fix some errors

il65/compile.py

@@ -32,7 +32,7 @@ class PlyParser:
         module = None
         try:
             module = parse_file(filename, self.lexer_error)
-            self.check_directives(module)
+            self.check_directives_and_const_defs(module)
             self.apply_directive_options(module)
             module.scope.define_builtin_functions()
             self.process_imports(module)
@@ -44,7 +44,7 @@ class PlyParser:
                 self.determine_subroutine_usage(module)
                 self.all_parents_connected(module)
                 cf = ConstantFold(module)
-                cf.fold_constants()   # do some constant-folding
+                cf.fold_constants()
                 self.semantic_check(module)
                 self.coerce_values(module)
                 self.check_floats_enabled(module)
@@ -430,10 +430,13 @@ class PlyParser:
                                 namespace, name = name.rsplit(".", maxsplit=2)
                             usages[(namespace, symbol.name)].add(str(asmnode.sourceref))
 
-    def check_directives(self, module: Module) -> None:
+    def check_directives_and_const_defs(self, module: Module) -> None:
         imports = set()  # type: Set[str]
         for node in module.all_nodes():
-            if isinstance(node, Directive):
+            if isinstance(node, VarDef):
+                if node.value is None and node.vartype == VarType.CONST:
+                    raise ParseError("const should be initialized with a compile-time constant value", node.sourceref)
+            elif isinstance(node, Directive):
                 assert isinstance(node.parent, Scope)
                 if node.parent.level == "module":
                     if node.name not in {"output", "zp", "address", "import", "saveregisters", "noreturn"}:

il65/constantfold.py

@@ -42,7 +42,10 @@ class ConstantFold:
                 self._constant_folding()
 
     def _constant_folding(self) -> None:
-        for expression in self.module.all_nodes(Expression):
+        for expression in list(self.module.all_nodes(Expression)):
+            if expression.parent is None or expression.parent.parent is None:
+                # stale expression node (was part of an expression that was constant-folded away)
+                continue
             if isinstance(expression, LiteralValue):
                 continue
             try:

il65/plyparse.py

@@ -22,7 +22,7 @@ __all__ = ["ProgramFormat", "ZpOptions", "math_functions", "builtin_functions",
            "UndefinedSymbolError", "AstNode", "Directive", "Scope", "Block", "Module", "Label", "Expression",
            "Register", "Subroutine", "LiteralValue", "AddressOf", "SymbolName", "Dereference", "IncrDecr",
            "ExpressionWithOperator", "Goto", "SubCall", "VarDef", "Return", "Assignment", "AugAssignment",
-           "InlineAssembly", "AssignmentTargets",
+           "InlineAssembly", "AssignmentTargets", "BuiltinFunction", "TokenFilter", "parser", "connect_parents",
            "parse_file", "coerce_constant_value", "datatype_of", "check_symbol_definition"]
 
 
@@ -108,6 +108,7 @@ class AstNode:
         self.nodes[idx] = newnode
         newnode.parent = self
         oldnode.parent = None
+        oldnode.nodes = None
 
     def add_node(self, newnode: 'AstNode', index: int = None) -> None:
         assert isinstance(newnode, AstNode)
@@ -804,8 +805,10 @@ class VarDef(AstNode):
         if self.datatype.isarray() and sum(self.size) in (0, 1):
             print("warning: {}: array/matrix with size 1, use normal byte/word instead".format(self.sourceref))
         if self.value is None and (self.datatype.isnumeric() or self.datatype.isarray()):
-            self.value = LiteralValue(value=0, sourceref=self.sourceref)
-            self.value.parent = self
+            if self.vartype != VarType.CONST:
+                # leave None when it's a const, so we can check for uninitialized consts later and raise error.
+                self.value = LiteralValue(value=0, sourceref=self.sourceref)
+                self.value.parent = self
         # if it's a matrix with interleave, it must be memory mapped
         if self.datatype == DataType.MATRIX and len(self.size) == 3:
             if self.vartype != VarType.MEMORY:

tests/test_parser.py

@@ -1,10 +1,9 @@
 import math
 import pytest
 from il65.plylex import lexer, tokens, find_tok_column, literals, reserved, SourceRef
-from il65.plyparse import parser, connect_parents, TokenFilter, Module, Subroutine, Block, IncrDecr, Scope, \
-    AstNode, Expression, Assignment, VarDef, Register, ExpressionWithOperator, LiteralValue, Label, SubCall, Dereference,\
-    BuiltinFunction, UndefinedSymbolError
+from il65.plyparse import *
 from il65.datatypes import DataType, VarType
+from il65.constantfold import ConstantFold
 
 
 def lexer_error(sourceref: SourceRef, fmtstring: str, *args: str) -> None:
@@ -450,3 +449,49 @@ def test_const_other_expressions():
     assert not e[2].is_compile_constant()
     with pytest.raises(TypeError):
         e[2].const_value()
+
+
+def test_vdef_const_folds():
+    src = """
+~ {
+    const  cb1 = 123
+    const  cb2 = cb1
+    const  cb3 = cb1*3
+}
+"""
+    result = parse_source(src)
+    if isinstance(result, Module):
+        result.scope.define_builtin_functions()
+    vd = list(result.all_nodes(VarDef))
+    assert vd[0].name == "cb1"
+    assert vd[0].vartype == VarType.CONST
+    assert vd[0].datatype == DataType.BYTE
+    assert isinstance(vd[0].value, LiteralValue)
+    assert vd[0].value.value == 123
+    assert vd[1].name == "cb2"
+    assert vd[1].vartype == VarType.CONST
+    assert vd[1].datatype == DataType.BYTE
+    assert isinstance(vd[1].value, SymbolName)
+    assert vd[1].value.name == "cb1"
+    assert vd[2].name == "cb3"
+    assert vd[2].vartype == VarType.CONST
+    assert vd[2].datatype == DataType.BYTE
+    assert isinstance(vd[2].value, ExpressionWithOperator)
+    cf = ConstantFold(result)
+    cf.fold_constants()
+    vd = list(result.all_nodes(VarDef))
+    assert vd[0].name == "cb1"
+    assert vd[0].vartype == VarType.CONST
+    assert vd[0].datatype == DataType.BYTE
+    assert isinstance(vd[0].value, LiteralValue)
+    assert vd[0].value.value == 123
+    assert vd[1].name == "cb2"
+    assert vd[1].vartype == VarType.CONST
+    assert vd[1].datatype == DataType.BYTE
+    assert isinstance(vd[1].value, LiteralValue)
+    assert vd[1].value.value == 123
+    assert vd[2].name == "cb3"
+    assert vd[2].vartype == VarType.CONST
+    assert vd[2].datatype == DataType.BYTE
+    assert isinstance(vd[2].value, LiteralValue)
+    assert vd[2].value.value == 369

tests/test_vardef.py

@@ -18,8 +18,7 @@ def test_creation():
     assert v.vartype == VarType.CONST
     assert v.datatype == DataType.BYTE
     assert v.size == [1]
-    assert isinstance(v.value, LiteralValue)
-    assert v.value.value == 0
+    assert v.value is None
     assert v.zp_address is None
     v = VarDef(name="v2", vartype="memory", datatype=None, sourceref=sref)
     assert v.vartype == VarType.MEMORY
@@ -88,11 +87,13 @@ def test_const_value():
     with pytest.raises(TypeError):
         v.const_value()
     v = VarDef(name="v1", vartype="const", datatype=DatatypeNode(name="word", sourceref=sref), sourceref=sref)
-    assert v.const_value() == 0
+    with pytest.raises(ValueError):
+        v.const_value()
     v.value = LiteralValue(value=42, sourceref=sref)
     assert v.const_value() == 42
     v = VarDef(name="v1", vartype="const", datatype=DatatypeNode(name="float", sourceref=sref), sourceref=sref)
-    assert v.const_value() == 0
+    with pytest.raises(ValueError):
+        v.const_value()
     v.value = LiteralValue(value=42.9988, sourceref=sref)
     assert v.const_value() == 42.9988
     e = ExpressionWithOperator(operator="-", sourceref=sref)

todo.ill

@@ -1,9 +1,6 @@
 ~ main {
-
 	var .float flt = -9.87e-21
 	const .word border = $0099
-	const        cbyte2         = 2222
-	const        cbyte2b        = cbyte2*3          ; @todo fix scope not found crash
 	var counter = 1
 
 start:
@@ -33,7 +30,6 @@ start:
 	block2.start()
 	return 44.123
 
-sub varssub()->() {
 sub goodbye ()->() {
         var xxxxxx             ; @todo vars in sub?
         memory y = $c000        ; @todo memvars in sub?
@@ -43,7 +39,7 @@ sub goodbye ()->() {
         return
 }
 
-}
+
 sub derp ()->() {
         const q = 22
 	A = q *4                ; @todo fix scope not found error