Fixed namespace lookup errors related to variable initialization. Removed many X register clobbers.

compiler/res/prog8lib/c64utils.p8

@@ -47,9 +47,10 @@ asmsub  byte2decimal  (ubyte value @ A) -> clobbers() -> (ubyte @ Y, ubyte @ X,
 	}}
 }
 
-asmsub  ubyte2hex  (ubyte value @ A) -> clobbers(X) -> (ubyte @ A, ubyte @ Y)  {
+asmsub  ubyte2hex  (ubyte value @ A) -> clobbers() -> (ubyte @ A, ubyte @ Y)  {
 	; ---- A to hex string in AY (first hex char in A, second hex char in Y)
 	%asm {{
+		stx  c64.SCRATCH_ZPREGX
 		pha
 		and  #$0f
 		tax
@@ -61,6 +62,7 @@ asmsub  ubyte2hex  (ubyte value @ A) -> clobbers(X) -> (ubyte @ A, ubyte @ Y)  {
 		lsr  a
 		tax
 		lda  hex_digits,x
+		ldx  c64.SCRATCH_ZPREGX
 		rts
 
 hex_digits	.text "0123456789abcdef"	; can probably be reused for other stuff as well
@@ -69,13 +71,13 @@ hex_digits	.text "0123456789abcdef"	; can probably be reused for other stuff as
 
 
 		str  word2hex_output = "1234"   ; 0-terminated, to make printing easier
-asmsub  uword2hex  (uword value @ AY) -> clobbers(A,X,Y) -> ()  {
+asmsub  uword2hex  (uword value @ AY) -> clobbers(A,Y) -> ()  {
 	; ---- convert 16 bit uword in A/Y into 4-character hexadecimal string into memory  'word2hex_output'
 	%asm {{
 		sta  c64.SCRATCH_ZPREG
 		tya
 		jsr  ubyte2hex
-		stx  word2hex_output
+		sta  word2hex_output
 		sty  word2hex_output+1
 		lda  c64.SCRATCH_ZPREG
 		jsr  ubyte2hex
@@ -86,7 +88,7 @@ asmsub  uword2hex  (uword value @ AY) -> clobbers(A,X,Y) -> ()  {
 }
 
 		ubyte[3]  word2bcd_bcdbuff = [0, 0, 0]
-asmsub  uword2bcd  (uword value @ AY) -> clobbers(A,X) -> ()  {
+asmsub  uword2bcd  (uword value @ AY) -> clobbers(A,Y) -> ()  {
 	; Convert an 16 bit binary value to BCD
 	;
 	; This function converts a 16 bit binary value in A/Y into a 24 bit BCD. It
@@ -103,7 +105,7 @@ asmsub  uword2bcd  (uword value @ AY) -> clobbers(A,X) -> ()  {
 		sta  word2bcd_bcdbuff+0
 		sta  word2bcd_bcdbuff+1
 		sta  word2bcd_bcdbuff+2
-		ldx  #16			; the number of source bits
+		ldy  #16			; the number of source bits
 
 -		asl  c64.SCRATCH_ZPB1		; shift out one bit
 		rol  c64.SCRATCH_ZPREG
@@ -116,7 +118,7 @@ asmsub  uword2bcd  (uword value @ AY) -> clobbers(A,X) -> ()  {
 		lda  word2bcd_bcdbuff+2		; ... thru whole result
 		adc  word2bcd_bcdbuff+2
 		sta  word2bcd_bcdbuff+2
-		dex				; and repeat for next bit
+		dey				; and repeat for next bit
 		bne  -
 		cld				; back to binary
 		cli				; enable interrupts again
@@ -126,7 +128,7 @@ asmsub  uword2bcd  (uword value @ AY) -> clobbers(A,X) -> ()  {
 
 
 		ubyte[5]  word2decimal_output = 0
-asmsub  uword2decimal  (uword value @ AY) -> clobbers(A,X,Y) -> ()  {
+asmsub  uword2decimal  (uword value @ AY) -> clobbers(A,Y) -> ()  {
 	; ---- convert 16 bit uword in A/Y into decimal string into memory  'word2decimal_output'
 	%asm {{
 		jsr  uword2bcd
@@ -471,11 +473,12 @@ _loop		sta  c64.Colors,y
 }
 
 
-asmsub scroll_left_full  (ubyte alsocolors @ Pc) -> clobbers(A, X, Y) -> ()  {
+asmsub scroll_left_full  (ubyte alsocolors @ Pc) -> clobbers(A, Y) -> ()  {
 	; ---- scroll the whole screen 1 character to the left
 	;      contents of the rightmost column are unchanged, you should clear/refill this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
+		stx  c64.SCRATCH_ZPREGX
 		bcs  +
 		jmp  _scroll_screen
 
@@ -525,16 +528,18 @@ _scroll_screen  ; scroll the screen memory
 		dey
 		bpl  -
 
+		ldx  c64.SCRATCH_ZPREGX
 		rts
 	}}
 }
 
 
-asmsub scroll_right_full  (ubyte alsocolors @ Pc) -> clobbers(A,X) -> ()  {
+asmsub scroll_right_full  (ubyte alsocolors @ Pc) -> clobbers(A) -> ()  {
 	; ---- scroll the whole screen 1 character to the right
 	;      contents of the leftmost column are unchanged, you should clear/refill this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
+		stx  c64.SCRATCH_ZPREGX
 		bcs  +
 		jmp  _scroll_screen
 
@@ -576,16 +581,18 @@ _scroll_screen  ; scroll the screen memory
 		dex
 		bpl  -
 
+		ldx  c64.SCRATCH_ZPREGX
 		rts
 	}}
 }
 
 
-asmsub scroll_up_full  (ubyte alsocolors @ Pc) -> clobbers(A,X) -> ()  {
+asmsub scroll_up_full  (ubyte alsocolors @ Pc) -> clobbers(A) -> ()  {
 	; ---- scroll the whole screen 1 character up
 	;      contents of the bottom row are unchanged, you should refill/clear this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
+		stx  c64.SCRATCH_ZPREGX
 		bcs  +
 		jmp  _scroll_screen
 
@@ -627,16 +634,18 @@ _scroll_screen  ; scroll the screen memory
 		dex
 		bpl  -
 
+		ldx  c64.SCRATCH_ZPREGX
 		rts
 	}}
 }
 
 
-asmsub scroll_down_full  (ubyte alsocolors @ Pc) -> clobbers(A,X) -> ()  {
+asmsub scroll_down_full  (ubyte alsocolors @ Pc) -> clobbers(A) -> ()  {
 	; ---- scroll the whole screen 1 character down
 	;      contents of the top row are unchanged, you should refill/clear this yourself
 	;      Carry flag determines if screen color data must be scrolled too
 	%asm {{
+		stx  c64.SCRATCH_ZPREGX
 		bcs  +
 		jmp  _scroll_screen
 
@@ -678,6 +687,7 @@ _scroll_screen  ; scroll the screen memory
 		dex
 		bpl  -
 
+		ldx  c64.SCRATCH_ZPREGX
 		rts
 	}}
 }
@@ -703,11 +713,12 @@ asmsub  print (str text @ AY) -> clobbers(A,Y) -> ()  {
 }
 
 
-asmsub  print_p  (str_p text @ AY) -> clobbers(A,X) -> (ubyte @ Y)  {
+asmsub  print_p  (str_p text @ AY) -> clobbers(A) -> (ubyte @ Y)  {
 	; ---- print pstring (length as first byte) from A/Y, returns str len in Y
 	%asm {{
 		sta  c64.SCRATCH_ZPB1
 		sty  c64.SCRATCH_ZPREG
+		stx  c64.SCRATCH_ZPREGX
 		ldy  #0
 		lda  (c64.SCRATCH_ZPB1),y
 		beq  +
@@ -717,14 +728,16 @@ asmsub  print_p  (str_p text @ AY) -> clobbers(A,X) -> (ubyte @ Y)  {
 		jsr  c64.CHROUT
 		dex
 		bne  -
-+		rts 			; output string length is in Y
++		ldx  c64.SCRATCH_ZPREGX
+		rts 		; output string length is in Y
 	}}
 }
 
 
-asmsub  print_ub0  (ubyte value @ A) -> clobbers(A,X,Y) -> ()  {
+asmsub  print_ub0  (ubyte value @ A) -> clobbers(A,Y) -> ()  {
 	; ---- print the ubyte in A in decimal form, with left padding 0s (3 positions total)
 	%asm {{
+		stx  c64.SCRATCH_ZPREGX
 		jsr  c64utils.ubyte2decimal
 		pha
 		tya
@@ -732,14 +745,17 @@ asmsub  print_ub0  (ubyte value @ A) -> clobbers(A,X,Y) -> ()  {
 		txa
 		jsr  c64.CHROUT
 		pla
-		jmp  c64.CHROUT
+		jsr  c64.CHROUT
+		ldx  c64.SCRATCH_ZPREGX
+		rts
 	}}
 }
 
 
-asmsub  print_ub  (ubyte value @ A) -> clobbers(A,X,Y) -> ()  {
+asmsub  print_ub  (ubyte value @ A) -> clobbers(A,Y) -> ()  {
 	; ---- print the ubyte in A in decimal form, without left padding 0s
 	%asm {{
+		stx  c64.SCRATCH_ZPREGX
 		jsr  c64utils.ubyte2decimal
 _print_byte_digits
 		pha
@@ -754,13 +770,16 @@ _print_hundreds	tya
 _print_tens	txa
 		jsr  c64.CHROUT
 		pla
-		jmp  c64.CHROUT
+		jsr  c64.CHROUT
+		ldx  c64.SCRATCH_ZPREGX
+		rts
 	}}
 }
 
-asmsub  print_b  (byte value @ A) -> clobbers(A,X,Y) -> ()  {
+asmsub  print_b  (byte value @ A) -> clobbers(A,Y) -> ()  {
 	; ---- print the byte in A in decimal form, without left padding 0s
 	%asm {{
+		stx  c64.SCRATCH_ZPREGX
 		pha
 		cmp  #0
 		bpl  +
@@ -768,14 +787,17 @@ asmsub  print_b  (byte value @ A) -> clobbers(A,X,Y) -> ()  {
 		jsr  c64.CHROUT
 +		pla
 		jsr  c64utils.byte2decimal
-		jmp  print_ub._print_byte_digits
+		jsr  print_ub._print_byte_digits
+		ldx  c64.SCRATCH_ZPREGX
+		rts
 	}}
 }
 
 
-asmsub  print_ubhex  (ubyte prefix @ Pc, ubyte value @ A) -> clobbers(A,X,Y) -> ()  {
+asmsub  print_ubhex  (ubyte prefix @ Pc, ubyte value @ A) -> clobbers(A,Y) -> ()  {
 	; ---- print the ubyte in A in hex form (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
+		stx  c64.SCRATCH_ZPREGX
 		bcc  +
 		pha
 		lda  #'$'
@@ -784,14 +806,17 @@ asmsub  print_ubhex  (ubyte prefix @ Pc, ubyte value @ A) -> clobbers(A,X,Y) ->
 +		jsr  c64utils.ubyte2hex
 		jsr  c64.CHROUT
 		tya
-		jmp  c64.CHROUT
+		jsr  c64.CHROUT
+		ldx  c64.SCRATCH_ZPREGX
+		rts
 	}}
 }
 
 
-asmsub  print_ubbin  (ubyte prefix @ Pc, ubyte value @ A) -> clobbers(A,X,Y) ->()  {
+asmsub  print_ubbin  (ubyte prefix @ Pc, ubyte value @ A) -> clobbers(A,Y) ->()  {
 	; ---- print the ubyte in A in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
+		stx  c64.SCRATCH_ZPREGX
 		sta  c64.SCRATCH_ZPB1
 		bcc  +
 		lda  #'%'
@@ -804,12 +829,13 @@ asmsub  print_ubbin  (ubyte prefix @ Pc, ubyte value @ A) -> clobbers(A,X,Y) ->(
 +		jsr  c64.CHROUT
 		dey
 		bne  -
+		ldx  c64.SCRATCH_ZPREGX
 		rts
 	}}
 }
 
 
-asmsub  print_uwbin  (ubyte prefix @ Pc, uword value @ AY) -> clobbers(A,X,Y) ->()  {
+asmsub  print_uwbin  (ubyte prefix @ Pc, uword value @ AY) -> clobbers(A,Y) ->()  {
 	; ---- print the uword in A/Y in binary form (if Carry is set, a radix prefix '%' is printed as well)
 	%asm {{
 		pha
@@ -822,7 +848,7 @@ asmsub  print_uwbin  (ubyte prefix @ Pc, uword value @ AY) -> clobbers(A,X,Y) ->
 }
 
 
-asmsub print_uwhex  (ubyte prefix @ Pc, uword value @ AY) -> clobbers(A,X,Y) -> ()  {
+asmsub print_uwhex  (ubyte prefix @ Pc, uword value @ AY) -> clobbers(A,Y) -> ()  {
 	; ---- print the uword in A/Y in hexadecimal form (4 digits)
 	;      (if Carry is set, a radix prefix '$' is printed as well)
 	%asm {{
@@ -836,7 +862,7 @@ asmsub print_uwhex  (ubyte prefix @ Pc, uword value @ AY) -> clobbers(A,X,Y) ->
 }
 
 
-asmsub  print_uw0  (uword value @ AY) -> clobbers(A,X,Y) -> ()  {
+asmsub  print_uw0  (uword value @ AY) -> clobbers(A,Y) -> ()  {
 	; ---- print the uword in A/Y in decimal form, with left padding 0s (5 positions total)
 	%asm {{
 		jsr  c64utils.uword2decimal
@@ -851,7 +877,7 @@ asmsub  print_uw0  (uword value @ AY) -> clobbers(A,X,Y) -> ()  {
 }
 
 
-asmsub  print_uw  (uword value @ AY) -> clobbers(A,X,Y) -> ()  {
+asmsub  print_uw  (uword value @ AY) -> clobbers(A,Y) -> ()  {
 	; ---- print the uword in A/Y in decimal form, without left padding 0s
 	%asm {{
 		jsr  c64utils.uword2decimal
@@ -883,7 +909,7 @@ _pr_decimal
 	}}
 }
 
-asmsub  print_w  (word value @ AY) -> clobbers(A,X,Y) -> ()  {
+asmsub  print_w  (word value @ AY) -> clobbers(A,Y) -> ()  {
 	; ---- print the (signed) word in A/Y in decimal form, without left padding 0s
 	%asm {{
 		cpy  #0
@@ -904,7 +930,7 @@ asmsub  print_w  (word value @ AY) -> clobbers(A,X,Y) -> ()  {
 	}}
 }
 
-asmsub  input_chars  (uword buffer @ AY) -> clobbers(A, X) -> (ubyte @ Y)  {
+asmsub  input_chars  (uword buffer @ AY) -> clobbers(A) -> (ubyte @ Y)  {
 	; ---- Input a string (max. 80 chars) from the keyboard. Returns length in Y.
 	;      It assumes the keyboard is selected as I/O channel!
 

compiler/src/prog8/CompilerMain.kt

@@ -88,7 +88,7 @@ private fun compileMain(args: Array<String>) {
             }
             //println(" time2: $time2")
             val time3 = measureTimeMillis {
-                StatementReorderer(namespace, heap).process(moduleAst)     // reorder statements to please the compiler later
+                moduleAst.reorderStatements(namespace,heap)     // reorder statements to please the compiler later
             }
             //println(" time3: $time3")
             val time4 = measureTimeMillis {

compiler/src/prog8/ast/AST.kt

@@ -692,7 +692,7 @@ class VarDecl(val type: VarDeclType,
         return "VarDecl(name=$name, vartype=$type, datatype=$datatype, value=$value, pos=$position)"
     }
 
-    fun asDefaultValueDecl(): VarDecl {
+    fun asDefaultValueDecl(parent: Node?): VarDecl {
         val constValue = when(declaredDatatype) {
             DataType.UBYTE -> LiteralValue(DataType.UBYTE, 0, position=position)
             DataType.BYTE -> LiteralValue(DataType.BYTE, 0, position=position)
@@ -701,7 +701,10 @@ class VarDecl(val type: VarDeclType,
             DataType.FLOAT -> LiteralValue(DataType.FLOAT, floatvalue=0.0, position=position)
             else -> throw FatalAstException("can only set a default value for a numeric type")
         }
-        return VarDecl(type, declaredDatatype, arrayspec, name, constValue, position)
+        val decl = VarDecl(type, declaredDatatype, arrayspec, name, constValue, position)
+        if(parent!=null)
+            decl.linkParents(parent)
+        return decl
     }
 }
 

compiler/src/prog8/ast/AstChecker.kt

@@ -46,7 +46,7 @@ fun printWarning(msg: String, position: Position, detailInfo: String?=null) {
 }
 
 
-class AstChecker(private val namespace: INameScope,
+private class AstChecker(private val namespace: INameScope,
                  private val compilerOptions: CompilationOptions,
                  private val heap: HeapValues) : IAstProcessor {
     private val checkResult: MutableList<AstException> = mutableListOf()

compiler/src/prog8/ast/AstIdentifiersChecker.kt

@@ -40,7 +40,7 @@ fun Module.checkIdentifiers(heap: HeapValues): MutableMap<String, IStatement> {
 }
 
 
-class AstIdentifiersChecker(val heap: HeapValues) : IAstProcessor {
+private class AstIdentifiersChecker(val heap: HeapValues) : IAstProcessor {
     private val checkResult: MutableList<AstException> = mutableListOf()
 
     var symbols: MutableMap<String, IStatement> = mutableMapOf()

compiler/src/prog8/ast/AstRecursionChecker.kt

@@ -11,7 +11,7 @@ fun Module.checkRecursion(namespace: INameScope) {
 }
 
 
-class DirectedGraph<VT> {
+private class DirectedGraph<VT> {
     private val graph = mutableMapOf<VT, MutableSet<VT>>()
     private var uniqueVertices = mutableSetOf<VT>()
     val numVertices : Int
@@ -81,7 +81,7 @@ class DirectedGraph<VT> {
 }
 
 
-class AstRecursionChecker(private val namespace: INameScope) : IAstProcessor {
+private class AstRecursionChecker(private val namespace: INameScope) : IAstProcessor {
     private val callGraph = DirectedGraph<INameScope>()
 
     fun result(): List<AstException> {

compiler/src/prog8/ast/ImportedAstChecker.kt

@@ -13,7 +13,7 @@ fun Module.checkImportedValid() {
 }
 
 
-class ImportedAstChecker : IAstProcessor {
+private class ImportedAstChecker : IAstProcessor {
     private val checkResult: MutableList<SyntaxError> = mutableListOf()
 
     fun result(): List<SyntaxError> {

compiler/src/prog8/ast/StmtReorderer.kt

@@ -2,7 +2,15 @@ package prog8.ast
 
 import prog8.compiler.HeapValues
 
-class StatementReorderer(private val namespace: INameScope, private val heap: HeapValues): IAstProcessor {
+fun Module.reorderStatements(namespace: INameScope, heap: HeapValues) {
+    val initvalueCreator = VarInitValueCreator()
+    this.process(initvalueCreator)
+
+    val checker = StatementReorderer(namespace, heap)
+    this.process(checker)
+}
+
+private class StatementReorderer(private val namespace: INameScope, private val heap: HeapValues): IAstProcessor {
     // Reorders the statements in a way the compiler needs.
     // - 'main' block must be the very first statement UNLESS it has an address set.
     // - blocks are ordered by address, where blocks without address are put at the end.
@@ -14,9 +22,7 @@ class StatementReorderer(private val namespace: INameScope, private val heap: He
     // - the 'start' subroutine in the 'main' block will be moved to the top immediately following the directives.
     // - all other subroutines will be moved to the end of their block.
 
-
     private val directivesToMove = setOf("%output", "%launcher", "%zeropage", "%zpreserved", "%address", "%option")
-    private val vardeclsToAdd = mutableMapOf<INameScope, MutableList<VarDecl>>()
 
     override fun process(module: Module) {
         super.process(module)
@@ -37,14 +43,6 @@ class StatementReorderer(private val namespace: INameScope, private val heap: He
         module.statements.removeAll(directives)
         module.statements.addAll(0, directives)
 
-        // add any new vardecls
-        // @todo doing it this late causes problems with namespace lookups elsewhere in sortConstantAssignments
-        for(decl in vardeclsToAdd)
-            for(d in decl.value) {
-                d.linkParents(decl.key as Node)
-                decl.key.statements.add(0, d)
-            }
-
         sortConstantAssignments(module.statements)
     }
 
@@ -155,7 +153,7 @@ class StatementReorderer(private val namespace: INameScope, private val heap: He
     }
 
     private fun sortConstantAssignmentSequence(first: Assignment, stmtIter: MutableIterator<IStatement>): Pair<List<Assignment>, IStatement?> {
-        val sequence= mutableListOf<Assignment>(first)
+        val sequence= mutableListOf(first)
         var trailing: IStatement? = null
         while(stmtIter.hasNext()) {
             val next = stmtIter.next()
@@ -176,20 +174,40 @@ class StatementReorderer(private val namespace: INameScope, private val heap: He
         return Pair(sorted, trailing)
     }
 
+}
+
+
+private class VarInitValueCreator: IAstProcessor {
+    // Replace the var decl with an assignment and add a new vardecl with the default constant value.
+    // This makes sure the variables get reset to the intended value on a next run of the program.
+    // Variable decls without a value don't get this treatment, which means they retain the last
+    // value they had when restarting the program.
+    // This is done in a separate step because it interferes with the namespace lookup of symbols
+    // in other ast processors.
+
+    private val vardeclsToAdd = mutableMapOf<INameScope, MutableList<VarDecl>>()
+
+    override fun process(module: Module) {
+        super.process(module)
+
+        // add any new vardecls to the various scopes
+        for(decl in vardeclsToAdd)
+            for(d in decl.value) {
+                d.linkParents(decl.key as Node)
+                decl.key.statements.add(0, d)
+            }
+    }
+
     override fun process(decl: VarDecl): IStatement {
         super.process(decl)
         if(decl.type!=VarDeclType.VAR || decl.value==null)
             return decl
 
-        // Replace the var decl with an assignment and add a new vardecl with the default constant value.
-        // This makes sure the variables get reset to the intended value on a next run of the program.
-        // Variable decls without a value don't get this treatment, which means they retain the last
-        // value they had when restarting the program.
         if(decl.datatype in NumericDatatypes) {
             val scope = decl.definingScope()
             if(scope !in vardeclsToAdd)
                 vardeclsToAdd[scope] = mutableListOf()
-            vardeclsToAdd[scope]!!.add(decl.asDefaultValueDecl())
+            vardeclsToAdd[scope]!!.add(decl.asDefaultValueDecl(null))
             val declvalue = decl.value!!
             val value =
                     if(declvalue is LiteralValue) {
@@ -207,4 +225,5 @@ class StatementReorderer(private val namespace: INameScope, private val heap: He
         }
         return decl
     }
+
 }