Refactoring for the upcoming Z80 support

src/main/scala/millfork/CompilationOptions.scala

@@ -68,6 +68,17 @@ case class CompilationOptions(platform: Platform, commandLineFlags: Map[Compilat
   }
 }
 
+object CpuFamily extends Enumeration {
+  val M6502, Z80, M6809, I8086, M65K, ARM = Value
+
+  def forType(cpu: Cpu.Value): CpuFamily.Value = {
+    import Cpu._
+    cpu match {
+      case Mos | StrictMos | Ricoh | StrictRicoh | Cmos | HuC6280 | CE02 | Sixteen => M6502
+    }
+  }
+}
+
 object Cpu extends Enumeration {
 
   val Mos, StrictMos, Ricoh, StrictRicoh, Cmos, HuC6280, CE02, Sixteen = Value
@@ -76,27 +87,27 @@ object Cpu extends Enumeration {
 
   import CompilationFlag._
 
-  private val alwaysDefaultFlags = Set(
+  private val mosAlwaysDefaultFlags = Set(
     VariableOverlap, CompactReturnDispatchParams, ZeropagePseudoregister
   )
 
   def defaultFlags(x: Cpu.Value): Set[CompilationFlag.Value] = x match {
     case StrictMos =>
-      alwaysDefaultFlags ++ Set(DecimalMode, PreventJmpIndirectBug)
+      mosAlwaysDefaultFlags ++ Set(DecimalMode, PreventJmpIndirectBug)
     case Mos =>
-      alwaysDefaultFlags ++ Set(DecimalMode, PreventJmpIndirectBug)
+      mosAlwaysDefaultFlags ++ Set(DecimalMode, PreventJmpIndirectBug)
     case Ricoh =>
-      alwaysDefaultFlags ++ Set(PreventJmpIndirectBug)
+      mosAlwaysDefaultFlags ++ Set(PreventJmpIndirectBug)
     case StrictRicoh =>
-      alwaysDefaultFlags ++ Set(PreventJmpIndirectBug)
+      mosAlwaysDefaultFlags ++ Set(PreventJmpIndirectBug)
     case Cmos =>
-      alwaysDefaultFlags ++ Set(DecimalMode, EmitCmosOpcodes)
+      mosAlwaysDefaultFlags ++ Set(DecimalMode, EmitCmosOpcodes)
     case HuC6280 =>
-      alwaysDefaultFlags ++ Set(DecimalMode, EmitCmosOpcodes, EmitHudsonOpcodes)
+      mosAlwaysDefaultFlags ++ Set(DecimalMode, EmitCmosOpcodes, EmitHudsonOpcodes)
     case CE02 =>
-      alwaysDefaultFlags ++ Set(DecimalMode, EmitCmosOpcodes, Emit65CE02Opcodes)
+      mosAlwaysDefaultFlags ++ Set(DecimalMode, EmitCmosOpcodes, Emit65CE02Opcodes)
     case Sixteen =>
-      alwaysDefaultFlags ++ Set(DecimalMode, EmitCmosOpcodes, EmitEmulation65816Opcodes, EmitNative65816Opcodes, ReturnWordsViaAccumulator)
+      mosAlwaysDefaultFlags ++ Set(DecimalMode, EmitCmosOpcodes, EmitEmulation65816Opcodes, EmitNative65816Opcodes, ReturnWordsViaAccumulator)
   }
 
   def fromString(name: String): Cpu.Value = name match {

src/main/scala/millfork/Main.scala

@@ -4,14 +4,16 @@ import java.nio.charset.StandardCharsets
 import java.nio.file.{Files, Paths}
 import java.util.Locale
 
-import millfork.assembly.opt._
+import millfork.assembly.mos.AssemblyLine
+import millfork.assembly.mos.opt._
 import millfork.buildinfo.BuildInfo
 import millfork.cli.{CliParser, CliStatus}
+import millfork.compiler.mos.MosCompiler
 import millfork.env.Environment
 import millfork.error.ErrorReporting
 import millfork.node.StandardCallGraph
-import millfork.output.Assembler
-import millfork.parser.SourceLoadingQueue
+import millfork.output.{AbstractAssembler, AssemblerOutput, MosAssembler, MosInliningCalculator}
+import millfork.parser.MosSourceLoadingQueue
 
 /**
   * @author Karol Stasiak
@@ -59,7 +61,6 @@ object Main {
       ErrorReporting.fatalQuit("No input files")
     }
     ErrorReporting.verbosity = c.verbosity.getOrElse(0)
-    val optLevel = c.optimizationLevel.getOrElse(0)
     val platform = Platform.lookupPlatformFile(c.includePath, c.platform.getOrElse {
       ErrorReporting.info("No platform selected, defaulting to `c64`")
       "c64"
@@ -84,52 +85,9 @@ object Main {
 //      }
 //    }).toMap
 
-    val unoptimized = new SourceLoadingQueue(
-      initialFilenames = c.inputFileNames,
-      includePath = c.includePath,
-      options = options).run()
-
-    val program = if (optLevel > 0) {
-      OptimizationPresets.NodeOpt.foldLeft(unoptimized)((p, opt) => p.applyNodeOptimization(opt, options))
-    } else {
-      unoptimized
+    val result: AssemblerOutput = CpuFamily.forType(platform.cpu) match {
+      case CpuFamily.M6502 => assembleForMos(c, platform, options)
     }
-    val callGraph = new StandardCallGraph(program)
-
-    val env = new Environment(None, "")
-    env.collectDeclarations(program, options)
-
-    val assemblyOptimizations = optLevel match {
-      case 0 => Nil
-      case 1 => OptimizationPresets.QuickPreset
-      case i if i >= 9 => List(SuperOptimizer)
-      case _ =>
-        val goodExtras = List(
-          if (options.flag(CompilationFlag.EmitEmulation65816Opcodes)) SixteenOptimizations.AllForEmulation else Nil,
-          if (options.flag(CompilationFlag.EmitNative65816Opcodes)) SixteenOptimizations.AllForNative else Nil,
-          if (options.flag(CompilationFlag.ZeropagePseudoregister)) ZeropageRegisterOptimizations.All else Nil,
-        ).flatten
-        val extras = List(
-          if (options.flag(CompilationFlag.EmitIllegals)) UndocumentedOptimizations.All else Nil,
-          if (options.flag(CompilationFlag.Emit65CE02Opcodes)) CE02Optimizations.All else Nil,
-          if (options.flag(CompilationFlag.EmitCmosOpcodes)) CmosOptimizations.All else LaterOptimizations.Nmos,
-          if (options.flag(CompilationFlag.EmitHudsonOpcodes)) HudsonOptimizations.All else Nil,
-          if (options.flag(CompilationFlag.EmitEmulation65816Opcodes)) SixteenOptimizations.AllForEmulation else Nil,
-          if (options.flag(CompilationFlag.EmitNative65816Opcodes)) SixteenOptimizations.AllForNative else Nil,
-          if (options.flag(CompilationFlag.DangerousOptimizations)) DangerousOptimizations.All else Nil,
-        ).flatten
-        val goodCycle = List.fill(optLevel - 2)(OptimizationPresets.Good ++ goodExtras).flatten
-        goodCycle ++ OptimizationPresets.AssOpt ++ extras ++ goodCycle
-    }
-
-    // compile
-    val assembler = new Assembler(program, env, platform)
-    val result = assembler.assemble(callGraph, assemblyOptimizations, options)
-    ErrorReporting.assertNoErrors("Codegen failed")
-    ErrorReporting.debug(f"Unoptimized code size: ${assembler.unoptimizedCodeSize}%5d B")
-    ErrorReporting.debug(f"Optimized code size:   ${assembler.optimizedCodeSize}%5d B")
-    ErrorReporting.debug(f"Gain:                   ${(100L * (assembler.unoptimizedCodeSize - assembler.optimizedCodeSize) / assembler.unoptimizedCodeSize.toDouble).round}%5d%%")
-    ErrorReporting.debug(f"Initialized variables: ${assembler.initializedVariablesSize}%5d B")
 
     if (c.outputAssembly) {
       val path = Paths.get(assOutput)
@@ -174,6 +132,57 @@ object Main {
     }
   }
 
+  private def assembleForMos(c: Context, platform: Platform, options: CompilationOptions): AssemblerOutput = {
+    val optLevel = c.optimizationLevel.getOrElse(0)
+    val unoptimized = new MosSourceLoadingQueue(
+      initialFilenames = c.inputFileNames,
+      includePath = c.includePath,
+      options = options).run()
+
+    val program = if (optLevel > 0) {
+      OptimizationPresets.NodeOpt.foldLeft(unoptimized)((p, opt) => p.applyNodeOptimization(opt, options))
+    } else {
+      unoptimized
+    }
+    val callGraph = new StandardCallGraph(program)
+
+    val env = new Environment(None, "")
+    env.collectDeclarations(program, options)
+
+    val assemblyOptimizations = optLevel match {
+      case 0 => Nil
+      case 1 => OptimizationPresets.QuickPreset
+      case i if i >= 9 => List(SuperOptimizer)
+      case _ =>
+        val goodExtras = List(
+          if (options.flag(CompilationFlag.EmitEmulation65816Opcodes)) SixteenOptimizations.AllForEmulation else Nil,
+          if (options.flag(CompilationFlag.EmitNative65816Opcodes)) SixteenOptimizations.AllForNative else Nil,
+          if (options.flag(CompilationFlag.ZeropagePseudoregister)) ZeropageRegisterOptimizations.All else Nil,
+        ).flatten
+        val extras = List(
+          if (options.flag(CompilationFlag.EmitIllegals)) UndocumentedOptimizations.All else Nil,
+          if (options.flag(CompilationFlag.Emit65CE02Opcodes)) CE02Optimizations.All else Nil,
+          if (options.flag(CompilationFlag.EmitCmosOpcodes)) CmosOptimizations.All else LaterOptimizations.Nmos,
+          if (options.flag(CompilationFlag.EmitHudsonOpcodes)) HudsonOptimizations.All else Nil,
+          if (options.flag(CompilationFlag.EmitEmulation65816Opcodes)) SixteenOptimizations.AllForEmulation else Nil,
+          if (options.flag(CompilationFlag.EmitNative65816Opcodes)) SixteenOptimizations.AllForNative else Nil,
+          if (options.flag(CompilationFlag.DangerousOptimizations)) DangerousOptimizations.All else Nil,
+        ).flatten
+        val goodCycle = List.fill(optLevel - 2)(OptimizationPresets.Good ++ goodExtras).flatten
+        goodCycle ++ OptimizationPresets.AssOpt ++ extras ++ goodCycle
+    }
+
+    // compile
+    val assembler = new MosAssembler(program, env, platform)
+    val result = assembler.assemble(callGraph, assemblyOptimizations, options)
+    ErrorReporting.assertNoErrors("Codegen failed")
+    ErrorReporting.debug(f"Unoptimized code size: ${assembler.unoptimizedCodeSize}%5d B")
+    ErrorReporting.debug(f"Optimized code size:   ${assembler.optimizedCodeSize}%5d B")
+    ErrorReporting.debug(f"Gain:                   ${(100L * (assembler.unoptimizedCodeSize - assembler.optimizedCodeSize) / assembler.unoptimizedCodeSize.toDouble).round}%5d%%")
+    ErrorReporting.debug(f"Initialized variables: ${assembler.initializedVariablesSize}%5d B")
+    result
+  }
+
   private def parser = new CliParser[Context] {
 
     fluff("Main options:", "")

src/main/scala/millfork/OptimizationPresets.scala

@@ -1,6 +1,8 @@
 package millfork
 
-import millfork.assembly.opt._
+import millfork.assembly.AssemblyOptimization
+import millfork.assembly.mos.AssemblyLine
+import millfork.assembly.mos.opt._
 import millfork.node.opt.{UnreachableCode, UnusedFunctions, UnusedGlobalVariables, UnusedLocalVariables}
 
 /**
@@ -13,7 +15,7 @@ object OptimizationPresets {
     UnusedLocalVariables,
     UnusedGlobalVariables,
   )
-  val AssOpt: List[AssemblyOptimization] = List[AssemblyOptimization](
+  val AssOpt: List[AssemblyOptimization[AssemblyLine]] = List[AssemblyOptimization[AssemblyLine]](
     UnusedLabelRemoval,
     AlwaysGoodOptimizations.NonetAddition,
     AlwaysGoodOptimizations.NonetBitOp,
@@ -135,7 +137,7 @@ object OptimizationPresets {
     LaterOptimizations.UseBit,
   )
 
-  val Good: List[AssemblyOptimization] = List[AssemblyOptimization](
+  val Good: List[AssemblyOptimization[AssemblyLine]] = List[AssemblyOptimization[AssemblyLine]](
     UnusedLabelRemoval,
     AlwaysGoodOptimizations.Adc0Optimization,
     AlwaysGoodOptimizations.BitPackingUnpacking,
@@ -204,7 +206,7 @@ object OptimizationPresets {
     VariableToRegisterOptimization,
   )
 
-  val QuickPreset: List[AssemblyOptimization] = List[AssemblyOptimization](
+  val QuickPreset: List[AssemblyOptimization[AssemblyLine]] = List[AssemblyOptimization[AssemblyLine]](
     UnusedLabelRemoval,
     AlwaysGoodOptimizations.Adc0Optimization,
     AlwaysGoodOptimizations.BranchInPlaceRemoval,

src/main/scala/millfork/assembly/AbstractCode.scala

@@ -0,0 +1,12 @@
+package millfork.assembly
+
+import millfork.env.Constant
+
+/**
+  * @author Karol Stasiak
+  */
+trait AbstractCode {
+  def sizeInBytes: Int
+  def isPrintable: Boolean
+  def parameter: Constant
+}

src/main/scala/millfork/assembly/AddrMode.scala

@@ -0,0 +1,58 @@
+package millfork.assembly
+
+/**
+  * @author Karol Stasiak
+  */
+object AddrMode extends Enumeration {
+  val Implied,
+  Immediate,
+  WordImmediate,
+  Relative,
+  LongRelative,
+  ZeroPage,
+  ZeroPageX,
+  ZeroPageY,
+  Absolute,
+  AbsoluteX,
+  AbsoluteY,
+  LongAbsolute,
+  LongAbsoluteX,
+  Indirect,
+  LongIndirect,
+  IndexedX,
+  IndexedY,
+  IndexedSY,
+  IndexedZ,
+  Stack,
+  LongIndexedY,
+  LongIndexedZ,
+  AbsoluteIndexedX,
+  TripleAbsolute,
+  Undecided,
+  RawByte,
+  DoesNotExist = Value
+
+
+  def addrModeToMosString(am: AddrMode.Value, argument: String): String = {
+    am match {
+      case Implied => ""
+      case Immediate => "#" + argument
+      case WordImmediate => "##" + argument
+      case AbsoluteX | ZeroPageX => argument + ", X"
+      case AbsoluteY | ZeroPageY => argument + ", Y"
+      case IndexedX | AbsoluteIndexedX => "(" + argument + ", X)"
+      case Stack => argument + ", S"
+      case IndexedY => "(" + argument + "), Y"
+      case IndexedSY => "(" + argument + ", S), Y"
+      case IndexedZ => "(" + argument + "), Z"
+      case Indirect => "(" + argument + ")"
+      case LongIndexedY => "[" + argument + "], Y"
+      case LongIndexedZ => "[" + argument + "], Z"
+      case LongIndirect => "[" + argument + "]"
+      case ZeroPage => argument // + "\t;zp"
+      case LongAbsolute => "FAR " + argument
+      case LongAbsoluteX => "FAR " + argument + ", X"
+      case _ => argument;
+    }
+  }
+}

src/main/scala/millfork/assembly/AssemblyOptimization.scala

@@ -0,0 +1,13 @@
+package millfork.assembly
+
+import millfork.CompilationOptions
+import millfork.env.NormalFunction
+
+/**
+  * @author Karol Stasiak
+  */
+trait AssemblyOptimization[T <: AbstractCode] {
+  def name: String
+
+  def optimize(f: NormalFunction, code: List[T], options: CompilationOptions): List[T]
+}

src/main/scala/millfork/assembly/mos/AssemblyLine.scala

@@ -1,9 +1,10 @@
-package millfork.assembly
+package millfork.assembly.mos
 
-import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly.Opcode._
-import millfork.compiler.{CompilationContext, MfCompiler}
+import millfork.assembly.{AbstractCode, AddrMode}
+import millfork.assembly.mos.Opcode._
+import millfork.compiler.mos.{CompilationContext, MosCompiler}
 import millfork.env._
+import millfork.{CompilationFlag, CompilationOptions}
 
 //noinspection TypeAnnotation
 object OpcodeClasses {
@@ -378,7 +379,7 @@ object AssemblyLine {
         List(AssemblyLine.immediate(opcode, 0))
       } else if (opcodesForZeroedOrSignExtendedVariableOperation(opcode)) {
         if (variable.typ.isSigned) {
-          val label = MfCompiler.nextLabel("sx")
+          val label = MosCompiler.nextLabel("sx")
           AssemblyLine.variable(ctx, opcode, variable, variable.typ.size - 1) ++ List(
             AssemblyLine.immediate(ORA, 0x7f),
             AssemblyLine.relative(BMI, label),
@@ -453,12 +454,12 @@ object AssemblyLine {
     AssemblyLine(opcode, AddrMode.Stack, NumericConstant(addr & 0xff, 1))
 }
 
-case class AssemblyLine(opcode: Opcode.Value, addrMode: AddrMode.Value, var parameter: Constant, elidable: Boolean = true) {
+case class AssemblyLine(opcode: Opcode.Value, addrMode: AddrMode.Value, var parameter: Constant, elidable: Boolean = true) extends AbstractCode {
 
 
   import AddrMode._
-  import State._
   import OpcodeClasses._
+  import State._
   import Treatment._
 
   def reads(state: State.Value): Boolean = state match {
@@ -521,7 +522,7 @@ case class AssemblyLine(opcode: Opcode.Value, addrMode: AddrMode.Value, var para
     }
   }
 
-  def sizeInBytes: Int = addrMode match {
+  override def sizeInBytes: Int = addrMode match {
     case Implied | RawByte => 1
     case Relative | ZeroPageX | ZeroPage | ZeroPageY | IndexedZ | IndexedX | IndexedY | IndexedSY | Stack | LongIndexedY | LongIndexedZ | Immediate => 2
     case AbsoluteIndexedX | AbsoluteX | Absolute | AbsoluteY | Indirect | LongRelative | WordImmediate => 3
@@ -561,6 +562,6 @@ case class AssemblyLine(opcode: Opcode.Value, addrMode: AddrMode.Value, var para
         case HuSAX => "SAX"
         case _ => opcode.toString
       }
-      s"    $op ${AddrMode.addrModeToString(addrMode, parameter.toString)}"
+      s"    $op ${AddrMode.addrModeToMosString(addrMode, parameter.toString)}"
     }
 }

src/main/scala/millfork/assembly/mos/Opcode.scala

@@ -1,4 +1,4 @@
-package millfork.assembly
+package millfork.assembly.mos
 
 import java.util.Locale
 
@@ -301,56 +301,3 @@ object Opcode extends Enumeration {
 
 }
 
-object AddrMode extends Enumeration {
-  val Implied,
-  Immediate,
-  WordImmediate,
-  Relative,
-  LongRelative,
-  ZeroPage,
-  ZeroPageX,
-  ZeroPageY,
-  Absolute,
-  AbsoluteX,
-  AbsoluteY,
-  LongAbsolute,
-  LongAbsoluteX,
-  Indirect,
-  LongIndirect,
-  IndexedX,
-  IndexedY,
-  IndexedSY,
-  IndexedZ,
-  Stack,
-  LongIndexedY,
-  LongIndexedZ,
-  AbsoluteIndexedX,
-  TripleAbsolute,
-  Undecided,
-  RawByte,
-  DoesNotExist = Value
-
-
-  def addrModeToString(am: AddrMode.Value, argument: String): String = {
-    am match {
-      case Implied => ""
-      case Immediate => "#" + argument
-      case WordImmediate => "##" + argument
-      case AbsoluteX | ZeroPageX => argument + ", X"
-      case AbsoluteY | ZeroPageY => argument + ", Y"
-      case IndexedX | AbsoluteIndexedX => "(" + argument + ", X)"
-      case Stack => argument + ", S"
-      case IndexedY => "(" + argument + "), Y"
-      case IndexedSY => "(" + argument + ", S), Y"
-      case IndexedZ => "(" + argument + "), Z"
-      case Indirect => "(" + argument + ")"
-      case LongIndexedY => "[" + argument + "], Y"
-      case LongIndexedZ => "[" + argument + "], Z"
-      case LongIndirect => "[" + argument + "]"
-      case ZeroPage => argument // + "\t;zp"
-      case LongAbsolute => "FAR " + argument
-      case LongAbsoluteX => "FAR " + argument + ", X"
-      case _ => argument;
-    }
-  }
-}

src/main/scala/millfork/assembly/mos/opt/AlwaysGoodOptimizations.scala

@@ -1,11 +1,12 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import java.util.concurrent.atomic.AtomicInteger
 
+import millfork.assembly.AddrMode
 import millfork.assembly.AddrMode._
-import millfork.assembly.Opcode._
-import millfork.assembly.OpcodeClasses._
-import millfork.assembly.{opt, _}
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.mos.OpcodeClasses._
+import millfork.assembly.mos.{opt, _}
 import millfork.env._
 
 /**

src/main/scala/millfork/assembly/mos/opt/CE02Optimizations.scala

@@ -1,9 +1,8 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.assembly.AddrMode._
-import millfork.assembly.AssemblyLine
-import millfork.assembly.Opcode._
-import millfork.assembly.OpcodeClasses._
+import millfork.assembly.AssemblyOptimization
+import millfork.assembly.mos.AssemblyLine
+import millfork.assembly.mos.Opcode._
 
 /**
   * @author Karol Stasiak
@@ -16,5 +15,5 @@ object CE02Optimizations {
       (Elidable & HasOpcode(ROR)) ~~> (_ => List(AssemblyLine.implied(ASR))),
   )
 
-  val All: List[AssemblyOptimization] = List(UseAsr)
+  val All: List[AssemblyOptimization[AssemblyLine]] = List(UseAsr)
 }

src/main/scala/millfork/assembly/mos/opt/ChangeIndexRegisterOptimization.scala

@@ -1,7 +1,8 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import millfork.CompilationOptions
-import millfork.assembly.{AssemblyLine, OpcodeClasses}
+import millfork.assembly.mos.{AssemblyLine, OpcodeClasses}
+import millfork.assembly.AssemblyOptimization
 import millfork.env.NormalFunction
 import millfork.error.ErrorReporting
 
@@ -12,7 +13,7 @@ import millfork.error.ErrorReporting
 object ChangeIndexRegisterOptimizationPreferringX2Y extends ChangeIndexRegisterOptimization(true)
 object ChangeIndexRegisterOptimizationPreferringY2X extends ChangeIndexRegisterOptimization(false)
 
-class ChangeIndexRegisterOptimization(preferX2Y: Boolean) extends AssemblyOptimization {
+class ChangeIndexRegisterOptimization(preferX2Y: Boolean) extends AssemblyOptimization[AssemblyLine] {
 
   object IndexReg extends Enumeration {
     val X, Y = Value
@@ -25,7 +26,7 @@ class ChangeIndexRegisterOptimization(preferX2Y: Boolean) extends AssemblyOptimi
   import IndexReg._
   import IndexDirection._
   import millfork.assembly.AddrMode._
-  import millfork.assembly.Opcode._
+  import millfork.assembly.mos.Opcode._
 
   type IndexReg = IndexReg.Value
   type IndexDirection = IndexDirection.Value

src/main/scala/millfork/assembly/mos/opt/CmosOptimizations.scala

@@ -1,9 +1,10 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.assembly.{AssemblyLine, Opcode, State}
-import millfork.assembly.Opcode._
+import millfork.assembly.AssemblyOptimization
+import millfork.assembly.mos.{AssemblyLine, Opcode, State}
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
-import millfork.assembly.OpcodeClasses._
+import millfork.assembly.mos.OpcodeClasses._
 import millfork.env._
 
 /**
@@ -49,5 +50,5 @@ object CmosOptimizations {
     (Elidable & HasX(0) & HasZ(0) & HasAddrMode(AbsoluteIndexedX) & HasOpcode(JMP)) ~~> (code => code.map(_.copy(addrMode = Indirect))),
   )
 
-  val All: List[AssemblyOptimization] = List(OptimizeZeroIndex, SimplerBitFlipping, ZeroStoreAsStz)
+  val All: List[AssemblyOptimization[AssemblyLine]] = List(OptimizeZeroIndex, SimplerBitFlipping, ZeroStoreAsStz)
 }

src/main/scala/millfork/assembly/mos/opt/CoarseFlowAnalyzer.scala

@@ -1,7 +1,8 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly._
+import millfork.assembly.mos.AssemblyLine
+import millfork.assembly.mos.OpcodeClasses
 import millfork.env.{Label, MemoryAddressConstant, NormalFunction, NumericConstant}
 
 /**
@@ -32,7 +33,7 @@ object CoarseFlowAnalyzer {
       changed = false
       var currentStatus: CpuStatus = functionStartStatus
       for (i <- codeArray.indices) {
-        import millfork.assembly.Opcode._
+        import millfork.assembly.mos.Opcode._
         import millfork.assembly.AddrMode._
         if (flagArray(i) != currentStatus) {
           changed = true

src/main/scala/millfork/assembly/mos/opt/CpuStatus.scala

@@ -1,6 +1,6 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.assembly.State
+import millfork.assembly.mos.State
 
 /**
   * @author Karol Stasiak

src/main/scala/millfork/assembly/mos/opt/DangerousOptimizations.scala

@@ -1,7 +1,8 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import millfork.assembly._
-import millfork.assembly.Opcode._
+import millfork.assembly.mos._
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
 import millfork.env._
 
@@ -55,5 +56,5 @@ object DangerousOptimizations {
     },
   )
 
-  val All: List[AssemblyOptimization] = List(ConstantIndexOffsetPropagation)
+  val All: List[AssemblyOptimization[AssemblyLine]] = List(ConstantIndexOffsetPropagation)
 }

src/main/scala/millfork/assembly/mos/opt/EmptyMemoryStoreRemoval.scala

@@ -1,9 +1,10 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import millfork.CompilationOptions
-import millfork.assembly.AssemblyLine
+import millfork.assembly.AssemblyOptimization
+import millfork.assembly.mos.AssemblyLine
 import millfork.env._
-import millfork.assembly.Opcode._
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
 import millfork.error.ErrorReporting
 
@@ -12,7 +13,7 @@ import scala.collection.{immutable, mutable}
 /**
   * @author Karol Stasiak
   */
-object EmptyMemoryStoreRemoval extends AssemblyOptimization {
+object EmptyMemoryStoreRemoval extends AssemblyOptimization[AssemblyLine] {
   override def name = "Removing pointless stores to automatic variables"
 
   private val storeAddrModes = Set(Absolute, ZeroPage, AbsoluteX, AbsoluteY, ZeroPageX, ZeroPageY)

src/main/scala/millfork/assembly/mos/opt/FlowAnalyzer.scala

@@ -1,7 +1,7 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly.{AssemblyLine, Opcode, State}
+import millfork.CompilationOptions
+import millfork.assembly.mos.{AssemblyLine, Opcode, State}
 import millfork.env.{Label, MemoryAddressConstant, NormalFunction}
 
 /**

src/main/scala/millfork/assembly/mos/opt/FlowAnalyzerForImmediate.scala

@@ -1,7 +1,7 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.assembly.Opcode
-import millfork.assembly.Opcode._
+import millfork.assembly.mos.Opcode
+import millfork.assembly.mos.Opcode._
 
 /**
   * @author Karol Stasiak

src/main/scala/millfork/assembly/mos/opt/FlowAnalyzerForImplied.scala

@@ -1,7 +1,7 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.assembly.Opcode
-import millfork.assembly.Opcode._
+import millfork.assembly.mos.Opcode
+import millfork.assembly.mos.Opcode._
 
 /**
   * @author Karol Stasiak

src/main/scala/millfork/assembly/mos/opt/FlowAnalyzerForTheRest.scala

@@ -1,7 +1,7 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.assembly.Opcode
-import millfork.assembly.Opcode._
+import millfork.assembly.mos.Opcode
+import millfork.assembly.mos.Opcode._
 
 /**
   * @author Karol Stasiak

src/main/scala/millfork/assembly/mos/opt/HudsonOptimizations.scala

@@ -1,7 +1,8 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.assembly.AssemblyLine
-import millfork.assembly.Opcode._
+import millfork.assembly.AssemblyOptimization
+import millfork.assembly.mos.AssemblyLine
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
 import millfork.env.NumericConstant
 
@@ -10,7 +11,7 @@ import millfork.env.NumericConstant
   */
 object HudsonOptimizations {
 
-  val All: List[AssemblyOptimization] = List()
+  val All: List[AssemblyOptimization[AssemblyLine]] = List()
 
   def removeLoadZero(code: List[AssemblyLine]): List[AssemblyLine] = code.map{
     case AssemblyLine(LDA, Immediate, NumericConstant(0, _), true) => AssemblyLine.implied(CLA)

src/main/scala/millfork/assembly/mos/opt/JumpFixing.scala

@@ -1,13 +1,13 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import java.util.concurrent.atomic.AtomicInteger
 
-import millfork.assembly.Opcode._
-import millfork.assembly.{AddrMode, AssemblyLine, Opcode}
-import millfork.compiler.MfCompiler
+import millfork.assembly.mos.{AssemblyLine, Opcode}
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.AddrMode
 import millfork.env.{Label, MemoryAddressConstant, NormalFunction}
 import millfork.error.ErrorReporting
-import millfork.{CompilationFlag, CompilationOptions}
+import millfork.CompilationOptions
 
 /**
   * @author Karol Stasiak

src/main/scala/millfork/assembly/mos/opt/JumpShortening.scala

@@ -1,8 +1,9 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
+import millfork.assembly.mos.AssemblyLine
 import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly.{AddrMode, AssemblyLine, Opcode}
-import millfork.assembly.Opcode._
+import millfork.assembly.AddrMode
+import millfork.assembly.mos.Opcode._
 import millfork.env.{Label, MemoryAddressConstant, NormalFunction}
 import millfork.error.ErrorReporting
 

src/main/scala/millfork/assembly/mos/opt/LaterOptimizations.scala

@@ -1,9 +1,10 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import millfork.assembly._
-import millfork.assembly.Opcode._
+import millfork.assembly.mos._
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
-import millfork.assembly.OpcodeClasses._
+import millfork.assembly.mos.OpcodeClasses._
 import millfork.env.{Constant, NormalFunction, NumericConstant}
 
 /**

src/main/scala/millfork/assembly/mos/opt/LocalVariableReadOptimization.scala

@@ -1,19 +1,17 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.{CompilationFlag, CompilationOptions, NonOverlappingIntervals}
-import millfork.assembly.{AddrMode, AssemblyLine, OpcodeClasses}
-import millfork.assembly.Opcode._
+import millfork.CompilationOptions
+import millfork.assembly.AssemblyOptimization
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
+import millfork.assembly.mos.{AssemblyLine, OpcodeClasses}
 import millfork.env._
 import millfork.error.ErrorReporting
 
-import scala.annotation.tailrec
-import scala.collection.mutable.ListBuffer
-
 /**
   * @author Karol Stasiak
   */
-object LocalVariableReadOptimization extends AssemblyOptimization {
+object LocalVariableReadOptimization extends AssemblyOptimization[AssemblyLine] {
 
   override def name: String = "Local variable read optimization"
 

src/main/scala/millfork/assembly/mos/opt/LoopUnrolling.scala

@@ -1,11 +1,11 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import java.util.concurrent.atomic.AtomicInteger
 
 import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly.AssemblyLine
-import millfork.assembly.OpcodeClasses._
-import millfork.assembly.Opcode._
+import millfork.assembly.mos.AssemblyLine
+import millfork.assembly.mos.OpcodeClasses._
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
 import millfork.env.{Constant, Label, MemoryAddressConstant}
 

src/main/scala/millfork/assembly/mos/opt/ReverseFlowAnalyzer.scala

@@ -1,10 +1,11 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import millfork.CompilationOptions
 import millfork.assembly._
+import millfork.assembly.mos._
 import millfork.env._
 import millfork.error.ErrorReporting
-import millfork.node.Register
+import millfork.node.MosRegister
 
 import scala.collection.immutable
 
@@ -112,7 +113,7 @@ object ReverseFlowAnalyzer {
       changed = false
       var currentImportance: CpuImportance = finalImportance
       for (i <- codeArray.indices.reverse) {
-        import millfork.assembly.Opcode._
+        import millfork.assembly.mos.Opcode._
         import millfork.assembly.AddrMode._
         if (importanceArray(i) != currentImportance) {
           changed = true
@@ -151,19 +152,19 @@ object ReverseFlowAnalyzer {
             fun.params match {
               case AssemblyParamSignature(params) =>
                 params.foreach(_.variable match {
-                  case RegisterVariable(Register.A, _) =>
+                  case RegisterVariable(MosRegister.A, _) =>
                     result = result.copy(a = Important)
-                  case RegisterVariable(Register.AW, _) =>
+                  case RegisterVariable(MosRegister.AW, _) =>
                     result = result.copy(a = Important, ah = Important)
-                  case RegisterVariable(Register.X, _) =>
+                  case RegisterVariable(MosRegister.X, _) =>
                     result = result.copy(x = Important)
-                  case RegisterVariable(Register.Y, _) =>
+                  case RegisterVariable(MosRegister.Y, _) =>
                     result = result.copy(y = Important)
-                  case RegisterVariable(Register.AX | Register.XA, _) =>
+                  case RegisterVariable(MosRegister.AX | MosRegister.XA, _) =>
                     result = result.copy(a = Important, x = Important)
-                  case RegisterVariable(Register.YA | Register.YA, _) =>
+                  case RegisterVariable(MosRegister.YA | MosRegister.YA, _) =>
                     result = result.copy(a = Important, y = Important)
-                  case RegisterVariable(Register.XY | Register.YX, _) =>
+                  case RegisterVariable(MosRegister.XY | MosRegister.YX, _) =>
                     result = result.copy(x = Important, y = Important)
                   case _ =>
                 })

src/main/scala/millfork/assembly/mos/opt/ReverseFlowAnalyzerPerOpcode.scala

@@ -1,7 +1,7 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.assembly.Opcode
-import millfork.assembly.Opcode._
+import millfork.assembly.mos.Opcode
+import millfork.assembly.mos.Opcode._
 
 /**
   * @author Karol Stasiak

src/main/scala/millfork/assembly/mos/opt/RuleBasedAssemblyOptimization.scala

@@ -1,7 +1,8 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import millfork.{CompilationFlag, CompilationOptions}
 import millfork.assembly._
+import millfork.assembly.mos._
 import millfork.env._
 import millfork.error.ErrorReporting
 
@@ -26,7 +27,7 @@ object FlowInfoRequirement extends Enumeration {
   }
 }
 
-class RuleBasedAssemblyOptimization(val name: String, val needsFlowInfo: FlowInfoRequirement.Value, val rules: AssemblyRule*) extends AssemblyOptimization {
+class RuleBasedAssemblyOptimization(val name: String, val needsFlowInfo: FlowInfoRequirement.Value, val rules: AssemblyRule*) extends AssemblyOptimization[AssemblyLine] {
 
   rules.foreach(_.pattern.validate(needsFlowInfo))
 

src/main/scala/millfork/assembly/mos/opt/SingleAssignmentVariableOptimization.scala

@@ -1,9 +1,10 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import millfork.{CompilationFlag, CompilationOptions, NonOverlappingIntervals}
-import millfork.assembly.{AddrMode, AssemblyLine, Opcode, OpcodeClasses}
-import millfork.assembly.Opcode._
+import millfork.assembly._
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
+import millfork.assembly.mos.{AssemblyLine, Opcode}
 import millfork.env._
 import millfork.error.ErrorReporting
 
@@ -13,7 +14,7 @@ import scala.collection.mutable.ListBuffer
 /**
   * @author Karol Stasiak
   */
-object SingleAssignmentVariableOptimization extends AssemblyOptimization {
+object SingleAssignmentVariableOptimization extends AssemblyOptimization[AssemblyLine] {
 
   private val BadOpcodes = Set(RTS, JSR, JMP, RTI)
   private val GoodOpcodes = Set(

src/main/scala/millfork/assembly/mos/opt/SixteenOptimizations.scala

@@ -1,8 +1,10 @@
-package millfork.assembly.opt
-import millfork.assembly.Opcode._
+package millfork.assembly.mos.opt
+
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
-import millfork.assembly.OpcodeClasses._
-import millfork.assembly.{AssemblyLine, OpcodeClasses, State}
+import millfork.assembly.mos.OpcodeClasses._
+import millfork.assembly.AssemblyOptimization
+import millfork.assembly.mos.{AssemblyLine, OpcodeClasses, State}
 import millfork.env.{Constant, NumericConstant}
 /**
   * @author Karol Stasiak
@@ -216,7 +218,7 @@ object SixteenOptimizations {
 
   // TODO: rewrite most 8-bit optimizations that are applicable to 16-bit code
 
-  val AllForEmulation: List[AssemblyOptimization] = List(
+  val AllForEmulation: List[AssemblyOptimization[AssemblyLine]] = List(
     AccumulatorSwapping,
     OptimizeStackRelative,
     OptimizeZeroIndex,
@@ -224,9 +226,9 @@ object SixteenOptimizations {
     RepSepWeakening,
   )
 
-  val AllForNative: List[AssemblyOptimization] = List(
+  val AllForNative: List[AssemblyOptimization[AssemblyLine]] = List(
     PointlessLoadAfterLoadOrStore
   )
 
-  val All: List[AssemblyOptimization] = AllForEmulation ++ AllForNative
+  val All: List[AssemblyOptimization[AssemblyLine]] = AllForEmulation ++ AllForNative
 }

src/main/scala/millfork/assembly/mos/opt/SizeOptimizations.scala

@@ -1,4 +1,4 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 /**
   * @author Karol Stasiak

src/main/scala/millfork/assembly/mos/opt/SuperOptimizer.scala

@@ -1,7 +1,8 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import millfork.{CompilationFlag, CompilationOptions, OptimizationPresets}
-import millfork.assembly.{AddrMode, AssemblyLine, Opcode}
+import millfork.assembly.{AddrMode, AssemblyOptimization}
+import millfork.assembly.mos.{AssemblyLine, Opcode}
 import millfork.env.NormalFunction
 import millfork.error.ErrorReporting
 
@@ -10,7 +11,7 @@ import scala.collection.mutable
 /**
   * @author Karol Stasiak
   */
-object SuperOptimizer extends AssemblyOptimization {
+object SuperOptimizer extends AssemblyOptimization[AssemblyLine] {
 
   def optimize(m: NormalFunction, code: List[AssemblyLine], options: CompilationOptions): List[AssemblyLine] = {
     val oldVerbosity = ErrorReporting.verbosity
@@ -44,8 +45,8 @@ object SuperOptimizer extends AssemblyOptimization {
       ChangeIndexRegisterOptimizationPreferringX2Y,
       ChangeIndexRegisterOptimizationPreferringY2X)
     val seenSoFar = mutable.Set[CodeView]()
-    val queue = mutable.Queue[(List[AssemblyOptimization], List[AssemblyLine])]()
-    val leaves = mutable.ListBuffer[(List[AssemblyOptimization], List[AssemblyLine])]()
+    val queue = mutable.Queue[(List[AssemblyOptimization[AssemblyLine]], List[AssemblyLine])]()
+    val leaves = mutable.ListBuffer[(List[AssemblyOptimization[AssemblyLine]], List[AssemblyLine])]()
 
     val quickScrub = List(
       UnusedLabelRemoval,

src/main/scala/millfork/assembly/mos/opt/UndocumentedOptimizations.scala

@@ -1,11 +1,12 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import java.util.concurrent.atomic.AtomicInteger
 
 import millfork.assembly._
-import millfork.assembly.Opcode._
+import millfork.assembly.mos._
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
-import millfork.assembly.OpcodeClasses._
+import millfork.assembly.mos.OpcodeClasses._
 import millfork.env.{Constant, NormalFunction, NumericConstant}
 
 /**
@@ -515,7 +516,7 @@ object UndocumentedOptimizations {
     (Elidable & HasOpcode(ANC) & DoesntMatterWhatItDoesWith(State.C)) ~~> (_.map(_.copy(opcode = AND))),
   )
 
-  val All: List[AssemblyOptimization] = List(
+  val All: List[AssemblyOptimization[AssemblyLine]] = List(
     UseLax,
     UseSax,
     UseSbx,

src/main/scala/millfork/assembly/mos/opt/UnusedLabelRemoval.scala

@@ -1,16 +1,16 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import millfork.CompilationOptions
-import millfork.assembly.AddrMode._
-import millfork.assembly.Opcode._
-import millfork.assembly.{AddrMode, AssemblyLine}
+import millfork.assembly.mos.AssemblyLine
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.AssemblyOptimization
 import millfork.env._
 import millfork.error.ErrorReporting
 
 /**
   * @author Karol Stasiak
   */
-object UnusedLabelRemoval extends AssemblyOptimization {
+object UnusedLabelRemoval extends AssemblyOptimization[AssemblyLine] {
 
   override def optimize(f: NormalFunction, code: List[AssemblyLine], options: CompilationOptions): List[AssemblyLine] = {
     val usedLabels = code.flatMap {

src/main/scala/millfork/assembly/mos/opt/VariableLifetime.scala

@@ -1,6 +1,6 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.assembly.AssemblyLine
+import millfork.assembly.mos.AssemblyLine
 import millfork.env._
 import millfork.error.ErrorReporting
 

src/main/scala/millfork/assembly/mos/opt/VariableToRegisterOptimization.scala

@@ -1,8 +1,9 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
 import millfork.{CompilationFlag, CompilationOptions, NonOverlappingIntervals}
-import millfork.assembly.{AddrMode, AssemblyLine, OpcodeClasses}
-import millfork.assembly.Opcode._
+import millfork.assembly.{AddrMode, AssemblyOptimization}
+import millfork.assembly.mos._
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
 import millfork.env._
 import millfork.error.ErrorReporting
@@ -12,7 +13,7 @@ import scala.collection.mutable.ListBuffer
 /**
   * @author Karol Stasiak
   */
-object VariableToRegisterOptimization extends AssemblyOptimization {
+object VariableToRegisterOptimization extends AssemblyOptimization[AssemblyLine] {
 
   object CyclesAndBytes {
     val Zero = CyclesAndBytes(0, 0)

src/main/scala/millfork/assembly/mos/opt/ZeropageRegisterOptimizations.scala

@@ -1,8 +1,9 @@
-package millfork.assembly.opt
+package millfork.assembly.mos.opt
 
-import millfork.assembly.Opcode._
+import millfork.assembly.mos.Opcode._
 import millfork.assembly.AddrMode._
-import millfork.assembly.AssemblyLine
+import millfork.assembly.AssemblyOptimization
+import millfork.assembly.mos.AssemblyLine
 import millfork.env.{CompoundConstant, Constant, MathOperator}
 
 /**
@@ -74,7 +75,7 @@ object ZeropageRegisterOptimizations {
     (Elidable & HasOpcode(STA) & RefersTo("__reg", 1) & DoesntMatterWhatItDoesWithReg(1)) ~~> (_.tail),
   )
 
-  val All: List[AssemblyOptimization] = List(
+  val All: List[AssemblyOptimization[AssemblyLine]] = List(
     ConstantMultiplication,
     DeadRegStore,
     DeadRegStoreFromFlow,

src/main/scala/millfork/assembly/opt/AssemblyOptimization.scala

@@ -1,14 +0,0 @@
-package millfork.assembly.opt
-
-import millfork.CompilationOptions
-import millfork.assembly.AssemblyLine
-import millfork.env.NormalFunction
-
-/**
-  * @author Karol Stasiak
-  */
-trait AssemblyOptimization {
-  def name: String
-
-  def optimize(f: NormalFunction, code: List[AssemblyLine], options: CompilationOptions): List[AssemblyLine]
-}

src/main/scala/millfork/compiler/AbstractCompiler.scala

@@ -0,0 +1,12 @@
+package millfork.compiler
+
+import millfork.assembly.AbstractCode
+import millfork.compiler.mos.CompilationContext
+
+/**
+  * @author Karol Stasiak
+  */
+abstract class AbstractCompiler[T <: AbstractCode] {
+  def nextLabel(prefix: String): String
+  def compile(ctx: CompilationContext): List[T]
+}

src/main/scala/millfork/compiler/AbstractExpressionCompiler.scala

@@ -0,0 +1,99 @@
+package millfork.compiler
+
+import millfork.env._
+import millfork.node._
+import millfork.error.ErrorReporting
+import millfork.assembly.AbstractCode
+import millfork.compiler.mos.CompilationContext
+
+/**
+  * @author Karol Stasiak
+  */
+class AbstractExpressionCompiler[T <: AbstractCode] {
+
+  def getExpressionType(ctx: CompilationContext, expr: Expression): Type = {
+    val env = ctx.env
+    val b = env.get[Type]("byte")
+    val bool = env.get[Type]("bool$")
+    val v = env.get[Type]("void")
+    val w = env.get[Type]("word")
+    expr match {
+      case LiteralExpression(value, size) =>
+        size match {
+          case 1 => b
+          case 2 => w
+          case 3 => env.get[Type]("farword")
+          case 4 => env.get[Type]("long")
+        }
+      case VariableExpression(name) =>
+        env.get[TypedThing](name, expr.position).typ
+      case HalfWordExpression(param, _) =>
+        getExpressionType(ctx, param)
+        b
+      case IndexedExpression(_, _) => b
+      case SeparateBytesExpression(hi, lo) =>
+        if (getExpressionType(ctx, hi).size > 1) ErrorReporting.error("Hi byte too large", hi.position)
+        if (getExpressionType(ctx, lo).size > 1) ErrorReporting.error("Lo byte too large", lo.position)
+        w
+      case SumExpression(params, _) => params.map { case (_, e) => getExpressionType(ctx, e).size }.max match {
+        case 1 => b
+        case 2 => w
+        case _ => ErrorReporting.error("Adding values bigger than words", expr.position); w
+      }
+      case FunctionCallExpression("nonet", params) => w
+      case FunctionCallExpression("not", params) => bool
+      case FunctionCallExpression("hi", params) => b
+      case FunctionCallExpression("lo", params) => b
+      case FunctionCallExpression("*", params) => b
+      case FunctionCallExpression("|" | "&" | "^", params) => params.map { e => getExpressionType(ctx, e).size }.max match {
+        case 1 => b
+        case 2 => w
+        case _ => ErrorReporting.error("Adding values bigger than words", expr.position); w
+      }
+      case FunctionCallExpression("<<", List(a1, a2)) =>
+        if (getExpressionType(ctx, a2).size > 1) ErrorReporting.error("Shift amount too large", a2.position)
+        getExpressionType(ctx, a1)
+      case FunctionCallExpression(">>", List(a1, a2)) =>
+        if (getExpressionType(ctx, a2).size > 1) ErrorReporting.error("Shift amount too large", a2.position)
+        getExpressionType(ctx, a1)
+      case FunctionCallExpression("<<'", params) => b
+      case FunctionCallExpression(">>'", params) => b
+      case FunctionCallExpression(">>>>", params) => b
+      case FunctionCallExpression("&&", params) => bool
+      case FunctionCallExpression("||", params) => bool
+      case FunctionCallExpression("^^", params) => bool
+      case FunctionCallExpression("==", params) => bool
+      case FunctionCallExpression("!=", params) => bool
+      case FunctionCallExpression("<", params) => bool
+      case FunctionCallExpression(">", params) => bool
+      case FunctionCallExpression("<=", params) => bool
+      case FunctionCallExpression(">=", params) => bool
+      case FunctionCallExpression("+=", params) => v
+      case FunctionCallExpression("-=", params) => v
+      case FunctionCallExpression("*=", params) => v
+      case FunctionCallExpression("+'=", params) => v
+      case FunctionCallExpression("-'=", params) => v
+      case FunctionCallExpression("*'=", params) => v
+      case FunctionCallExpression("|=", params) => v
+      case FunctionCallExpression("&=", params) => v
+      case FunctionCallExpression("^=", params) => v
+      case FunctionCallExpression("<<=", params) => v
+      case FunctionCallExpression(">>=", params) => v
+      case FunctionCallExpression("<<'=", params) => v
+      case FunctionCallExpression(">>'=", params) => v
+      case f@FunctionCallExpression(name, params) =>
+        ctx.env.maybeGet[Type](name) match {
+          case Some(typ) =>
+            typ
+          case None =>
+            lookupFunction(ctx, f).returnType
+        }
+    }
+  }
+
+  def lookupFunction(ctx: CompilationContext, f: FunctionCallExpression): MangledFunction = {
+    val paramsWithTypes = f.expressions.map(x => getExpressionType(ctx, x) -> x)
+    ctx.env.lookupFunction(f.functionName, paramsWithTypes).getOrElse(
+      ErrorReporting.fatal(s"Cannot find function `${f.functionName}` with given params `${paramsWithTypes.map(_._1).mkString("(", ",", ")")}`", f.position))
+  }
+}

src/main/scala/millfork/compiler/mos/BranchSpec.scala

@@ -1,4 +1,4 @@
-package millfork.compiler
+package millfork.compiler.mos
 
 /**
   * @author Karol Stasiak

src/main/scala/millfork/compiler/mos/BuiltIns.scala

@@ -1,13 +1,13 @@
-package millfork.compiler
+package millfork.compiler.mos
 
-import millfork.{CompilationFlag, CompilationOptions}
+import millfork.CompilationFlag
+import millfork.assembly.AddrMode._
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.mos._
 import millfork.assembly._
 import millfork.env._
-import millfork.node._
-import millfork.assembly.Opcode._
-import millfork.assembly.AddrMode._
-import millfork.assembly.opt.ConcernsY
 import millfork.error.ErrorReporting
+import millfork.node._
 
 import scala.collection.mutable
 import scala.collection.mutable.ListBuffer
@@ -55,15 +55,15 @@ object BuiltIns {
             case (p: ConstantPointy, _, _, _, None) =>
               Nil -> List(AssemblyLine.absolute(opcode, p.value + constantPart))
             case (p: ConstantPointy, _, 1, IndexChoice.RequireX | IndexChoice.PreferX, Some(v)) =>
-              ExpressionCompiler.compile(ctx, v, Some(b -> RegisterVariable(Register.X, b)), NoBranching) -> List(AssemblyLine.absoluteX(opcode, p.value + constantPart))
+              MosExpressionCompiler.compile(ctx, v, Some(b -> RegisterVariable(MosRegister.X, b)), NoBranching) -> List(AssemblyLine.absoluteX(opcode, p.value + constantPart))
             case (p: ConstantPointy, _, 1, IndexChoice.PreferY, Some(v)) =>
-              ExpressionCompiler.compile(ctx, v, Some(b -> RegisterVariable(Register.Y, b)), NoBranching) -> List(AssemblyLine.absoluteY(opcode, p.value + constantPart))
+              MosExpressionCompiler.compile(ctx, v, Some(b -> RegisterVariable(MosRegister.Y, b)), NoBranching) -> List(AssemblyLine.absoluteY(opcode, p.value + constantPart))
             case (p: VariablePointy, 0 | 1, _, IndexChoice.PreferX | IndexChoice.PreferY, _) =>
-              ExpressionCompiler.compile(ctx, index, Some(b -> RegisterVariable(Register.Y, b)), NoBranching) -> List(AssemblyLine.indexedY(opcode, p.addr))
+              MosExpressionCompiler.compile(ctx, index, Some(b -> RegisterVariable(MosRegister.Y, b)), NoBranching) -> List(AssemblyLine.indexedY(opcode, p.addr))
             case (p: ConstantPointy, _, 2, IndexChoice.PreferX | IndexChoice.PreferY, Some(v)) =>
-              ExpressionCompiler.prepareWordIndexing(ctx, p, index) -> List(AssemblyLine.indexedY(opcode, env.get[VariableInMemory]("__reg")))
+              MosExpressionCompiler.prepareWordIndexing(ctx, p, index) -> List(AssemblyLine.indexedY(opcode, env.get[VariableInMemory]("__reg")))
             case (p: VariablePointy, 2, _, IndexChoice.PreferX | IndexChoice.PreferY, _) =>
-              ExpressionCompiler.prepareWordIndexing(ctx, p, index) -> List(AssemblyLine.indexedY(opcode, env.get[VariableInMemory]("__reg")))
+              MosExpressionCompiler.prepareWordIndexing(ctx, p, index) -> List(AssemblyLine.indexedY(opcode, env.get[VariableInMemory]("__reg")))
             case _ =>
               ErrorReporting.error("Invalid index for simple operation argument", index.position)
               Nil -> Nil
@@ -73,11 +73,11 @@ object BuiltIns {
         case _: FunctionCallExpression | _:SumExpression if commutative =>
           // TODO: is it ok?
           if (ctx.options.flag(CompilationFlag.EmitEmulation65816Opcodes)) {
-            return List(AssemblyLine.implied(PHA)) ++ ExpressionCompiler.compile(ctx.addStack(1), source, Some(b -> RegisterVariable(Register.A, b)), NoBranching) ++ wrapInSedCldIfNeeded(decimal, List(
+            return List(AssemblyLine.implied(PHA)) ++ MosExpressionCompiler.compile(ctx.addStack(1), source, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching) ++ wrapInSedCldIfNeeded(decimal, List(
               AssemblyLine.stackRelative(opcode, 1),
               AssemblyLine.implied(PHX)))
           } else {
-            return List(AssemblyLine.implied(PHA)) ++ ExpressionCompiler.compile(ctx.addStack(1), source, Some(b -> RegisterVariable(Register.A, b)), NoBranching) ++ wrapInSedCldIfNeeded(decimal, List(
+            return List(AssemblyLine.implied(PHA)) ++ MosExpressionCompiler.compile(ctx.addStack(1), source, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching) ++ wrapInSedCldIfNeeded(decimal, List(
               AssemblyLine.implied(TSX),
               AssemblyLine.absoluteX(opcode, 0x101),
               AssemblyLine.implied(INX),
@@ -130,7 +130,7 @@ object BuiltIns {
     val normalizedParams = sortedParams
 
     val h = normalizedParams.head
-    val firstParamCompiled = ExpressionCompiler.compile(ctx, h._2, Some(b -> RegisterVariable(Register.A, b)), NoBranching)
+    val firstParamCompiled = MosExpressionCompiler.compile(ctx, h._2, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)
     val firstParamSignCompiled = if (h._1) {
       // TODO: check if decimal subtraction works correctly here
       List(AssemblyLine.immediate(EOR, 0xff), AssemblyLine.implied(SEC), AssemblyLine.immediate(ADC, 0))
@@ -169,7 +169,7 @@ object BuiltIns {
     val sortedParams = params.sortBy { expr => simplicity(ctx.env, expr) }
 
     val h = sortedParams.head
-    val firstParamCompiled = ExpressionCompiler.compile(ctx, h, Some(b -> RegisterVariable(Register.A, b)), NoBranching)
+    val firstParamCompiled = MosExpressionCompiler.compile(ctx, h, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)
 
     val remainingParamsCompiled = sortedParams.tail.flatMap { p =>
       simpleOperation(opcode, ctx, p, IndexChoice.PreferY, preserveA = true, commutative = true)
@@ -180,17 +180,17 @@ object BuiltIns {
 
   def compileShiftOps(opcode: Opcode.Value, ctx: CompilationContext, l: Expression, r: Expression): List[AssemblyLine] = {
     val b = ctx.env.get[Type]("byte")
-    val firstParamCompiled = ExpressionCompiler.compile(ctx, l, Some(b -> RegisterVariable(Register.A, b)), NoBranching)
+    val firstParamCompiled = MosExpressionCompiler.compile(ctx, l, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)
     ctx.env.eval(r) match {
       case Some(NumericConstant(0, _)) =>
-        ExpressionCompiler.compile(ctx, l, None, NoBranching)
+        MosExpressionCompiler.compile(ctx, l, None, NoBranching)
       case Some(NumericConstant(v, _)) if v > 0 =>
         firstParamCompiled ++ List.fill(v.toInt)(AssemblyLine.implied(opcode))
       case _ =>
-        val compileCounter = ExpressionCompiler.preserveRegisterIfNeeded(ctx, Register.A,
-          ExpressionCompiler.compile(ctx, r, Some(b -> RegisterVariable(Register.X, b)), NoBranching))
-        val labelSkip = MfCompiler.nextLabel("ss")
-        val labelRepeat = MfCompiler.nextLabel("sr")
+        val compileCounter = MosExpressionCompiler.preserveRegisterIfNeeded(ctx, MosRegister.A,
+          MosExpressionCompiler.compile(ctx, r, Some(b -> RegisterVariable(MosRegister.X, b)), NoBranching))
+        val labelSkip = MosCompiler.nextLabel("ss")
+        val labelRepeat = MosCompiler.nextLabel("sr")
         val loop = List(
           AssemblyLine.relative(BEQ, labelSkip),
           AssemblyLine.label(labelRepeat),
@@ -216,7 +216,7 @@ object BuiltIns {
     }
     env.eval(rhs) match {
       case Some(NumericConstant(0, _)) =>
-        ExpressionCompiler.compile(ctx, lhs, None, NoBranching)
+        MosExpressionCompiler.compile(ctx, lhs, None, NoBranching)
       case Some(NumericConstant(shift, _)) if shift > 0 =>
         if (ctx.options.flag(CompilationFlag.RorWarning))
           ErrorReporting.warn("ROR instruction generated", ctx.options, lhs.position)
@@ -230,15 +230,15 @@ object BuiltIns {
   def compileInPlaceByteShiftOps(opcode: Opcode.Value, ctx: CompilationContext, lhs: LhsExpression, rhs: Expression): List[AssemblyLine] = {
     val env = ctx.env
     val b = env.get[Type]("byte")
-    val firstParamCompiled = ExpressionCompiler.compile(ctx, lhs, Some(b -> RegisterVariable(Register.A, b)), NoBranching)
+    val firstParamCompiled = MosExpressionCompiler.compile(ctx, lhs, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)
     env.eval(rhs) match {
       case Some(NumericConstant(0, _)) =>
-        ExpressionCompiler.compile(ctx, lhs, None, NoBranching)
+        MosExpressionCompiler.compile(ctx, lhs, None, NoBranching)
       case Some(NumericConstant(v, _)) if v > 0 =>
         val result = simpleOperation(opcode, ctx, lhs, IndexChoice.RequireX, preserveA = true, commutative = false)
         result ++ List.fill(v.toInt - 1)(result.last)
       case _ =>
-        compileShiftOps(opcode, ctx, lhs, rhs) ++ ExpressionCompiler.compileByteStorage(ctx, Register.A, lhs)
+        compileShiftOps(opcode, ctx, lhs, rhs) ++ MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, lhs)
     }
   }
 
@@ -251,7 +251,7 @@ object BuiltIns {
     // TODO: this probably breaks in case of complex split word expressions
     env.eval(rhs) match {
       case Some(NumericConstant(0, _)) =>
-        ExpressionCompiler.compile(ctx, lhs, None, NoBranching)
+        MosExpressionCompiler.compile(ctx, lhs, None, NoBranching)
       case Some(NumericConstant(shift, _)) if shift > 0 =>
         if (ctx.options.flags(CompilationFlag.EmitNative65816Opcodes)) {
           targetBytes match {
@@ -273,16 +273,16 @@ object BuiltIns {
         val usesX = targetBytes.exists(_.exists(_.concernsX))
         val usesY = targetBytes.exists(_.exists(_.concernsY))
         val (register, decrease) = (usesX, usesY) match {
-          case (true, false) => Register.Y -> DEY
-          case (false, true) => Register.X -> DEX
-          case (false, false) => Register.X -> DEX
+          case (true, false) => MosRegister.Y -> DEY
+          case (false, true) => MosRegister.X -> DEX
+          case (false, false) => MosRegister.X -> DEX
           case (true, true) => ???
         }
 
-        val compileCounter = ExpressionCompiler.preserveRegisterIfNeeded(ctx, Register.A,
-          ExpressionCompiler.compile(ctx, rhs, Some(b -> RegisterVariable(register, b)), NoBranching))
-        val labelSkip = MfCompiler.nextLabel("ss")
-        val labelRepeat = MfCompiler.nextLabel("sr")
+        val compileCounter = MosExpressionCompiler.preserveRegisterIfNeeded(ctx, MosRegister.A,
+          MosExpressionCompiler.compile(ctx, rhs, Some(b -> RegisterVariable(register, b)), NoBranching))
+        val labelSkip = MosCompiler.nextLabel("ss")
+        val labelRepeat = MosCompiler.nextLabel("sr")
 
         if (ctx.options.flags(CompilationFlag.EmitNative65816Opcodes)) {
           targetBytes match {
@@ -323,7 +323,7 @@ object BuiltIns {
     if (simplicity(env, lhs) >= 'J' && simplicity(env, rhs) < 'J') {
       return compileByteComparison(ctx, ComparisonType.flip(compType), rhs, lhs, branches)
     }
-    val firstParamCompiled = ExpressionCompiler.compile(ctx, lhs, Some(b -> RegisterVariable(Register.A, b)), NoBranching)
+    val firstParamCompiled = MosExpressionCompiler.compile(ctx, lhs, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)
     val maybeConstant = env.eval(rhs)
     maybeConstant match {
       case Some(NumericConstant(0, _)) =>
@@ -395,7 +395,7 @@ object BuiltIns {
       case ComparisonType.LessOrEqualUnsigned =>
         List(AssemblyLine.relative(BCC, Label(label)), AssemblyLine.relative(BEQ, Label(label)))
       case ComparisonType.GreaterUnsigned =>
-        val x = MfCompiler.nextLabel("co")
+        val x = MosCompiler.nextLabel("co")
         List(
           AssemblyLine.relative(BEQ, x),
           AssemblyLine.relative(BCS, Label(label)),
@@ -408,7 +408,7 @@ object BuiltIns {
       case ComparisonType.LessOrEqualSigned =>
         List(AssemblyLine.relative(BMI, Label(label)), AssemblyLine.relative(BEQ, Label(label)))
       case ComparisonType.GreaterSigned =>
-        val x = MfCompiler.nextLabel("co")
+        val x = MosCompiler.nextLabel("co")
         List(
           AssemblyLine.relative(BEQ, x),
           AssemblyLine.relative(BPL, Label(label)),
@@ -479,8 +479,8 @@ object BuiltIns {
         ErrorReporting.error("Too complex expressions in comparison", lhs.position)
         (Nil, Nil, Nil, Nil)
     }
-    val lType = ExpressionCompiler.getExpressionType(ctx, lhs)
-    val rType = ExpressionCompiler.getExpressionType(ctx, rhs)
+    val lType = MosExpressionCompiler.getExpressionType(ctx, lhs)
+    val rType = MosExpressionCompiler.getExpressionType(ctx, rhs)
     val compactEqualityComparison = if (ctx.options.flag(CompilationFlag.OptimizeForSpeed)) {
       None
     } else if (lType.size == 1 && !lType.isSigned) {
@@ -495,7 +495,7 @@ object BuiltIns {
         compactEqualityComparison match {
           case Some(code) => code :+ AssemblyLine.relative(BEQ, Label(x))
           case None =>
-            val innerLabel = MfCompiler.nextLabel("cp")
+            val innerLabel = MosCompiler.nextLabel("cp")
             staTo(LDA, ll) ++
               staTo(CMP, rl) ++
               List(AssemblyLine.relative(BNE, innerLabel)) ++
@@ -519,7 +519,7 @@ object BuiltIns {
         }
 
       case ComparisonType.LessUnsigned =>
-        val innerLabel = MfCompiler.nextLabel("cp")
+        val innerLabel = MosCompiler.nextLabel("cp")
         staTo(LDA, lh) ++
           staTo(CMP, rh) ++
           List(
@@ -532,7 +532,7 @@ object BuiltIns {
             AssemblyLine.label(innerLabel))
 
       case ComparisonType.LessOrEqualUnsigned =>
-        val innerLabel = MfCompiler.nextLabel("cp")
+        val innerLabel = MosCompiler.nextLabel("cp")
         staTo(LDA, rh) ++
           staTo(CMP, lh) ++
           List(AssemblyLine.relative(BCC, innerLabel),
@@ -543,7 +543,7 @@ object BuiltIns {
             AssemblyLine.label(innerLabel))
 
       case ComparisonType.GreaterUnsigned =>
-        val innerLabel = MfCompiler.nextLabel("cp")
+        val innerLabel = MosCompiler.nextLabel("cp")
         staTo(LDA, rh) ++
           staTo(CMP, lh) ++
           List(AssemblyLine.relative(BCC, Label(x)),
@@ -554,7 +554,7 @@ object BuiltIns {
             AssemblyLine.label(innerLabel))
 
       case ComparisonType.GreaterOrEqualUnsigned =>
-        val innerLabel = MfCompiler.nextLabel("cp")
+        val innerLabel = MosCompiler.nextLabel("cp")
         staTo(LDA, lh) ++
           staTo(CMP, rh) ++
           List(AssemblyLine.relative(BCC, innerLabel),
@@ -570,7 +570,7 @@ object BuiltIns {
   }
 
   def compileLongComparison(ctx: CompilationContext, compType: ComparisonType.Value, lhs: Expression, rhs: Expression, size:Int, branches: BranchSpec, alreadyFlipped: Boolean = false): List[AssemblyLine] = {
-    val rType = ExpressionCompiler.getExpressionType(ctx, rhs)
+    val rType = MosExpressionCompiler.getExpressionType(ctx, rhs)
     if (rType.size < size && rType.isSigned) {
       if (alreadyFlipped) ???
       else return compileLongComparison(ctx, ComparisonType.flip(compType), rhs, lhs, size, branches, alreadyFlipped = true)
@@ -617,7 +617,7 @@ object BuiltIns {
       case  _ =>
         effectiveComparisonType match {
           case ComparisonType.Equal =>
-            val innerLabel = MfCompiler.nextLabel("cp")
+            val innerLabel = MosCompiler.nextLabel("cp")
             val bytewise = l.zip(r).map{
               case (staL, staR) => staTo(LDA, staL) ++ staTo(CMP, staR)
             }
@@ -658,13 +658,13 @@ object BuiltIns {
     val b = ctx.env.get[Type]("byte")
     ctx.env.eval(addend) match {
       case Some(NumericConstant(0, _)) =>
-        ExpressionCompiler.compile(ctx, v, None, NoBranching) ++ (AssemblyLine.immediate(LDA, 0) :: ExpressionCompiler.compileByteStorage(ctx, Register.A, v))
+        MosExpressionCompiler.compile(ctx, v, None, NoBranching) ++ (AssemblyLine.immediate(LDA, 0) :: MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, v))
       case Some(NumericConstant(1, _)) =>
-        ExpressionCompiler.compile(ctx, v, None, NoBranching)
+        MosExpressionCompiler.compile(ctx, v, None, NoBranching)
       case Some(NumericConstant(x, _)) =>
-        compileByteMultiplication(ctx, v, x.toInt) ++ ExpressionCompiler.compileByteStorage(ctx, Register.A, v)
+        compileByteMultiplication(ctx, v, x.toInt) ++ MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, v)
       case _ =>
-        PseudoregisterBuiltIns.compileByteMultiplication(ctx, Some(v), addend, storeInRegLo = false) ++ ExpressionCompiler.compileByteStorage(ctx, Register.A, v)
+        PseudoregisterBuiltIns.compileByteMultiplication(ctx, Some(v), addend, storeInRegLo = false) ++ MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, v)
     }
   }
 
@@ -727,7 +727,7 @@ object BuiltIns {
       case _ => false
     }
     env.eval(addend) match {
-      case Some(NumericConstant(0, _)) => ExpressionCompiler.compile(ctx, v, None, NoBranching)
+      case Some(NumericConstant(0, _)) => MosExpressionCompiler.compile(ctx, v, None, NoBranching)
       case Some(NumericConstant(1, _)) if lhsIsDirectlyIncrementable && !decimal => if (subtract) {
         simpleOperation(DEC, ctx, v, IndexChoice.RequireX, preserveA = false, commutative = true)
       } else {
@@ -741,25 +741,25 @@ object BuiltIns {
       }
       case _ =>
         if (!subtract && simplicity(env, v) > simplicity(env, addend)) {
-          val loadRhs = ExpressionCompiler.compile(ctx, addend, Some(b -> RegisterVariable(Register.A, b)), NoBranching)
+          val loadRhs = MosExpressionCompiler.compile(ctx, addend, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)
           val modifyAcc = insertBeforeLast(AssemblyLine.implied(CLC), simpleOperation(ADC, ctx, v, IndexChoice.PreferY, preserveA = true, commutative = true, decimal = decimal))
-          val storeLhs = ExpressionCompiler.compileByteStorage(ctx, Register.A, v)
+          val storeLhs = MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, v)
           loadRhs ++ modifyAcc ++ storeLhs
         } else {
-          val loadLhs = ExpressionCompiler.compile(ctx, v, Some(b -> RegisterVariable(Register.A, b)), NoBranching)
+          val loadLhs = MosExpressionCompiler.compile(ctx, v, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)
           val modifyLhs = if (subtract) {
             insertBeforeLast(AssemblyLine.implied(SEC), simpleOperation(SBC, ctx, addend, IndexChoice.PreferY, preserveA = true, commutative = false, decimal = decimal))
           } else {
             insertBeforeLast(AssemblyLine.implied(CLC), simpleOperation(ADC, ctx, addend, IndexChoice.PreferY, preserveA = true, commutative = true, decimal = decimal))
           }
-          val storeLhs = ExpressionCompiler.compileByteStorage(ctx, Register.A, v)
+          val storeLhs = MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, v)
           loadLhs ++ modifyLhs ++ storeLhs
         }
     }
   }
 
   private def getIndexerSize(ctx: CompilationContext, indexExpr: Expression) = {
-    ctx.env.evalVariableAndConstantSubParts(indexExpr)._1.map(v => ExpressionCompiler.getExpressionType(ctx, v)).size
+    ctx.env.evalVariableAndConstantSubParts(indexExpr)._1.map(v => MosExpressionCompiler.getExpressionType(ctx, v)).size
   }
 
   def compileInPlaceWordOrLongAddition(ctx: CompilationContext, lhs: LhsExpression, addend: Expression, subtract: Boolean, decimal: Boolean): List[AssemblyLine] = {
@@ -772,7 +772,7 @@ object BuiltIns {
     val targetBytes: List[List[AssemblyLine]] = getStorageForEachByte(ctx, lhs)
     val lhsIsStack = targetBytes.head.head.opcode == TSX
     val targetSize = targetBytes.size
-    val addendType = ExpressionCompiler.getExpressionType(ctx, addend)
+    val addendType = MosExpressionCompiler.getExpressionType(ctx, addend)
     var addendSize = addendType.size
 
     def isRhsComplex(xs: List[AssemblyLine]): Boolean = xs match {
@@ -795,7 +795,7 @@ object BuiltIns {
       case Nil => Nil
       case x :: Nil => staTo(DEC, x)
       case x :: xs =>
-        val label = MfCompiler.nextLabel("de")
+        val label = MosCompiler.nextLabel("de")
         staTo(LDA, x) ++
           List(AssemblyLine.relative(BNE, label)) ++
           doDec(xs) ++
@@ -805,7 +805,7 @@ object BuiltIns {
 
     val (calculateRhs, addendByteRead0): (List[AssemblyLine], List[List[AssemblyLine]]) = env.eval(addend) match {
       case Some(NumericConstant(0, _)) =>
-        return ExpressionCompiler.compile(ctx, lhs, None, NoBranching)
+        return MosExpressionCompiler.compile(ctx, lhs, None, NoBranching)
       case Some(NumericConstant(1, _)) if canUseIncDec && !subtract =>
         if (ctx.options.flags(CompilationFlag.Emit65CE02Opcodes)) {
           targetBytes match {
@@ -823,7 +823,7 @@ object BuiltIns {
               }
           }
         }
-        val label = MfCompiler.nextLabel("in")
+        val label = MosCompiler.nextLabel("in")
         return staTo(INC, targetBytes.head) ++ targetBytes.tail.flatMap(l => AssemblyLine.relative(BNE, label)::staTo(INC, l)) :+ AssemblyLine.label(label)
       case Some(NumericConstant(-1, _)) if canUseIncDec && subtract =>
         if (ctx.options.flags(CompilationFlag.Emit65CE02Opcodes)) {
@@ -842,7 +842,7 @@ object BuiltIns {
               }
           }
         }
-        val label = MfCompiler.nextLabel("in")
+        val label = MosCompiler.nextLabel("in")
         return staTo(INC, targetBytes.head) ++ targetBytes.tail.flatMap(l => AssemblyLine.relative(BNE, label)::staTo(INC, l)) :+ AssemblyLine.label(label)
       case Some(NumericConstant(1, _)) if canUseIncDec && subtract =>
         if (ctx.options.flags(CompilationFlag.Emit65CE02Opcodes)) {
@@ -861,7 +861,7 @@ object BuiltIns {
               }
           }
         }
-        val label = MfCompiler.nextLabel("de")
+        val label = MosCompiler.nextLabel("de")
         return doDec(targetBytes)
       case Some(NumericConstant(-1, _)) if canUseIncDec && !subtract =>
         if (ctx.options.flags(CompilationFlag.Emit65CE02Opcodes)) {
@@ -880,7 +880,7 @@ object BuiltIns {
               }
           }
         }
-        val label = MfCompiler.nextLabel("de")
+        val label = MosCompiler.nextLabel("de")
         return doDec(targetBytes)
       case Some(constant) =>
         addendSize = targetSize
@@ -888,7 +888,7 @@ object BuiltIns {
       case None =>
         addendSize match {
           case 1 =>
-            val base = ExpressionCompiler.compile(ctx, addend, Some(b -> RegisterVariable(Register.A, b)), NoBranching)
+            val base = MosExpressionCompiler.compile(ctx, addend, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)
             if (subtract) {
               if (isRhsComplex(base)) {
                 if (isRhsStack(base)) {
@@ -903,9 +903,9 @@ object BuiltIns {
               base -> List(Nil)
             }
           case 2 =>
-            val base = ExpressionCompiler.compile(ctx, addend, Some(ExpressionCompiler.getExpressionType(ctx, addend) -> RegisterVariable(Register.AX, w)), NoBranching)
+            val base = MosExpressionCompiler.compile(ctx, addend, Some(MosExpressionCompiler.getExpressionType(ctx, addend) -> RegisterVariable(MosRegister.AX, w)), NoBranching)
             if (isRhsStack(base)) {
-              val fixedBase = ExpressionCompiler.compile(ctx, addend, Some(ExpressionCompiler.getExpressionType(ctx, addend) -> RegisterVariable(Register.AY, w)), NoBranching)
+              val fixedBase = MosExpressionCompiler.compile(ctx, addend, Some(MosExpressionCompiler.getExpressionType(ctx, addend) -> RegisterVariable(MosRegister.AY, w)), NoBranching)
               if (subtract) {
                 ErrorReporting.warn("Subtracting a stack-based value", ctx.options)
                 if (isRhsComplex(base)) {
@@ -932,7 +932,7 @@ object BuiltIns {
                 }
               } else {
                 if (lhsIsStack) {
-                  val fixedBase = ExpressionCompiler.compile(ctx, addend, Some(ExpressionCompiler.getExpressionType(ctx, addend) -> RegisterVariable(Register.AY, w)), NoBranching)
+                  val fixedBase = MosExpressionCompiler.compile(ctx, addend, Some(MosExpressionCompiler.getExpressionType(ctx, addend) -> RegisterVariable(MosRegister.AY, w)), NoBranching)
                   fixedBase -> List(Nil, List(AssemblyLine.implied(TYA)))
                 } else {
                   base -> List(Nil, List(AssemblyLine.implied(TXA)))
@@ -1009,7 +1009,7 @@ object BuiltIns {
       } else {
         if (i >= addendSize) {
           if (addendType.isSigned) {
-            val label = MfCompiler.nextLabel("sx")
+            val label = MosCompiler.nextLabel("sx")
             buffer += AssemblyLine.implied(TXA)
             if (i == addendSize) {
               buffer += AssemblyLine.immediate(ORA, 0x7f)
@@ -1048,14 +1048,14 @@ object BuiltIns {
         Nil
       case _ =>
         if (simplicity(env, v) > simplicity(env, param)) {
-          val loadRhs = ExpressionCompiler.compile(ctx, param, Some(b -> RegisterVariable(Register.A, b)), NoBranching)
+          val loadRhs = MosExpressionCompiler.compile(ctx, param, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)
           val modifyAcc = simpleOperation(operation, ctx, v, IndexChoice.PreferY, preserveA = true, commutative = true)
-          val storeLhs = ExpressionCompiler.compileByteStorage(ctx, Register.A, v)
+          val storeLhs = MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, v)
           loadRhs ++ modifyAcc ++ storeLhs
         } else {
-          val loadLhs = ExpressionCompiler.compile(ctx, v, Some(b -> RegisterVariable(Register.A, b)), NoBranching)
+          val loadLhs = MosExpressionCompiler.compile(ctx, v, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)
           val modifyLhs = simpleOperation(operation, ctx, param, IndexChoice.PreferY, preserveA = true, commutative = true)
-          val storeLhs = ExpressionCompiler.compileByteStorage(ctx, Register.A, v)
+          val storeLhs = MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, v)
           loadLhs ++ modifyLhs ++ storeLhs
         }
     }
@@ -1069,7 +1069,7 @@ object BuiltIns {
     val targetBytes: List[List[AssemblyLine]] = getStorageForEachByte(ctx, lhs)
     val lo = targetBytes.head
     val targetSize = targetBytes.size
-    val paramType = ExpressionCompiler.getExpressionType(ctx, param)
+    val paramType = MosExpressionCompiler.getExpressionType(ctx, param)
     var paramSize = paramType.size
     val extendMultipleBytes = targetSize > paramSize + 1
     val extendAtLeastOneByte = targetSize > paramSize
@@ -1080,10 +1080,10 @@ object BuiltIns {
       case None =>
         paramSize match {
           case 1 =>
-            val base = ExpressionCompiler.compile(ctx, param, Some(b -> RegisterVariable(Register.A, b)), NoBranching)
+            val base = MosExpressionCompiler.compile(ctx, param, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching)
             base -> List(Nil)
           case 2 =>
-            val base = ExpressionCompiler.compile(ctx, param, Some(ExpressionCompiler.getExpressionType(ctx, param) -> RegisterVariable(Register.AX, w)), NoBranching)
+            val base = MosExpressionCompiler.compile(ctx, param, Some(MosExpressionCompiler.getExpressionType(ctx, param) -> RegisterVariable(MosRegister.AX, w)), NoBranching)
             base -> List(Nil, List(AssemblyLine.implied(TXA)))
           case _ => Nil -> (param match {
             case vv: VariableExpression =>
@@ -1120,7 +1120,7 @@ object BuiltIns {
       case (EOR, Some(NumericConstant(0, _)))
            | (ORA, Some(NumericConstant(0, _)))
            | (AND, Some(NumericConstant(AllOnes, _))) =>
-        ExpressionCompiler.compile(ctx, lhs, None, NoBranching)
+        MosExpressionCompiler.compile(ctx, lhs, None, NoBranching)
       case _ =>
         val buffer = mutable.ListBuffer[AssemblyLine]()
         buffer ++= calculateRhs
@@ -1132,7 +1132,7 @@ object BuiltIns {
             }
           } else {
             if (paramType.isSigned) {
-              val label = MfCompiler.nextLabel("sx")
+              val label = MosCompiler.nextLabel("sx")
               buffer += AssemblyLine.implied(TXA)
               if (i == paramSize) {
                 buffer += AssemblyLine.immediate(ORA, 0x7f)
@@ -1163,7 +1163,7 @@ object BuiltIns {
         val variable = env.get[Variable](v.name)
         List.tabulate(variable.typ.size) { i => AssemblyLine.variable(ctx, STA, variable, i) }
       case IndexedExpression(variable, index) =>
-        List(ExpressionCompiler.compileByteStorage(ctx, Register.A, lhs))
+        List(MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, lhs))
       case SeparateBytesExpression(h: LhsExpression, l: LhsExpression) =>
         if (simplicity(ctx.env, h) < 'J' || simplicity(ctx.env, l) < 'J') {
           // a[b]:c[d] is the most complex expression that doesn't cause the following warning
@@ -1171,7 +1171,7 @@ object BuiltIns {
         }
         List(
           getStorageForEachByte(ctx, l).head,
-          ExpressionCompiler.preserveRegisterIfNeeded(ctx, Register.A, getStorageForEachByte(ctx, h).head))
+          MosExpressionCompiler.preserveRegisterIfNeeded(ctx, MosRegister.A, getStorageForEachByte(ctx, h).head))
       case _ =>
         ???
     }
@@ -1189,7 +1189,7 @@ object BuiltIns {
               if (i < variable.typ.size) {
                 AssemblyLine.variable(ctx, STA, variable, i)
               } else if (variable.typ.isSigned) {
-                val label = MfCompiler.nextLabel("sx")
+                val label = MosCompiler.nextLabel("sx")
                 AssemblyLine.variable(ctx, STA, variable, variable.typ.size - 1) ++ List(
                   AssemblyLine.immediate(ORA, 0x7F),
                   AssemblyLine.relative(BMI, label),
@@ -1199,7 +1199,7 @@ object BuiltIns {
             }
           case expr@IndexedExpression(variable, index) =>
             List.tabulate(size) { i =>
-              if (i == 0) ExpressionCompiler.compileByteStorage(ctx, Register.A, expr)
+              if (i == 0) MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, expr)
               else List(AssemblyLine.immediate(STA, 0))
             }
           case SeparateBytesExpression(h: LhsExpression, l: LhsExpression) =>
@@ -1209,7 +1209,7 @@ object BuiltIns {
             }
             List.tabulate(size) { i =>
               if (i == 0) getStorageForEachByte(ctx, l).head
-              else if (i == 1) ExpressionCompiler.preserveRegisterIfNeeded(ctx, Register.A, getStorageForEachByte(ctx, h).head)
+              else if (i == 1) MosExpressionCompiler.preserveRegisterIfNeeded(ctx, MosRegister.A, getStorageForEachByte(ctx, h).head)
               else List(AssemblyLine.immediate(STA, 0))
             }
           case _ =>

src/main/scala/millfork/compiler/mos/ComparisonType.scala

@@ -1,4 +1,4 @@
-package millfork.compiler
+package millfork.compiler.mos
 
 /**
   * @author Karol Stasiak

src/main/scala/millfork/compiler/mos/CompilationContext.scala

@@ -1,7 +1,7 @@
-package millfork.compiler
+package millfork.compiler.mos
 
-import millfork.{CompilationFlag, CompilationOptions}
 import millfork.env.{Environment, Label, NormalFunction}
+import millfork.{CompilationFlag, CompilationOptions}
 
 /**
   * @author Karol Stasiak
@@ -13,7 +13,7 @@ case class CompilationContext(env: Environment,
                               breakLabels: Map[String, Label] = Map(),
                               continueLabels: Map[String, Label] = Map()){
   def withInlinedEnv(environment: Environment): CompilationContext = {
-    val newEnv = new Environment(Some(env), MfCompiler.nextLabel("en"))
+    val newEnv = new Environment(Some(env), MosCompiler.nextLabel("en"))
     newEnv.things ++= environment.things
     copy(env = newEnv)
   }

src/main/scala/millfork/compiler/mos/DecimalBuiltIns.scala

@@ -1,19 +1,13 @@
-package millfork.compiler
+package millfork.compiler.mos
 
-import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly._
-import millfork.env._
-import millfork.node._
-import millfork.assembly.Opcode._
+import millfork.CompilationFlag
 import millfork.assembly.AddrMode._
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.mos._
+import millfork.assembly._
+import millfork.env.{NumericConstant, RegisterVariable, Type, _}
 import millfork.error.ErrorReporting
-
-import scala.collection.mutable
-import scala.collection.mutable.ListBuffer
-import millfork.assembly.AssemblyLine
-import millfork.env.{NumericConstant, RegisterVariable, Type}
-import millfork.error.ErrorReporting
-import millfork.node.{Expression, Register}
+import millfork.node.{Expression, MosRegister, _}
 
 /**
   * @author Karol Stasiak
@@ -34,7 +28,7 @@ object DecimalBuiltIns {
 
   def compileByteShiftRight(ctx: CompilationContext, l: Expression, r: Expression, rotate: Boolean): List[AssemblyLine] = {
     val b = ctx.env.get[Type]("byte")
-    ExpressionCompiler.compile(ctx, l, Some((b, RegisterVariable(Register.A, b))), BranchSpec.None) ++ (ctx.env.eval(r) match {
+    MosExpressionCompiler.compile(ctx, l, Some((b, RegisterVariable(MosRegister.A, b))), BranchSpec.None) ++ (ctx.env.eval(r) match {
       case Some(NumericConstant(0, _)) =>
         Nil
       case Some(NumericConstant(v, _)) =>
@@ -48,11 +42,11 @@ object DecimalBuiltIns {
   }
 
   private def shiftOrRotateAccumulatorRight(ctx: CompilationContext, rotate: Boolean, preserveCarry: Boolean) = {
-    val skipHiDigit = MfCompiler.nextLabel("ds")
-    val skipLoDigit = MfCompiler.nextLabel("ds")
+    val skipHiDigit = MosCompiler.nextLabel("ds")
+    val skipLoDigit = MosCompiler.nextLabel("ds")
     val cmos = ctx.options.flags(CompilationFlag.EmitCmosOpcodes)
     if (preserveCarry) {
-      val constantLabel = MfCompiler.nextLabel("c8")
+      val constantLabel = MosCompiler.nextLabel("c8")
       val bit = if (cmos) {
         AssemblyLine.immediate(BIT, 8)
       } else {
@@ -142,7 +136,7 @@ object DecimalBuiltIns {
         ErrorReporting.error("Cannot multiply by a non-constant amount", r.position)
         return Nil
     }
-    val fullStorage = ExpressionCompiler.compileByteStorage(ctx, Register.A, l)
+    val fullStorage = MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, l)
     val sta = fullStorage.last
     if (sta.opcode != STA) ???
     val fullLoad = fullStorage.init :+ sta.copy(opcode = LDA)

src/main/scala/millfork/compiler/mos/MacroExpander.scala

@@ -1,16 +1,10 @@
-package millfork.compiler
+package millfork.compiler.mos
 
-import java.util.concurrent.atomic.AtomicLong
-
-import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly._
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.mos._
 import millfork.env._
-import millfork.node.{Register, _}
-import millfork.assembly.AddrMode._
-import millfork.assembly.Opcode._
 import millfork.error.ErrorReporting
-
-import scala.collection.JavaConverters._
+import millfork.node.{MosRegister, _}
 /**
   * @author Karol Stasiak
   */
@@ -34,7 +28,7 @@ object MacroExpander {
       case DoWhileStatement(b, i, c, n) => DoWhileStatement(b.map(gx), i.map(gx), f(c), n)
       case ForStatement(v, start, end, dir, body) => ForStatement(h(v), f(start), f(end), dir, body.map(gx))
       case IfStatement(c, t, e) => IfStatement(f(c), t.map(gx), e.map(gx))
-      case s:AssemblyStatement => s.copy(expression =  f(s.expression))
+      case s:MosAssemblyStatement => s.copy(expression =  f(s.expression))
       case Assignment(d,s) => Assignment(fx(d), f(s))
       case BreakStatement(s) => if (s == paramName) BreakStatement(target.toString) else stmt
       case ContinueStatement(s) => if (s == paramName) ContinueStatement(target.toString) else stmt
@@ -57,19 +51,19 @@ object MacroExpander {
                 ctx.env.get[ThingInMemory](vname)
               case l: LhsExpression =>
                 // TODO: ??
-                ExpressionCompiler.compileByteStorage(ctx, Register.A, l)
+                MosExpressionCompiler.compileByteStorage(ctx, MosRegister.A, l)
               case _ =>
                 ErrorReporting.error("A non-assignable expression was passed to an inlineable function as a `ref` parameter", actualParam.position)
             }
             actualCode = actualCode.map {
-              case a@AssemblyStatement(_, _, expr, _) =>
+              case a@MosAssemblyStatement(_, _, expr, _) =>
                 a.copy(expression = expr.replaceVariable(ph, actualParam))
               case x => x
             }
           case (AssemblyParam(typ, Placeholder(ph, phType), AssemblyParameterPassingBehaviour.ByConstant), actualParam) =>
             ctx.env.eval(actualParam).getOrElse(Constant.error("Non-constant expression was passed to an inlineable function as a `const` parameter", actualParam.position))
             actualCode = actualCode.map {
-              case a@AssemblyStatement(_, _, expr, _) =>
+              case a@MosAssemblyStatement(_, _, expr, _) =>
                 a.copy(expression = expr.replaceVariable(ph, actualParam))
               case x => x
             }
@@ -78,7 +72,7 @@ object MacroExpander {
               ErrorReporting.error("Only one macro assembly function parameter can be passed via a register", position)
             }
             hadRegisterParam = true
-            paramPreparation = ExpressionCompiler.compile(ctx, actualParam, Some(typ, v), BranchSpec.None)
+            paramPreparation = MosExpressionCompiler.compile(ctx, actualParam, Some(typ, v), BranchSpec.None)
           case (AssemblyParam(_, _, AssemblyParameterPassingBehaviour.Copy), actualParam) =>
             ???
           case (_, actualParam) =>
@@ -101,12 +95,12 @@ object MacroExpander {
     // fix local labels:
     // TODO: do it even if the labels are in an inline assembly block inside a Millfork function
     val localLabels = actualCode.flatMap{
-      case AssemblyStatement(LABEL, _, VariableExpression(l), _) => Some(l)
+      case MosAssemblyStatement(LABEL, _, VariableExpression(l), _) => Some(l)
       case _ => None
     }.toSet
-    val labelPrefix = MfCompiler.nextLabel("il")
+    val labelPrefix = MosCompiler.nextLabel("il")
     paramPreparation -> actualCode.map{
-      case s@AssemblyStatement(_, _, VariableExpression(v), _) if localLabels(v) =>
+      case s@MosAssemblyStatement(_, _, VariableExpression(v), _) if localLabels(v) =>
         s.copy(expression =  VariableExpression(labelPrefix + v))
       case s => s
     }

src/main/scala/millfork/compiler/mos/MosCompiler.scala

@@ -1,31 +1,27 @@
-package millfork.compiler
+package millfork.compiler.mos
 
 import java.util.concurrent.atomic.AtomicLong
 
-import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly._
+import millfork.CompilationFlag
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.mos._
+import millfork.compiler.AbstractCompiler
 import millfork.env._
-import millfork.node.{Register, _}
-import millfork.assembly.AddrMode._
-import millfork.assembly.Opcode._
-import millfork.error.ErrorReporting
-
-import scala.collection.JavaConverters._
 
 /**
   * @author Karol Stasiak
   */
 //noinspection NotImplementedCode,ScalaUnusedSymbol
-object MfCompiler {
+object MosCompiler extends AbstractCompiler[AssemblyLine] {
 
 
   private val labelCounter = new AtomicLong
 
   def nextLabel(prefix: String): String = "." + prefix + "__" + labelCounter.incrementAndGet().formatted("%05d")
 
-  def compile(ctx: CompilationContext): List[AssemblyLine] = {
+  override def compile(ctx: CompilationContext): List[AssemblyLine] = {
     ctx.env.nameCheck(ctx.function.code)
-    val chunk = StatementCompiler.compile(ctx, ctx.function.code)
+    val chunk = MosStatementCompiler.compile(ctx, ctx.function.code)
 
     val phReg =
       if (ctx.options.flag(CompilationFlag.ZeropagePseudoregister)) {

src/main/scala/millfork/compiler/mos/MosExpressionCompiler.scala

@@ -1,119 +1,38 @@
-package millfork.compiler
+package millfork.compiler.mos
 
-import java.util.concurrent.atomic.AtomicLong
-
-import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly._
-import millfork.env._
-import millfork.node.{Register, _}
+import millfork.CompilationFlag
 import millfork.assembly.AddrMode._
-import millfork.assembly.Opcode._
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.mos._
+import millfork.compiler.AbstractExpressionCompiler
+import millfork.env._
 import millfork.error.ErrorReporting
+import millfork.node.{MosRegister, _}
 /**
   * @author Karol Stasiak
   */
-object ExpressionCompiler {
-
-  def getExpressionType(ctx: CompilationContext, expr: Expression): Type = {
-    val env = ctx.env
-    val b = env.get[Type]("byte")
-    val bool = env.get[Type]("bool$")
-    val v = env.get[Type]("void")
-    val w = env.get[Type]("word")
-    expr match {
-      case LiteralExpression(value, size) =>
-        size match {
-          case 1 => b
-          case 2 => w
-          case 3 => env.get[Type]("farword")
-          case 4 => env.get[Type]("long")
-        }
-      case VariableExpression(name) =>
-        env.get[TypedThing](name, expr.position).typ
-      case HalfWordExpression(param, _) =>
-        getExpressionType(ctx, param)
-        b
-      case IndexedExpression(_, _) => b
-      case SeparateBytesExpression(hi, lo) =>
-        if (getExpressionType(ctx, hi).size > 1) ErrorReporting.error("Hi byte too large", hi.position)
-        if (getExpressionType(ctx, lo).size > 1) ErrorReporting.error("Lo byte too large", lo.position)
-        w
-      case SumExpression(params, _) => params.map { case (_, e) => getExpressionType(ctx, e).size }.max match {
-        case 1 => b
-        case 2 => w
-        case _ => ErrorReporting.error("Adding values bigger than words", expr.position); w
-      }
-      case FunctionCallExpression("nonet", params) => w
-      case FunctionCallExpression("not", params) => bool
-      case FunctionCallExpression("hi", params) => b
-      case FunctionCallExpression("lo", params) => b
-      case FunctionCallExpression("*", params) => b
-      case FunctionCallExpression("|" | "&" | "^", params) => params.map { e => getExpressionType(ctx, e).size }.max match {
-        case 1 => b
-        case 2 => w
-        case _ => ErrorReporting.error("Adding values bigger than words", expr.position); w
-      }
-      case FunctionCallExpression("<<", List(a1, a2)) =>
-        if (getExpressionType(ctx, a2).size > 1) ErrorReporting.error("Shift amount too large", a2.position)
-        getExpressionType(ctx, a1)
-      case FunctionCallExpression(">>", List(a1, a2)) =>
-        if (getExpressionType(ctx, a2).size > 1) ErrorReporting.error("Shift amount too large", a2.position)
-        getExpressionType(ctx, a1)
-      case FunctionCallExpression("<<'", params) => b
-      case FunctionCallExpression(">>'", params) => b
-      case FunctionCallExpression(">>>>", params) => b
-      case FunctionCallExpression("&&", params) => bool
-      case FunctionCallExpression("||", params) => bool
-      case FunctionCallExpression("^^", params) => bool
-      case FunctionCallExpression("==", params) => bool
-      case FunctionCallExpression("!=", params) => bool
-      case FunctionCallExpression("<", params) => bool
-      case FunctionCallExpression(">", params) => bool
-      case FunctionCallExpression("<=", params) => bool
-      case FunctionCallExpression(">=", params) => bool
-      case FunctionCallExpression("+=", params) => v
-      case FunctionCallExpression("-=", params) => v
-      case FunctionCallExpression("*=", params) => v
-      case FunctionCallExpression("+'=", params) => v
-      case FunctionCallExpression("-'=", params) => v
-      case FunctionCallExpression("*'=", params) => v
-      case FunctionCallExpression("|=", params) => v
-      case FunctionCallExpression("&=", params) => v
-      case FunctionCallExpression("^=", params) => v
-      case FunctionCallExpression("<<=", params) => v
-      case FunctionCallExpression(">>=", params) => v
-      case FunctionCallExpression("<<'=", params) => v
-      case FunctionCallExpression(">>'=", params) => v
-      case f@FunctionCallExpression(name, params) =>
-        ctx.env.maybeGet[Type](name) match {
-          case Some(typ) =>
-            typ
-          case None =>
-            lookupFunction(ctx, f).returnType
-        }
-    }
-  }
+object MosExpressionCompiler extends AbstractExpressionCompiler[AssemblyLine] {
 
   def compileConstant(ctx: CompilationContext, expr: Constant, target: Variable): List[AssemblyLine] = {
     target match {
-      case RegisterVariable(Register.A, _) => List(AssemblyLine(LDA, Immediate, expr))
-      case RegisterVariable(Register.AW, _) =>
+      case RegisterVariable(MosRegister.A, _) => List(AssemblyLine(LDA, Immediate, expr))
+      case RegisterVariable(MosRegister.AW, _) =>
         List(
           AssemblyLine.accu16,
           AssemblyLine(LDA_W, WordImmediate, expr),
           AssemblyLine.accu8)
-      case RegisterVariable(Register.X, _) => List(AssemblyLine(LDX, Immediate, expr))
-      case RegisterVariable(Register.Y, _) => List(AssemblyLine(LDY, Immediate, expr))
-      case RegisterVariable(Register.AX, _) => List(
+      case RegisterVariable(MosRegister.X, _) => List(AssemblyLine(LDX, Immediate, expr))
+      case RegisterVariable(MosRegister.Y, _) => List(AssemblyLine(LDY, Immediate, expr))
+      case RegisterVariable(MosRegister.AX, _) => List(
         AssemblyLine(LDA, Immediate, expr.loByte),
         AssemblyLine(LDX, Immediate, expr.hiByte))
-      case RegisterVariable(Register.AY, _) => List(
+      case RegisterVariable(MosRegister.AY, _) => List(
         AssemblyLine(LDA, Immediate, expr.loByte),
         AssemblyLine(LDY, Immediate, expr.hiByte))
-      case RegisterVariable(Register.XA, _) => List(
+      case RegisterVariable(MosRegister.XA, _) => List(
         AssemblyLine(LDA, Immediate, expr.hiByte),
         AssemblyLine(LDX, Immediate, expr.loByte))
-      case RegisterVariable(Register.YA, _) => List(
+      case RegisterVariable(MosRegister.YA, _) => List(
         AssemblyLine(LDA, Immediate, expr.hiByte),
         AssemblyLine(LDY, Immediate, expr.loByte))
       case m: VariableInMemory =>
@@ -160,18 +79,18 @@ object ExpressionCompiler {
     case Nil => Nil
   }
 
-  def preserveRegisterIfNeeded(ctx: CompilationContext, register: Register.Value, code: List[AssemblyLine]): List[AssemblyLine] = {
+  def preserveRegisterIfNeeded(ctx: CompilationContext, register: MosRegister.Value, code: List[AssemblyLine]): List[AssemblyLine] = {
     val state = register match {
-      case Register.A => State.A
-      case Register.X => State.X
-      case Register.Y => State.Y
+      case MosRegister.A => State.A
+      case MosRegister.X => State.X
+      case MosRegister.Y => State.Y
     }
 
     val cmos = ctx.options.flag(CompilationFlag.EmitCmosOpcodes)
     if (AssemblyLine.treatment(code, state) != Treatment.Unchanged) {
       register match {
-        case Register.A => AssemblyLine.implied(PHA) +: fixTsx(code) :+ AssemblyLine.implied(PLA)
-        case Register.X => if (cmos) {
+        case MosRegister.A => AssemblyLine.implied(PHA) +: fixTsx(code) :+ AssemblyLine.implied(PLA)
+        case MosRegister.X => if (cmos) {
           List(
             AssemblyLine.implied(PHA),
             AssemblyLine.implied(PHX),
@@ -190,7 +109,7 @@ object ExpressionCompiler {
             AssemblyLine.implied(PLA),
           )
         }
-        case Register.Y => if (cmos) {
+        case MosRegister.Y => if (cmos) {
           List(
             AssemblyLine.implied(PHA),
             AssemblyLine.implied(PHY),
@@ -222,7 +141,7 @@ object ExpressionCompiler {
       return Nil
     }
     val reg = ctx.env.get[VariableInMemory]("__reg")
-    val compileIndex = compile(ctx, indexExpression, Some(ExpressionCompiler.getExpressionType(ctx, indexExpression) -> RegisterVariable(Register.YA, w)), BranchSpec.None)
+    val compileIndex = compile(ctx, indexExpression, Some(MosExpressionCompiler.getExpressionType(ctx, indexExpression) -> RegisterVariable(MosRegister.YA, w)), BranchSpec.None)
     val prepareRegister = pointy match {
       case ConstantPointy(addr, _) =>
         List(
@@ -242,18 +161,18 @@ object ExpressionCompiler {
     compileIndex ++ prepareRegister
   }
 
-  def compileByteStorage(ctx: CompilationContext, register: Register.Value, target: LhsExpression): List[AssemblyLine] = {
+  def compileByteStorage(ctx: CompilationContext, register: MosRegister.Value, target: LhsExpression): List[AssemblyLine] = {
     val env = ctx.env
     val b = env.get[Type]("byte")
     val store = register match {
-      case Register.A => STA
-      case Register.X => STX
-      case Register.Y => STY
+      case MosRegister.A => STA
+      case MosRegister.X => STX
+      case MosRegister.Y => STY
     }
     val transferToA = register match {
-      case Register.A => NOP
-      case Register.X => TXA
-      case Register.Y => TYA
+      case MosRegister.A => NOP
+      case MosRegister.X => TXA
+      case MosRegister.Y => TYA
     }
     target match {
       case VariableExpression(name) =>
@@ -291,21 +210,21 @@ object ExpressionCompiler {
 
         def storeToArrayAtUnknownIndex(variableIndex: Expression, arrayAddr: Constant) = {
           // TODO check typ
-          val indexRegister = if (register == Register.Y) Register.X else Register.Y
+          val indexRegister = if (register == MosRegister.Y) MosRegister.X else MosRegister.Y
           val calculatingIndex = preserveRegisterIfNeeded(ctx, register, compile(ctx, variableIndex, Some(b, RegisterVariable(indexRegister, b)), NoBranching))
-          if (register == Register.A) {
+          if (register == MosRegister.A) {
             indexRegister match {
-              case Register.Y =>
-                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, Register.Y, indexExpr) ++ List(AssemblyLine.absoluteY(STA, arrayAddr + constIndex))
-              case Register.X =>
-                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, Register.X, indexExpr) ++ List(AssemblyLine.absoluteX(STA, arrayAddr + constIndex))
+              case MosRegister.Y =>
+                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, MosRegister.Y, indexExpr) ++ List(AssemblyLine.absoluteY(STA, arrayAddr + constIndex))
+              case MosRegister.X =>
+                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, MosRegister.X, indexExpr) ++ List(AssemblyLine.absoluteX(STA, arrayAddr + constIndex))
             }
           } else {
             indexRegister match {
-              case Register.Y =>
-                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, Register.Y, indexExpr) ++ List(AssemblyLine.implied(transferToA), AssemblyLine.absoluteY(STA, arrayAddr + constIndex))
-              case Register.X =>
-                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, Register.X, indexExpr) ++ List(AssemblyLine.implied(transferToA), AssemblyLine.absoluteX(STA, arrayAddr + constIndex))
+              case MosRegister.Y =>
+                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, MosRegister.Y, indexExpr) ++ List(AssemblyLine.implied(transferToA), AssemblyLine.absoluteY(STA, arrayAddr + constIndex))
+              case MosRegister.X =>
+                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, MosRegister.X, indexExpr) ++ List(AssemblyLine.implied(transferToA), AssemblyLine.absoluteX(STA, arrayAddr + constIndex))
             }
           }
         }
@@ -313,9 +232,9 @@ object ExpressionCompiler {
           val reg = ctx.env.get[VariableInMemory]("__reg")
           val cmos = ctx.options.flag(CompilationFlag.EmitCmosOpcodes)
           register match {
-            case Register.A =>
+            case MosRegister.A =>
               List(AssemblyLine.implied(PHA)) ++ code ++ List(AssemblyLine.implied(PLA), AssemblyLine.indexedY(STA, reg))
-            case Register.X =>
+            case MosRegister.X =>
               if (code.exists(l => OpcodeClasses.ChangesX(l.opcode))) {
                 if (cmos)
                   List(AssemblyLine.implied(PHX)) ++ code ++ List(AssemblyLine.implied(PLA), AssemblyLine.indexedY(STA, reg))
@@ -324,7 +243,7 @@ object ExpressionCompiler {
               } else {
                 code ++ List(AssemblyLine.implied(TXA), AssemblyLine.indexedY(STA, reg))
               }
-            case Register.Y =>
+            case MosRegister.Y =>
               if (cmos)
                 List(AssemblyLine.implied(PHY)) ++ code ++ List(AssemblyLine.implied(PLA), AssemblyLine.indexedY(STA, reg))
               else
@@ -344,25 +263,25 @@ object ExpressionCompiler {
           //TODO: should there be a type check or a zeropage check?
           case (pointerVariable:VariablePointy, None, _, 0 | 1) =>
             register match {
-              case Register.A =>
+              case MosRegister.A =>
                 List(AssemblyLine.immediate(LDY, constIndex), AssemblyLine.indexedY(STA, pointerVariable.addr))
-              case Register.Y =>
+              case MosRegister.Y =>
                 List(AssemblyLine.implied(TYA), AssemblyLine.immediate(LDY, constIndex), AssemblyLine.indexedY(STA, pointerVariable.addr), AssemblyLine.implied(TAY))
-              case Register.X =>
+              case MosRegister.X =>
                 List(AssemblyLine.immediate(LDY, constIndex), AssemblyLine.implied(TXA), AssemblyLine.indexedY(STA, pointerVariable.addr))
               case _ =>
                 ErrorReporting.error("Cannot store a word in an array", target.position)
                 Nil
             }
           case (pointerVariable:VariablePointy, Some(_), _, 0 | 1) =>
-            val calculatingIndex = compile(ctx, indexExpr, Some(b, RegisterVariable(Register.Y, b)), NoBranching)
+            val calculatingIndex = compile(ctx, indexExpr, Some(b, RegisterVariable(MosRegister.Y, b)), NoBranching)
             register match {
-              case Register.A =>
-                preserveRegisterIfNeeded(ctx, Register.A, calculatingIndex) :+ AssemblyLine.indexedY(STA, pointerVariable.addr)
-              case Register.X =>
-                preserveRegisterIfNeeded(ctx, Register.X, calculatingIndex) ++ List(AssemblyLine.implied(TXA), AssemblyLine.indexedY(STA, pointerVariable.addr))
-              case Register.Y =>
-                AssemblyLine.implied(TYA) :: preserveRegisterIfNeeded(ctx, Register.A, calculatingIndex) ++ List(
+              case MosRegister.A =>
+                preserveRegisterIfNeeded(ctx, MosRegister.A, calculatingIndex) :+ AssemblyLine.indexedY(STA, pointerVariable.addr)
+              case MosRegister.X =>
+                preserveRegisterIfNeeded(ctx, MosRegister.X, calculatingIndex) ++ List(AssemblyLine.implied(TXA), AssemblyLine.indexedY(STA, pointerVariable.addr))
+              case MosRegister.Y =>
+                AssemblyLine.implied(TYA) :: preserveRegisterIfNeeded(ctx, MosRegister.A, calculatingIndex) ++ List(
                   AssemblyLine.indexedY(STA, pointerVariable.addr), AssemblyLine.implied(TAY)
                 )
               case _ =>
@@ -462,8 +381,8 @@ object ExpressionCompiler {
             env.get[TypedThing](name) match {
               case source: VariableInMemory =>
                 target match {
-                  case RegisterVariable(Register.A, _) => AssemblyLine.variable(ctx, LDA, source)
-                  case RegisterVariable(Register.AW, _) =>
+                  case RegisterVariable(MosRegister.A, _) => AssemblyLine.variable(ctx, LDA, source)
+                  case RegisterVariable(MosRegister.AW, _) =>
                     exprType.size match {
                       case 1 => if (exprType.isSigned) {
                         AssemblyLine.variable(ctx, LDA, source) ++ List(
@@ -475,9 +394,9 @@ object ExpressionCompiler {
                         // TODO: use LDA_W
                         AssemblyLine.variable(ctx, LDA, source, 1) ++ List(AssemblyLine.implied(XBA)) ++ AssemblyLine.variable(ctx, LDA, source)
                     }
-                  case RegisterVariable(Register.X, _) => AssemblyLine.variable(ctx, LDX, source)
-                  case RegisterVariable(Register.Y, _) => AssemblyLine.variable(ctx, LDY, source)
-                  case RegisterVariable(Register.AX, _) =>
+                  case RegisterVariable(MosRegister.X, _) => AssemblyLine.variable(ctx, LDX, source)
+                  case RegisterVariable(MosRegister.Y, _) => AssemblyLine.variable(ctx, LDY, source)
+                  case RegisterVariable(MosRegister.AX, _) =>
                     exprType.size match {
                       case 1 => if (exprType.isSigned) {
                         AssemblyLine.variable(ctx, LDA, source) ++ List(
@@ -488,7 +407,7 @@ object ExpressionCompiler {
                       case 2 =>
                         AssemblyLine.variable(ctx, LDA, source) ++ AssemblyLine.variable(ctx, LDX, source, 1)
                     }
-                  case RegisterVariable(Register.AY, _) =>
+                  case RegisterVariable(MosRegister.AY, _) =>
                     exprType.size match {
                       case 1 => if (exprType.isSigned) {
                         AssemblyLine.variable(ctx, LDA, source) ++ List(
@@ -501,7 +420,7 @@ object ExpressionCompiler {
                       case 2 =>
                         AssemblyLine.variable(ctx, LDA, source) ++ AssemblyLine.variable(ctx, LDY, source, 1)
                     }
-                  case RegisterVariable(Register.XA, _) =>
+                  case RegisterVariable(MosRegister.XA, _) =>
                     exprType.size match {
                       case 1 => if (exprType.isSigned) {
                         AssemblyLine.variable(ctx, LDX, source) ++ List(AssemblyLine.implied(TXA)) ++ signExtendA()
@@ -510,7 +429,7 @@ object ExpressionCompiler {
                       case 2 =>
                         AssemblyLine.variable(ctx, LDX, source) ++ AssemblyLine.variable(ctx,LDA, source, 1)
                     }
-                  case RegisterVariable(Register.YA, _) =>
+                  case RegisterVariable(MosRegister.YA, _) =>
                     exprType.size match {
                       case 1 => if (exprType.isSigned) {
                         AssemblyLine.variable(ctx, LDY, source) ++ List(AssemblyLine.implied(TYA)) ++ signExtendA()
@@ -551,10 +470,10 @@ object ExpressionCompiler {
                 }
               case source@StackVariable(_, sourceType, offset) =>
                 target match {
-                  case RegisterVariable(Register.A, _) => List(AssemblyLine.implied(TSX), AssemblyLine.absoluteX(LDA, offset + ctx.extraStackOffset))
-                  case RegisterVariable(Register.X, _) => List(AssemblyLine.implied(TSX), AssemblyLine.absoluteX(LDA, offset + ctx.extraStackOffset), AssemblyLine.implied(TAX))
-                  case RegisterVariable(Register.Y, _) => List(AssemblyLine.implied(TSX), AssemblyLine.absoluteX(LDY, offset + ctx.extraStackOffset))
-                  case RegisterVariable(Register.AX, _) =>
+                  case RegisterVariable(MosRegister.A, _) => List(AssemblyLine.implied(TSX), AssemblyLine.absoluteX(LDA, offset + ctx.extraStackOffset))
+                  case RegisterVariable(MosRegister.X, _) => List(AssemblyLine.implied(TSX), AssemblyLine.absoluteX(LDA, offset + ctx.extraStackOffset), AssemblyLine.implied(TAX))
+                  case RegisterVariable(MosRegister.Y, _) => List(AssemblyLine.implied(TSX), AssemblyLine.absoluteX(LDY, offset + ctx.extraStackOffset))
+                  case RegisterVariable(MosRegister.AX, _) =>
                     exprType.size match {
                       case 1 => if (exprType.isSigned) {
                         List(
@@ -575,10 +494,10 @@ object ExpressionCompiler {
                         AssemblyLine.implied(TAX),
                         AssemblyLine.implied(PLA))
                     }
-                  case RegisterVariable(Register.AY, _) =>
+                  case RegisterVariable(MosRegister.AY, _) =>
                     exprType.size match {
                       case 1 => if (exprType.isSigned) {
-                        val label = MfCompiler.nextLabel("sx")
+                        val label = MosCompiler.nextLabel("sx")
                         ??? // TODO
                       } else {
                         List(
@@ -591,12 +510,12 @@ object ExpressionCompiler {
                         AssemblyLine.absoluteX(LDA, offset + ctx.extraStackOffset),
                         AssemblyLine.absoluteX(LDY, offset + ctx.extraStackOffset + 1))
                     }
-                  case RegisterVariable(Register.XA, _) =>
+                  case RegisterVariable(MosRegister.XA, _) =>
                     ??? // TODO
-                  case RegisterVariable(Register.YA, _) =>
+                  case RegisterVariable(MosRegister.YA, _) =>
                     exprType.size match {
                       case 1 => if (exprType.isSigned) {
-                        val label = MfCompiler.nextLabel("sx")
+                        val label = MosCompiler.nextLabel("sx")
                         ??? // TODO
                       } else {
                         List(
@@ -654,7 +573,7 @@ object ExpressionCompiler {
 
           val register = target match {
             case RegisterVariable(r, _) => r
-            case _ => Register.A
+            case _ => MosRegister.A
           }
           val suffix = target match {
             case RegisterVariable(_, _) => Nil
@@ -672,31 +591,31 @@ object ExpressionCompiler {
               }
           }
           val load = register match {
-            case Register.A | Register.AX | Register.AY => LDA
-            case Register.X => LDX
-            case Register.Y => LDY
+            case MosRegister.A | MosRegister.AX | MosRegister.AY => LDA
+            case MosRegister.X => LDX
+            case MosRegister.Y => LDY
           }
 
           def loadFromArrayAtUnknownIndex(variableIndex: Expression, arrayAddr: Constant) = {
             // TODO check typ
-            val indexRegister = if (register == Register.Y) Register.X else Register.Y
+            val indexRegister = if (register == MosRegister.Y) MosRegister.X else MosRegister.Y
             val calculatingIndex = compile(ctx, variableIndex, Some(b, RegisterVariable(indexRegister, b)), NoBranching)
             indexRegister match {
-              case Register.Y =>
-                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, Register.Y, indexExpr) ++ List(AssemblyLine.absoluteY(load, arrayAddr + constantIndex))
-              case Register.X =>
-                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, Register.X, indexExpr) ++ List(AssemblyLine.absoluteX(load, arrayAddr + constantIndex))
+              case MosRegister.Y =>
+                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, MosRegister.Y, indexExpr) ++ List(AssemblyLine.absoluteY(load, arrayAddr + constantIndex))
+              case MosRegister.X =>
+                calculatingIndex ++ arrayBoundsCheck(ctx, pointy, MosRegister.X, indexExpr) ++ List(AssemblyLine.absoluteX(load, arrayAddr + constantIndex))
             }
           }
 
           def loadFromReg() = {
             val reg = ctx.env.get[VariableInMemory]("__reg")
             register match {
-              case Register.A =>
+              case MosRegister.A =>
                 List(AssemblyLine.indexedY(LDA, reg))
-              case Register.X =>
+              case MosRegister.X =>
                 List(AssemblyLine.indexedY(LDA, reg), AssemblyLine.implied(TAX))
-              case Register.Y =>
+              case MosRegister.Y =>
                 List(AssemblyLine.indexedY(LDA, reg), AssemblyLine.implied(TAY))
             }
           }
@@ -711,21 +630,21 @@ object ExpressionCompiler {
               prepareWordIndexing(ctx, a, indexExpr) ++ loadFromReg()
             case (p:VariablePointy, None, 0 | 1, _) =>
               register match {
-                case Register.A =>
+                case MosRegister.A =>
                   List(AssemblyLine.immediate(LDY, constantIndex), AssemblyLine.indexedY(LDA, p.addr))
-                case Register.Y =>
+                case MosRegister.Y =>
                   List(AssemblyLine.immediate(LDY, constantIndex), AssemblyLine.indexedY(LDA, p.addr), AssemblyLine.implied(TAY))
-                case Register.X =>
+                case MosRegister.X =>
                   List(AssemblyLine.immediate(LDY, constantIndex), AssemblyLine.indexedY(LDA, p.addr), AssemblyLine.implied(TAX))
               }
             case (p:VariablePointy, Some(_), 0 | 1, _) =>
-              val calculatingIndex = compile(ctx, indexExpr, Some(b, RegisterVariable(Register.Y, b)), NoBranching)
+              val calculatingIndex = compile(ctx, indexExpr, Some(b, RegisterVariable(MosRegister.Y, b)), NoBranching)
               register match {
-                case Register.A =>
+                case MosRegister.A =>
                   calculatingIndex :+ AssemblyLine.indexedY(LDA, p.addr)
-                case Register.X =>
+                case MosRegister.X =>
                   calculatingIndex ++ List(AssemblyLine.indexedY(LDA, p.addr), AssemblyLine.implied(TAX))
-                case Register.Y =>
+                case MosRegister.Y =>
                   calculatingIndex ++ List(AssemblyLine.indexedY(LDA, p.addr), AssemblyLine.implied(TAY))
               }
             case _ =>
@@ -733,9 +652,9 @@ object ExpressionCompiler {
               Nil
           }
           register match {
-            case Register.A | Register.X | Register.Y => result ++ suffix
-            case Register.AX => result :+ AssemblyLine.immediate(LDX, 0)
-            case Register.AY => result :+ AssemblyLine.immediate(LDY, 0)
+            case MosRegister.A | MosRegister.X | MosRegister.Y => result ++ suffix
+            case MosRegister.AX => result :+ AssemblyLine.immediate(LDX, 0)
+            case MosRegister.AY => result :+ AssemblyLine.immediate(LDY, 0)
           }
         }
       case SumExpression(params, decimal) =>
@@ -774,19 +693,19 @@ object ExpressionCompiler {
           assertCompatible(exprType, target.typ)
           target match {
             // TODO: some more complex ones may not work correctly
-            case RegisterVariable(Register.A | Register.X | Register.Y, _) => compile(ctx, l, exprTypeAndVariable, branches)
-            case RegisterVariable(Register.AX, _) =>
-              compile(ctx, l, Some(b -> RegisterVariable(Register.A, b)), branches) ++
-                preserveRegisterIfNeeded(ctx, Register.A, compile(ctx, h, Some(b -> RegisterVariable(Register.X, b)), branches))
-            case RegisterVariable(Register.AY, _) =>
-              compile(ctx, l, Some(b -> RegisterVariable(Register.A, b)), branches) ++
-                preserveRegisterIfNeeded(ctx, Register.A, compile(ctx, h, Some(b -> RegisterVariable(Register.Y, b)), branches))
-            case RegisterVariable(Register.XA, _) =>
-              compile(ctx, l, Some(b -> RegisterVariable(Register.X, b)), branches) ++
-                compile(ctx, h, Some(b -> RegisterVariable(Register.A, b)), branches)
-            case RegisterVariable(Register.YA, _) =>
-              compile(ctx, l, Some(b -> RegisterVariable(Register.Y, b)), branches) ++
-                compile(ctx, h, Some(b -> RegisterVariable(Register.A, b)), branches)
+            case RegisterVariable(MosRegister.A | MosRegister.X | MosRegister.Y, _) => compile(ctx, l, exprTypeAndVariable, branches)
+            case RegisterVariable(MosRegister.AX, _) =>
+              compile(ctx, l, Some(b -> RegisterVariable(MosRegister.A, b)), branches) ++
+                preserveRegisterIfNeeded(ctx, MosRegister.A, compile(ctx, h, Some(b -> RegisterVariable(MosRegister.X, b)), branches))
+            case RegisterVariable(MosRegister.AY, _) =>
+              compile(ctx, l, Some(b -> RegisterVariable(MosRegister.A, b)), branches) ++
+                preserveRegisterIfNeeded(ctx, MosRegister.A, compile(ctx, h, Some(b -> RegisterVariable(MosRegister.Y, b)), branches))
+            case RegisterVariable(MosRegister.XA, _) =>
+              compile(ctx, l, Some(b -> RegisterVariable(MosRegister.X, b)), branches) ++
+                compile(ctx, h, Some(b -> RegisterVariable(MosRegister.A, b)), branches)
+            case RegisterVariable(MosRegister.YA, _) =>
+              compile(ctx, l, Some(b -> RegisterVariable(MosRegister.Y, b)), branches) ++
+                compile(ctx, h, Some(b -> RegisterVariable(MosRegister.A, b)), branches)
             case target: VariableInMemory =>
               target.typ.size match {
                 case 1 =>
@@ -827,7 +746,7 @@ object ExpressionCompiler {
                 ErrorReporting.error("Invalid parameter type for hi/lo", param.position)
                 compile(ctx, param, None, BranchSpec.None)
               } else {
-                val compilation = compile(ctx, param, Some(ExpressionCompiler.getExpressionType(ctx, param) -> RegisterVariable(Register.AX, w)), BranchSpec.None)
+                val compilation = compile(ctx, param, Some(MosExpressionCompiler.getExpressionType(ctx, param) -> RegisterVariable(MosRegister.AX, w)), BranchSpec.None)
                 if (hi) {
                   if (typ.size == 2) compilation :+ AssemblyLine.implied(TXA)
                   else if (typ.isSigned) compilation ++ signExtendA()
@@ -853,8 +772,8 @@ object ExpressionCompiler {
                 case _ =>
                   ErrorReporting.warn("Unspecified nonet operation, results might be unpredictable", ctx.options, expr.position)
               }
-              val label = MfCompiler.nextLabel("no")
-              compile(ctx, params.head, Some(b -> RegisterVariable(Register.A, b)), BranchSpec.None) ++ List(
+              val label = MosCompiler.nextLabel("no")
+              compile(ctx, params.head, Some(b -> RegisterVariable(MosRegister.A, b)), BranchSpec.None) ++ List(
                 AssemblyLine.immediate(LDX, 0),
                 AssemblyLine.relative(BCC, label),
                 AssemblyLine.implied(INX),
@@ -867,7 +786,7 @@ object ExpressionCompiler {
               case BranchIfFalse(_) =>
                 params.flatMap(compile(ctx, _, exprTypeAndVariable, branches))
               case _ =>
-                val skip = MfCompiler.nextLabel("an")
+                val skip = MosCompiler.nextLabel("an")
                 params.init.flatMap(compile(ctx, _, exprTypeAndVariable, BranchIfFalse(skip))) ++
                   compile(ctx, params.last, exprTypeAndVariable, branches) ++
                   List(AssemblyLine.label(skip))
@@ -878,7 +797,7 @@ object ExpressionCompiler {
               case BranchIfTrue(_) =>
                 params.flatMap(compile(ctx, _, exprTypeAndVariable, branches))
               case _ =>
-                val skip = MfCompiler.nextLabel("or")
+                val skip = MosCompiler.nextLabel("or")
                 params.init.flatMap(compile(ctx, _, exprTypeAndVariable, BranchIfTrue(skip))) ++
                   compile(ctx, params.last, exprTypeAndVariable, branches) ++
                   List(AssemblyLine.label(skip))
@@ -1096,7 +1015,7 @@ object ExpressionCompiler {
             val (l, r, size) = assertAssignmentLike(ctx, params)
             size match {
               case 1 =>
-                DecimalBuiltIns.compileByteShiftLeft(ctx, l, r, rotate = false) ++ compileByteStorage(ctx, Register.A, l)
+                DecimalBuiltIns.compileByteShiftLeft(ctx, l, r, rotate = false) ++ compileByteStorage(ctx, MosRegister.A, l)
               case i if i >= 2 =>
                 l match {
                   case v: LhsExpression =>
@@ -1107,7 +1026,7 @@ object ExpressionCompiler {
             val (l, r, size) = assertAssignmentLike(ctx, params)
             size match {
               case 1 =>
-                DecimalBuiltIns.compileByteShiftRight(ctx, l, r, rotate = false) ++ compileByteStorage(ctx, Register.A, l)
+                DecimalBuiltIns.compileByteShiftRight(ctx, l, r, rotate = false) ++ compileByteStorage(ctx, MosRegister.A, l)
               case i if i >= 2 =>
                 l match {
                   case v: LhsExpression =>
@@ -1181,7 +1100,7 @@ object ExpressionCompiler {
               case function: MacroFunction =>
                 val (paramPreparation, statements) = MacroExpander.inlineFunction(ctx, function, params, expr.position)
                 paramPreparation ++ statements.map {
-                  case AssemblyStatement(opcode, addrMode, expression, elidable) =>
+                  case MosAssemblyStatement(opcode, addrMode, expression, elidable) =>
                     val param = env.evalForAsm(expression).getOrElse {
                       ErrorReporting.error("Inlining failed due to non-constant things", expression.position)
                       Constant.Zero
@@ -1271,14 +1190,14 @@ object ExpressionCompiler {
   def expressionStorageFromAX(ctx: CompilationContext, exprTypeAndVariable: Option[(Type, Variable)], position: Option[Position]): List[AssemblyLine] = {
     exprTypeAndVariable.fold(noop) {
       case (VoidType, _) => ErrorReporting.fatal("Cannot assign word to void", position)
-      case (_, RegisterVariable(Register.A, _)) => noop
-      case (_, RegisterVariable(Register.AW, _)) => List(AssemblyLine.implied(XBA), AssemblyLine.implied(TXA), AssemblyLine.implied(XBA))
-      case (_, RegisterVariable(Register.X, _)) => List(AssemblyLine.implied(TAX))
-      case (_, RegisterVariable(Register.Y, _)) => List(AssemblyLine.implied(TAY))
-      case (_, RegisterVariable(Register.AX, _)) =>
+      case (_, RegisterVariable(MosRegister.A, _)) => noop
+      case (_, RegisterVariable(MosRegister.AW, _)) => List(AssemblyLine.implied(XBA), AssemblyLine.implied(TXA), AssemblyLine.implied(XBA))
+      case (_, RegisterVariable(MosRegister.X, _)) => List(AssemblyLine.implied(TAX))
+      case (_, RegisterVariable(MosRegister.Y, _)) => List(AssemblyLine.implied(TAY))
+      case (_, RegisterVariable(MosRegister.AX, _)) =>
         // TODO: sign extension
         noop
-      case (_, RegisterVariable(Register.XA, _)) =>
+      case (_, RegisterVariable(MosRegister.XA, _)) =>
         // TODO: sign extension
         if (ctx.options.flag(CompilationFlag.EmitHudsonOpcodes)) {
           List(AssemblyLine.implied(HuSAX))
@@ -1297,12 +1216,12 @@ object ExpressionCompiler {
             AssemblyLine.implied(TAX),
             AssemblyLine.implied(PLA)) // fuck this shit
         }
-      case (_, RegisterVariable(Register.YA, _)) =>
+      case (_, RegisterVariable(MosRegister.YA, _)) =>
         // TODO: sign extension
         List(
           AssemblyLine.implied(TAY),
           AssemblyLine.implied(TXA))
-      case (_, RegisterVariable(Register.AY, _)) =>
+      case (_, RegisterVariable(MosRegister.AY, _)) =>
         // TODO: sign extension
         if (ctx.options.flag(CompilationFlag.EmitHudsonOpcodes)) {
           List(AssemblyLine.implied(SXY))
@@ -1408,23 +1327,17 @@ object ExpressionCompiler {
         // TODO check v.typ
         compile(ctx, source, Some((getExpressionType(ctx, source), v)), NoBranching)
       case SeparateBytesExpression(h: LhsExpression, l: LhsExpression) =>
-        compile(ctx, source, Some(w, RegisterVariable(Register.AX, w)), NoBranching) ++
-          compileByteStorage(ctx, Register.A, l) ++ compileByteStorage(ctx, Register.X, h)
+        compile(ctx, source, Some(w, RegisterVariable(MosRegister.AX, w)), NoBranching) ++
+          compileByteStorage(ctx, MosRegister.A, l) ++ compileByteStorage(ctx, MosRegister.X, h)
       case SeparateBytesExpression(_, _) =>
         ErrorReporting.error("Invalid left-hand-side use of `:`")
         Nil
       case _ =>
-        compile(ctx, source, Some(b, RegisterVariable(Register.A, b)), NoBranching) ++ compileByteStorage(ctx, Register.A, target)
+        compile(ctx, source, Some(b, RegisterVariable(MosRegister.A, b)), NoBranching) ++ compileByteStorage(ctx, MosRegister.A, target)
     }
   }
 
-  def lookupFunction(ctx: CompilationContext, f: FunctionCallExpression): MangledFunction = {
-    val paramsWithTypes = f.expressions.map(x => getExpressionType(ctx, x) -> x)
-    ctx.env.lookupFunction(f.functionName, paramsWithTypes).getOrElse(
-      ErrorReporting.fatal(s"Cannot find function `${f.functionName}` with given params `${paramsWithTypes.map(_._1).mkString("(", ",", ")")}`", f.position))
-  }
-
-  def arrayBoundsCheck(ctx: CompilationContext, pointy: Pointy, register: Register.Value, index: Expression): List[AssemblyLine] = {
+  def arrayBoundsCheck(ctx: CompilationContext, pointy: Pointy, register: MosRegister.Value, index: Expression): List[AssemblyLine] = {
     if (!ctx.options.flags(CompilationFlag.CheckIndexOutOfBounds)) return Nil
     val arrayLength = pointy match {
       case _: VariablePointy => return Nil
@@ -1442,11 +1355,11 @@ object ExpressionCompiler {
       case _ =>
     }
     if (arrayLength > 0 && arrayLength < 255) {
-      val label = MfCompiler.nextLabel("bc")
+      val label = MosCompiler.nextLabel("bc")
       val compare = register match {
-        case Register.A => CMP
-        case Register.X => CPX
-        case Register.Y => CPY
+        case MosRegister.A => CMP
+        case MosRegister.X => CPX
+        case MosRegister.Y => CPY
       }
       List(
         AssemblyLine.implied(PHP),
@@ -1461,7 +1374,7 @@ object ExpressionCompiler {
   }
 
   private def signExtendA(): List[AssemblyLine] = {
-    val label = MfCompiler.nextLabel("sx")
+    val label = MosCompiler.nextLabel("sx")
     List(
       AssemblyLine.immediate(ORA, 0x7F),
       AssemblyLine.relative(BMI, label),

src/main/scala/millfork/compiler/mos/MosStatementCompiler.scala

@@ -1,19 +1,17 @@
-package millfork.compiler
+package millfork.compiler.mos
 
-import java.util.concurrent.atomic.AtomicLong
-
-import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly._
-import millfork.env._
-import millfork.node.{Register, _}
+import millfork.CompilationFlag
 import millfork.assembly.AddrMode._
-import millfork.assembly.Opcode._
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.mos._
+import millfork.env._
 import millfork.error.ErrorReporting
+import millfork.node.{MosRegister, _}
 
 /**
   * @author Karol Stasiak
   */
-object StatementCompiler {
+object MosStatementCompiler {
 
   private def labelChunk(labelName: String) = List(AssemblyLine.label(Label(labelName)))
 
@@ -41,9 +39,9 @@ object StatementCompiler {
           AssemblyLine.zeropage(STA, reg)
         )
       } else Nil
-    val someRegisterA = Some(b, RegisterVariable(Register.A, b))
-    val someRegisterAX = Some(w, RegisterVariable(Register.AX, w))
-    val someRegisterYA = Some(w, RegisterVariable(Register.YA, w))
+    val someRegisterA = Some(b, RegisterVariable(MosRegister.A, b))
+    val someRegisterAX = Some(w, RegisterVariable(MosRegister.AX, w))
+    val someRegisterYA = Some(w, RegisterVariable(MosRegister.YA, w))
     val returnInstructions = if (m.interrupt) {
       if (ctx.options.flag(CompilationFlag.EmitNative65816Opcodes)) {
         if (ctx.options.flag(CompilationFlag.ZeropagePseudoregister)) {
@@ -114,7 +112,7 @@ object StatementCompiler {
       })
     }
     statement match {
-      case AssemblyStatement(o, a, x, e) =>
+      case MosAssemblyStatement(o, a, x, e) =>
         val c: Constant = x match {
           // TODO: hmmm
           case VariableExpression(name) =>
@@ -143,14 +141,14 @@ object StatementCompiler {
           }
         }
       case Assignment(dest, source) =>
-        ExpressionCompiler.compileAssignment(ctx, source, dest)
+        MosExpressionCompiler.compileAssignment(ctx, source, dest)
       case ExpressionStatement(e@FunctionCallExpression(name, params)) =>
-        env.lookupFunction(name, params.map(p => ExpressionCompiler.getExpressionType(ctx, p) -> p)) match {
+        env.lookupFunction(name, params.map(p => MosExpressionCompiler.getExpressionType(ctx, p) -> p)) match {
           case Some(i: MacroFunction) =>
             val (paramPreparation, inlinedStatements) = MacroExpander.inlineFunction(ctx, i, params, e.position)
             paramPreparation ++ compile(ctx.withInlinedEnv(i.environment), inlinedStatements)
           case _ =>
-            ExpressionCompiler.compile(ctx, e, None, NoBranching)
+            MosExpressionCompiler.compile(ctx, e, None, NoBranching)
         }
       case ExpressionStatement(e) =>
         e match {
@@ -158,7 +156,7 @@ object StatementCompiler {
             ErrorReporting.warn("Pointless expression statement", ctx.options, statement.position)
           case _ =>
         }
-        ExpressionCompiler.compile(ctx, e, None, NoBranching)
+        MosExpressionCompiler.compile(ctx, e, None, NoBranching)
       case ReturnStatement(None) =>
         // TODO: return type check
         // TODO: better stackpointer fix
@@ -187,9 +185,9 @@ object StatementCompiler {
                 ErrorReporting.error("Cannot return anything from a void function", statement.position)
                 stackPointerFixBeforeReturn(ctx) ++ returnInstructions
               case 1 =>
-                ExpressionCompiler.compile(ctx, e, someRegisterA, NoBranching) ++ stackPointerFixBeforeReturn(ctx) ++ returnInstructions
+                MosExpressionCompiler.compile(ctx, e, someRegisterA, NoBranching) ++ stackPointerFixBeforeReturn(ctx) ++ returnInstructions
               case 2 =>
-                ExpressionCompiler.compile(ctx, e, someRegisterAX, NoBranching) ++ stackPointerFixBeforeReturn(ctx) ++ returnInstructions
+                MosExpressionCompiler.compile(ctx, e, someRegisterAX, NoBranching) ++ stackPointerFixBeforeReturn(ctx) ++ returnInstructions
             }
           case _ =>
             m.returnType.size match {
@@ -197,14 +195,14 @@ object StatementCompiler {
                 ErrorReporting.error("Cannot return anything from a void function", statement.position)
                 stackPointerFixBeforeReturn(ctx) ++ List(AssemblyLine.discardAF(), AssemblyLine.discardXF(), AssemblyLine.discardYF()) ++ returnInstructions
               case 1 =>
-                ExpressionCompiler.compile(ctx, e, someRegisterA, NoBranching) ++ stackPointerFixBeforeReturn(ctx) ++ List(AssemblyLine.discardXF(), AssemblyLine.discardYF()) ++ returnInstructions
+                MosExpressionCompiler.compile(ctx, e, someRegisterA, NoBranching) ++ stackPointerFixBeforeReturn(ctx) ++ List(AssemblyLine.discardXF(), AssemblyLine.discardYF()) ++ returnInstructions
               case 2 =>
                 // TODO: ???
                 val stackPointerFix = stackPointerFixBeforeReturn(ctx)
                 if (stackPointerFix.isEmpty) {
-                  ExpressionCompiler.compile(ctx, e, someRegisterAX, NoBranching) ++ List(AssemblyLine.discardYF()) ++ returnInstructions
+                  MosExpressionCompiler.compile(ctx, e, someRegisterAX, NoBranching) ++ List(AssemblyLine.discardYF()) ++ returnInstructions
                 } else {
-                  ExpressionCompiler.compile(ctx, e, someRegisterYA, NoBranching) ++
+                  MosExpressionCompiler.compile(ctx, e, someRegisterYA, NoBranching) ++
                     stackPointerFix ++
                     List(AssemblyLine.implied(TAX), AssemblyLine.implied(TYA), AssemblyLine.discardYF()) ++
                     returnInstructions
@@ -212,103 +210,103 @@ object StatementCompiler {
             }
         }
       case IfStatement(condition, thenPart, elsePart) =>
-        val condType = ExpressionCompiler.getExpressionType(ctx, condition)
+        val condType = MosExpressionCompiler.getExpressionType(ctx, condition)
         val thenBlock = compile(ctx, thenPart)
         val elseBlock = compile(ctx, elsePart)
         val largeThenBlock = thenBlock.map(_.sizeInBytes).sum > 100
         val largeElseBlock = elseBlock.map(_.sizeInBytes).sum > 100
         condType match {
           case ConstantBooleanType(_, true) =>
-            ExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching) ++ thenBlock
+            MosExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching) ++ thenBlock
           case ConstantBooleanType(_, false) =>
-            ExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching) ++ elseBlock
+            MosExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching) ++ elseBlock
           case FlagBooleanType(_, jumpIfTrue, jumpIfFalse) =>
             (thenPart, elsePart) match {
               case (Nil, Nil) =>
-                ExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
+                MosExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
               case (Nil, _) =>
-                val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
+                val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
                 if (largeElseBlock) {
-                  val middle = MfCompiler.nextLabel("el")
-                  val end = MfCompiler.nextLabel("fi")
+                  val middle = MosCompiler.nextLabel("el")
+                  val end = MosCompiler.nextLabel("fi")
                   List(conditionBlock, branchChunk(jumpIfFalse, middle), jmpChunk(end), labelChunk(middle), elseBlock, labelChunk(end)).flatten
                 } else {
-                  val end = MfCompiler.nextLabel("fi")
+                  val end = MosCompiler.nextLabel("fi")
                   List(conditionBlock, branchChunk(jumpIfTrue, end), elseBlock, labelChunk(end)).flatten
                 }
               case (_, Nil) =>
-                val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
+                val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
                 if (largeThenBlock) {
-                  val middle = MfCompiler.nextLabel("th")
-                  val end = MfCompiler.nextLabel("fi")
+                  val middle = MosCompiler.nextLabel("th")
+                  val end = MosCompiler.nextLabel("fi")
                   List(conditionBlock, branchChunk(jumpIfTrue, middle), jmpChunk(end), labelChunk(middle), thenBlock, labelChunk(end)).flatten
                 } else {
-                  val end = MfCompiler.nextLabel("fi")
+                  val end = MosCompiler.nextLabel("fi")
                   List(conditionBlock, branchChunk(jumpIfFalse, end), thenBlock, labelChunk(end)).flatten
                 }
               case _ =>
-                val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
+                val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
                 if (largeThenBlock) {
                   if (largeElseBlock) {
-                    val middleT = MfCompiler.nextLabel("th")
-                    val middleE = MfCompiler.nextLabel("el")
-                    val end = MfCompiler.nextLabel("fi")
+                    val middleT = MosCompiler.nextLabel("th")
+                    val middleE = MosCompiler.nextLabel("el")
+                    val end = MosCompiler.nextLabel("fi")
                     List(conditionBlock, branchChunk(jumpIfTrue, middleT), jmpChunk(middleE), labelChunk(middleT), thenBlock, jmpChunk(end), labelChunk(middleE), elseBlock, labelChunk(end)).flatten
                   } else {
-                    val middle = MfCompiler.nextLabel("th")
-                    val end = MfCompiler.nextLabel("fi")
+                    val middle = MosCompiler.nextLabel("th")
+                    val end = MosCompiler.nextLabel("fi")
                     List(conditionBlock, branchChunk(jumpIfTrue, middle), elseBlock, jmpChunk(end), labelChunk(middle), thenBlock, labelChunk(end)).flatten
                   }
                 } else {
-                  val middle = MfCompiler.nextLabel("el")
-                  val end = MfCompiler.nextLabel("fi")
+                  val middle = MosCompiler.nextLabel("el")
+                  val end = MosCompiler.nextLabel("fi")
                   List(conditionBlock, branchChunk(jumpIfFalse, middle), thenBlock, jmpChunk(end), labelChunk(middle), elseBlock, labelChunk(end)).flatten
                 }
             }
           case BuiltInBooleanType =>
             (thenPart, elsePart) match {
               case (Nil, Nil) =>
-                ExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
+                MosExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
               case (Nil, _) =>
                 if (largeElseBlock) {
-                  val middle = MfCompiler.nextLabel("el")
-                  val end = MfCompiler.nextLabel("fi")
-                  val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfFalse(middle))
+                  val middle = MosCompiler.nextLabel("el")
+                  val end = MosCompiler.nextLabel("fi")
+                  val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfFalse(middle))
                   List(conditionBlock, jmpChunk(end), labelChunk(middle), elseBlock, labelChunk(end)).flatten
                 } else {
-                  val end = MfCompiler.nextLabel("fi")
-                  val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(end))
+                  val end = MosCompiler.nextLabel("fi")
+                  val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(end))
                   List(conditionBlock, elseBlock, labelChunk(end)).flatten
                 }
               case (_, Nil) =>
                 if (largeThenBlock) {
-                  val middle = MfCompiler.nextLabel("th")
-                  val end = MfCompiler.nextLabel("fi")
-                  val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(middle))
+                  val middle = MosCompiler.nextLabel("th")
+                  val end = MosCompiler.nextLabel("fi")
+                  val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(middle))
                   List(conditionBlock, jmpChunk(end), labelChunk(middle), thenBlock, labelChunk(end)).flatten
                 } else {
-                  val end = MfCompiler.nextLabel("fi")
-                  val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfFalse(end))
+                  val end = MosCompiler.nextLabel("fi")
+                  val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfFalse(end))
                   List(conditionBlock, thenBlock, labelChunk(end)).flatten
                 }
               case _ =>
                 if (largeThenBlock) {
                   if (largeElseBlock) {
-                    val middleT = MfCompiler.nextLabel("th")
-                    val middleE = MfCompiler.nextLabel("el")
-                    val end = MfCompiler.nextLabel("fi")
-                    val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(middleT))
+                    val middleT = MosCompiler.nextLabel("th")
+                    val middleE = MosCompiler.nextLabel("el")
+                    val end = MosCompiler.nextLabel("fi")
+                    val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(middleT))
                     List(conditionBlock, jmpChunk(middleE), labelChunk(middleT), thenBlock, jmpChunk(end), labelChunk(middleE), elseBlock, labelChunk(end)).flatten
                   } else {
-                    val middle = MfCompiler.nextLabel("th")
-                    val end = MfCompiler.nextLabel("fi")
-                    val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(middle))
+                    val middle = MosCompiler.nextLabel("th")
+                    val end = MosCompiler.nextLabel("fi")
+                    val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(middle))
                     List(conditionBlock, elseBlock, jmpChunk(end), labelChunk(middle), thenBlock, labelChunk(end)).flatten
                   }
                 } else {
-                  val middle = MfCompiler.nextLabel("el")
-                  val end = MfCompiler.nextLabel("fi")
-                  val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfFalse(middle))
+                  val middle = MosCompiler.nextLabel("el")
+                  val end = MosCompiler.nextLabel("fi")
+                  val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfFalse(middle))
                   List(conditionBlock, thenBlock, jmpChunk(end), labelChunk(middle), elseBlock, labelChunk(end)).flatten
                 }
             }
@@ -317,11 +315,11 @@ object StatementCompiler {
             Nil
         }
       case WhileStatement(condition, bodyPart, incrementPart, labels) =>
-        val start = MfCompiler.nextLabel("wh")
-        val middle = MfCompiler.nextLabel("he")
-        val inc = MfCompiler.nextLabel("fp")
-        val end = MfCompiler.nextLabel("ew")
-        val condType = ExpressionCompiler.getExpressionType(ctx, condition)
+        val start = MosCompiler.nextLabel("wh")
+        val middle = MosCompiler.nextLabel("he")
+        val inc = MosCompiler.nextLabel("fp")
+        val end = MosCompiler.nextLabel("ew")
+        val condType = MosExpressionCompiler.getExpressionType(ctx, condition)
         val bodyBlock = compile(ctx.addLabels(labels, Label(end), Label(inc)), bodyPart)
         val incrementBlock = compile(ctx.addLabels(labels, Label(end), Label(inc)), incrementPart)
         val largeBodyBlock = bodyBlock.map(_.sizeInBytes).sum + incrementBlock.map(_.sizeInBytes).sum > 100
@@ -331,19 +329,19 @@ object StatementCompiler {
           case ConstantBooleanType(_, false) => Nil
           case FlagBooleanType(_, jumpIfTrue, jumpIfFalse) =>
             if (largeBodyBlock) {
-              val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
+              val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
               List(labelChunk(start), conditionBlock, branchChunk(jumpIfTrue, middle), jmpChunk(end), labelChunk(middle), bodyBlock, labelChunk(inc), incrementBlock, jmpChunk(start), labelChunk(end)).flatten
             } else {
-              val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
+              val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
               List(jmpChunk(middle), labelChunk(start), bodyBlock, labelChunk(inc), incrementBlock, labelChunk(middle), conditionBlock,  branchChunk(jumpIfTrue, start), labelChunk(end)).flatten
 //              List(labelChunk(start), conditionBlock, branchChunk(jumpIfFalse, end), bodyBlock, labelChunk(inc), incrementBlock, jmpChunk(start), labelChunk(end)).flatten
             }
           case BuiltInBooleanType =>
             if (largeBodyBlock) {
-              val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(middle))
+              val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(middle))
               List(labelChunk(start), conditionBlock, jmpChunk(end), labelChunk(middle), bodyBlock, labelChunk(inc), incrementBlock, jmpChunk(start), labelChunk(end)).flatten
             } else {
-              val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(start))
+              val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(start))
               List(jmpChunk(middle), labelChunk(start), bodyBlock, labelChunk(inc), incrementBlock, labelChunk(middle), conditionBlock, labelChunk(end)).flatten
 //              List(labelChunk(start), conditionBlock, bodyBlock, labelChunk(inc), incrementBlock, jmpChunk(start), labelChunk(end)).flatten
             }
@@ -352,21 +350,21 @@ object StatementCompiler {
             Nil
         }
       case DoWhileStatement(bodyPart, incrementPart, condition, labels) =>
-        val start = MfCompiler.nextLabel("do")
-        val inc = MfCompiler.nextLabel("fp")
-        val end = MfCompiler.nextLabel("od")
-        val condType = ExpressionCompiler.getExpressionType(ctx, condition)
+        val start = MosCompiler.nextLabel("do")
+        val inc = MosCompiler.nextLabel("fp")
+        val end = MosCompiler.nextLabel("od")
+        val condType = MosExpressionCompiler.getExpressionType(ctx, condition)
         val bodyBlock = compile(ctx.addLabels(labels, Label(end), Label(inc)), bodyPart)
         val incrementBlock = compile(ctx.addLabels(labels, Label(end), Label(inc)), incrementPart)
         val largeBodyBlock = bodyBlock.map(_.sizeInBytes).sum + incrementBlock.map(_.sizeInBytes).sum > 100
         condType match {
           case ConstantBooleanType(_, true) =>
-            val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
+            val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
             List(labelChunk(start),bodyBlock, labelChunk(inc), incrementBlock, jmpChunk(start), labelChunk(end)).flatten
           case ConstantBooleanType(_, false) =>
             List(bodyBlock, labelChunk(inc), incrementBlock, labelChunk(end)).flatten
           case FlagBooleanType(_, jumpIfTrue, jumpIfFalse) =>
-            val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
+            val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, NoBranching)
             if (largeBodyBlock) {
               List(labelChunk(start), bodyBlock, labelChunk(inc), incrementBlock, conditionBlock, branchChunk(jumpIfFalse, end), jmpChunk(start), labelChunk(end)).flatten
             } else {
@@ -374,10 +372,10 @@ object StatementCompiler {
             }
           case BuiltInBooleanType =>
             if (largeBodyBlock) {
-              val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfFalse(end))
+              val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfFalse(end))
               List(labelChunk(start), bodyBlock, labelChunk(inc), incrementBlock, conditionBlock, jmpChunk(start), labelChunk(end)).flatten
             } else {
-              val conditionBlock = ExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(start))
+              val conditionBlock = MosExpressionCompiler.compile(ctx, condition, someRegisterA, BranchIfTrue(start))
               List(labelChunk(start), bodyBlock, labelChunk(inc), incrementBlock, conditionBlock, labelChunk(end)).flatten
             }
           case _ =>
@@ -395,13 +393,13 @@ object StatementCompiler {
         (direction, env.eval(start), env.eval(end)) match {
 
           case (ForDirection.Until | ForDirection.ParallelUntil, Some(NumericConstant(s, ssize)), Some(NumericConstant(e, _))) if s == e - 1 =>
-            val end = MfCompiler.nextLabel("of")
+            val end = MosCompiler.nextLabel("of")
             compile(ctx.addLabels(names, Label(end), Label(end)), Assignment(vex, f.start) :: f.body) ++ labelChunk(end)
           case (ForDirection.Until | ForDirection.ParallelUntil, Some(NumericConstant(s, ssize)), Some(NumericConstant(e, _))) if s >= e =>
             Nil
 
           case (ForDirection.To | ForDirection.ParallelTo, Some(NumericConstant(s, ssize)), Some(NumericConstant(e, _))) if s == e =>
-            val end = MfCompiler.nextLabel("of")
+            val end = MosCompiler.nextLabel("of")
             compile(ctx.addLabels(names, Label(end), Label(end)), Assignment(vex, f.start) :: f.body) ++ labelChunk(end)
           case (ForDirection.To | ForDirection.ParallelTo, Some(NumericConstant(s, ssize)), Some(NumericConstant(e, _))) if s > e =>
             Nil
@@ -413,7 +411,7 @@ object StatementCompiler {
             ))
 
           case (ForDirection.DownTo, Some(NumericConstant(s, ssize)), Some(NumericConstant(e, esize))) if s == e =>
-            val end = MfCompiler.nextLabel("of")
+            val end = MosCompiler.nextLabel("of")
             compile(ctx.addLabels(names, Label(end), Label(end)), Assignment(vex, LiteralExpression(s, ssize)) :: f.body) ++ labelChunk(end)
           case (ForDirection.DownTo, Some(NumericConstant(s, ssize)), Some(NumericConstant(e, esize))) if s < e =>
             Nil

src/main/scala/millfork/compiler/mos/PseudoregisterBuiltIns.scala

@@ -1,13 +1,12 @@
-package millfork.compiler
+package millfork.compiler.mos
 
 import millfork.CompilationFlag
-import millfork.assembly.AssemblyLine
+import millfork.assembly.AddrMode._
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.mos._
 import millfork.env._
 import millfork.error.ErrorReporting
 import millfork.node._
-import millfork.assembly.Opcode
-import millfork.assembly.Opcode._
-import millfork.assembly.AddrMode._
 
 /**
   * @author Karol Stasiak
@@ -21,12 +20,12 @@ object PseudoregisterBuiltIns {
       val (variablePart, constPart) = ctx.env.evalVariableAndConstantSubParts(SumExpression(params, decimal = false))
       variablePart match {
         case None =>
-          return ExpressionCompiler.compileConstant(ctx, constPart, RegisterVariable(Register.AX, w))
+          return MosExpressionCompiler.compileConstant(ctx, constPart, RegisterVariable(MosRegister.AX, w))
         case Some(v) =>
-          val typ = ExpressionCompiler.getExpressionType(ctx, v)
+          val typ = MosExpressionCompiler.getExpressionType(ctx, v)
           if (typ.size == 1 && !typ.isSigned) {
-            val bytePart = ExpressionCompiler.compile(ctx, v, Some(b -> RegisterVariable(Register.A, b)), BranchSpec.None)
-            val label = MfCompiler.nextLabel("ah")
+            val bytePart = MosExpressionCompiler.compile(ctx, v, Some(b -> RegisterVariable(MosRegister.A, b)), BranchSpec.None)
+            val label = MosCompiler.nextLabel("ah")
             return bytePart ++ List(
               AssemblyLine.implied(CLC),
               AssemblyLine.immediate(ADC, constPart.loByte),
@@ -47,7 +46,7 @@ object PseudoregisterBuiltIns {
     }
     val reg = ctx.env.get[VariableInMemory]("__reg")
     val head = params.head match {
-      case (false, e) => ExpressionCompiler.compile(ctx, e, Some(ExpressionCompiler.getExpressionType(ctx, e) -> reg), BranchSpec.None)
+      case (false, e) => MosExpressionCompiler.compile(ctx, e, Some(MosExpressionCompiler.getExpressionType(ctx, e) -> reg), BranchSpec.None)
       case (true, e) => ???
     }
     params.tail.foldLeft[List[AssemblyLine]](head){case (code, (sub, param)) => code ++ addToReg(ctx, param, sub, decimal)} ++ List(
@@ -65,7 +64,7 @@ object PseudoregisterBuiltIns {
     val w = ctx.env.get[Type]("word")
     val reg = ctx.env.get[VariableInMemory]("__reg")
     // TODO: smarter on 65816
-    val compileRight = ExpressionCompiler.compile(ctx, r, Some(ExpressionCompiler.getExpressionType(ctx, r) -> reg), BranchSpec.None)
+    val compileRight = MosExpressionCompiler.compile(ctx, r, Some(MosExpressionCompiler.getExpressionType(ctx, r) -> reg), BranchSpec.None)
     val op = if (subtract) SBC else ADC
     val prepareCarry = AssemblyLine.implied(if (subtract) SEC else CLC)
     compileRight match {
@@ -118,7 +117,7 @@ object PseudoregisterBuiltIns {
     val b = ctx.env.get[Type]("byte")
     val w = ctx.env.get[Type]("word")
     val reg = ctx.env.get[VariableInMemory]("__reg")
-    val head = ExpressionCompiler.compile(ctx, params.head, Some(ExpressionCompiler.getExpressionType(ctx, params.head) -> reg), BranchSpec.None)
+    val head = MosExpressionCompiler.compile(ctx, params.head, Some(MosExpressionCompiler.getExpressionType(ctx, params.head) -> reg), BranchSpec.None)
     params.tail.foldLeft[List[AssemblyLine]](head){case (code, param) => code ++ bitOpReg(ctx, param, op)} ++ List(
       AssemblyLine.zeropage(LDA, reg),
       AssemblyLine.zeropage(LDX, reg, 1),
@@ -134,7 +133,7 @@ object PseudoregisterBuiltIns {
     val w = ctx.env.get[Type]("word")
     val reg = ctx.env.get[VariableInMemory]("__reg")
     // TODO: smarter on 65816
-    val compileRight = ExpressionCompiler.compile(ctx, r, Some(ExpressionCompiler.getExpressionType(ctx, r) -> reg), BranchSpec.None)
+    val compileRight = MosExpressionCompiler.compile(ctx, r, Some(MosExpressionCompiler.getExpressionType(ctx, r) -> reg), BranchSpec.None)
     compileRight match {
       case List(
       AssemblyLine(LDA, Immediate, NumericConstant(0, _), _),
@@ -187,7 +186,7 @@ object PseudoregisterBuiltIns {
     val b = ctx.env.get[Type]("byte")
     val w = ctx.env.get[Type]("word")
     val reg = ctx.env.get[VariableInMemory]("__reg")
-    val firstParamCompiled = ExpressionCompiler.compile(ctx, l, Some(ExpressionCompiler.getExpressionType(ctx, l) -> reg), NoBranching)
+    val firstParamCompiled = MosExpressionCompiler.compile(ctx, l, Some(MosExpressionCompiler.getExpressionType(ctx, l) -> reg), NoBranching)
     ctx.env.eval(r) match {
       case Some(NumericConstant(0, _)) =>
         Nil
@@ -204,20 +203,20 @@ object PseudoregisterBuiltIns {
           firstParamCompiled ++ List.fill(v.toInt)(cycle).flatten ++ List(AssemblyLine.zeropage(LDA, reg), AssemblyLine.zeropage(LDX, reg, 1))
         }
       case _ =>
-        val compileCounter = ExpressionCompiler.compile(ctx, r, Some(b -> RegisterVariable(Register.X, b)), NoBranching)
+        val compileCounter = MosExpressionCompiler.compile(ctx, r, Some(b -> RegisterVariable(MosRegister.X, b)), NoBranching)
         val compileCounterAndPrepareFirstParam = compileCounter match {
           case List(AssemblyLine(LDX, _, _, _)) => firstParamCompiled ++ compileCounter
           case List(AssemblyLine(LDY, _, _, _), AssemblyLine(LDX, _, _, _)) => firstParamCompiled ++ compileCounter
           case _ =>
-            ExpressionCompiler.compile(ctx, r, Some(b -> RegisterVariable(Register.A, b)), NoBranching) ++
+            MosExpressionCompiler.compile(ctx, r, Some(b -> RegisterVariable(MosRegister.A, b)), NoBranching) ++
               List(AssemblyLine.implied(PHA)) ++
               firstParamCompiled ++ (
               if (ctx.options.flag(CompilationFlag.EmitCmosOpcodes)) List(AssemblyLine.implied(PLX))
               else List(AssemblyLine.implied(PLA), AssemblyLine.implied(TAX))
               )
         }
-        val labelRepeat = MfCompiler.nextLabel("sr")
-        val labelSkip = MfCompiler.nextLabel("ss")
+        val labelRepeat = MosCompiler.nextLabel("sr")
+        val labelSkip = MosCompiler.nextLabel("ss")
         if (ctx.options.flag(CompilationFlag.EmitNative65816Opcodes)) {
           compileCounterAndPrepareFirstParam ++ List(
             AssemblyLine.relative(BEQ, labelSkip),
@@ -255,8 +254,8 @@ object PseudoregisterBuiltIns {
     val reg = ctx.env.get[VariableInMemory]("__reg")
     val load: List[AssemblyLine] = param1OrRegister match {
       case Some(param1) =>
-        val code1 = ExpressionCompiler.compile(ctx, param1, Some(b -> RegisterVariable(Register.A, b)), BranchSpec.None)
-        val code2 = ExpressionCompiler.compile(ctx, param2, Some(b -> RegisterVariable(Register.A, b)), BranchSpec.None)
+        val code1 = MosExpressionCompiler.compile(ctx, param1, Some(b -> RegisterVariable(MosRegister.A, b)), BranchSpec.None)
+        val code2 = MosExpressionCompiler.compile(ctx, param2, Some(b -> RegisterVariable(MosRegister.A, b)), BranchSpec.None)
         if (!usesRegLo(code2)) {
           code1 ++ List(AssemblyLine.zeropage(STA, reg)) ++ code2 ++ List(AssemblyLine.zeropage(STA, reg, 1))
         } else if (!usesRegLo(code1)) {
@@ -269,7 +268,7 @@ object PseudoregisterBuiltIns {
           )
         }
       case None =>
-        val code2 = ExpressionCompiler.compile(ctx, param2, Some(b -> RegisterVariable(Register.A, b)), BranchSpec.None)
+        val code2 = MosExpressionCompiler.compile(ctx, param2, Some(b -> RegisterVariable(MosRegister.A, b)), BranchSpec.None)
         if (!usesRegLo(code2)) {
           List(AssemblyLine.zeropage(STA, reg)) ++ code2 ++ List(AssemblyLine.zeropage(STA, reg, 1))
         } else if (!usesRegHi(code2)) {

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

@@ -1,7 +1,8 @@
-package millfork.compiler
+package millfork.compiler.mos
 
 import millfork.CompilationFlag
-import millfork.assembly.{AssemblyLine, OpcodeClasses}
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.mos._
 import millfork.env._
 import millfork.error.ErrorReporting
 import millfork.node._
@@ -37,7 +38,7 @@ object ReturnDispatch {
       }
     }
 
-    val indexerType = ExpressionCompiler.getExpressionType(ctx, stmt.indexer)
+    val indexerType = MosExpressionCompiler.getExpressionType(ctx, stmt.indexer)
     if (indexerType.size != 1) {
       ErrorReporting.error("Return dispatch index expression type has to be a byte", stmt.indexer.position)
     }
@@ -120,7 +121,7 @@ object ReturnDispatch {
     }
 
     while (env.parent.isDefined) env = env.parent.get
-    val label = MfCompiler.nextLabel("di")
+    val label = MosCompiler.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(LiteralExpression(0, 1))
@@ -134,11 +135,11 @@ object ReturnDispatch {
     val b = ctx.env.get[Type]("byte")
 
     import millfork.assembly.AddrMode._
-    import millfork.assembly.Opcode._
+    import millfork.assembly.mos.Opcode._
 
     val ctxForStoringParams = ctx.neverCheckArrayBounds
     val copyParams = stmt.params.zipWithIndex.flatMap { case (paramVar, paramIndex) =>
-      val storeParam = ExpressionCompiler.compileByteStorage(ctxForStoringParams, Register.A, paramVar)
+      val storeParam = MosExpressionCompiler.compileByteStorage(ctxForStoringParams, MosRegister.A, paramVar)
       if (storeParam.exists(l => OpcodeClasses.ChangesX(l.opcode)))
         ErrorReporting.error("Invalid/too complex target parameter variable", paramVar.position)
       AssemblyLine.absoluteX(LDA, paramArrays(paramIndex), -paramMins(paramIndex)) :: storeParam
@@ -148,10 +149,10 @@ object ReturnDispatch {
       val jumpTable = InitializedArray(label + "$jt.array", None, (actualMin to actualMax).flatMap(i => List(lobyte0(map(i)._1), hibyte0(map(i)._1))).toList, ctx.function.declaredBank)
       env.registerUnnamedArray(jumpTable)
       if (copyParams.isEmpty) {
-        val loadIndex = ExpressionCompiler.compile(ctx, stmt.indexer, Some(b -> RegisterVariable(Register.A, b)), BranchSpec.None)
+        val loadIndex = MosExpressionCompiler.compile(ctx, stmt.indexer, Some(b -> RegisterVariable(MosRegister.A, b)), BranchSpec.None)
         loadIndex ++ List(AssemblyLine.implied(ASL), AssemblyLine.implied(TAX)) ++ copyParams :+ AssemblyLine(JMP, AbsoluteIndexedX, jumpTable.toAddress - actualMin * 2)
       } else {
-        val loadIndex = ExpressionCompiler.compile(ctx, stmt.indexer, Some(b -> RegisterVariable(Register.X, b)), BranchSpec.None)
+        val loadIndex = MosExpressionCompiler.compile(ctx, stmt.indexer, Some(b -> RegisterVariable(MosRegister.X, b)), BranchSpec.None)
         loadIndex ++ copyParams ++ List(
           AssemblyLine.implied(TXA),
           AssemblyLine.implied(ASL),
@@ -159,7 +160,7 @@ object ReturnDispatch {
           AssemblyLine(JMP, AbsoluteIndexedX, jumpTable.toAddress - actualMin * 2))
       }
     } else {
-      val loadIndex = ExpressionCompiler.compile(ctx, stmt.indexer, Some(b -> RegisterVariable(Register.X, b)), BranchSpec.None)
+      val loadIndex = MosExpressionCompiler.compile(ctx, stmt.indexer, Some(b -> RegisterVariable(MosRegister.X, b)), BranchSpec.None)
       val jumpTableLo = InitializedArray(label + "$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)

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

@@ -3,11 +3,10 @@ package millfork.env
 import java.util.concurrent.atomic.AtomicLong
 
 import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly.{Opcode, OpcodeClasses}
-import millfork.compiler._
+import millfork.assembly.mos.Opcode
 import millfork.error.ErrorReporting
 import millfork.node._
-import millfork.output.{CompiledMemory, MemoryBank, VariableAllocator}
+import millfork.output.{CompiledMemory, VariableAllocator}
 
 import scala.collection.mutable
 
@@ -576,7 +575,7 @@ class Environment(val parent: Option[Environment], val prefix: String) {
             resultType,
             params,
             env,
-            executableStatements ++ (if (needsExtraRTS) List(AssemblyStatement.implied(Opcode.RTS, elidable = true)) else Nil)
+            executableStatements ++ (if (needsExtraRTS) List(MosAssemblyStatement.implied(Opcode.RTS, elidable = true)) else Nil)
           )
           addThing(mangled, stmt.position)
         } else {
@@ -1011,7 +1010,7 @@ class Environment(val parent: Option[Environment], val prefix: String) {
   def nameCheck(nodes: List[_ <:Node]): Unit = nodes.foreach(nameCheck)
 
   def nameCheck(node: Node): Unit = node match {
-    case _:AssemblyStatement => ()
+    case _:MosAssemblyStatement => ()
     case _:DeclarationStatement => ()
     case s:ForStatement =>
       checkName[Variable]("Variable", s.variable, s.position)

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

@@ -1,7 +1,7 @@
 package millfork.env
 
 import millfork.{CompilationFlag, CompilationOptions}
-import millfork.assembly.Opcode
+import millfork.assembly.mos.Opcode
 import millfork.node._
 
 sealed trait Thing {
@@ -122,7 +122,7 @@ sealed trait VariableInMemory extends Variable with ThingInMemory with Indexable
     declaredBank.getOrElse("default")
 }
 
-case class RegisterVariable(register: Register.Value, typ: Type) extends Variable {
+case class RegisterVariable(register: MosRegister.Value, typ: Type) extends Variable {
   def name: String = register.toString
 }
 
@@ -294,7 +294,7 @@ sealed trait ParamPassingConvention {
   def inNonInlinedOnly: Boolean
 }
 
-case class ByRegister(register: Register.Value) extends ParamPassingConvention {
+case class ByRegister(register: MosRegister.Value) extends ParamPassingConvention {
   override def inInlinedOnly = false
 
   override def inNonInlinedOnly = false

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

@@ -1,7 +1,8 @@
 package millfork.node
 
-import millfork.assembly.{AddrMode, Opcode}
-import millfork.env.{Constant, Label, ParamPassingConvention}
+import millfork.assembly.AddrMode
+import millfork.assembly.mos.Opcode
+import millfork.env.{Constant, ParamPassingConvention}
 
 case class Position(filename: String, line: Int, column: Int, cursor: Int)
 
@@ -64,7 +65,7 @@ case class HalfWordExpression(expression: Expression, hiByte: Boolean) extends E
     HalfWordExpression(expression.replaceVariable(variable, actualParam), hiByte)
 }
 
-object Register extends Enumeration {
+object MosRegister extends Enumeration {
   val A, X, Y, AX, AY, YA, XA, XY, YX, AW = Value
 }
 
@@ -211,7 +212,7 @@ case class Assignment(destination: LhsExpression, source: Expression) extends Ex
   override def getAllExpressions: List[Expression] = List(destination, source)
 }
 
-case class AssemblyStatement(opcode: Opcode.Value, addrMode: AddrMode.Value, expression: Expression, elidable: Boolean) extends ExecutableStatement {
+case class MosAssemblyStatement(opcode: Opcode.Value, addrMode: AddrMode.Value, expression: Expression, elidable: Boolean) extends ExecutableStatement {
   override def getAllExpressions: List[Expression] = List(expression)
 }
 
@@ -251,8 +252,8 @@ case class ContinueStatement(label: String) extends ExecutableStatement {
   override def getAllExpressions: List[Expression] = Nil
 }
 
-object AssemblyStatement {
-  def implied(opcode: Opcode.Value, elidable: Boolean) = AssemblyStatement(opcode, AddrMode.Implied, LiteralExpression(0, 1), elidable)
+object MosAssemblyStatement {
+  def implied(opcode: Opcode.Value, elidable: Boolean) = MosAssemblyStatement(opcode, AddrMode.Implied, LiteralExpression(0, 1), elidable)
 
-  def nonexistent(opcode: Opcode.Value) = AssemblyStatement(opcode, AddrMode.DoesNotExist, LiteralExpression(0, 1), elidable = true)
+  def nonexistent(opcode: Opcode.Value) = MosAssemblyStatement(opcode, AddrMode.DoesNotExist, LiteralExpression(0, 1), elidable = true)
 }

src/main/scala/millfork/node/opt/UnusedLocalVariables.scala

@@ -1,7 +1,6 @@
 package millfork.node.opt
 
 import millfork.CompilationOptions
-import millfork.assembly.AssemblyLine
 import millfork.env._
 import millfork.error.ErrorReporting
 import millfork.node._

src/main/scala/millfork/output/AbstractAssembler.scala

@@ -1,12 +1,12 @@
 package millfork.output
 
-import millfork.assembly.opt.{AssemblyOptimization, HudsonOptimizations, JumpFixing, JumpShortening}
-import millfork.assembly.{AddrMode, AssemblyLine, Opcode}
-import millfork.compiler.{CompilationContext, MfCompiler}
+import millfork.assembly._
+import millfork.compiler.AbstractCompiler
 import millfork.env._
 import millfork.error.ErrorReporting
 import millfork.node.{CallGraph, Program}
 import millfork._
+import millfork.compiler.mos.CompilationContext
 
 import scala.collection.mutable
 
@@ -16,7 +16,11 @@ import scala.collection.mutable
 
 case class AssemblerOutput(code: Map[String, Array[Byte]], asm: Array[String], labels: List[(String, Int)])
 
-class Assembler(private val program: Program, private val rootEnv: Environment, private val platform: Platform) {
+abstract class AbstractAssembler[T <: AbstractCode](private val program: Program,
+                                           private val rootEnv: Environment,
+                                           private val platform: Platform,
+                                           private val inliningCalculator: AbstractInliningCalculator[T],
+                                           private val compiler: AbstractCompiler[T]) {
 
   private var env = rootEnv.allThings
   var unoptimizedCodeSize: Int = 0
@@ -165,12 +169,12 @@ class Assembler(private val program: Program, private val rootEnv: Environment,
   private def asDecimal(a: Long, b: Long, f: (Long, Long) => Long): Long =
     storeDecimalValueInNormalRespresentation(f(parseNormalToDecimalValue(a), parseNormalToDecimalValue(b)))
 
-  def assemble(callGraph: CallGraph, optimizations: Seq[AssemblyOptimization], options: CompilationOptions): AssemblerOutput = {
+  def assemble(callGraph: CallGraph, optimizations: Seq[AssemblyOptimization[T]], options: CompilationOptions): AssemblerOutput = {
     val platform = options.platform
 
     val assembly = mutable.ArrayBuffer[String]()
 
-    val inliningResult = InliningCalculator.calculate(
+    val inliningResult = MosInliningCalculator.calculate(
         program,
         options.flags(CompilationFlag.InlineFunctions) || options.flags(CompilationFlag.OptimizeForSonicSpeed),
         if (options.flags(CompilationFlag.OptimizeForSonicSpeed)) 4.0
@@ -183,8 +187,8 @@ class Assembler(private val program: Program, private val rootEnv: Environment,
     val potentiallyInlineable: Map[String, Int] = inliningResult.potentiallyInlineableFunctions
     var nonInlineableFunctions: Set[String] = inliningResult.nonInlineableFunctions
 
-    var inlinedFunctions = Map[String, List[AssemblyLine]]()
-    val compiledFunctions = mutable.Map[String, List[AssemblyLine]]()
+    var inlinedFunctions = Map[String, List[T]]()
+    val compiledFunctions = mutable.Map[String, List[T]]()
     val recommendedCompilationOrder = callGraph.recommendedCompilationOrder
     recommendedCompilationOrder.foreach { f =>
       env.maybeGet[NormalFunction](f).foreach { function =>
@@ -192,7 +196,7 @@ class Assembler(private val program: Program, private val rootEnv: Environment,
         val strippedCodeForInlining = for {
           limit <- potentiallyInlineable.get(f)
           if code.map(_.sizeInBytes).sum <= limit
-          s <- InliningCalculator.codeForInlining(f, nonInlineableFunctions, code)
+          s <- inliningCalculator.codeForInlining(f, nonInlineableFunctions, code)
         } yield s
         strippedCodeForInlining match {
           case Some(c) =>
@@ -418,562 +422,33 @@ class Assembler(private val program: Program, private val rootEnv: Environment,
     AssemblerOutput(code, assembly.toArray, labelMap.toList)
   }
 
-  private def compileFunction(f: NormalFunction, optimizations: Seq[AssemblyOptimization], options: CompilationOptions, inlinedFunctions: Map[String, List[AssemblyLine]]): List[AssemblyLine] = {
+  private def compileFunction(f: NormalFunction, optimizations: Seq[AssemblyOptimization[T]], options: CompilationOptions, inlinedFunctions: Map[String, List[T]]): List[T] = {
     ErrorReporting.debug("Compiling: " + f.name, f.position)
-    val unoptimized =
-      MfCompiler.compile(CompilationContext(env = f.environment, function = f, extraStackOffset = 0, options = options)).flatMap {
-        case AssemblyLine(Opcode.JSR, AddrMode.Absolute | AddrMode.LongAbsolute, p, true) if inlinedFunctions.contains(p.toString) =>
-          val labelPrefix = MfCompiler.nextLabel("ai")
-          inlinedFunctions(p.toString).map{
-            case line@AssemblyLine(_, _, MemoryAddressConstant(Label(label)), _) =>
-              val newLabel = MemoryAddressConstant(Label(labelPrefix + label))
-              line.copy(parameter = newLabel)
-            case l => l
-          }
-        case AssemblyLine(Opcode.JMP, AddrMode.Absolute, p, true) if inlinedFunctions.contains(p.toString) =>
-          val labelPrefix = MfCompiler.nextLabel("ai")
-          inlinedFunctions(p.toString).map{
-            case line@AssemblyLine(_, _, MemoryAddressConstant(Label(label)), _) =>
-              val newLabel = MemoryAddressConstant(Label(labelPrefix + label))
-              line.copy(parameter = newLabel)
-            case l => l
-          } :+ AssemblyLine.implied(Opcode.RTS)
-        case x => List(x)
-      }
+    val unoptimized: List[T] =
+      inliningCalculator.inline(
+        compiler.compile(CompilationContext(env = f.environment, function = f, extraStackOffset = 0, options = options)),
+        inlinedFunctions,
+        compiler)
     unoptimizedCodeSize += unoptimized.map(_.sizeInBytes).sum
     val code = optimizations.foldLeft(unoptimized) { (c, opt) =>
       opt.optimize(f, c, options)
     }
-    if (optimizations.nonEmpty) {
-      val finalCode = if (options.flag(CompilationFlag.EmitHudsonOpcodes)) HudsonOptimizations.removeLoadZero(code) else code
-      JumpShortening(f, JumpShortening(f, JumpFixing(f, finalCode, options), options), options)
-    }
-    else JumpFixing(f, code, options)
+    performFinalOptimizationPass(f, optimizations.nonEmpty, options, code)
   }
 
-  private def outputFunction(bank: String, code: List[AssemblyLine], startFrom: Int, assOut: mutable.ArrayBuffer[String], options: CompilationOptions): Int = {
+  def performFinalOptimizationPass(f: NormalFunction, actuallyOptimize: Boolean, options: CompilationOptions, code: List[T]): List[T]
+
+  private def outputFunction(bank: String, code: List[T], startFrom: Int, assOut: mutable.ArrayBuffer[String], options: CompilationOptions): Int = {
     var index = startFrom
     assOut.append("* = $" + startFrom.toHexString)
-    import millfork.assembly.AddrMode._
-    import millfork.assembly.Opcode._
     for (instr <- code) {
       if (instr.isPrintable) {
         assOut.append(instr.toString)
       }
-      instr match {
-        case AssemblyLine(BYTE, RawByte, c, _) =>
-          writeByte(bank, index, c)
-          index += 1
-        case AssemblyLine(BYTE, _, _, _) => ???
-        case AssemblyLine(_, RawByte, _, _) => ???
-        case AssemblyLine(LABEL, _, MemoryAddressConstant(Label(labelName)), _) =>
-          labelMap(labelName) = index
-        case AssemblyLine(_, DoesNotExist, _, _) =>
-          ()
-        case AssemblyLine(op, Implied, _, _) =>
-          writeByte(bank, index, Assembler.opcodeFor(op, Implied, options))
-          index += 1
-        case AssemblyLine(op, Relative, param, _) =>
-          writeByte(bank, index, Assembler.opcodeFor(op, Relative, options))
-          writeByte(bank, index + 1, AssertByte(param - (index + 2)))
-          index += 2
-        case AssemblyLine(op, am@(Immediate | ZeroPage | ZeroPageX | ZeroPageY | IndexedY | IndexedX | IndexedZ | LongIndexedY | LongIndexedZ | Stack), param, _) =>
-          writeByte(bank, index, Assembler.opcodeFor(op, am, options))
-          writeByte(bank, index + 1, param)
-          index += 2
-        case AssemblyLine(op, am@(WordImmediate | Absolute | AbsoluteY | AbsoluteX | Indirect | AbsoluteIndexedX), param, _) =>
-          writeByte(bank, index, Assembler.opcodeFor(op, am, options))
-          writeWord(bank, index + 1, param)
-          index += 3
-        case AssemblyLine(op, am@(LongAbsolute | LongAbsoluteX | LongIndirect), param, _) =>
-          writeByte(bank, index, Assembler.opcodeFor(op, am, options))
-          writeWord(bank, index + 1, param)
-          writeByte(bank, index + 3, extractBank(param, options))
-          index += 4
-      }
+      index = emitInstruction(bank, options, index, instr)
     }
     index
   }
-}
 
-object Assembler {
-  val opcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
-  val illegalOpcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
-  val cmosOpcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
-  val cmosNopOpcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
-  val ce02Opcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
-  val hudsonOpcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
-  val emulation65816Opcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
-  val native65816Opcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
-
-  def opcodeFor(opcode: Opcode.Value, addrMode: AddrMode.Value, options: CompilationOptions): Byte = {
-    val key = opcode -> addrMode
-    opcodes.get(key).foreach(return _)
-    if (options.flag(CompilationFlag.EmitIllegals)) illegalOpcodes.get(key).foreach(return _)
-    if (options.flag(CompilationFlag.EmitCmosOpcodes)) cmosOpcodes.get(key).foreach(return _)
-    if (options.flag(CompilationFlag.EmitCmosNopOpcodes)) cmosNopOpcodes.get(key).foreach(return _)
-    if (options.flag(CompilationFlag.Emit65CE02Opcodes)) ce02Opcodes.get(key).foreach(return _)
-    if (options.flag(CompilationFlag.EmitHudsonOpcodes))  hudsonOpcodes.get(key).foreach(return _)
-    if (options.flag(CompilationFlag.EmitEmulation65816Opcodes)) emulation65816Opcodes.get(key).foreach(return _)
-    if (options.flag(CompilationFlag.EmitNative65816Opcodes)) native65816Opcodes.get(key).foreach(return _)
-    ErrorReporting.fatal("Cannot assemble an unknown opcode " + key)
-  }
-
-  private def op(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
-    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
-    opcodes(op -> am) = x.toByte
-    if (am == AddrMode.Relative) opcodes(op -> AddrMode.Immediate) = x.toByte
-  }
-
-  private def cm(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
-    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
-    cmosOpcodes(op -> am) = x.toByte
-  }
-
-  private def cn(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
-    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
-    cmosNopOpcodes(op -> am) = x.toByte
-  }
-
-  private def il(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
-    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
-    illegalOpcodes(op -> am) = x.toByte
-  }
-
-  private def hu(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
-    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
-    hudsonOpcodes(op -> am) = x.toByte
-  }
-
-  private def ce(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
-    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
-    ce02Opcodes(op -> am) = x.toByte
-  }
-
-  private def em(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
-    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
-    emulation65816Opcodes(op -> am) = x.toByte
-  }
-
-  private def na(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
-    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
-    native65816Opcodes(op -> am) = x.toByte
-  }
-
-  def getStandardLegalOpcodes: Set[Int] = opcodes.values.map(_ & 0xff).toSet
-
-  import AddrMode._
-  import Opcode._
-
-  op(ADC, Immediate, 0x69)
-  op(ADC, ZeroPage, 0x65)
-  op(ADC, ZeroPageX, 0x75)
-  op(ADC, Absolute, 0x6D)
-  op(ADC, AbsoluteX, 0x7D)
-  op(ADC, AbsoluteY, 0x79)
-  op(ADC, IndexedX, 0x61)
-  op(ADC, IndexedY, 0x71)
-
-  op(AND, Immediate, 0x29)
-  op(AND, ZeroPage, 0x25)
-  op(AND, ZeroPageX, 0x35)
-  op(AND, Absolute, 0x2D)
-  op(AND, AbsoluteX, 0x3D)
-  op(AND, AbsoluteY, 0x39)
-  op(AND, IndexedX, 0x21)
-  op(AND, IndexedY, 0x31)
-
-  op(ASL, Implied, 0x0A)
-  op(ASL, ZeroPage, 0x06)
-  op(ASL, ZeroPageX, 0x16)
-  op(ASL, Absolute, 0x0E)
-  op(ASL, AbsoluteX, 0x1E)
-
-  op(BIT, ZeroPage, 0x24)
-  op(BIT, Absolute, 0x2C)
-
-  op(BPL, Relative, 0x10)
-  op(BMI, Relative, 0x30)
-  op(BVC, Relative, 0x50)
-  op(BVS, Relative, 0x70)
-  op(BCC, Relative, 0x90)
-  op(BCS, Relative, 0xB0)
-  op(BNE, Relative, 0xD0)
-  op(BEQ, Relative, 0xF0)
-
-  op(BRK, Implied, 0)
-
-  op(CMP, Immediate, 0xC9)
-  op(CMP, ZeroPage, 0xC5)
-  op(CMP, ZeroPageX, 0xD5)
-  op(CMP, Absolute, 0xCD)
-  op(CMP, AbsoluteX, 0xDD)
-  op(CMP, AbsoluteY, 0xD9)
-  op(CMP, IndexedX, 0xC1)
-  op(CMP, IndexedY, 0xD1)
-
-  op(CPX, Immediate, 0xE0)
-  op(CPX, ZeroPage, 0xE4)
-  op(CPX, Absolute, 0xEC)
-
-  op(CPY, Immediate, 0xC0)
-  op(CPY, ZeroPage, 0xC4)
-  op(CPY, Absolute, 0xCC)
-
-  op(DEC, ZeroPage, 0xC6)
-  op(DEC, ZeroPageX, 0xD6)
-  op(DEC, Absolute, 0xCE)
-  op(DEC, AbsoluteX, 0xDE)
-
-  op(EOR, Immediate, 0x49)
-  op(EOR, ZeroPage, 0x45)
-  op(EOR, ZeroPageX, 0x55)
-  op(EOR, Absolute, 0x4D)
-  op(EOR, AbsoluteX, 0x5D)
-  op(EOR, AbsoluteY, 0x59)
-  op(EOR, IndexedX, 0x41)
-  op(EOR, IndexedY, 0x51)
-
-  op(INC, ZeroPage, 0xE6)
-  op(INC, ZeroPageX, 0xF6)
-  op(INC, Absolute, 0xEE)
-  op(INC, AbsoluteX, 0xFE)
-
-  op(CLC, Implied, 0x18)
-  op(SEC, Implied, 0x38)
-  op(CLI, Implied, 0x58)
-  op(SEI, Implied, 0x78)
-  op(CLV, Implied, 0xB8)
-  op(CLD, Implied, 0xD8)
-  op(SED, Implied, 0xF8)
-
-  op(JMP, Absolute, 0x4C)
-  op(JMP, Indirect, 0x6C)
-
-  op(JSR, Absolute, 0x20)
-
-  op(LDA, Immediate, 0xA9)
-  op(LDA, ZeroPage, 0xA5)
-  op(LDA, ZeroPageX, 0xB5)
-  op(LDA, Absolute, 0xAD)
-  op(LDA, AbsoluteX, 0xBD)
-  op(LDA, AbsoluteY, 0xB9)
-  op(LDA, IndexedX, 0xA1)
-  op(LDA, IndexedY, 0xB1)
-
-  op(LDX, Immediate, 0xA2)
-  op(LDX, ZeroPage, 0xA6)
-  op(LDX, ZeroPageY, 0xB6)
-  op(LDX, Absolute, 0xAE)
-  op(LDX, AbsoluteY, 0xBE)
-
-  op(LDY, Immediate, 0xA0)
-  op(LDY, ZeroPage, 0xA4)
-  op(LDY, ZeroPageX, 0xB4)
-  op(LDY, Absolute, 0xAC)
-  op(LDY, AbsoluteX, 0xBC)
-
-  op(LSR, Implied, 0x4A)
-  op(LSR, ZeroPage, 0x46)
-  op(LSR, ZeroPageX, 0x56)
-  op(LSR, Absolute, 0x4E)
-  op(LSR, AbsoluteX, 0x5E)
-
-  op(NOP, Implied, 0xEA)
-
-  op(ORA, Immediate, 0x09)
-  op(ORA, ZeroPage, 0x05)
-  op(ORA, ZeroPageX, 0x15)
-  op(ORA, Absolute, 0x0D)
-  op(ORA, AbsoluteX, 0x1D)
-  op(ORA, AbsoluteY, 0x19)
-  op(ORA, IndexedX, 0x01)
-  op(ORA, IndexedY, 0x11)
-
-  op(TAX, Implied, 0xAA)
-  op(TXA, Implied, 0x8A)
-  op(DEX, Implied, 0xCA)
-  op(INX, Implied, 0xE8)
-  op(TAY, Implied, 0xA8)
-  op(TYA, Implied, 0x98)
-  op(DEY, Implied, 0x88)
-  op(INY, Implied, 0xC8)
-
-  op(ROL, Implied, 0x2A)
-  op(ROL, ZeroPage, 0x26)
-  op(ROL, ZeroPageX, 0x36)
-  op(ROL, Absolute, 0x2E)
-  op(ROL, AbsoluteX, 0x3E)
-
-  op(ROR, Implied, 0x6A)
-  op(ROR, ZeroPage, 0x66)
-  op(ROR, ZeroPageX, 0x76)
-  op(ROR, Absolute, 0x6E)
-  op(ROR, AbsoluteX, 0x7E)
-
-  op(RTI, Implied, 0x40)
-  op(RTS, Implied, 0x60)
-
-  op(SBC, Immediate, 0xE9)
-  op(SBC, ZeroPage, 0xE5)
-  op(SBC, ZeroPageX, 0xF5)
-  op(SBC, Absolute, 0xED)
-  op(SBC, AbsoluteX, 0xFD)
-  op(SBC, AbsoluteY, 0xF9)
-  op(SBC, IndexedX, 0xE1)
-  op(SBC, IndexedY, 0xF1)
-
-  op(STA, ZeroPage, 0x85)
-  op(STA, ZeroPageX, 0x95)
-  op(STA, Absolute, 0x8D)
-  op(STA, AbsoluteX, 0x9D)
-  op(STA, AbsoluteY, 0x99)
-  op(STA, IndexedX, 0x81)
-  op(STA, IndexedY, 0x91)
-
-  op(TXS, Implied, 0x9A)
-  op(TSX, Implied, 0xBA)
-  op(PHA, Implied, 0x48)
-  op(PLA, Implied, 0x68)
-  op(PHP, Implied, 0x08)
-  op(PLP, Implied, 0x28)
-
-  op(STX, ZeroPage, 0x86)
-  op(STX, ZeroPageY, 0x96)
-  op(STX, Absolute, 0x8E)
-
-  op(STY, ZeroPage, 0x84)
-  op(STY, ZeroPageX, 0x94)
-  op(STY, Absolute, 0x8C)
-
-  il(LAX, ZeroPage, 0xA7)
-  il(LAX, ZeroPageY, 0xB7)
-  il(LAX, Absolute, 0xAF)
-  il(LAX, AbsoluteY, 0xBF)
-  il(LAX, IndexedX, 0xA3)
-  il(LAX, IndexedY, 0xB3)
-
-  il(SAX, ZeroPage, 0x87)
-  il(SAX, ZeroPageY, 0x97)
-  il(SAX, Absolute, 0x8F)
-  il(TAS, AbsoluteY, 0x9B)
-  il(AHX, AbsoluteY, 0x9F)
-  il(SAX, IndexedX, 0x83)
-  il(AHX, IndexedY, 0x93)
-  il(SHY, AbsoluteX, 0x9C)
-
-  il(ANC, Immediate, 0x0B)
-  il(ALR, Immediate, 0x4B)
-  il(ARR, Immediate, 0x6B)
-  il(XAA, Immediate, 0x8B)
-  il(LXA, Immediate, 0xAB)
-  il(SBX, Immediate, 0xCB)
-
-  il(SLO, ZeroPage, 0x07)
-  il(SLO, ZeroPageX, 0x17)
-  il(SLO, IndexedX, 0x03)
-  il(SLO, IndexedY, 0x13)
-  il(SLO, Absolute, 0x0F)
-  il(SLO, AbsoluteX, 0x1F)
-  il(SLO, AbsoluteY, 0x1B)
-
-  il(RLA, ZeroPage, 0x27)
-  il(RLA, ZeroPageX, 0x37)
-  il(RLA, IndexedX, 0x23)
-  il(RLA, IndexedY, 0x33)
-  il(RLA, Absolute, 0x2F)
-  il(RLA, AbsoluteX, 0x3F)
-  il(RLA, AbsoluteY, 0x3B)
-
-  il(SRE, ZeroPage, 0x47)
-  il(SRE, ZeroPageX, 0x57)
-  il(SRE, IndexedX, 0x43)
-  il(SRE, IndexedY, 0x53)
-  il(SRE, Absolute, 0x4F)
-  il(SRE, AbsoluteX, 0x5F)
-  il(SRE, AbsoluteY, 0x5B)
-
-  il(RRA, ZeroPage, 0x67)
-  il(RRA, ZeroPageX, 0x77)
-  il(RRA, IndexedX, 0x63)
-  il(RRA, IndexedY, 0x73)
-  il(RRA, Absolute, 0x6F)
-  il(RRA, AbsoluteX, 0x7F)
-  il(RRA, AbsoluteY, 0x7B)
-
-  il(DCP, ZeroPage, 0xC7)
-  il(DCP, ZeroPageX, 0xD7)
-  il(DCP, IndexedX, 0xC3)
-  il(DCP, IndexedY, 0xD3)
-  il(DCP, Absolute, 0xCF)
-  il(DCP, AbsoluteX, 0xDF)
-  il(DCP, AbsoluteY, 0xDB)
-
-  il(ISC, ZeroPage, 0xE7)
-  il(ISC, ZeroPageX, 0xF7)
-  il(ISC, IndexedX, 0xE3)
-  il(ISC, IndexedY, 0xF3)
-  il(ISC, Absolute, 0xEF)
-  il(ISC, AbsoluteX, 0xFF)
-  il(ISC, AbsoluteY, 0xFB)
-
-  il(NOP, Immediate, 0x80)
-  il(NOP, ZeroPage, 0x44)
-  il(NOP, ZeroPageX, 0x54)
-  il(NOP, Absolute, 0x5C)
-  il(NOP, AbsoluteX, 0x1C)
-
-  cn(NOP, Immediate, 0x02)
-  cn(NOP, ZeroPage, 0x44)
-  cn(NOP, ZeroPageX, 0x54)
-  cn(NOP, Absolute, 0x5C)
-
-  cm(STZ, ZeroPage, 0x64)
-  cm(STZ, ZeroPageX, 0x74)
-  cm(STZ, Absolute, 0x9C)
-  cm(STZ, AbsoluteX, 0x9E)
-
-  cm(PHX, Implied, 0xDA)
-  cm(PHY, Implied, 0x5A)
-  cm(PLX, Implied, 0xFA)
-  cm(PLY, Implied, 0x7A)
-
-  cm(ORA, IndexedZ, 0x12)
-  cm(AND, IndexedZ, 0x32)
-  cm(EOR, IndexedZ, 0x52)
-  cm(ADC, IndexedZ, 0x72)
-  cm(STA, IndexedZ, 0x92)
-  cm(LDA, IndexedZ, 0xB2)
-  cm(CMP, IndexedZ, 0xD2)
-  cm(SBC, IndexedZ, 0xF2)
-
-  cm(TSB, ZeroPage, 0x04)
-  cm(TSB, Absolute, 0x0C)
-  cm(TRB, ZeroPage, 0x14)
-  cm(TRB, Absolute, 0x1C)
-
-  cm(BRA, Relative, 0x80)
-  cm(BIT, ZeroPageX, 0x34)
-  cm(BIT, AbsoluteX, 0x3C)
-  cm(INC, Implied, 0x1A)
-  cm(DEC, Implied, 0x3A)
-  cm(JMP, AbsoluteIndexedX, 0x7C)
-  cm(WAI, Implied, 0xCB)
-  cm(STP, Implied, 0xDB)
-
-  ce(CPZ, Immediate, 0xC2)
-  ce(CPZ, ZeroPage, 0xD4)
-  ce(CPZ, Absolute, 0xDC)
-  ce(DEZ, Implied, 0x3B)
-  ce(INZ, Implied,0x1B )
-  ce(DEC_W, ZeroPage, 0xC3)
-  ce(INC_W, ZeroPage, 0xE3)
-  ce(ASL_W, Absolute, 0xCB)
-  // TODO: or is it ROL_W?
-  ce(ROR_W, Absolute, 0xEB)
-  ce(ASR, Implied, 0x43)
-  ce(ASR, ZeroPage, 0x44)
-  ce(ASR, ZeroPageX, 0x54)
-  ce(LDZ, Immediate, 0xA3)
-  ce(LDZ, Absolute, 0xAB)
-  ce(LDZ, AbsoluteX, 0xBB)
-  ce(TAB, Implied, 0x5B)
-  ce(TBA, Implied, 0x7B)
-  ce(TAZ, Implied, 0x4B)
-  ce(TZA, Implied, 0x6B)
-  ce(TSY, Implied, 0x0B)
-  ce(TYS, Implied, 0x2B)
-  ce(PHW, WordImmediate, 0xF4)
-  ce(PHW, Absolute, 0xFC)
-  ce(PHZ, Implied, 0xDB)
-  ce(PLZ, Implied, 0xFB)
-//  ce(CLE, Implied, )
-//  ce(SEE, Implied, )
-//  ce(BSR, , )
-
-  hu(CLY, Implied, 0xC2)
-  hu(CLX, Implied, 0x82)
-  hu(CLA, Implied, 0x62)
-  hu(CSH, Implied, 0xD4)
-  hu(CSL, Implied, 0x54)
-  hu(HuSAX, Implied, 0x22)
-  hu(SAY, Implied, 0x42)
-  hu(SXY, Implied, 0x02)
-  hu(TAM, Immediate, 0x53)
-  hu(TMA, Immediate, 0x43)
-
-  em(ORA, Stack, 0x03)
-  em(ORA, IndexedSY, 0x13)
-  na(ORA, LongIndexedZ, 0x07)
-  na(ORA, LongIndexedY, 0x17)
-  na(ORA, LongAbsolute, 0x0F)
-  na(ORA, LongAbsoluteX, 0x1F)
-  em(AND, Stack, 0x23)
-  em(AND, IndexedSY, 0x33)
-  na(AND, LongIndexedZ, 0x27)
-  na(AND, LongIndexedY, 0x37)
-  na(AND, LongAbsolute, 0x2F)
-  na(AND, LongAbsoluteX, 0x3F)
-  em(EOR, Stack, 0x43)
-  em(EOR, IndexedSY, 0x53)
-  na(EOR, LongIndexedZ, 0x47)
-  na(EOR, LongIndexedY, 0x57)
-  na(EOR, LongAbsolute, 0x4F)
-  na(EOR, LongAbsoluteX, 0x5F)
-  em(ADC, Stack, 0x63)
-  em(ADC, IndexedSY, 0x73)
-  na(ADC, LongIndexedZ, 0x67)
-  na(ADC, LongIndexedY, 0x77)
-  na(ADC, LongAbsolute, 0x6F)
-  na(ADC, LongAbsoluteX, 0x7F)
-  em(STA, Stack, 0x83)
-  em(STA, IndexedSY, 0x93)
-  na(STA, LongIndexedZ, 0x87)
-  na(STA, LongIndexedY, 0x97)
-  na(STA, LongAbsolute, 0x8F)
-  na(STA, LongAbsoluteX, 0x9F)
-  em(LDA, Stack, 0xA3)
-  em(LDA, IndexedSY, 0xB3)
-  na(LDA, LongIndexedZ, 0xA7)
-  na(LDA, LongIndexedY, 0xB7)
-  na(LDA, LongAbsolute, 0xAF)
-  na(LDA, LongAbsoluteX, 0xBF)
-  em(CMP, Stack, 0xA3)
-  em(CMP, IndexedSY, 0xB3)
-  na(CMP, LongIndexedZ, 0xA7)
-  na(CMP, LongIndexedY, 0xB7)
-  na(CMP, LongAbsolute, 0xAF)
-  na(CMP, LongAbsoluteX, 0xBF)
-
-  em(COP, Immediate, 0x02)
-  em(XBA, Implied, 0xEB)
-  em(TXY, Implied, 0x9B)
-  em(TYX, Implied, 0xBB)
-
-
-  na(RTL, Implied, 0x6B)
-  na(JMP, LongAbsolute, 0x5C)
-  na(JMP, LongIndirect, 0x7C)
-  na(BRL, LongRelative, 0x82)
-
-  em(PHD, Implied, 0x0B)
-  em(PLD, Implied, 0x2B)
-  em(PHB, Implied, 0x8B)
-  em(PLB, Implied, 0xAB)
-  em(PHK, Implied, 0x4B)
-
-  na(REP, Immediate, 0xC2)
-  na(SEP, Immediate, 0xE2)
-
-  na(XCE, Implied, 0xFB)
-  na(TCD, Implied, 0x5B)
-  na(TDC, Implied, 0x7B)
-  na(TSC, Implied, 0x3B)
-  na(TCS, Implied, 0x1B)
-
-  for {
-    ((narrow, am), code) <- emulation65816Opcodes ++ opcodes ++ cmosOpcodes ++ native65816Opcodes
-    wide <- Opcode.widen(narrow)
-  } na(wide, if (am == Immediate) WordImmediate else am, code & 0xff)
-
-}
+  def emitInstruction(bank: String, options: CompilationOptions, index: Int, instr: T): Int
+}

src/main/scala/millfork/output/AbstractInliningCalculator.scala

@@ -0,0 +1,12 @@
+package millfork.output
+
+import millfork.assembly.AbstractCode
+import millfork.compiler.AbstractCompiler
+
+/**
+  * @author Karol Stasiak
+  */
+abstract class AbstractInliningCalculator[T <: AbstractCode] {
+  def codeForInlining(fname: String, functionsAlreadyKnownToBeNonInlineable: Set[String], code: List[T]): Option[List[T]]
+  def inline(code: List[T], inlinedFunctions: Map[String, List[T]], compiler: AbstractCompiler[T]): List[T]
+}

src/main/scala/millfork/output/MosAssembler.scala

@@ -0,0 +1,549 @@
+package millfork.output
+
+import millfork.assembly.mos.opt.{HudsonOptimizations, JumpFixing, JumpShortening}
+import millfork.assembly._
+import millfork.env._
+import millfork.error.ErrorReporting
+import millfork.node.Program
+import millfork._
+import millfork.assembly.mos.{AssemblyLine, Opcode}
+import millfork.compiler.mos.MosCompiler
+
+import scala.collection.mutable
+
+/**
+  * @author Karol Stasiak
+  */
+class MosAssembler(program: Program,
+                   rootEnv: Environment,
+                   platform: Platform) extends AbstractAssembler[AssemblyLine](program, rootEnv, platform, MosInliningCalculator, MosCompiler) {
+
+
+  override def performFinalOptimizationPass(f: NormalFunction, actuallyOptimize: Boolean, options: CompilationOptions, code: List[AssemblyLine]):List[AssemblyLine] = {
+    if (actuallyOptimize) {
+      val finalCode = if (options.flag(CompilationFlag.EmitHudsonOpcodes)) HudsonOptimizations.removeLoadZero(code) else code
+      JumpShortening(f, JumpShortening(f, JumpFixing(f, finalCode, options), options), options)
+    }
+    else JumpFixing(f, code, options)
+  }
+
+  override def emitInstruction(bank: String, options: CompilationOptions, index: Int, instr: AssemblyLine): Int = {
+    import millfork.assembly.AddrMode._
+    import millfork.assembly.mos.Opcode._
+    instr match {
+      case AssemblyLine(BYTE, RawByte, c, _) =>
+        writeByte(bank, index, c)
+        index + 1
+      case AssemblyLine(BYTE, _, _, _) => ???
+      case AssemblyLine(_, RawByte, _, _) => ???
+      case AssemblyLine(LABEL, _, MemoryAddressConstant(Label(labelName)), _) =>
+        labelMap(labelName) = index
+        index
+      case AssemblyLine(_, DoesNotExist, _, _) =>
+        index
+      case AssemblyLine(op, Implied, _, _) =>
+        writeByte(bank, index, MosAssembler.opcodeFor(op, Implied, options))
+        index + 1
+      case AssemblyLine(op, Relative, param, _) =>
+        writeByte(bank, index, MosAssembler.opcodeFor(op, Relative, options))
+        writeByte(bank, index + 1, AssertByte(param - (index + 2)))
+        index + 2
+      case AssemblyLine(op, am@(Immediate | ZeroPage | ZeroPageX | ZeroPageY | IndexedY | IndexedX | IndexedZ | LongIndexedY | LongIndexedZ | Stack), param, _) =>
+        writeByte(bank, index, MosAssembler.opcodeFor(op, am, options))
+        writeByte(bank, index + 1, param)
+        index + 2
+      case AssemblyLine(op, am@(WordImmediate | Absolute | AbsoluteY | AbsoluteX | Indirect | AbsoluteIndexedX), param, _) =>
+        writeByte(bank, index, MosAssembler.opcodeFor(op, am, options))
+        writeWord(bank, index + 1, param)
+        index + 3
+      case AssemblyLine(op, am@(LongAbsolute | LongAbsoluteX | LongIndirect), param, _) =>
+        writeByte(bank, index, MosAssembler.opcodeFor(op, am, options))
+        writeWord(bank, index + 1, param)
+        writeByte(bank, index + 3, extractBank(param, options))
+        index + 4
+    }
+  }
+}
+
+
+object MosAssembler {
+  val opcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
+  val illegalOpcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
+  val cmosOpcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
+  val cmosNopOpcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
+  val ce02Opcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
+  val hudsonOpcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
+  val emulation65816Opcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
+  val native65816Opcodes = mutable.Map[(Opcode.Value, AddrMode.Value), Byte]()
+
+  def opcodeFor(opcode: Opcode.Value, addrMode: AddrMode.Value, options: CompilationOptions): Byte = {
+    val key = opcode -> addrMode
+    opcodes.get(key).foreach(return _)
+    if (options.flag(CompilationFlag.EmitIllegals)) illegalOpcodes.get(key).foreach(return _)
+    if (options.flag(CompilationFlag.EmitCmosOpcodes)) cmosOpcodes.get(key).foreach(return _)
+    if (options.flag(CompilationFlag.EmitCmosNopOpcodes)) cmosNopOpcodes.get(key).foreach(return _)
+    if (options.flag(CompilationFlag.Emit65CE02Opcodes)) ce02Opcodes.get(key).foreach(return _)
+    if (options.flag(CompilationFlag.EmitHudsonOpcodes))  hudsonOpcodes.get(key).foreach(return _)
+    if (options.flag(CompilationFlag.EmitEmulation65816Opcodes)) emulation65816Opcodes.get(key).foreach(return _)
+    if (options.flag(CompilationFlag.EmitNative65816Opcodes)) native65816Opcodes.get(key).foreach(return _)
+    ErrorReporting.fatal("Cannot assemble an unknown opcode " + key)
+  }
+
+  private def op(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
+    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
+    opcodes(op -> am) = x.toByte
+    if (am == AddrMode.Relative) opcodes(op -> AddrMode.Immediate) = x.toByte
+  }
+
+  private def cm(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
+    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
+    cmosOpcodes(op -> am) = x.toByte
+  }
+
+  private def cn(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
+    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
+    cmosNopOpcodes(op -> am) = x.toByte
+  }
+
+  private def il(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
+    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
+    illegalOpcodes(op -> am) = x.toByte
+  }
+
+  private def hu(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
+    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
+    hudsonOpcodes(op -> am) = x.toByte
+  }
+
+  private def ce(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
+    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
+    ce02Opcodes(op -> am) = x.toByte
+  }
+
+  private def em(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
+    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
+    emulation65816Opcodes(op -> am) = x.toByte
+  }
+
+  private def na(op: Opcode.Value, am: AddrMode.Value, x: Int): Unit = {
+    if (x < 0 || x > 0xff) ErrorReporting.fatal("Invalid code for" + (op -> am))
+    native65816Opcodes(op -> am) = x.toByte
+  }
+
+  def getStandardLegalOpcodes: Set[Int] = opcodes.values.map(_ & 0xff).toSet
+
+  import AddrMode._
+  import Opcode._
+
+  op(ADC, Immediate, 0x69)
+  op(ADC, ZeroPage, 0x65)
+  op(ADC, ZeroPageX, 0x75)
+  op(ADC, Absolute, 0x6D)
+  op(ADC, AbsoluteX, 0x7D)
+  op(ADC, AbsoluteY, 0x79)
+  op(ADC, IndexedX, 0x61)
+  op(ADC, IndexedY, 0x71)
+
+  op(AND, Immediate, 0x29)
+  op(AND, ZeroPage, 0x25)
+  op(AND, ZeroPageX, 0x35)
+  op(AND, Absolute, 0x2D)
+  op(AND, AbsoluteX, 0x3D)
+  op(AND, AbsoluteY, 0x39)
+  op(AND, IndexedX, 0x21)
+  op(AND, IndexedY, 0x31)
+
+  op(ASL, Implied, 0x0A)
+  op(ASL, ZeroPage, 0x06)
+  op(ASL, ZeroPageX, 0x16)
+  op(ASL, Absolute, 0x0E)
+  op(ASL, AbsoluteX, 0x1E)
+
+  op(BIT, ZeroPage, 0x24)
+  op(BIT, Absolute, 0x2C)
+
+  op(BPL, Relative, 0x10)
+  op(BMI, Relative, 0x30)
+  op(BVC, Relative, 0x50)
+  op(BVS, Relative, 0x70)
+  op(BCC, Relative, 0x90)
+  op(BCS, Relative, 0xB0)
+  op(BNE, Relative, 0xD0)
+  op(BEQ, Relative, 0xF0)
+
+  op(BRK, Implied, 0)
+
+  op(CMP, Immediate, 0xC9)
+  op(CMP, ZeroPage, 0xC5)
+  op(CMP, ZeroPageX, 0xD5)
+  op(CMP, Absolute, 0xCD)
+  op(CMP, AbsoluteX, 0xDD)
+  op(CMP, AbsoluteY, 0xD9)
+  op(CMP, IndexedX, 0xC1)
+  op(CMP, IndexedY, 0xD1)
+
+  op(CPX, Immediate, 0xE0)
+  op(CPX, ZeroPage, 0xE4)
+  op(CPX, Absolute, 0xEC)
+
+  op(CPY, Immediate, 0xC0)
+  op(CPY, ZeroPage, 0xC4)
+  op(CPY, Absolute, 0xCC)
+
+  op(DEC, ZeroPage, 0xC6)
+  op(DEC, ZeroPageX, 0xD6)
+  op(DEC, Absolute, 0xCE)
+  op(DEC, AbsoluteX, 0xDE)
+
+  op(EOR, Immediate, 0x49)
+  op(EOR, ZeroPage, 0x45)
+  op(EOR, ZeroPageX, 0x55)
+  op(EOR, Absolute, 0x4D)
+  op(EOR, AbsoluteX, 0x5D)
+  op(EOR, AbsoluteY, 0x59)
+  op(EOR, IndexedX, 0x41)
+  op(EOR, IndexedY, 0x51)
+
+  op(INC, ZeroPage, 0xE6)
+  op(INC, ZeroPageX, 0xF6)
+  op(INC, Absolute, 0xEE)
+  op(INC, AbsoluteX, 0xFE)
+
+  op(CLC, Implied, 0x18)
+  op(SEC, Implied, 0x38)
+  op(CLI, Implied, 0x58)
+  op(SEI, Implied, 0x78)
+  op(CLV, Implied, 0xB8)
+  op(CLD, Implied, 0xD8)
+  op(SED, Implied, 0xF8)
+
+  op(JMP, Absolute, 0x4C)
+  op(JMP, Indirect, 0x6C)
+
+  op(JSR, Absolute, 0x20)
+
+  op(LDA, Immediate, 0xA9)
+  op(LDA, ZeroPage, 0xA5)
+  op(LDA, ZeroPageX, 0xB5)
+  op(LDA, Absolute, 0xAD)
+  op(LDA, AbsoluteX, 0xBD)
+  op(LDA, AbsoluteY, 0xB9)
+  op(LDA, IndexedX, 0xA1)
+  op(LDA, IndexedY, 0xB1)
+
+  op(LDX, Immediate, 0xA2)
+  op(LDX, ZeroPage, 0xA6)
+  op(LDX, ZeroPageY, 0xB6)
+  op(LDX, Absolute, 0xAE)
+  op(LDX, AbsoluteY, 0xBE)
+
+  op(LDY, Immediate, 0xA0)
+  op(LDY, ZeroPage, 0xA4)
+  op(LDY, ZeroPageX, 0xB4)
+  op(LDY, Absolute, 0xAC)
+  op(LDY, AbsoluteX, 0xBC)
+
+  op(LSR, Implied, 0x4A)
+  op(LSR, ZeroPage, 0x46)
+  op(LSR, ZeroPageX, 0x56)
+  op(LSR, Absolute, 0x4E)
+  op(LSR, AbsoluteX, 0x5E)
+
+  op(NOP, Implied, 0xEA)
+
+  op(ORA, Immediate, 0x09)
+  op(ORA, ZeroPage, 0x05)
+  op(ORA, ZeroPageX, 0x15)
+  op(ORA, Absolute, 0x0D)
+  op(ORA, AbsoluteX, 0x1D)
+  op(ORA, AbsoluteY, 0x19)
+  op(ORA, IndexedX, 0x01)
+  op(ORA, IndexedY, 0x11)
+
+  op(TAX, Implied, 0xAA)
+  op(TXA, Implied, 0x8A)
+  op(DEX, Implied, 0xCA)
+  op(INX, Implied, 0xE8)
+  op(TAY, Implied, 0xA8)
+  op(TYA, Implied, 0x98)
+  op(DEY, Implied, 0x88)
+  op(INY, Implied, 0xC8)
+
+  op(ROL, Implied, 0x2A)
+  op(ROL, ZeroPage, 0x26)
+  op(ROL, ZeroPageX, 0x36)
+  op(ROL, Absolute, 0x2E)
+  op(ROL, AbsoluteX, 0x3E)
+
+  op(ROR, Implied, 0x6A)
+  op(ROR, ZeroPage, 0x66)
+  op(ROR, ZeroPageX, 0x76)
+  op(ROR, Absolute, 0x6E)
+  op(ROR, AbsoluteX, 0x7E)
+
+  op(RTI, Implied, 0x40)
+  op(RTS, Implied, 0x60)
+
+  op(SBC, Immediate, 0xE9)
+  op(SBC, ZeroPage, 0xE5)
+  op(SBC, ZeroPageX, 0xF5)
+  op(SBC, Absolute, 0xED)
+  op(SBC, AbsoluteX, 0xFD)
+  op(SBC, AbsoluteY, 0xF9)
+  op(SBC, IndexedX, 0xE1)
+  op(SBC, IndexedY, 0xF1)
+
+  op(STA, ZeroPage, 0x85)
+  op(STA, ZeroPageX, 0x95)
+  op(STA, Absolute, 0x8D)
+  op(STA, AbsoluteX, 0x9D)
+  op(STA, AbsoluteY, 0x99)
+  op(STA, IndexedX, 0x81)
+  op(STA, IndexedY, 0x91)
+
+  op(TXS, Implied, 0x9A)
+  op(TSX, Implied, 0xBA)
+  op(PHA, Implied, 0x48)
+  op(PLA, Implied, 0x68)
+  op(PHP, Implied, 0x08)
+  op(PLP, Implied, 0x28)
+
+  op(STX, ZeroPage, 0x86)
+  op(STX, ZeroPageY, 0x96)
+  op(STX, Absolute, 0x8E)
+
+  op(STY, ZeroPage, 0x84)
+  op(STY, ZeroPageX, 0x94)
+  op(STY, Absolute, 0x8C)
+
+  il(LAX, ZeroPage, 0xA7)
+  il(LAX, ZeroPageY, 0xB7)
+  il(LAX, Absolute, 0xAF)
+  il(LAX, AbsoluteY, 0xBF)
+  il(LAX, IndexedX, 0xA3)
+  il(LAX, IndexedY, 0xB3)
+
+  il(SAX, ZeroPage, 0x87)
+  il(SAX, ZeroPageY, 0x97)
+  il(SAX, Absolute, 0x8F)
+  il(TAS, AbsoluteY, 0x9B)
+  il(AHX, AbsoluteY, 0x9F)
+  il(SAX, IndexedX, 0x83)
+  il(AHX, IndexedY, 0x93)
+  il(SHY, AbsoluteX, 0x9C)
+
+  il(ANC, Immediate, 0x0B)
+  il(ALR, Immediate, 0x4B)
+  il(ARR, Immediate, 0x6B)
+  il(XAA, Immediate, 0x8B)
+  il(LXA, Immediate, 0xAB)
+  il(SBX, Immediate, 0xCB)
+
+  il(SLO, ZeroPage, 0x07)
+  il(SLO, ZeroPageX, 0x17)
+  il(SLO, IndexedX, 0x03)
+  il(SLO, IndexedY, 0x13)
+  il(SLO, Absolute, 0x0F)
+  il(SLO, AbsoluteX, 0x1F)
+  il(SLO, AbsoluteY, 0x1B)
+
+  il(RLA, ZeroPage, 0x27)
+  il(RLA, ZeroPageX, 0x37)
+  il(RLA, IndexedX, 0x23)
+  il(RLA, IndexedY, 0x33)
+  il(RLA, Absolute, 0x2F)
+  il(RLA, AbsoluteX, 0x3F)
+  il(RLA, AbsoluteY, 0x3B)
+
+  il(SRE, ZeroPage, 0x47)
+  il(SRE, ZeroPageX, 0x57)
+  il(SRE, IndexedX, 0x43)
+  il(SRE, IndexedY, 0x53)
+  il(SRE, Absolute, 0x4F)
+  il(SRE, AbsoluteX, 0x5F)
+  il(SRE, AbsoluteY, 0x5B)
+
+  il(RRA, ZeroPage, 0x67)
+  il(RRA, ZeroPageX, 0x77)
+  il(RRA, IndexedX, 0x63)
+  il(RRA, IndexedY, 0x73)
+  il(RRA, Absolute, 0x6F)
+  il(RRA, AbsoluteX, 0x7F)
+  il(RRA, AbsoluteY, 0x7B)
+
+  il(DCP, ZeroPage, 0xC7)
+  il(DCP, ZeroPageX, 0xD7)
+  il(DCP, IndexedX, 0xC3)
+  il(DCP, IndexedY, 0xD3)
+  il(DCP, Absolute, 0xCF)
+  il(DCP, AbsoluteX, 0xDF)
+  il(DCP, AbsoluteY, 0xDB)
+
+  il(ISC, ZeroPage, 0xE7)
+  il(ISC, ZeroPageX, 0xF7)
+  il(ISC, IndexedX, 0xE3)
+  il(ISC, IndexedY, 0xF3)
+  il(ISC, Absolute, 0xEF)
+  il(ISC, AbsoluteX, 0xFF)
+  il(ISC, AbsoluteY, 0xFB)
+
+  il(NOP, Immediate, 0x80)
+  il(NOP, ZeroPage, 0x44)
+  il(NOP, ZeroPageX, 0x54)
+  il(NOP, Absolute, 0x5C)
+  il(NOP, AbsoluteX, 0x1C)
+
+  cn(NOP, Immediate, 0x02)
+  cn(NOP, ZeroPage, 0x44)
+  cn(NOP, ZeroPageX, 0x54)
+  cn(NOP, Absolute, 0x5C)
+
+  cm(STZ, ZeroPage, 0x64)
+  cm(STZ, ZeroPageX, 0x74)
+  cm(STZ, Absolute, 0x9C)
+  cm(STZ, AbsoluteX, 0x9E)
+
+  cm(PHX, Implied, 0xDA)
+  cm(PHY, Implied, 0x5A)
+  cm(PLX, Implied, 0xFA)
+  cm(PLY, Implied, 0x7A)
+
+  cm(ORA, IndexedZ, 0x12)
+  cm(AND, IndexedZ, 0x32)
+  cm(EOR, IndexedZ, 0x52)
+  cm(ADC, IndexedZ, 0x72)
+  cm(STA, IndexedZ, 0x92)
+  cm(LDA, IndexedZ, 0xB2)
+  cm(CMP, IndexedZ, 0xD2)
+  cm(SBC, IndexedZ, 0xF2)
+
+  cm(TSB, ZeroPage, 0x04)
+  cm(TSB, Absolute, 0x0C)
+  cm(TRB, ZeroPage, 0x14)
+  cm(TRB, Absolute, 0x1C)
+
+  cm(BRA, Relative, 0x80)
+  cm(BIT, ZeroPageX, 0x34)
+  cm(BIT, AbsoluteX, 0x3C)
+  cm(INC, Implied, 0x1A)
+  cm(DEC, Implied, 0x3A)
+  cm(JMP, AbsoluteIndexedX, 0x7C)
+  cm(WAI, Implied, 0xCB)
+  cm(STP, Implied, 0xDB)
+
+  ce(CPZ, Immediate, 0xC2)
+  ce(CPZ, ZeroPage, 0xD4)
+  ce(CPZ, Absolute, 0xDC)
+  ce(DEZ, Implied, 0x3B)
+  ce(INZ, Implied,0x1B )
+  ce(DEC_W, ZeroPage, 0xC3)
+  ce(INC_W, ZeroPage, 0xE3)
+  ce(ASL_W, Absolute, 0xCB)
+  // TODO: or is it ROL_W?
+  ce(ROR_W, Absolute, 0xEB)
+  ce(ASR, Implied, 0x43)
+  ce(ASR, ZeroPage, 0x44)
+  ce(ASR, ZeroPageX, 0x54)
+  ce(LDZ, Immediate, 0xA3)
+  ce(LDZ, Absolute, 0xAB)
+  ce(LDZ, AbsoluteX, 0xBB)
+  ce(TAB, Implied, 0x5B)
+  ce(TBA, Implied, 0x7B)
+  ce(TAZ, Implied, 0x4B)
+  ce(TZA, Implied, 0x6B)
+  ce(TSY, Implied, 0x0B)
+  ce(TYS, Implied, 0x2B)
+  ce(PHW, WordImmediate, 0xF4)
+  ce(PHW, Absolute, 0xFC)
+  ce(PHZ, Implied, 0xDB)
+  ce(PLZ, Implied, 0xFB)
+//  ce(CLE, Implied, )
+//  ce(SEE, Implied, )
+//  ce(BSR, , )
+
+  hu(CLY, Implied, 0xC2)
+  hu(CLX, Implied, 0x82)
+  hu(CLA, Implied, 0x62)
+  hu(CSH, Implied, 0xD4)
+  hu(CSL, Implied, 0x54)
+  hu(HuSAX, Implied, 0x22)
+  hu(SAY, Implied, 0x42)
+  hu(SXY, Implied, 0x02)
+  hu(TAM, Immediate, 0x53)
+  hu(TMA, Immediate, 0x43)
+
+  em(ORA, Stack, 0x03)
+  em(ORA, IndexedSY, 0x13)
+  na(ORA, LongIndexedZ, 0x07)
+  na(ORA, LongIndexedY, 0x17)
+  na(ORA, LongAbsolute, 0x0F)
+  na(ORA, LongAbsoluteX, 0x1F)
+  em(AND, Stack, 0x23)
+  em(AND, IndexedSY, 0x33)
+  na(AND, LongIndexedZ, 0x27)
+  na(AND, LongIndexedY, 0x37)
+  na(AND, LongAbsolute, 0x2F)
+  na(AND, LongAbsoluteX, 0x3F)
+  em(EOR, Stack, 0x43)
+  em(EOR, IndexedSY, 0x53)
+  na(EOR, LongIndexedZ, 0x47)
+  na(EOR, LongIndexedY, 0x57)
+  na(EOR, LongAbsolute, 0x4F)
+  na(EOR, LongAbsoluteX, 0x5F)
+  em(ADC, Stack, 0x63)
+  em(ADC, IndexedSY, 0x73)
+  na(ADC, LongIndexedZ, 0x67)
+  na(ADC, LongIndexedY, 0x77)
+  na(ADC, LongAbsolute, 0x6F)
+  na(ADC, LongAbsoluteX, 0x7F)
+  em(STA, Stack, 0x83)
+  em(STA, IndexedSY, 0x93)
+  na(STA, LongIndexedZ, 0x87)
+  na(STA, LongIndexedY, 0x97)
+  na(STA, LongAbsolute, 0x8F)
+  na(STA, LongAbsoluteX, 0x9F)
+  em(LDA, Stack, 0xA3)
+  em(LDA, IndexedSY, 0xB3)
+  na(LDA, LongIndexedZ, 0xA7)
+  na(LDA, LongIndexedY, 0xB7)
+  na(LDA, LongAbsolute, 0xAF)
+  na(LDA, LongAbsoluteX, 0xBF)
+  em(CMP, Stack, 0xA3)
+  em(CMP, IndexedSY, 0xB3)
+  na(CMP, LongIndexedZ, 0xA7)
+  na(CMP, LongIndexedY, 0xB7)
+  na(CMP, LongAbsolute, 0xAF)
+  na(CMP, LongAbsoluteX, 0xBF)
+
+  em(COP, Immediate, 0x02)
+  em(XBA, Implied, 0xEB)
+  em(TXY, Implied, 0x9B)
+  em(TYX, Implied, 0xBB)
+
+
+  na(RTL, Implied, 0x6B)
+  na(JMP, LongAbsolute, 0x5C)
+  na(JMP, LongIndirect, 0x7C)
+  na(BRL, LongRelative, 0x82)
+
+  em(PHD, Implied, 0x0B)
+  em(PLD, Implied, 0x2B)
+  em(PHB, Implied, 0x8B)
+  em(PLB, Implied, 0xAB)
+  em(PHK, Implied, 0x4B)
+
+  na(REP, Immediate, 0xC2)
+  na(SEP, Immediate, 0xE2)
+
+  na(XCE, Implied, 0xFB)
+  na(TCD, Implied, 0x5B)
+  na(TDC, Implied, 0x7B)
+  na(TSC, Implied, 0x3B)
+  na(TCS, Implied, 0x1B)
+
+  for {
+    ((narrow, am), code) <- emulation65816Opcodes ++ opcodes ++ cmosOpcodes ++ native65816Opcodes
+    wide <- Opcode.widen(narrow)
+  } na(wide, if (am == Immediate) WordImmediate else am, code & 0xff)
+
+}

src/main/scala/millfork/output/MosInliningCalculator.scala

@@ -1,8 +1,9 @@
 package millfork.output
 
-import millfork.assembly.{AddrMode, AssemblyLine, Opcode, OpcodeClasses}
-import millfork.assembly.Opcode._
-import millfork.compiler.{ExpressionCompiler, MfCompiler}
+import millfork.assembly.AddrMode
+import millfork.assembly.mos.Opcode._
+import millfork.assembly.mos._
+import millfork.compiler.AbstractCompiler
 import millfork.env._
 import millfork.node._
 
@@ -14,7 +15,7 @@ import scala.collection.mutable
 
 case class InliningResult(potentiallyInlineableFunctions: Map[String, Int], nonInlineableFunctions: Set[String])
 
-object InliningCalculator {
+object MosInliningCalculator extends AbstractInliningCalculator[AssemblyLine] {
 
   private val sizes = Seq(64, 64, 8, 6, 5, 5, 4)
 
@@ -69,7 +70,7 @@ object InliningCalculator {
     case s: ArrayContents => getAllCalledFunctions(s.getAllExpressions)
     case s: FunctionDeclarationStatement => getAllCalledFunctions(s.address.toList) ++ getAllCalledFunctions(s.statements.getOrElse(Nil))
     case Assignment(VariableExpression(_), expr) => getAllCalledFunctions(expr :: Nil)
-    case AssemblyStatement(JSR, _, VariableExpression(name), true) => (name -> false) :: Nil
+    case MosAssemblyStatement(JSR, _, VariableExpression(name), true) => (name -> false) :: Nil
     case s: Statement => getAllCalledFunctions(s.getAllExpressions)
     case s: VariableExpression => Set(
           s.name,
@@ -110,4 +111,26 @@ object InliningCalculator {
     }) return None
     Some(result)
   }
+
+  def inline(code: List[AssemblyLine], inlinedFunctions: Map[String, List[AssemblyLine]], compiler: AbstractCompiler[AssemblyLine]): List[AssemblyLine] = {
+    code.flatMap {
+      case AssemblyLine(Opcode.JSR, AddrMode.Absolute | AddrMode.LongAbsolute, p, true) if inlinedFunctions.contains(p.toString) =>
+        val labelPrefix = compiler.nextLabel("ai")
+        inlinedFunctions(p.toString).map {
+          case line@AssemblyLine(_, _, MemoryAddressConstant(Label(label)), _) =>
+            val newLabel = MemoryAddressConstant(Label(labelPrefix + label))
+            line.copy(parameter = newLabel)
+          case l => l
+        }
+      case AssemblyLine(Opcode.JMP, AddrMode.Absolute, p, true) if inlinedFunctions.contains(p.toString) =>
+        val labelPrefix = compiler.nextLabel("ai")
+        inlinedFunctions(p.toString).map {
+          case line@AssemblyLine(_, _, MemoryAddressConstant(Label(label)), _) =>
+            val newLabel = MemoryAddressConstant(Label(labelPrefix + label))
+            line.copy(parameter = newLabel)
+          case l => l
+        } :+ AssemblyLine.implied(Opcode.RTS)
+      case x => List(x)
+    }
+  }
 }

src/main/scala/millfork/parser/AbstractSourceLoadingQueue.scala

@@ -9,26 +9,24 @@ import millfork.node.{ImportStatement, Position, Program}
 
 import scala.collection.mutable
 
-/**
-  * @author Karol Stasiak
-  */
-class SourceLoadingQueue(val initialFilenames: List[String], val includePath: List[String], val options: CompilationOptions) {
+abstract class AbstractSourceLoadingQueue[T](val initialFilenames: List[String],
+                                             val includePath: List[String],
+                                             val options: CompilationOptions) {
 
-  private val parsedModules = mutable.Map[String, Program]()
-  private val moduleQueue = mutable.Queue[() => Unit]()
+  protected val parsedModules: mutable.Map[String, Program] = mutable.Map[String, Program]()
+  protected val moduleQueue: mutable.Queue[() => Unit] = mutable.Queue[() => Unit]()
   val extension: String = ".mfk"
 
+  def enqueueStandardModules(): Unit
 
   def run(): Program = {
     initialFilenames.foreach { i =>
-      parseModule(extractName(i), includePath, Right(i), options)
+      parseModule(extractName(i), includePath, Right(i))
     }
     options.platform.startingModules.foreach {m =>
-      moduleQueue.enqueue(() => parseModule(m, includePath, Left(None), options))
-    }
-    if (options.flag(CompilationFlag.ZeropagePseudoregister)) {
-      moduleQueue.enqueue(() => parseModule("zp_reg", includePath, Left(None), options))
+      moduleQueue.enqueue(() => parseModule(m, includePath, Left(None)))
     }
+    enqueueStandardModules()
     while (moduleQueue.nonEmpty) {
       if (options.flag(CompilationFlag.SingleThreaded)) {
         moduleQueue.dequeueAll(_ => true).foreach(_())
@@ -51,13 +49,15 @@ class SourceLoadingQueue(val initialFilenames: List[String], val includePath: Li
     ErrorReporting.fatal(s"Module `$moduleName` not found", position)
   }
 
-  def parseModule(moduleName: String, includePath: List[String], why: Either[Option[Position], String], options: CompilationOptions): Unit = {
+  def createParser(filename: String, src: String, parentDir: String) : MfParser[T]
+
+  def parseModule(moduleName: String, includePath: List[String], why: Either[Option[Position], String]): Unit = {
     val filename: String = why.fold(p => lookupModuleFile(includePath, moduleName, p), s => s)
     ErrorReporting.debug(s"Parsing $filename")
     val path = Paths.get(filename)
     val parentDir = path.toFile.getAbsoluteFile.getParent
     val src = new String(Files.readAllBytes(path))
-    val parser = MfParser(filename, src, parentDir, options)
+    val parser = createParser(filename, src, parentDir)
     parser.toAst match {
       case Success(prog, _) =>
         parsedModules.synchronized {
@@ -65,7 +65,7 @@ class SourceLoadingQueue(val initialFilenames: List[String], val includePath: Li
           prog.declarations.foreach {
             case s@ImportStatement(m) =>
               if (!parsedModules.contains(m)) {
-                moduleQueue.enqueue(() => parseModule(m, parentDir :: includePath, Left(s.position), options))
+                moduleQueue.enqueue(() => parseModule(m, parentDir :: includePath, Left(s.position)))
               }
             case _ => ()
           }

src/main/scala/millfork/parser/MfParser.scala

@@ -3,7 +3,7 @@ package millfork.parser
 import java.nio.file.{Files, Paths}
 
 import fastparse.all._
-import millfork.assembly.{AddrMode, Opcode}
+import millfork.assembly.mos.Opcode
 import millfork.env._
 import millfork.error.ErrorReporting
 import millfork.node._
@@ -12,7 +12,7 @@ import millfork.{CompilationOptions, SeparatedList}
 /**
   * @author Karol Stasiak
   */
-case class MfParser(filename: String, input: String, currentDirectory: String, options: CompilationOptions) {
+abstract class MfParser[T](filename: String, input: String, currentDirectory: String, options: CompilationOptions) {
 
   var lastPosition = Position(filename, 1, 1, 0)
   var lastLabel = ""
@@ -147,7 +147,7 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
 
   val atom: P[Expression] = P(literalAtom | (position() ~ identifier).map { case (p, i) => VariableExpression(i).pos(p) })
 
-  val mlOperators = List(
+  val mfOperators = List(
     List("+=", "-=", "+'=", "-'=", "^=", "&=", "|=", "*=", "*'=", "<<=", ">>=", "<<'=", ">>'="),
     List("||", "^^"),
     List("&&"),
@@ -167,8 +167,8 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
     flags <- flags("const", "static", "volatile", "stack", "register") ~ HWS
     typ <- identifier ~ SWS
     name <- identifier ~/ HWS ~/ Pass
-    addr <- ("@" ~/ HWS ~/ mlExpression(1)).?.opaque("<address>") ~ HWS
-    initialValue <- ("=" ~/ HWS ~/ mlExpression(1)).? ~ HWS
+    addr <- ("@" ~/ HWS ~/ mfExpression(1)).?.opaque("<address>") ~ HWS
+    initialValue <- ("=" ~/ HWS ~/ mfExpression(1)).? ~ HWS
     _ <- &(EOL) ~/ ""
   } yield {
     Seq(VariableDeclarationStatement(name, typ,
@@ -191,33 +191,9 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
     ParameterDeclaration(typ, ByVariable(name)).pos(p)
   }
 
-  val appcSimple: P[ParamPassingConvention] = P("xy" | "yx" | "ax" | "ay" | "xa" | "ya" | "stack" | "a" | "x" | "y").!.map {
-    case "xy" => ByRegister(Register.XY)
-    case "yx" => ByRegister(Register.YX)
-    case "ax" => ByRegister(Register.AX)
-    case "ay" => ByRegister(Register.AY)
-    case "xa" => ByRegister(Register.XA)
-    case "ya" => ByRegister(Register.YA)
-    case "a" => ByRegister(Register.A)
-    case "x" => ByRegister(Register.X)
-    case "y" => ByRegister(Register.Y)
-    case x => ErrorReporting.fatal(s"Unknown assembly parameter passing convention: `$x`")
-  }
+  def asmParamDefinition: P[ParameterDeclaration]
 
-  val appcComplex: P[ParamPassingConvention] = P((("const" | "ref").! ~/ AWS).? ~ AWS ~ identifier) map {
-    case (None, name) => ByVariable(name)
-    case (Some("const"), name) => ByConstant(name)
-    case (Some("ref"), name) => ByReference(name)
-    case x => ErrorReporting.fatal(s"Unknown assembly parameter passing convention: `$x`")
-  }
-
-  val asmParamDefinition: P[ParameterDeclaration] = for {
-    p <- position()
-    typ <- identifier ~ SWS
-    appc <- appcSimple | appcComplex
-  } yield ParameterDeclaration(typ, appc).pos(p)
-
-  def arrayListElement: P[ArrayContents] = arrayStringContents | arrayLoopContents | mlExpression(nonStatementLevel).map(e => LiteralContents(List(e)))
+  def arrayListElement: P[ArrayContents] = arrayStringContents | arrayLoopContents | mfExpression(nonStatementLevel).map(e => LiteralContents(List(e)))
 
   def arrayListContents: P[ArrayContents] = ("[" ~/ AWS ~/ arrayListElement.rep(sep = AWS ~ "," ~/ AWS) ~ AWS ~ "]" ~/ Pass).map(c => CombinedContents(c.toList))
 
@@ -265,10 +241,10 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
 
   def arrayLoopContents: P[ArrayContents] = for {
       identifier <- "for" ~ SWS ~/ identifier ~/ HWS ~ "," ~/ HWS ~ Pass
-      start <- mlExpression(nonStatementLevel) ~ HWS ~ "," ~/ HWS ~/ Pass
+      start <- mfExpression(nonStatementLevel) ~ HWS ~ "," ~/ HWS ~/ Pass
       pos <- position()
       direction <- forDirection ~/ HWS ~/ "," ~/ HWS ~/ Pass
-      end <- mlExpression(nonStatementLevel)
+      end <- mfExpression(nonStatementLevel)
       body <- AWS ~ arrayContents
     } yield {
     val fixedDirection = direction match {
@@ -291,21 +267,21 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
     p <- position()
     bank <- bankDeclaration
     name <- "array" ~ !letterOrDigit ~/ SWS ~ identifier ~ HWS
-    length <- ("[" ~/ AWS ~/ mlExpression(nonStatementLevel) ~ AWS ~ "]").? ~ HWS
-    addr <- ("@" ~/ HWS ~/ mlExpression(1)).? ~/ HWS
+    length <- ("[" ~/ AWS ~/ mfExpression(nonStatementLevel) ~ AWS ~ "]").? ~ HWS
+    addr <- ("@" ~/ HWS ~/ mfExpression(1)).? ~/ HWS
     contents <- ("=" ~/ HWS ~/ arrayContents).? ~/ HWS
   } yield Seq(ArrayDeclarationStatement(name, bank, length, addr, contents).pos(p))
 
-  def tightMlExpression: P[Expression] = P(mlParenExpr | functionCall | mlIndexedExpression | atom) // TODO
+  def tightMfExpression: P[Expression] = P(mfParenExpr | functionCall | mfIndexedExpression | atom) // TODO
 
-  def tightMlExpressionButNotCall: P[Expression] = P(mlParenExpr | mlIndexedExpression | atom) // TODO
+  def tightMfExpressionButNotCall: P[Expression] = P(mfParenExpr | mfIndexedExpression | atom) // TODO
 
-  def mlExpression(level: Int): P[Expression] = {
-    val allowedOperators = mlOperators.drop(level).flatten
+  def mfExpression(level: Int): P[Expression] = {
+    val allowedOperators = mfOperators.drop(level).flatten
 
     def inner: P[SeparatedList[Expression, String]] = {
       for {
-        head <- tightMlExpression ~/ HWS
+        head <- tightMfExpression ~/ HWS
         maybeOperator <- StringIn(allowedOperators: _*).!.?
         maybeTail <- maybeOperator.fold[P[Option[List[(String, Expression)]]]](Pass.map(_ => None))(o => (HWS ~/ inner ~/ HWS).map(x2 => Some((o -> x2.head) :: x2.tail)))
       } yield {
@@ -314,9 +290,9 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
     }
 
     def p(list: SeparatedList[Expression, String], level: Int): Expression =
-      if (level == mlOperators.length) list.head
+      if (level == mfOperators.length) list.head
       else {
-        val xs = list.split(mlOperators(level).toSet(_))
+        val xs = list.split(mfOperators(level).toSet(_))
         xs.separators.distinct match {
           case Nil =>
             if (xs.tail.nonEmpty)
@@ -344,32 +320,32 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
     inner.map(x => p(x, 0))
   }
 
-  def mlLhsExpressionSimple: P[LhsExpression] = mlIndexedExpression | (position() ~ identifier).map { case (p, n) => VariableExpression(n).pos(p) }
+  def mfLhsExpressionSimple: P[LhsExpression] = mfIndexedExpression | (position() ~ identifier).map { case (p, n) => VariableExpression(n).pos(p) }
 
-  def mlLhsExpression: P[LhsExpression] = for {
-    (p, left) <- position() ~ mlLhsExpressionSimple
-    rightOpt <- (HWS ~ ":" ~/ HWS ~ mlLhsExpressionSimple).?
+  def mfLhsExpression: P[LhsExpression] = for {
+    (p, left) <- position() ~ mfLhsExpressionSimple
+    rightOpt <- (HWS ~ ":" ~/ HWS ~ mfLhsExpressionSimple).?
   } yield rightOpt.fold(left)(right => SeparateBytesExpression(left, right).pos(p))
 
 
-  def mlParenExpr: P[Expression] = P("(" ~/ AWS ~/ mlExpression(nonStatementLevel) ~ AWS ~/ ")")
+  def mfParenExpr: P[Expression] = P("(" ~/ AWS ~/ mfExpression(nonStatementLevel) ~ AWS ~/ ")")
 
-  def mlIndexedExpression: P[IndexedExpression] = for {
+  def mfIndexedExpression: P[IndexedExpression] = for {
     p <- position()
     array <- identifier
-    index <- HWS ~ "[" ~/ AWS ~/ mlExpression(nonStatementLevel) ~ AWS ~/ "]"
+    index <- HWS ~ "[" ~/ AWS ~/ mfExpression(nonStatementLevel) ~ AWS ~/ "]"
   } yield IndexedExpression(array, index).pos(p)
 
   def functionCall: P[FunctionCallExpression] = for {
     p <- position()
     name <- identifier
-    params <- HWS ~ "(" ~/ AWS ~/ mlExpression(nonStatementLevel).rep(min = 0, sep = AWS ~ "," ~/ AWS) ~ AWS ~/ ")" ~/ ""
+    params <- HWS ~ "(" ~/ AWS ~/ mfExpression(nonStatementLevel).rep(min = 0, sep = AWS ~ "," ~/ AWS) ~ AWS ~/ ")" ~/ ""
   } yield FunctionCallExpression(name, params.toList).pos(p)
 
-  val expressionStatement: P[Seq[ExecutableStatement]] = mlExpression(0).map(x => Seq(ExpressionStatement(x)))
+  val expressionStatement: P[Seq[ExecutableStatement]] = mfExpression(0).map(x => Seq(ExpressionStatement(x)))
 
   val assignmentStatement: P[Seq[ExecutableStatement]] =
-    (position() ~ mlLhsExpression ~ HWS ~ "=" ~/ HWS ~ mlExpression(1)).map {
+    (position() ~ mfLhsExpression ~ HWS ~ "=" ~/ HWS ~ mfExpression(1)).map {
       case (p, l, r) => Seq(Assignment(l, r).pos(p))
     }
 
@@ -386,65 +362,7 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
 
   def executableStatement: P[Seq[ExecutableStatement]] = (position() ~ P(keywordStatement | expressionStatement)).map { case (p, s) => s.map(_.pos(p)) }
 
-  // TODO: label and instruction in one line
-  def asmLabel: P[ExecutableStatement] = (identifier ~ HWS ~ ":" ~/ HWS).map(l => AssemblyStatement(Opcode.LABEL, AddrMode.DoesNotExist, VariableExpression(l), elidable = true))
-
-  //  def zeropageAddrModeHint: P[Option[Boolean]] = Pass
-
-  def asmOpcode: P[Opcode.Value] = (position() ~ letter.rep(exactly = 3).! ~ ("_W" | "_w").?.!).map { case (p, suffix, o) => Opcode.lookup(o + suffix, Some(p)) }
-
-  def asmExpression: P[Expression] = (position() ~ NoCut(
-    ("<" ~/ HWS ~ mlExpression(mathLevel)).map(e => HalfWordExpression(e, hiByte = false)) |
-      (">" ~/ HWS ~ mlExpression(mathLevel)).map(e => HalfWordExpression(e, hiByte = true)) |
-      mlExpression(mathLevel)
-  )).map { case (p, e) => e.pos(p) }
-
-  private val commaX = HWS ~ "," ~ HWS ~ ("X" | "x") ~ HWS
-  private val commaY = HWS ~ "," ~ HWS ~ ("Y" | "y") ~ HWS
-  private val commaZ = HWS ~ "," ~ HWS ~ ("Z" | "z") ~ HWS
-  private val commaS = HWS ~ "," ~ HWS ~ ("S" | "s") ~ HWS
-
-  val farKeyword: P[Unit] = P(("f" | "F") ~ ("a" | "A") ~ ("r" | "R"))
-
-  def asmParameter: P[(AddrMode.Value, Expression)] = {
-    (SWS ~ (
-      ("##" ~ asmExpression).map(AddrMode.WordImmediate -> _) |
-      ("#" ~ asmExpression).map(AddrMode.Immediate -> _) |
-        ("(" ~ HWS ~ asmExpression ~ HWS ~ ")" ~ commaY).map(AddrMode.IndexedY -> _) |
-        (farKeyword ~ HWS ~ "(" ~ HWS ~ asmExpression ~ HWS ~ ")" ~ commaY).map(AddrMode.LongIndexedY -> _) |
-        ("(" ~ HWS ~ asmExpression ~ commaS ~ ")" ~ commaY).map(AddrMode.IndexedSY -> _) |
-        ("(" ~ HWS ~ asmExpression ~ HWS ~ ")" ~ commaZ).map(AddrMode.IndexedZ -> _) |
-        ("(" ~ HWS ~ asmExpression ~ commaX ~ ")").map(AddrMode.IndexedX -> _) |
-        ("(" ~ HWS ~ asmExpression ~ HWS ~ ")").map(AddrMode.Indirect -> _) |
-        (farKeyword ~ HWS ~ "(" ~ HWS ~ asmExpression ~ HWS ~ ")").map(AddrMode.LongIndexedZ -> _) |
-        (farKeyword ~ HWS ~ asmExpression ~ commaX).map(AddrMode.LongAbsoluteX -> _) |
-        (farKeyword ~ HWS ~ asmExpression).map(AddrMode.LongAbsolute -> _) |
-        (asmExpression ~ commaS).map(AddrMode.Stack -> _) |
-        (asmExpression ~ commaX).map(AddrMode.AbsoluteX -> _) |
-        (asmExpression ~ commaY).map(AddrMode.AbsoluteY -> _) |
-        asmExpression.map(AddrMode.Absolute -> _)
-      )).?.map(_.getOrElse(AddrMode.Implied -> LiteralExpression(0, 1)))
-  }
-
-  def elidable: P[Boolean] = ("?".! ~/ HWS).?.map(_.isDefined)
-
-  def asmInstruction: P[ExecutableStatement] = {
-    val lineParser: P[(Boolean, Opcode.Value, (AddrMode.Value, Expression))] = !"}" ~ elidable ~/ asmOpcode ~/ asmParameter
-    lineParser.map { case (elid, op, param) =>
-      (op, param._1) match {
-        case (Opcode.SAX, AddrMode.Implied) => AssemblyStatement(Opcode.HuSAX, param._1, param._2, elid)
-        case (Opcode.SBX, AddrMode.Immediate) => AssemblyStatement(Opcode.SBX, param._1, param._2, elid)
-        case (Opcode.SAY, AddrMode.AbsoluteX) => AssemblyStatement(Opcode.SHY, param._1, param._2, elid)
-        case (Opcode.SBX, _) => AssemblyStatement(Opcode.SAX, param._1, param._2, elid)
-        case (_, AddrMode.Indirect) if op != Opcode.JMP && op != Opcode.JSR => AssemblyStatement(op, AddrMode.IndexedZ, param._2, elid)
-        case _ => AssemblyStatement(op, param._1, param._2, elid)
-      }
-    }
-  }
-
-  def asmMacro: P[ExecutableStatement] = ("+" ~/ HWS ~/ functionCall).map(ExpressionStatement)
-
-  def asmStatement: P[ExecutableStatement] = (position("assembly statement") ~ P(asmLabel | asmMacro | arrayContentsForAsm | asmInstruction)).map { case (p, s) => s.pos(p) } // TODO: macros
+  def asmStatement: P[ExecutableStatement]
 
   def statement: P[Seq[Statement]] = (position() ~ P(keywordStatement | variableDefinition(false) | expressionStatement)).map { case (p, s) => s.map(_.pos(p)) }
 
@@ -455,7 +373,7 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
   def executableStatements: P[Seq[ExecutableStatement]] = ("{" ~/ AWS ~/ executableStatement.rep(sep = NoCut(EOL) ~ !"}" ~/ Pass) ~/ AWS ~ "}").map(_.flatten)
 
   def dispatchLabel: P[ReturnDispatchLabel] =
-    ("default" ~ !letterOrDigit ~/ AWS ~/ ("(" ~/ position("default branch range") ~ AWS ~/ mlExpression(nonStatementLevel).rep(min = 0, sep = AWS ~ "," ~/ AWS) ~ AWS ~/ ")" ~/ "").?).map{
+    ("default" ~ !letterOrDigit ~/ AWS ~/ ("(" ~/ position("default branch range") ~ AWS ~/ mfExpression(nonStatementLevel).rep(min = 0, sep = AWS ~ "," ~/ AWS) ~ AWS ~/ ")" ~/ "").?).map{
       case None => DefaultReturnDispatchLabel(None, None)
       case Some((_, Seq())) => DefaultReturnDispatchLabel(None, None)
       case Some((_, Seq(e))) => DefaultReturnDispatchLabel(None, Some(e))
@@ -463,38 +381,38 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
       case Some((pos, _)) =>
         ErrorReporting.error("Invalid default branch declaration", Some(pos))
         DefaultReturnDispatchLabel(None, None)
-    } | mlExpression(nonStatementLevel).rep(min = 0, sep = AWS ~ "," ~/ AWS).map(exprs => StandardReturnDispatchLabel(exprs.toList))
+    } | mfExpression(nonStatementLevel).rep(min = 0, sep = AWS ~ "," ~/ AWS).map(exprs => StandardReturnDispatchLabel(exprs.toList))
 
   def dispatchBranch: P[ReturnDispatchBranch] = for {
     pos <- position()
     l <- dispatchLabel ~/ HWS ~/ "@" ~/ HWS
-    f <- tightMlExpressionButNotCall ~/ HWS
-    parameters <- ("(" ~/ position("dispatch actual parameters") ~ AWS ~/ mlExpression(nonStatementLevel).rep(min = 0, sep = AWS ~ "," ~/ AWS) ~ AWS ~/ ")" ~/ "").?
+    f <- tightMfExpressionButNotCall ~/ HWS
+    parameters <- ("(" ~/ position("dispatch actual parameters") ~ AWS ~/ mfExpression(nonStatementLevel).rep(min = 0, sep = AWS ~ "," ~/ AWS) ~ AWS ~/ ")" ~/ "").?
   } yield ReturnDispatchBranch(l, f, parameters.map(_._2.toList).getOrElse(Nil)).pos(pos)
 
   def dispatchStatementBody: P[Seq[ExecutableStatement]] = for {
-    indexer <- "[" ~/ AWS ~/ mlExpression(nonStatementLevel) ~/ AWS ~/ "]" ~/ AWS
+    indexer <- "[" ~/ AWS ~/ mfExpression(nonStatementLevel) ~/ AWS ~/ "]" ~/ AWS
     _ <- position("dispatch statement body")
-    parameters <- ("(" ~/ position("dispatch parameters") ~ AWS ~/ mlLhsExpression.rep(min = 0, sep = AWS ~ "," ~/ AWS) ~ AWS ~/ ")" ~/ "").?
+    parameters <- ("(" ~/ position("dispatch parameters") ~ AWS ~/ mfLhsExpression.rep(min = 0, sep = AWS ~ "," ~/ AWS) ~ AWS ~/ ")" ~/ "").?
     _ <- AWS ~/ position("dispatch statement body") ~/ "{" ~/ AWS
     branches <- dispatchBranch.rep(sep = EOL ~ !"}" ~/ Pass)
     _ <- AWS ~/ "}"
   } yield Seq(ReturnDispatchStatement(indexer, parameters.map(_._2.toList).getOrElse(Nil), branches.toList))
 
-  def returnOrDispatchStatement: P[Seq[ExecutableStatement]] = "return" ~ !letterOrDigit ~/ HWS ~ (dispatchStatementBody | mlExpression(nonStatementLevel).?.map(ReturnStatement).map(Seq(_)))
+  def returnOrDispatchStatement: P[Seq[ExecutableStatement]] = "return" ~ !letterOrDigit ~/ HWS ~ (dispatchStatementBody | mfExpression(nonStatementLevel).?.map(ReturnStatement).map(Seq(_)))
 
   def breakStatement: P[Seq[ExecutableStatement]] = ("break" ~ !letterOrDigit ~/ HWS ~ identifier.?).map(l => Seq(BreakStatement(l.getOrElse(""))))
 
   def continueStatement: P[Seq[ExecutableStatement]] = ("continue" ~ !letterOrDigit ~/ HWS ~ identifier.?).map(l => Seq(ContinueStatement(l.getOrElse(""))))
 
   def ifStatement: P[Seq[ExecutableStatement]] = for {
-    condition <- "if" ~ !letterOrDigit ~/ HWS ~/ mlExpression(nonStatementLevel)
+    condition <- "if" ~ !letterOrDigit ~/ HWS ~/ mfExpression(nonStatementLevel)
     thenBranch <- AWS ~/ executableStatements
     elseBranch <- (AWS ~ "else" ~/ AWS ~/ (ifStatement | executableStatements)).?
   } yield Seq(IfStatement(condition, thenBranch.toList, elseBranch.getOrElse(Nil).toList))
 
   def whileStatement: P[Seq[ExecutableStatement]] = for {
-    condition <- "while" ~ !letterOrDigit ~/ HWS ~/ mlExpression(nonStatementLevel)
+    condition <- "while" ~ !letterOrDigit ~/ HWS ~/ mfExpression(nonStatementLevel)
     body <- AWS ~ executableStatements
   } yield Seq(WhileStatement(condition, body.toList, Nil))
 
@@ -507,9 +425,9 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
 
   def forStatement: P[Seq[ExecutableStatement]] = for {
     identifier <- "for" ~ SWS ~/ identifier ~/ HWS ~ "," ~/ HWS ~ Pass
-    start <- mlExpression(nonStatementLevel) ~ HWS ~ "," ~/ HWS ~/ Pass
+    start <- mfExpression(nonStatementLevel) ~ HWS ~ "," ~/ HWS ~/ Pass
     direction <- forDirection ~/ HWS ~/ "," ~/ HWS ~/ Pass
-    end <- mlExpression(nonStatementLevel)
+    end <- mfExpression(nonStatementLevel)
     body <- AWS ~ executableStatements
   } yield Seq(ForStatement(identifier, start, end, direction, body.toList))
 
@@ -521,7 +439,7 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
   //noinspection MutatorLikeMethodIsParameterless
   def doWhileStatement: P[Seq[ExecutableStatement]] = for {
     body <- "do" ~ !letterOrDigit ~/ AWS ~ executableStatements ~/ AWS
-    condition <- "while" ~ !letterOrDigit ~/ HWS ~/ mlExpression(nonStatementLevel)
+    condition <- "while" ~ !letterOrDigit ~/ HWS ~/ mfExpression(nonStatementLevel)
   } yield Seq(DoWhileStatement(body.toList, Nil, condition))
 
 
@@ -536,7 +454,7 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
     returnType <- identifier ~ SWS
     name <- identifier ~ HWS
     params <- "(" ~/ AWS ~/ (if (flags("asm")) asmParamDefinition else paramDefinition).rep(sep = AWS ~ "," ~/ AWS) ~ AWS ~ ")" ~/ AWS
-    addr <- ("@" ~/ HWS ~/ mlExpression(1)).?.opaque("<address>") ~/ AWS
+    addr <- ("@" ~/ HWS ~/ mfExpression(1)).?.opaque("<address>") ~/ AWS
     statements <- (externFunctionBody | (if (flags("asm")) asmStatements else statements).map(l => Some(l))) ~/ Pass
   } yield {
     if (flags("interrupt") && flags("macro")) ErrorReporting.error(s"Interrupt function `$name` cannot be macros", Some(p))
@@ -550,32 +468,7 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
     if (flags("interrupt") && returnType != "void") ErrorReporting.error("Interrupt function `$name` has to return void", Some(p))
     if (addr.isEmpty && statements.isEmpty) ErrorReporting.error("Extern function `$name` must have an address", Some(p))
     if (statements.isEmpty && !flags("asm") && params.nonEmpty) ErrorReporting.error("Extern non-asm function `$name` cannot have parameters", Some(p))
-    if (flags("asm")) statements match {
-      case Some(Nil) => ErrorReporting.warn("Assembly function `$name` is empty, did you mean RTS or RTI", options, Some(p))
-      case Some(xs) =>
-        if (flags("interrupt")) {
-          if (xs.exists {
-            case AssemblyStatement(Opcode.RTS, _, _, _) => true
-            case _ => false
-          }) ErrorReporting.warn("Assembly interrupt function `$name` contains RTS, did you mean RTI?", options, Some(p))
-        } else {
-          if (xs.exists {
-            case AssemblyStatement(Opcode.RTI, _, _, _) => true
-            case _ => false
-          }) ErrorReporting.warn("Assembly non-interrupt function `$name` contains RTI, did you mean RTS?", options, Some(p))
-        }
-        if (!name.startsWith("__") && !flags("macro")) {
-          xs.last match {
-            case AssemblyStatement(Opcode.RTS, _, _, _) => () // OK
-            case AssemblyStatement(Opcode.RTI, _, _, _) => () // OK
-            case AssemblyStatement(Opcode.JMP, _, _, _) => () // OK
-            case _ =>
-              val validReturn = if (flags("interrupt")) "RTI" else "RTS"
-              ErrorReporting.warn(s"Non-macro assembly function `$name` should end in " + validReturn, options, Some(p))
-          }
-        }
-      case None => ()
-    }
+    if (flags("asm")) validateAsmFunctionBody(p, flags, name, statements)
     Seq(FunctionDeclarationStatement(name, returnType, params.toList,
       bank,
       addr,
@@ -588,6 +481,8 @@ case class MfParser(filename: String, input: String, currentDirectory: String, o
       flags("reentrant")).pos(p))
   }
 
+  def validateAsmFunctionBody(p: Position, flags: Set[String], name: String, statements: Option[List[Statement]])
+
   def importStatement: Parser[Seq[ImportStatement]] = ("import" ~ !letterOrDigit ~/ SWS ~/ identifier).map(x => Seq(ImportStatement(x)))
 
   def program: Parser[Program] = for {

src/main/scala/millfork/parser/MosParser.scala

@@ -0,0 +1,132 @@
+package millfork.parser
+
+import fastparse.all._
+import millfork.assembly.AddrMode
+import millfork.assembly.mos.Opcode
+import millfork.assembly.mos.AssemblyLine
+import millfork.env._
+import millfork.error.ErrorReporting
+import millfork.node._
+import millfork.CompilationOptions
+
+/**
+  * @author Karol Stasiak
+  */
+case class MosParser(filename: String, input: String, currentDirectory: String, options: CompilationOptions) extends MfParser[AssemblyLine](filename, input, currentDirectory, options) {
+
+  // TODO: label and instruction in one line
+  def asmLabel: P[ExecutableStatement] = (identifier ~ HWS ~ ":" ~/ HWS).map(l => MosAssemblyStatement(Opcode.LABEL, AddrMode.DoesNotExist, VariableExpression(l), elidable = true))
+
+  //  def zeropageAddrModeHint: P[Option[Boolean]] = Pass
+
+  def asmOpcode: P[Opcode.Value] = (position() ~ letter.rep(exactly = 3).! ~ ("_W" | "_w").?.!).map { case (p, suffix, o) => Opcode.lookup(o + suffix, Some(p)) }
+
+  def asmExpression: P[Expression] = (position() ~ NoCut(
+    ("<" ~/ HWS ~ mfExpression(mathLevel)).map(e => HalfWordExpression(e, hiByte = false)) |
+      (">" ~/ HWS ~ mfExpression(mathLevel)).map(e => HalfWordExpression(e, hiByte = true)) |
+      mfExpression(mathLevel)
+  )).map { case (p, e) => e.pos(p) }
+
+  private val commaX = HWS ~ "," ~ HWS ~ ("X" | "x") ~ HWS
+  private val commaY = HWS ~ "," ~ HWS ~ ("Y" | "y") ~ HWS
+  private val commaZ = HWS ~ "," ~ HWS ~ ("Z" | "z") ~ HWS
+  private val commaS = HWS ~ "," ~ HWS ~ ("S" | "s") ~ HWS
+
+  val farKeyword: P[Unit] = P(("f" | "F") ~ ("a" | "A") ~ ("r" | "R"))
+
+  def asmParameter: P[(AddrMode.Value, Expression)] = {
+    (SWS ~ (
+      ("##" ~ asmExpression).map(AddrMode.WordImmediate -> _) |
+      ("#" ~ asmExpression).map(AddrMode.Immediate -> _) |
+        ("(" ~ HWS ~ asmExpression ~ HWS ~ ")" ~ commaY).map(AddrMode.IndexedY -> _) |
+        (farKeyword ~ HWS ~ "(" ~ HWS ~ asmExpression ~ HWS ~ ")" ~ commaY).map(AddrMode.LongIndexedY -> _) |
+        ("(" ~ HWS ~ asmExpression ~ commaS ~ ")" ~ commaY).map(AddrMode.IndexedSY -> _) |
+        ("(" ~ HWS ~ asmExpression ~ HWS ~ ")" ~ commaZ).map(AddrMode.IndexedZ -> _) |
+        ("(" ~ HWS ~ asmExpression ~ commaX ~ ")").map(AddrMode.IndexedX -> _) |
+        ("(" ~ HWS ~ asmExpression ~ HWS ~ ")").map(AddrMode.Indirect -> _) |
+        (farKeyword ~ HWS ~ "(" ~ HWS ~ asmExpression ~ HWS ~ ")").map(AddrMode.LongIndexedZ -> _) |
+        (farKeyword ~ HWS ~ asmExpression ~ commaX).map(AddrMode.LongAbsoluteX -> _) |
+        (farKeyword ~ HWS ~ asmExpression).map(AddrMode.LongAbsolute -> _) |
+        (asmExpression ~ commaS).map(AddrMode.Stack -> _) |
+        (asmExpression ~ commaX).map(AddrMode.AbsoluteX -> _) |
+        (asmExpression ~ commaY).map(AddrMode.AbsoluteY -> _) |
+        asmExpression.map(AddrMode.Absolute -> _)
+      )).?.map(_.getOrElse(AddrMode.Implied -> LiteralExpression(0, 1)))
+  }
+
+  def elidable: P[Boolean] = ("?".! ~/ HWS).?.map(_.isDefined)
+
+  def asmInstruction: P[ExecutableStatement] = {
+    val lineParser: P[(Boolean, Opcode.Value, (AddrMode.Value, Expression))] = !"}" ~ elidable ~/ asmOpcode ~/ asmParameter
+    lineParser.map { case (elid, op, param) =>
+      (op, param._1) match {
+        case (Opcode.SAX, AddrMode.Implied) => MosAssemblyStatement(Opcode.HuSAX, param._1, param._2, elid)
+        case (Opcode.SBX, AddrMode.Immediate) => MosAssemblyStatement(Opcode.SBX, param._1, param._2, elid)
+        case (Opcode.SAY, AddrMode.AbsoluteX) => MosAssemblyStatement(Opcode.SHY, param._1, param._2, elid)
+        case (Opcode.SBX, _) => MosAssemblyStatement(Opcode.SAX, param._1, param._2, elid)
+        case (_, AddrMode.Indirect) if op != Opcode.JMP && op != Opcode.JSR => MosAssemblyStatement(op, AddrMode.IndexedZ, param._2, elid)
+        case _ => MosAssemblyStatement(op, param._1, param._2, elid)
+      }
+    }
+  }
+
+  def asmMacro: P[ExecutableStatement] = ("+" ~/ HWS ~/ functionCall).map(ExpressionStatement)
+
+  def asmStatement: P[ExecutableStatement] = (position("assembly statement") ~ P(asmLabel | asmMacro | arrayContentsForAsm | asmInstruction)).map { case (p, s) => s.pos(p) } // TODO: macros
+
+
+  val appcSimple: P[ParamPassingConvention] = P("xy" | "yx" | "ax" | "ay" | "xa" | "ya" | "stack" | "a" | "x" | "y").!.map {
+    case "xy" => ByRegister(MosRegister.XY)
+    case "yx" => ByRegister(MosRegister.YX)
+    case "ax" => ByRegister(MosRegister.AX)
+    case "ay" => ByRegister(MosRegister.AY)
+    case "xa" => ByRegister(MosRegister.XA)
+    case "ya" => ByRegister(MosRegister.YA)
+    case "a" => ByRegister(MosRegister.A)
+    case "x" => ByRegister(MosRegister.X)
+    case "y" => ByRegister(MosRegister.Y)
+    case x => ErrorReporting.fatal(s"Unknown assembly parameter passing convention: `$x`")
+  }
+
+  val appcComplex: P[ParamPassingConvention] = P((("const" | "ref").! ~/ AWS).? ~ AWS ~ identifier) map {
+    case (None, name) => ByVariable(name)
+    case (Some("const"), name) => ByConstant(name)
+    case (Some("ref"), name) => ByReference(name)
+    case x => ErrorReporting.fatal(s"Unknown assembly parameter passing convention: `$x`")
+  }
+
+  val asmParamDefinition: P[ParameterDeclaration] = for {
+    p <- position()
+    typ <- identifier ~ SWS
+    appc <- appcSimple | appcComplex
+  } yield ParameterDeclaration(typ, appc).pos(p)
+
+  def validateAsmFunctionBody(p: Position, flags: Set[String], name: String, statements: Option[List[Statement]]): Unit = {
+    statements match {
+      case Some(Nil) => ErrorReporting.warn("Assembly function `$name` is empty, did you mean RTS or RTI", options, Some(p))
+      case Some(xs) =>
+        if (flags("interrupt")) {
+          if (xs.exists {
+            case MosAssemblyStatement(Opcode.RTS, _, _, _) => true
+            case _ => false
+          }) ErrorReporting.warn("Assembly interrupt function `$name` contains RTS, did you mean RTI?", options, Some(p))
+        } else {
+          if (xs.exists {
+            case MosAssemblyStatement(Opcode.RTI, _, _, _) => true
+            case _ => false
+          }) ErrorReporting.warn("Assembly non-interrupt function `$name` contains RTI, did you mean RTS?", options, Some(p))
+        }
+        if (!name.startsWith("__") && !flags("macro")) {
+          xs.last match {
+            case MosAssemblyStatement(Opcode.RTS, _, _, _) => () // OK
+            case MosAssemblyStatement(Opcode.RTI, _, _, _) => () // OK
+            case MosAssemblyStatement(Opcode.JMP, _, _, _) => () // OK
+            case _ =>
+              val validReturn = if (flags("interrupt")) "RTI" else "RTS"
+              ErrorReporting.warn(s"Non-macro assembly function `$name` should end in " + validReturn, options, Some(p))
+          }
+        }
+      case None => ()
+    }
+  }
+}

src/main/scala/millfork/parser/MosSourceLoadingQueue.scala

@@ -0,0 +1,21 @@
+package millfork.parser
+
+import millfork.{CompilationFlag, CompilationOptions}
+import millfork.assembly.mos.AssemblyLine
+
+/**
+  * @author Karol Stasiak
+  */
+class MosSourceLoadingQueue(initialFilenames: List[String],
+                            includePath: List[String],
+                            options: CompilationOptions) extends AbstractSourceLoadingQueue[AssemblyLine](initialFilenames, includePath, options) {
+
+  override def createParser(filename: String, src: String, parentDir: String): MfParser[AssemblyLine] = MosParser(filename, src, parentDir, options)
+
+  def enqueueStandardModules(): Unit = {
+    if (options.flag(CompilationFlag.ZeropagePseudoregister)) {
+      moduleQueue.enqueue(() => parseModule("zp_reg", includePath, Left(None)))
+    }
+  }
+
+}

src/test/scala/millfork/test/ArraySuite.scala

@@ -1,7 +1,7 @@
 package millfork.test
 
 import millfork.{Cpu, OptimizationPresets}
-import millfork.assembly.opt.{AlwaysGoodOptimizations, DangerousOptimizations}
+import millfork.assembly.mos.opt.{AlwaysGoodOptimizations, DangerousOptimizations}
 import millfork.test.emu._
 import org.scalatest.{FunSuite, Matchers}
 

src/test/scala/millfork/test/AssemblyMacroSuite.scala

@@ -1,6 +1,6 @@
 package millfork.test
 
-import millfork.assembly.opt.DangerousOptimizations
+import millfork.assembly.mos.opt.DangerousOptimizations
 import millfork.test.emu.EmuBenchmarkRun
 import millfork.{Cpu, OptimizationPresets}
 import org.scalatest.{FunSuite, Matchers}

src/test/scala/millfork/test/AssemblyOptimizationSuite.scala

@@ -1,7 +1,7 @@
 package millfork.test
 
 import millfork.{Cpu, OptimizationPresets}
-import millfork.assembly.opt.{AlwaysGoodOptimizations, LaterOptimizations, VariableToRegisterOptimization}
+import millfork.assembly.mos.opt.{AlwaysGoodOptimizations, LaterOptimizations, VariableToRegisterOptimization}
 import millfork.test.emu.{EmuBenchmarkRun, EmuRun, EmuSuperOptimizedRun, EmuUltraBenchmarkRun}
 import org.scalatest.{FunSuite, Matchers}
 

src/test/scala/millfork/test/ForArraySuite.scala

@@ -1,7 +1,7 @@
 package millfork.test
 
 import millfork.{Cpu, OptimizationPresets}
-import millfork.assembly.opt.{AlwaysGoodOptimizations, DangerousOptimizations}
+import millfork.assembly.mos.opt.{AlwaysGoodOptimizations, DangerousOptimizations}
 import millfork.test.emu._
 import org.scalatest.{FunSuite, Matchers}
 

src/test/scala/millfork/test/SecondAssemblyOptimizationSuite.scala

@@ -1,6 +1,6 @@
 package millfork.test
 
-import millfork.assembly.opt.{AlwaysGoodOptimizations, LaterOptimizations, VariableToRegisterOptimization}
+import millfork.assembly.mos.opt.{AlwaysGoodOptimizations, LaterOptimizations, VariableToRegisterOptimization}
 import millfork.test.emu.{EmuBenchmarkRun, EmuRun, EmuUltraBenchmarkRun}
 import millfork.{Cpu, OptimizationPresets}
 import org.scalatest.{FunSuite, Matchers}

src/test/scala/millfork/test/emu/EmuOptimized65816Run.scala

@@ -1,6 +1,6 @@
 package millfork.test.emu
 
-import millfork.assembly.opt.{CmosOptimizations, SixteenOptimizations}
+import millfork.assembly.mos.opt.{CmosOptimizations, SixteenOptimizations}
 import millfork.{Cpu, OptimizationPresets}
 
 /**

src/test/scala/millfork/test/emu/EmuOptimized65CE02Run.scala

@@ -1,6 +1,6 @@
 package millfork.test.emu
 
-import millfork.assembly.opt.{CE02Optimizations, CmosOptimizations}
+import millfork.assembly.mos.opt.{CE02Optimizations, CmosOptimizations}
 import millfork.{Cpu, OptimizationPresets}
 
 /**

src/test/scala/millfork/test/emu/EmuOptimizedCmosRun.scala

@@ -1,6 +1,6 @@
 package millfork.test.emu
 
-import millfork.assembly.opt.{CmosOptimizations, ZeropageRegisterOptimizations}
+import millfork.assembly.mos.opt.{CmosOptimizations, ZeropageRegisterOptimizations}
 import millfork.{Cpu, OptimizationPresets}
 
 /**

src/test/scala/millfork/test/emu/EmuOptimizedHudsonRun.scala

@@ -1,6 +1,6 @@
 package millfork.test.emu
 
-import millfork.assembly.opt.{CmosOptimizations, HudsonOptimizations}
+import millfork.assembly.mos.opt.{CmosOptimizations, HudsonOptimizations}
 import millfork.{Cpu, OptimizationPresets}
 
 /**

src/test/scala/millfork/test/emu/EmuOptimizedInlinedRun.scala

@@ -1,6 +1,6 @@
 package millfork.test.emu
 
-import millfork.assembly.opt.{LaterOptimizations, ZeropageRegisterOptimizations}
+import millfork.assembly.mos.opt.{LaterOptimizations, ZeropageRegisterOptimizations}
 import millfork.{Cpu, OptimizationPresets}
 
 /**

src/test/scala/millfork/test/emu/EmuOptimizedRun.scala

@@ -1,6 +1,6 @@
 package millfork.test.emu
 
-import millfork.assembly.opt.{LaterOptimizations, ZeropageRegisterOptimizations}
+import millfork.assembly.mos.opt.{LaterOptimizations, ZeropageRegisterOptimizations}
 import millfork.{Cpu, OptimizationPresets}
 
 /**

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

@@ -7,16 +7,18 @@ import com.grapeshot.halfnes.{CPU, CPURAM}
 import com.loomcom.symon.InstructionTable.CpuBehavior
 import com.loomcom.symon.{Bus, Cpu, CpuState}
 import fastparse.core.Parsed.{Failure, Success}
-import millfork.assembly.opt.AssemblyOptimization
-import millfork.compiler.{CompilationContext, MfCompiler}
+import millfork.assembly.AssemblyOptimization
+import millfork.assembly.mos.AssemblyLine
+import millfork.compiler.mos.{CompilationContext, MosCompiler}
 import millfork.env.{Environment, InitializedArray, InitializedMemoryVariable, NormalFunction}
 import millfork.error.ErrorReporting
 import millfork.node.StandardCallGraph
 import millfork.node.opt.NodeOptimization
-import millfork.output.{Assembler, MemoryBank}
-import millfork.parser.MfParser
+import millfork.output.{MemoryBank, MosAssembler}
+import millfork.parser.MosParser
 import millfork.{CompilationFlag, CompilationOptions}
 import org.scalatest.Matchers
+
 import scala.collection.JavaConverters._
 
 /**
@@ -24,7 +26,7 @@ import scala.collection.JavaConverters._
   */
 case class Timings(nmos: Long, cmos: Long)
 
-class EmuRun(cpu: millfork.Cpu.Value, nodeOptimizations: List[NodeOptimization], assemblyOptimizations: List[AssemblyOptimization]) extends Matchers {
+class EmuRun(cpu: millfork.Cpu.Value, nodeOptimizations: List[NodeOptimization], assemblyOptimizations: List[AssemblyOptimization[AssemblyLine]]) extends Matchers {
 
   def apply(source: String): MemoryBank = {
     apply2(source)._2
@@ -116,7 +118,7 @@ class EmuRun(cpu: millfork.Cpu.Value, nodeOptimizations: List[NodeOptimization],
     if (!source.contains("__reg")) effectiveSource += "\n pointer __reg"
     if (source.contains("import zp_reg"))
       effectiveSource += Files.readAllLines(Paths.get("include/zp_reg.mfk"), StandardCharsets.US_ASCII).asScala.mkString("\n", "\n", "")
-    val parserF = MfParser("", effectiveSource, "", options)
+    val parserF = MosParser("", effectiveSource, "", options)
     parserF.toAst match {
       case Success(unoptimized, _) =>
         ErrorReporting.assertNoErrors("Parse failed")
@@ -133,7 +135,7 @@ class EmuRun(cpu: millfork.Cpu.Value, nodeOptimizations: List[NodeOptimization],
         // print unoptimized asm
         env.allPreallocatables.foreach {
           case f: NormalFunction =>
-            val unoptimized = MfCompiler.compile(CompilationContext(f.environment, f, 0, options))
+            val unoptimized = MosCompiler.compile(CompilationContext(f.environment, f, 0, options))
             unoptimizedSize += unoptimized.map(_.sizeInBytes).sum
           case d: InitializedArray =>
             unoptimizedSize += d.contents.length
@@ -147,7 +149,7 @@ class EmuRun(cpu: millfork.Cpu.Value, nodeOptimizations: List[NodeOptimization],
         // compile
         val env2 = new Environment(None, "")
         env2.collectDeclarations(program, options)
-        val assembler = new Assembler(program, env2, platform)
+        val assembler = new MosAssembler(program, env2, platform)
         val output = assembler.assemble(callGraph, assemblyOptimizations, options)
         println(";;; compiled: -----------------")
         output.asm.takeWhile(s => !(s.startsWith(".") && s.contains("= $"))).filterNot(_.contains("; DISCARD_")).foreach(println)
@@ -222,7 +224,7 @@ class EmuRun(cpu: millfork.Cpu.Value, nodeOptimizations: List[NodeOptimization],
     cpu.setBus(bus)
     cpu.setProgramCounter(org)
     cpu.setStackPointer(0xff)
-    val legal = Assembler.getStandardLegalOpcodes
+    val legal = MosAssembler.getStandardLegalOpcodes
 
     var countNmos = 0L
     var countCmos = 0L

src/test/scala/millfork/test/emu/EmuSuperOptimizedInliningRun.scala

@@ -1,6 +1,6 @@
 package millfork.test.emu
 
-import millfork.assembly.opt.SuperOptimizer
+import millfork.assembly.mos.opt.SuperOptimizer
 import millfork.{Cpu, OptimizationPresets}
 
 /**

src/test/scala/millfork/test/emu/EmuSuperoptimizedRun.scala

@@ -1,6 +1,6 @@
 package millfork.test.emu
 
-import millfork.assembly.opt.SuperOptimizer
+import millfork.assembly.mos.opt.SuperOptimizer
 import millfork.{Cpu, OptimizationPresets}
 
 /**

src/test/scala/millfork/test/emu/EmuUndocumentedRun.scala

@@ -1,6 +1,6 @@
 package millfork.test.emu
 
-import millfork.assembly.opt.{LaterOptimizations, UndocumentedOptimizations}
+import millfork.assembly.mos.opt.{LaterOptimizations, UndocumentedOptimizations}
 import millfork.{Cpu, OptimizationPresets}
 
 /**