Allow array at label expressions

Author: boriel

libzxbc/zxbparser.py

@@ -682,7 +682,7 @@ def p_var_decl_at(p):
                 entry.make_alias(tmp.operand)
                 entry.offset = tmp.operand.offset
             else:
-                error(p.lineno(4), 'Only address of identifiers are allowed')
+                error(p.lineno(4), 'Only addresses of identifiers are allowed')
                 return
         else:
             entry.addr = tmp
@@ -765,9 +765,18 @@ def p_arr_decl_attr(p):
         p[0] = None
         return
 
-    if not is_number(expr):
-        api.errmsg.syntax_error_address_must_be_constant(p.lineno(2))
-        p[0] = None
+    if expr.token == 'CONST':
+        expr = expr.expr
+        if expr.token == 'UNARY' and expr.operator == 'ADDRESS':  # Must be an ID
+            if expr.operand.token == 'ARRAYACCESS':
+                if expr.operand.offset is None:
+                    error(p.lineno(4), 'Address is not constant. Only constant subscripts are allowed')
+                    return
+            elif expr.operand.token not in ('VAR', 'LABEL'):
+                error(p.lineno(3), 'Only addresses of identifiers are allowed')
+                return
+    elif not is_number(expr):
+        api.errmsg.syntax_error_address_must_be_constant(p.lineno(3))
         return
 
     arr_entry = SYMBOL_TABLE.access_array(arr_decl[0], arr_decl[1])

tests/functional/dim_arr_at_label0.asm

@@ -0,0 +1,43 @@
+	org 32768
+__START_PROGRAM:
+	di
+	push ix
+	push iy
+	exx
+	push hl
+	exx
+	ld hl, 0
+	add hl, sp
+	ld (__CALL_BACK__), hl
+	ei
+__LABEL__c:
+	ld hl, 0
+	ld b, h
+	ld c, l
+__END_PROGRAM:
+	di
+	ld hl, (__CALL_BACK__)
+	ld sp, hl
+	exx
+	pop hl
+	exx
+	pop iy
+	pop ix
+	ei
+	ret
+__CALL_BACK__:
+	DEFW 0
+ZXBASIC_USER_DATA:
+	_a.__DATA__ EQU ADDRESS(c)
+_a:
+	DEFW __LABEL0
+_a.__DATA__.__PTR__:
+	DEFW __LABEL__c
+__LABEL0:
+	DEFW 0000h
+	DEFB 01h
+; Defines DATA END --> HEAP size is 0
+ZXBASIC_USER_DATA_END:
+	; Defines USER DATA Length in bytes
+ZXBASIC_USER_DATA_LEN EQU ZXBASIC_USER_DATA_END - ZXBASIC_USER_DATA
+	END

tests/functional/dim_arr_at_label0.bas

@@ -0,0 +1,6 @@
+REM arrat at label
+DIM a(5) as Ubyte AT @c
+
+c:
+
+

tests/functional/dim_arr_at_label1.asm

@@ -0,0 +1,43 @@
+	org 32768
+__START_PROGRAM:
+	di
+	push ix
+	push iy
+	exx
+	push hl
+	exx
+	ld hl, 0
+	add hl, sp
+	ld (__CALL_BACK__), hl
+	ei
+__LABEL__c:
+	ld hl, 0
+	ld b, h
+	ld c, l
+__END_PROGRAM:
+	di
+	ld hl, (__CALL_BACK__)
+	ld sp, hl
+	exx
+	pop hl
+	exx
+	pop iy
+	pop ix
+	ei
+	ret
+__CALL_BACK__:
+	DEFW 0
+ZXBASIC_USER_DATA:
+	_a.__DATA__ EQU ADDRESS(c) PLUS 1
+_a:
+	DEFW __LABEL0
+_a.__DATA__.__PTR__:
+	DEFW (__LABEL__c) + (1)
+__LABEL0:
+	DEFW 0000h
+	DEFB 01h
+; Defines DATA END --> HEAP size is 0
+ZXBASIC_USER_DATA_END:
+	; Defines USER DATA Length in bytes
+ZXBASIC_USER_DATA_LEN EQU ZXBASIC_USER_DATA_END - ZXBASIC_USER_DATA
+	END

tests/functional/dim_arr_at_label1.bas

@@ -0,0 +1,6 @@
+REM Array elements at label c + 1
+DIM a(5) as Ubyte AT @c + 1
+
+c:
+
+