Allowed more kinds of constants within variable and array initializers

CHANGELOG.md

@@ -6,6 +6,8 @@
 
 * `-fzp-register` is now enabled by default, as the documentation has already been saying.
 
+* Allowed more kinds of constants within variable and array initializers.
+
 * Fixed several bugs.
 
 * Other improvements.

src/main/scala/millfork/compiler/ReturnDispatch.scala

@@ -53,25 +53,23 @@ object ReturnDispatch {
     }
 
     val returnType = ctx.function.returnType
-    val map = mutable.Map[Int, (Constant, List[Constant])]()
+    val map: mutable.Map[Int, (String, List[Expression])] = mutable.Map()
     var min = Option.empty[Int]
     var max = Option.empty[Int]
-    var default = Option.empty[(Constant, List[Constant])]
+    var default = Option.empty[(String, List[Expression])]
     stmt.branches.foreach { branch =>
-      val function = ctx.env.evalForAsm(branch.function).getOrElse {
-        ErrorReporting.error("Undefined function or Non-constant function address for dispatch branch", branch.function.position)
-        Constant.Zero
+      val function: String = ctx.env.evalForAsm(branch.function) match {
+        case Some(MemoryAddressConstant(f: FunctionInMemory)) =>
+          if (f.returnType.name != returnType.name) {
+            ErrorReporting.warn(s"Dispatching to a function of different return type: dispatcher return type: ${returnType.name}, dispatchee return type: ${f.returnType.name}", ctx.options, branch.function.position)
+          }
+          f.name
+        case _ =>
+          ErrorReporting.error("Undefined function or Non-constant function address for dispatch branch", branch.function.position)
+          ""
       }
-      if (returnType.name != "void") {
-        function match {
-          case MemoryAddressConstant(f: FunctionInMemory) =>
-            if (f.returnType.name != returnType.name) {
-              ErrorReporting.warn(s"Dispatching to a function of different return type: dispatcher return type: ${returnType.name}, dispatchee return type: ${f.returnType.name}", ctx.options, branch.function.position)
-            }
-          case _ => ()
-        }
-      }
-      val params = branch.params.map(toConstant)
+      branch.params.foreach(toConstant)
+      val params = branch.params
       if (params.length > stmt.params.length) {
         ErrorReporting.error("Too many parameters for dispatch branch", branch.params.head.position)
       }
@@ -102,7 +100,7 @@ object ReturnDispatch {
     }
     val actualMin = defaultMin min nonDefaultMin.getOrElse(defaultMin)
     val actualMax = defaultMax max nonDefaultMax.getOrElse(defaultMax)
-    val zeroes = Constant.Zero -> List[Constant]()
+    val zeroes = "" -> List[Expression]()
     for (i <- actualMin to actualMax) {
       if (!map.contains(i)) map(i) = default.getOrElse {
         // TODO: warning?
@@ -125,7 +123,7 @@ object ReturnDispatch {
     val label = MfCompiler.nextLabel("di")
     val paramArrays = stmt.params.indices.map { ix =>
       val a = InitializedArray(label + "$" + ix + ".array", None, (paramMins(ix) to paramMaxes(ix)).map { key =>
-        map(key)._2.lift(ix).getOrElse(Constant.Zero)
+        map(key)._2.lift(ix).getOrElse(LiteralExpression(0, 1))
       }.toList,
         ctx.function.declaredBank)
       env.registerUnnamedArray(a)
@@ -147,7 +145,7 @@ object ReturnDispatch {
     }
 
     if (useJmpaix) {
-      val jumpTable = InitializedArray(label + "$jt.array", None, (actualMin to actualMax).flatMap(i => List(map(i)._1.loByte, map(i)._1.hiByte)).toList, ctx.function.declaredBank)
+      val jumpTable = InitializedArray(label + "$jt.array", None, (actualMin to actualMax).flatMap(i => List(lobyte0(map(i)._1), hibyte0(map(i)._1))).toList, ctx.function.declaredBank)
       env.registerUnnamedArray(jumpTable)
       if (copyParams.isEmpty) {
         val loadIndex = ExpressionCompiler.compile(ctx, stmt.indexer, Some(b -> RegisterVariable(Register.A, b)), BranchSpec.None)
@@ -162,8 +160,8 @@ object ReturnDispatch {
       }
     } else {
       val loadIndex = ExpressionCompiler.compile(ctx, stmt.indexer, Some(b -> RegisterVariable(Register.X, b)), BranchSpec.None)
-      val jumpTableLo = InitializedArray(label + "$jl.array", None, (actualMin to actualMax).map(i => (map(i)._1 - 1).loByte).toList, ctx.function.declaredBank)
-      val jumpTableHi = InitializedArray(label + "$jh.array", None, (actualMin to actualMax).map(i => (map(i)._1 - 1).hiByte).toList, ctx.function.declaredBank)
+      val jumpTableLo = InitializedArray(label + "$jl.array", None, (actualMin to actualMax).map(i => lobyte1(map(i)._1)).toList, ctx.function.declaredBank)
+      val jumpTableHi = InitializedArray(label + "$jh.array", None, (actualMin to actualMax).map(i => hibyte1(map(i)._1)).toList, ctx.function.declaredBank)
       env.registerUnnamedArray(jumpTableLo)
       env.registerUnnamedArray(jumpTableHi)
       loadIndex ++ copyParams ++ List(
@@ -174,4 +172,20 @@ object ReturnDispatch {
         AssemblyLine.implied(RTS))
     }
   }
+
+  private def lobyte0(fname: String): Expression = if (fname == "") LiteralExpression(0, 1) else {
+    FunctionCallExpression("lo",List(VariableExpression(fname + ".addr")))
+  }
+
+  private def hibyte0(fname: String): Expression = if (fname == "") LiteralExpression(0, 1) else {
+    FunctionCallExpression("hi",List(VariableExpression(fname + ".addr")))
+  }
+
+  private def lobyte1(fname: String): Expression = if (fname == "") LiteralExpression(0, 1) else {
+    FunctionCallExpression("lo", List(SumExpression(List(false -> VariableExpression(fname + ".addr"), true -> LiteralExpression(1, 1)), decimal = false)))
+  }
+
+  private def hibyte1(fname: String): Expression = if (fname == "") LiteralExpression(0, 1) else {
+    FunctionCallExpression("hi", List(SumExpression(List(false -> VariableExpression(fname + ".addr"), true -> LiteralExpression(1, 1)), decimal = false)))
+  }
 }

src/main/scala/millfork/env/Environment.scala

@@ -348,6 +348,20 @@ class Environment(val parent: Option[Environment], val prefix: String) {
       } yield hc.asl(8) + lc
       case FunctionCallExpression(name, params) =>
         name match {
+          case "hi" =>
+            if (params.size == 1) {
+              eval(params.head).map(_.hiByte.quickSimplify)
+            } else {
+              ErrorReporting.error("Invalid number of parameters for `hi`", e.position)
+              None
+            }
+          case "lo" =>
+            if (params.size == 1) {
+              eval(params.head).map(_.loByte.quickSimplify)
+            } else {
+              ErrorReporting.error("Invalid number of parameters for `lo`", e.position)
+              None
+            }
           case "nonet" =>
             params match {
               case List(FunctionCallExpression("<<", ps@List(_, _))) =>
@@ -358,7 +372,10 @@ class Environment(val parent: Option[Environment], val prefix: String) {
                 constantOperation(MathOperator.Plus9, ps.map(_._2))
               case List(SumExpression(ps@List((true,_),(true,_)), true)) =>
                 constantOperation(MathOperator.DecimalPlus9, ps.map(_._2))
+              case List(_) =>
+                None
               case _ =>
+                ErrorReporting.error("Invalid number of parameters for `nonet`", e.position)
                 None
             }
           case ">>'" =>
@@ -660,9 +677,7 @@ class Environment(val parent: Option[Environment], val prefix: String) {
         val length = contents.length
         if (length > 0xffff || length < 0) ErrorReporting.error(s"Array `${stmt.name}` has invalid length", stmt.position)
         val address = stmt.address.map(a => eval(a).getOrElse(Constant.error(s"Array `${stmt.name}` has non-constant address", stmt.position)))
-        val data = contents.map(x => eval(x).getOrElse(Constant.error(s"Array `${stmt.name}` has non-constant contents", stmt.position)))
-        val array = InitializedArray(stmt.name + ".array", address, data,
-                    declaredBank = stmt.bank)
+        val array = InitializedArray(stmt.name + ".array", address, contents, declaredBank = stmt.bank)
         addThing(array, stmt.position)
         registerAddressConstant(UninitializedMemoryVariable(stmt.name, p, VariableAllocationMethod.None,
                     declaredBank = stmt.bank), stmt.position)
@@ -748,9 +763,7 @@ class Environment(val parent: Option[Environment], val prefix: String) {
             if (options.flags(CompilationFlag.ReadOnlyArrays)) {
               ErrorReporting.warn("Initialized variable in read-only segment", options, position)
             }
-            val ivc = eval(ive).getOrElse(Constant.error(s"Initial value of `$name` is not a constant", position))
-            InitializedMemoryVariable(name, None, typ, ivc,
-                        declaredBank = stmt.bank)
+            InitializedMemoryVariable(name, None, typ, ive, declaredBank = stmt.bank)
           }
           registerAddressConstant(v, stmt.position)
           (v, v.toAddress)
@@ -815,8 +828,7 @@ class Environment(val parent: Option[Environment], val prefix: String) {
 
   def collectDeclarations(program: Program, options: CompilationOptions): Unit = {
     if (options.flag(CompilationFlag.OptimizeForSonicSpeed)) {
-      addThing(InitializedArray("identity$", None, List.tabulate(256)(n => NumericConstant(n, 1)),
-                  declaredBank = None), None)
+      addThing(InitializedArray("identity$", None, List.tabulate(256)(n => LiteralExpression(n, 1)), declaredBank = None), None)
     }
     program.declarations.foreach {
       case f: FunctionDeclarationStatement => registerFunction(f, options)
@@ -838,8 +850,7 @@ class Environment(val parent: Option[Environment], val prefix: String) {
         address = None), options)
     }
     if (!things.contains("__constant8")) {
-      things("__constant8") = InitializedArray("__constant8", None, List(NumericConstant(8, 1)),
-                  declaredBank = None)
+      things("__constant8") = InitializedArray("__constant8", None, List(LiteralExpression(8, 1)), declaredBank = None)
     }
   }
 

src/main/scala/millfork/env/Thing.scala

@@ -155,7 +155,7 @@ case class UninitializedMemoryVariable(name: String, typ: Type, alloc: VariableA
   override def toAddress: MemoryAddressConstant = MemoryAddressConstant(this)
 }
 
-case class InitializedMemoryVariable(name: String, address: Option[Constant], typ: Type, initialValue: Constant, declaredBank: Option[String]) extends MemoryVariable with PreallocableThing {
+case class InitializedMemoryVariable(name: String, address: Option[Constant], typ: Type, initialValue: Expression, declaredBank: Option[String]) extends MemoryVariable with PreallocableThing {
   override def zeropage: Boolean = false
 
   override def toAddress: MemoryAddressConstant = MemoryAddressConstant(this)
@@ -185,7 +185,7 @@ case class RelativeArray(name: String, address: Constant, sizeInBytes: Int, decl
   override def bank(compilationOptions: CompilationOptions): String = declaredBank.getOrElse("default")
 }
 
-case class InitializedArray(name: String, address: Option[Constant], contents: List[Constant], declaredBank: Option[String]) extends MfArray with PreallocableThing {
+case class InitializedArray(name: String, address: Option[Constant], contents: List[Expression], declaredBank: Option[String]) extends MfArray with PreallocableThing {
   override def shouldGenerate = true
 
   override def isFar(compilationOptions: CompilationOptions): Boolean = farFlag.getOrElse(false)

src/main/scala/millfork/node/Node.scala

@@ -1,7 +1,7 @@
 package millfork.node
 
 import millfork.assembly.{AddrMode, Opcode}
-import millfork.env.{Label, ParamPassingConvention}
+import millfork.env.{Constant, Label, ParamPassingConvention}
 
 case class Position(filename: String, line: Int, column: Int, cursor: Int)
 

src/main/scala/millfork/output/Assembler.scala

@@ -215,7 +215,10 @@ class Assembler(private val program: Program, private val rootEnv: Environment,
         assembly.append("* = $" + index.toHexString)
         assembly.append(name)
         for (item <- items) {
-          writeByte(bank, index, item)
+          env.eval(item) match {
+            case Some(c) => writeByte(bank, index, c)
+            case None => ErrorReporting.error(s"Non-constant contents of array `$name`")
+          }
           bank0.occupied(index) = true
           bank0.initialized(index) = true
           bank0.writeable(index) = true
@@ -281,7 +284,10 @@ class Assembler(private val program: Program, private val rootEnv: Environment,
         assembly.append("* = $" + index.toHexString)
         assembly.append(name)
         for (item <- items) {
-          writeByte(bank, index, item)
+          env.eval(item) match {
+            case Some(c) => writeByte(bank, index, c)
+            case None => ErrorReporting.error(s"Non-constant contents of array `$name`")
+          }
           index += 1
         }
         items.grouped(16).foreach {group =>
@@ -298,10 +304,16 @@ class Assembler(private val program: Program, private val rootEnv: Environment,
         env.things += altName -> ConstantThing(altName, NumericConstant(index, 2), env.get[Type]("pointer"))
         assembly.append("* = $" + index.toHexString)
         assembly.append(name)
-        for (i <- 0 until typ.size) {
-          writeByte(bank, index, value.subbyte(i))
-          assembly.append("    !byte " + value.subbyte(i).quickSimplify)
-          index += 1
+        env.eval(value) match {
+          case Some(c) =>
+            for (i <- 0 until typ.size) {
+              writeByte(bank, index, c.subbyte(i))
+              assembly.append("    !byte " + c.subbyte(i).quickSimplify)
+              index += 1
+            }
+          case None =>
+            ErrorReporting.error(s"Non-constant initial value for variable `$name`")
+            index += typ.size
         }
         initializedVariablesSize += typ.size
         justAfterCode += bank -> index