ForDirection.To | ForDirection.ParallelTo, _, Some(NumericConstant(n, _))) if n > 0 && n < 255 =>
+//            compile(ctx, List(
+//              Assignment(vex, f.start),
+//              WhileStatement(
+//                FunctionCallExpression("<=", List(vex, f.end)),
+//                f.body :+ increment),
+//            ))
           case (ForDirection.To | ForDirection.ParallelTo, _, _) =>
+            val label = nextLabel("to")
             compile(ctx, List(
               Assignment(vex, f.start),
               WhileStatement(
-                FunctionCallExpression("<=", List(vex, f.end)),
-                f.body :+ increment),
+                VariableExpression("true"),
+                f.body :+ IfStatement(
+                  FunctionCallExpression("==", List(vex, f.end)),
+                  List(AssemblyStatement(JMP, AddrMode.Absolute, VariableExpression(label), elidable = true)),
+                  List(increment))),
+              AssemblyStatement(LABEL, AddrMode.DoesNotExist, VariableExpression(label), elidable=true)
             ))
           case (ForDirection.DownTo, _, _) =>
             compile(ctx, List(

src/test/scala/millfork/test/ForLoopSuite.scala

@@ -1,6 +1,6 @@
 package millfork.test
 
-import millfork.test.emu.EmuBenchmarkRun
+import millfork.test.emu.{EmuBenchmarkRun, EmuUnoptimizedRun}
 import org.scalatest.{FunSuite, Matchers}
 
 /**
@@ -21,6 +21,26 @@ class ForLoopSuite extends FunSuite with Matchers {
         | }
       """.stripMargin)(_.readByte(0xc000) should equal(15))
   }
+
+  test("For-to 2") {
+    EmuBenchmarkRun(
+      """
+        | word output @$c000
+        | byte five
+        | void main () {
+        |   init()
+        |   byte i
+        |   output = 0
+        |   for i,0,to,five {
+        |     output += i
+        |   }
+        | }
+        | void init() {
+        |   five = 5
+        | }
+      """.stripMargin)(_.readByte(0xc000) should equal(15))
+  }
+
   test("For-downto") {
     EmuBenchmarkRun(
       """
@@ -73,4 +93,41 @@ class ForLoopSuite extends FunSuite with Matchers {
         | }
       """.stripMargin)(_.readByte(0xc000) should equal(15))
   }
+
+  test("Various loops") {
+    EmuUnoptimizedRun(
+      """
+        | void init() {
+        |     zero = 0
+        |     ff = $ff
+        | }
+        | byte zero
+        | byte ff
+        | byte flag @$c000
+        | void main () {
+        |     init()
+        |     byte i
+        |     flag = 0
+        |     for i, zero, until, ff { }
+        |     flag = 1
+        |     for i, zero, to, ff { }
+        |     flag = 2
+        |     for i, ff, downto, zero { }
+        |     flag = 3
+        |     for i, zero, paralleluntil, ff { }
+        |     flag = 4
+        |     for i, zero, parallelto, ff { }
+        |     flag = 5
+        |     for i, ff, until, zero { _panic() }
+        |     flag = 6
+        |     for i, ff, paralleluntil, zero { _panic() }
+        |     flag = 7
+        |     for i, ff, paralleluntil, zero { _panic() }
+        |     flag = 8
+        |     for i, zero, until, ff { }
+        |     flag = 9
+        | }
+        | void _panic(){while(true){}}
+      """.stripMargin)
+  }
 }

src/test/scala/millfork/test/emu/EmuRun.scala

@@ -222,6 +222,7 @@ class EmuRun(cpu: millfork.Cpu.Value, nodeOptimizations: List[NodeOptimization],
         }
       }
     }
+    ErrorReporting.trace(f"[$$c000] = ${memoryBank.readByte(0xc000)}%02X")
     countCmos should be < TooManyCycles
     println(countNmos + " NMOS cycles")
     println(countCmos + " CMOS cycles")