From 1decf2f0874ca8782bb009864d36018c5019d2cd Mon Sep 17 00:00:00 2001
From: Karol Stasiak <karol.m.stasiak@gmail.com>
Date: Tue, 22 Sep 2020 17:59:14 +0200
Subject: [PATCH] 65816: Various codegen bugfixes

---
 .../mos/opt/SixteenOptimizations.scala         |  6 ++++++
 .../compiler/mos/MosExpressionCompiler.scala   |  2 +-
 .../scala/millfork/output/MosAssembler.scala   | 18 ++++++++++++------
 .../emu/EmuUnoptimizedCrossPlatformRun.scala   |  5 +++++
 4 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/src/main/scala/millfork/assembly/mos/opt/SixteenOptimizations.scala b/src/main/scala/millfork/assembly/mos/opt/SixteenOptimizations.scala
index 79d0341e..3e7aa46d 100644
--- a/src/main/scala/millfork/assembly/mos/opt/SixteenOptimizations.scala
+++ b/src/main/scala/millfork/assembly/mos/opt/SixteenOptimizations.scala
@@ -31,6 +31,12 @@ object SixteenOptimizations {
     (Elidable & HasOpcode(XBA) & DoesntMatterWhatItDoesWith(State.A, State.AH, State.N, State.Z)) ~~> { code =>
       Nil
     },
+    (Elidable & HasOpcode(XBA) & DoesntMatterWhatItDoesWith(State.N, State.Z) & HasAccu8 & HasIndex8) ~
+    (Elidable & HasOpcode(TAX)) ~
+    (Elidable & HasOpcode(XBA)) ~
+    (Elidable & HasOpcode(TXA) & DoesntMatterWhatItDoesWith(State.X, State.AH)) ~~> { code =>
+      List(code.head)
+    },
   )
 
   val RepSepWeakening = new RuleBasedAssemblyOptimization("REP/SEP weakening",
diff --git a/src/main/scala/millfork/compiler/mos/MosExpressionCompiler.scala b/src/main/scala/millfork/compiler/mos/MosExpressionCompiler.scala
index a0ee7650..92285d87 100644
--- a/src/main/scala/millfork/compiler/mos/MosExpressionCompiler.scala
+++ b/src/main/scala/millfork/compiler/mos/MosExpressionCompiler.scala
@@ -788,7 +788,7 @@ object MosExpressionCompiler extends AbstractExpressionCompiler[AssemblyLine] {
                     if (exprType.size > target.typ.size) {
                       ctx.log.error(s"Variable `$target.name` is too small", expr.position)
                       Nil
-                    } else if (exprType.size == 2 && target.typ.size == 2 && ctx.options.flag(CompilationFlag.EmitNative65816Opcodes)) {
+                    } else if (exprType.size == 2 && AbstractExpressionCompiler.getExpressionType(ctx, expr).size == 2 && target.typ.size == 2 && ctx.options.flag(CompilationFlag.EmitNative65816Opcodes)) {
                       AssemblyLine.accu16 :: (AssemblyLine.variable(ctx, LDA_W, source) ++ AssemblyLine.variable(ctx, STA_W, target) :+ AssemblyLine.accu8)
                     } else {
                       val copyFromLo  = List.tabulate(exprType.size)(i => AssemblyLine.variable(ctx, LDA, source, i) ++ AssemblyLine.variable(ctx, STA, target, i))
diff --git a/src/main/scala/millfork/output/MosAssembler.scala b/src/main/scala/millfork/output/MosAssembler.scala
index b4bd37c2..4d6db838 100644
--- a/src/main/scala/millfork/output/MosAssembler.scala
+++ b/src/main/scala/millfork/output/MosAssembler.scala
@@ -785,12 +785,18 @@ object MosAssembler {
   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(CMP, Stack, 0xC3)
+  em(CMP, IndexedSY, 0xD3)
+  na(CMP, LongIndexedZ, 0xC7)
+  na(CMP, LongIndexedY, 0xD7)
+  na(CMP, LongAbsolute, 0xCF)
+  na(CMP, LongAbsoluteX, 0xDF)
+  em(SBC, Stack, 0xE3)
+  em(SBC, IndexedSY, 0xF3)
+  na(SBC, LongIndexedZ, 0xE7)
+  na(SBC, LongIndexedY, 0xF7)
+  na(SBC, LongAbsolute, 0xEF)
+  na(SBC, LongAbsoluteX, 0xFF)
 
   em(COP, Immediate, 0x02)
   em(XBA, Implied, 0xEB)
diff --git a/src/test/scala/millfork/test/emu/EmuUnoptimizedCrossPlatformRun.scala b/src/test/scala/millfork/test/emu/EmuUnoptimizedCrossPlatformRun.scala
index e204dd16..fdda69ca 100644
--- a/src/test/scala/millfork/test/emu/EmuUnoptimizedCrossPlatformRun.scala
+++ b/src/test/scala/millfork/test/emu/EmuUnoptimizedCrossPlatformRun.scala
@@ -10,6 +10,7 @@ object EmuUnoptimizedCrossPlatformRun {
   def apply(platforms: Cpu.Value*)(source: String)(verifier: MemoryBank => Unit): Unit = {
     val (_, mm) = if (platforms.contains(Cpu.Mos) || platforms.contains(Cpu.StrictMos)) EmuUnoptimizedRun.apply2(source) else Timings(-1, -1) -> null
     val (_, mc) = if (platforms.contains(Cpu.Cmos)) EmuUnoptimizedCmosRun.apply2(source) else Timings(-1, -1) -> null
+    val (_, ma) = if (platforms.contains(Cpu.Sixteen)) EmuUnoptimizedNative65816Run.apply2(source) else Timings(-1, -1) -> null
     val (_, mn) = if (platforms.contains(Cpu.Ricoh)) EmuUnoptimizedRicohRun.apply2(source) else Timings(-1, -1) -> null
     val (_, mz) = if (platforms.contains(Cpu.Z80)) EmuUnoptimizedZ80Run.apply2(source) else Timings(-1, -1) -> null
     val (_, mi) = if (platforms.contains(Cpu.Intel8080)) EmuUnoptimizedIntel8080Run.apply2(source) else Timings(-1, -1) -> null
@@ -24,6 +25,10 @@ object EmuUnoptimizedCrossPlatformRun {
       println(f"Running Ricoh")
       verifier(mn)
     }
+    if (Settings.enableWdc85816Tests && platforms.contains(Cpu.Sixteen)) {
+      println(f"Running 65816")
+      verifier(ma)
+    }
     if (Settings.enable65C02Tests && platforms.contains(Cpu.Cmos)) {
       println(f"Running 65C02")
       verifier(mc)