6809: Update emulators and fix decimal subtraction

src/main/scala/millfork/compiler/m6809/M6809LargeBuiltins.scala

@@ -116,6 +116,7 @@ object M6809LargeBuiltins {
     }
     val sizeInBytes = AbstractExpressionCompiler.getExpressionType(ctx, target).size
     val byteLoads = M6809ExpressionCompiler.compileToByteReads(ctx, argument, sizeInBytes)
+    val needsAPreserved = byteLoads.tails.toList.tail.map(_.exists(_.exists(_.readsRegister(M6809Register.A))))
     val result = new ListBuffer[MLine]()
     val targetAddr: Option[Constant] = M6809ExpressionCompiler.compileAddressToX(ctx, target) match {
       case List(MLine(LDX, Immediate, addr, _, _)) => Some(addr)
@@ -152,17 +153,28 @@ object M6809LargeBuiltins {
         case (SUBA, _) =>
           targetAddr match {
             case Some(addr) =>
-              if (i == firstNonzeroByte) {
-                result ++= ldb
-              } else {
-                result ++= M6809ExpressionCompiler.stashCarryIfNeeded(ctx, ldb)
+              val stashCC = i != firstNonzeroByte
+              if (stashCC) result += MLine.pp(PSHS, M6809Register.CC)
+              result ++= ldb
+              if (needsAPreserved(i)) {
+                // TODO: optimize?
+                result += MLine.pp(PSHS, M6809Register.A)
               }
               result += MLine.pp(PSHS, M6809Register.B)
               result += MLine.immediate(LDA, if (i == firstNonzeroByte) 0x9a else 0x99)
               result += MLine.accessAndPullS(SUBA)
+              if (needsAPreserved(i)) {
+                // TODO: optimize?
+                result += MLine.pp(PULS, M6809Register.B)
+              }
+              if (stashCC) result += MLine.pp(PULS, M6809Register.CC)
               result += MLine.absolute(if (i == firstNonzeroByte) ADDA else ADCA, addr + (sizeInBytes - 1 - i))
               result += MLine.inherent(DAA)
               result += MLine.absolute(STA, addr + (sizeInBytes - 1 - i))
+              if (needsAPreserved(i)) {
+                // TODO: optimize?
+                result += MLine.tfr(M6809Register.B, M6809Register.A)
+              }
             case None =>
               result ++= M6809ExpressionCompiler.stashXIfNeeded(ctx, ldb)
               result += MLine.pp(PSHS, M6809Register.B)

src/test/scala/millfork/test/ByteDecimalMathSuite.scala

@@ -152,8 +152,7 @@ class ByteDecimalMathSuite extends FunSuite with Matchers with AppendedClues {
   }
 
   test("In-place decimal word subtraction") {
-    // TODO: enable 6809 after the DAA bug in the emulator is fixed
-    EmuCrossPlatformBenchmarkRun(Cpu.Mos, Cpu.Z80, Cpu.Intel8080, Cpu.Sharp, Cpu.Ricoh, Cpu.Intel8086/*, Cpu.Motorola6809*/)(
+    EmuCrossPlatformBenchmarkRun(Cpu.Mos, Cpu.Z80, Cpu.Intel8080, Cpu.Sharp, Cpu.Ricoh, Cpu.Intel8086, Cpu.Motorola6809)(
       """
         | word output @$c000
         | word a
@@ -167,8 +166,7 @@ class ByteDecimalMathSuite extends FunSuite with Matchers with AppendedClues {
   }
 
   test("In-place decimal long subtraction") {
-    // TODO: enable 6809 after the DAA bug in the emulator is fixed
-    EmuCrossPlatformBenchmarkRun(Cpu.Mos, Cpu.Z80, Cpu.Intel8080, Cpu.Sharp, Cpu.Ricoh, Cpu.Intel8086/*, Cpu.Motorola6809*/)(
+    EmuCrossPlatformBenchmarkRun(Cpu.Mos, Cpu.Z80, Cpu.Intel8080, Cpu.Sharp, Cpu.Ricoh, Cpu.Intel8086, Cpu.Motorola6809)(
       """
         | long output @$c000
         | word a
@@ -245,8 +243,7 @@ class ByteDecimalMathSuite extends FunSuite with Matchers with AppendedClues {
   }
 
   test("Decimal left shift test 3") {
-    // TODO: enable 6809 after the DAA bug in the emulator is fixed
-    EmuUnoptimizedCrossPlatformRun(Cpu.Mos, Cpu.Z80, Cpu.Intel8080, Cpu.Sharp, Cpu.Ricoh, Cpu.Intel8086/*, Cpu.Motorola6809*/)(
+    EmuUnoptimizedCrossPlatformRun(Cpu.Mos, Cpu.Z80, Cpu.Intel8080, Cpu.Sharp, Cpu.Ricoh, Cpu.Intel8086, Cpu.Motorola6809)(
       """
         | word output @$c000
         | void main () {
@@ -260,8 +257,7 @@ class ByteDecimalMathSuite extends FunSuite with Matchers with AppendedClues {
   }
 
   test("Decimal left shift test 4") {
-    // TODO: enable 6809 after the DAA bug in the emulator is fixed
-    EmuUnoptimizedCrossPlatformRun(Cpu.Mos, Cpu.Z80, Cpu.Intel8080, Cpu.Sharp, Cpu.Ricoh, Cpu.Intel8086/*, Cpu.Motorola6809*/)(
+    EmuUnoptimizedCrossPlatformRun(Cpu.Mos, Cpu.Z80, Cpu.Intel8080, Cpu.Sharp, Cpu.Ricoh, Cpu.Intel8086, Cpu.Motorola6809)(
       """
         | long output @$c000
         | void main () {

src/test/scala/millfork/test/emu/EmuM6809Run.scala

@@ -15,8 +15,9 @@ import millfork.error.ConsoleLogger
 import millfork.node.opt.NodeOptimization
 import millfork.node.{Program, StandardCallGraph}
 import millfork.output.{M6809Assembler, MemoryBank}
-import millfork.parser.{M6809Parser, MosParser, PreprocessingResult, Preprocessor, Z80Parser}
-import org.roug.osnine.{BusStraight, MC6809}
+import millfork.parser.{M6809Parser, PreprocessingResult, Preprocessor}
+import org.roug.usim.mc6809.MC6809
+import org.roug.usim.BusStraight
 import org.scalatest.Matchers
 
 import scala.collection.JavaConverters._

src/test/scala/millfork/test/emu/M6809Memory.scala

@@ -1,7 +1,7 @@
 package millfork.test.emu
 
 import millfork.output.MemoryBank
-import org.roug.osnine.{Bus8Motorola, MemorySegment}
+import org.roug.usim.MemorySegment
 
 /**
   * @author Karol Stasiak