fix compiler error and codegen fault on signed value bitwise operation

codeOptimizers/src/prog8/optimizer/UnusedCodeRemover.kt

@@ -157,6 +157,12 @@ class UnusedCodeRemover(private val program: Program,
         return noModifications
     }
 
+    override fun after(assignment: Assignment, parent: Node): Iterable<IAstModification> {
+        if(assignment.target isSameAs assignment.value)
+            return listOf(IAstModification.Remove(assignment, parent as IStatementContainer))
+        return noModifications
+    }
+
     private fun deduplicateAssignments(statements: List<Statement>, scope: IStatementContainer): List<IAstModification> {
         // removes 'duplicate' assignments that assign the same target directly after another, unless it is a function call
         val linesToRemove = mutableListOf<Assignment>()

compiler/src/prog8/compiler/astprocessing/AstChecker.kt

@@ -480,7 +480,9 @@ internal class AstChecker(private val program: Program,
                         errors.err("target datatype is unknown", assignment.target.position)
                     // otherwise, another error about missing symbol is already reported.
                 } else {
-                    errors.err("type of value $valueDt doesn't match target $targetDt", assignment.value.position)
+                    // allow bitwise operations on different types as long as the size is the same
+                    if (!((assignment.value as? BinaryExpression)?.operator in BitwiseOperators && targetDt.isBytes && valueDt.isBytes || targetDt.isWords && valueDt.isWords))
+                        errors.err("type of value $valueDt doesn't match target $targetDt", assignment.value.position)
                 }
             }
         }
@@ -1607,8 +1609,11 @@ internal class AstChecker(private val program: Program,
         else if(sourceDatatype== DataType.FLOAT && targetDatatype in IntegerDatatypes)
             errors.err("cannot assign float to ${targetDatatype.name.lowercase()}; possible loss of precision. Suggestion: round the value or revert to integer arithmetic", position)
         else {
-            if(targetDatatype!=DataType.UWORD && sourceDatatype !in PassByReferenceDatatypes)
+            if(targetDatatype!=DataType.UWORD && sourceDatatype !in PassByReferenceDatatypes) {
-                errors.err("type of value $sourceDatatype doesn't match target $targetDatatype", position)
+                // allow bitwise operations on different types as long as the size is the same
+                if (!((sourceValue as? BinaryExpression)?.operator in BitwiseOperators && targetDatatype.equalsSize(sourceDatatype)))
+                    errors.err("type of value $sourceDatatype doesn't match target $targetDatatype", position)
+            }
         }
 
         return false

compiler/src/prog8/compiler/astprocessing/BeforeAsmAstChanger.kt

@@ -93,6 +93,11 @@ internal class BeforeAsmAstChanger(val program: Program,
                             )
                         }
                     } else {
+                        if(binExpr.left isSameAs assignment.target)
+                            return noModifications
+                        val typeCast = binExpr.left as? TypecastExpression
+                        if(typeCast!=null && typeCast.expression isSameAs assignment.target)
+                            return noModifications
                         val sourceDt = binExpr.left.inferType(program).getOrElse { throw AssemblyError("unknown dt") }
                         val (_, left) = binExpr.left.typecastTo(assignment.target.inferType(program).getOrElse { throw AssemblyError(
                             "unknown dt"

compiler/src/prog8/compiler/astprocessing/TypecastsAdder.kt

@@ -133,9 +133,16 @@ class TypecastsAdder(val program: Program, val options: CompilationOptions, val
                         return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
                     }
                     if(leftDt istype DataType.WORD && rightDt.oneOf(DataType.UBYTE, DataType.UWORD)) {
-                        // cast left to unsigned
+                        // cast left to unsigned word. Cast right to unsigned word if it is ubyte
-                        val cast = TypecastExpression(expr.left, rightDt.getOr(DataType.UNDEFINED), true, expr.left.position)
+                        val mods = mutableListOf<IAstModification>()
-                        return listOf(IAstModification.ReplaceNode(expr.left, cast, expr))
+                        val cast = TypecastExpression(expr.left, DataType.UWORD, true, expr.left.position)
+                        mods += IAstModification.ReplaceNode(expr.left, cast, expr)
+                        if(rightDt istype DataType.UBYTE) {
+                            mods += IAstModification.ReplaceNode(expr.right,
+                                TypecastExpression(expr.right, DataType.UWORD, true, expr.right.position),
+                                expr)
+                        }
+                        return mods
                     }
                     if(rightDt istype DataType.BYTE && leftDt.oneOf(DataType.UBYTE, DataType.UWORD)) {
                         // cast right to unsigned
@@ -143,9 +150,16 @@ class TypecastsAdder(val program: Program, val options: CompilationOptions, val
                         return listOf(IAstModification.ReplaceNode(expr.right, cast, expr))
                     }
                     if(rightDt istype DataType.WORD && leftDt.oneOf(DataType.UBYTE, DataType.UWORD)) {
-                        // cast right to unsigned
+                        // cast right to unsigned word. Cast left to unsigned word if it is ubyte
-                        val cast = TypecastExpression(expr.right, leftDt.getOr(DataType.UNDEFINED), true, expr.right.position)
+                        val mods = mutableListOf<IAstModification>()
-                        return listOf(IAstModification.ReplaceNode(expr.right, cast, expr))
+                        val cast = TypecastExpression(expr.right, DataType.UWORD, true, expr.right.position)
+                        mods += IAstModification.ReplaceNode(expr.right, cast, expr)
+                        if(leftDt istype DataType.UBYTE) {
+                            mods += IAstModification.ReplaceNode(expr.left,
+                                TypecastExpression(expr.left, DataType.UWORD, true, expr.left.position),
+                                expr)
+                        }
+                        return mods
                     }
                 }
 

examples/test.p8

@@ -4,18 +4,32 @@
 main {
 
     sub start() {
+        ubyte ub = 123
+        byte bb = -100
+        uword uw = 12345
+        word ww = -12345
 
-        uword table = memory("table", 100, 0)
+        ub |= 63    ; vm/c64 ok (127)
+        bb |= 63    ; vm/c64 ok (-65)
+        uw |= 63    ; vm/c64 ok (12351)
+        ww |= 63    ; vm/c64 ok (-12289)
 
-        ubyte pos
+        txt.print_ub(ub)
-        for pos in 0 to 7 {
+        txt.spc()
-            pokew(table + 64 + pos*2, ($000a-pos)*200)
+        txt.print_b(bb)
-        }
+        txt.spc()
+        txt.print_uw(uw)
+        txt.spc()
+        txt.print_w(ww)
+        txt.nl()
 
-        for pos in 0 to 7 {
+        uw |= 16384  ; vm/c64 ok (28735)
-            txt.print_uw(peekw(table+64+pos*2))
+        ww |= 8192   ; vm/c64 ok (-4097)
-            txt.nl()
+
-        }
+        txt.print_uw(uw)
+        txt.spc()
+        txt.print_w(ww)
+        txt.nl()
     }
 }