refactored symbol assignment (unfinished)

git-svn-id: https://svn.code.sf.net/p/acme-crossass/code-0/trunk@214 4df02467-bbd4-4a76-a152-e7ce94205b78

src/alu.c

@@ -351,7 +351,14 @@ static void get_symbol_value(scope_t scope, char optional_prefix_char, size_t na
 	struct object	*arg;
 
 	// if the symbol gets created now, mark it as unsure
-	symbol = symbol_find(scope, NUMBER_EVER_UNDEFINED);	// TODO - split into "find" and "if NULL object, make into undefined int"
+	symbol = symbol_find(scope);
+	if (symbol->object.type == NULL) {
+		// finish symbol item by making it an undefined int
+		symbol->object.type = &type_int;
+		symbol->object.u.number.flags = NUMBER_EVER_UNDEFINED;
+		symbol->object.u.number.addr_refs = 0;
+		symbol->object.u.number.val.intval = 0;
+	}
 	// first push on arg stack, so we have a local copy we can "unpseudopc"
 	arg = &arg_stack[arg_sp++];
 	*arg = symbol->object;

src/global.c

@@ -168,16 +168,17 @@ static void set_label(scope_t scope, int stat_flags, int force_bit, boolean chan
 	struct object	result;
 	struct symbol	*symbol;
 
-	symbol = symbol_find(scope, force_bit);	// TODO - split into "find", "forcebit handling", "if NULL object, make int" and "if not int, complain"
-	// label definition
 	if ((stat_flags & SF_FOUND_BLANK) && config.warn_on_indented_labels)
 		Throw_first_pass_warning("Label name not in leftmost column.");
+	symbol = symbol_find(scope);
+	// label definition
 	vcpu_read_pc(&pc);
 	// FIXME - if undefined, check pass.complain_about_undefined and maybe throw "value not defined"!
 	result.type = &type_int;
 	result.u.number.flags = pc.flags & NUMBER_IS_DEFINED;
 	result.u.number.val.intval = pc.val.intval;
 	result.u.number.addr_refs = pc.addr_refs;
+	symbol_forcebit(symbol, force_bit);	// TODO - "if NULL object, make int" and "if not int, complain"
 	symbol_set_object(symbol, &result, change_allowed);	// FIXME - "backward anon allows number redef" is different from "!set allows object redef"!
 	symbol->pseudopc = pseudopc_get_context();
 	// global labels must open new scope for cheap locals
@@ -186,29 +187,55 @@ static void set_label(scope_t scope, int stat_flags, int force_bit, boolean chan
 }
 
 
+// call with symbol name in GlobalDynaBuf and GotByte == '='
+// "po_set" is for "!set" pseudo opcode, so changes are allowed
+void parse_assignment(scope_t scope, int force_bit, boolean po_set)
+{
+	struct symbol	*symbol;
+	struct object	result;
+
+	GetByte();	// eat '='
+	symbol = symbol_find(scope);
+	ALU_any_result(&result);
+	// if wanted, mark as address reference
+	if (typesystem_says_address()) {
+		// FIXME - checking types explicitly is ugly...
+		if ((result.type == &type_int)
+		|| (result.type == &type_float))
+			result.u.number.addr_refs = 1;
+	}
+	// FIXME - force bit can only be used if result is number! check!
+	symbol_forcebit(symbol, force_bit);
+	// if this was called by !set, new force bit replaces old one:
+	if (po_set) {
+		// clear symbol's force bits and set new ones
+		// (but only do this for numbers!)
+		if (((symbol->object.type == &type_int) || (symbol->object.type == &type_float))
+		&& ((result.type == &type_int) || (result.type == &type_float))) {
+			symbol->object.u.number.flags &= ~(NUMBER_FORCEBITS | NUMBER_FITS_BYTE);
+			if (force_bit) {
+				symbol->object.u.number.flags |= force_bit;
+				result.u.number.flags &= ~(NUMBER_FORCEBITS | NUMBER_FITS_BYTE);
+			}
+		}
+		// FIXME - take a good look at the flags handling above and in the fn called below and clean this up!
+	}
+	symbol_set_object(symbol, &result, po_set);
+}
+
+
 // parse symbol definition (can be either global or local, may turn out to be a label).
 // name must be held in GlobalDynaBuf.
 static void parse_symbol_definition(scope_t scope, int stat_flags)
 {
 	struct object	result;
 	struct symbol	*symbol;
-	int		force_bit	= Input_get_force_bit();	// skips spaces after
-	// FIXME - force bit is allowed for label definitions?!
+	int		force_bit;
 
+	force_bit = Input_get_force_bit();	// skips spaces after	(yes, force bit is allowed for label definitions)
 	if (GotByte == '=') {
 		// explicit symbol definition (symbol = <something>)
-		symbol = symbol_find(scope, force_bit);	// FIXME - split into "find", "forcebit handling", "if not NULL object, types must be equal"...
-		// symbol = parsed value
-		GetByte();	// skip '='
-		ALU_any_result(&result);
-		// if wanted, mark as address reference
-		if (typesystem_says_address()) {
-			// FIXME - checking types explicitly is ugly...
-			if ((result.type == &type_int)
-			|| (result.type == &type_float))
-				result.u.number.addr_refs = 1;
-		}
-		symbol_set_object(symbol, &result, FALSE);
+		parse_assignment(scope, force_bit, FALSE);
 		Input_ensure_EOS();
 	} else {
 		// implicit symbol definition (label)
@@ -220,8 +247,11 @@ static void parse_symbol_definition(scope_t scope, int stat_flags)
 // Parse global symbol definition or assembler mnemonic
 static void parse_mnemo_or_global_symbol_def(int *statement_flags)
 {
+	boolean	is_mnemonic;
+
+	is_mnemonic = CPU_state.type->keyword_is_mnemonic(Input_read_keyword());
 	// It is only a label if it isn't a mnemonic
-	if ((CPU_state.type->keyword_is_mnemonic(Input_read_keyword()) == FALSE)
+	if ((!is_mnemonic)
 	&& first_label_of_statement(statement_flags)) {
 		// Now GotByte = illegal char
 		// 04 Jun 2005: this fix should help to explain "strange" error messages.
@@ -297,7 +327,7 @@ void Parse_until_eob_or_eof(void)
 		statement_flags = 0;	// no "label = pc" definition yet
 		typesystem_force_address_statement(FALSE);
 		// Parse until end of statement. Only loops if statement
-		// contains "label = pc" definition and something else; or
+		// contains implicit label definition (=pc) and something else; or
 		// if "!ifdef/ifndef" is true/false, or if "!addr" is used without block.
 		do {
 			// check for pseudo opcodes was moved out of switch,

src/global.h

@@ -134,6 +134,9 @@ do {				\
 extern void config_default(struct config *conf);
 // allocate memory and die if not available
 extern void *safe_malloc(size_t amount);
+// call with symbol name in GlobalDynaBuf and GotByte == '='
+// "po_set" is for "!set" pseudo opcode, so changes are allowed
+extern void parse_assignment(scope_t scope, int force_bit, boolean po_set);
 // Parse block, beginning with next byte.
 // End reason (either CHAR_EOB or CHAR_EOF) can be found in GotByte afterwards
 // Has to be re-entrant.

src/macro.c

@@ -250,8 +250,8 @@ void Macro_parse_call(void)	// Now GotByte = dot or first char of macro name
 	// internal_name = MacroTitle ARG_SEPARATOR (grows to signature)
 	// Accept n>=0 comma-separated arguments before CHAR_EOS.
 	// Valid argument formats are:
-	// EXPRESSION (everything that does NOT start with '~'
-	// ~SYMBOL
+	//	~SYMBOL		call by ref
+	//	EXPRESSION	call by value (everything that does NOT start with '~')
 	// now GotByte = non-space
 	if (GotByte != CHAR_EOS) {	// any at all?
 		do {
@@ -263,10 +263,10 @@ void Macro_parse_call(void)	// Now GotByte = dot or first char of macro name
 			if (GotByte == REFERENCE_CHAR) {
 				// read call-by-reference arg
 				DynaBuf_append(internal_name, ARGTYPE_REF);
-				GetByte();	// skip '~' character
+				GetByte();	// eat '~'
 				Input_read_scope_and_keyword(&symbol_scope);
 				// GotByte = illegal char
-				arg_table[arg_count].symbol = symbol_find(symbol_scope, 0);	// FIXME - do not default to undefined int!
+				arg_table[arg_count].symbol = symbol_find(symbol_scope);	// CAUTION, object type may be NULL!
 			} else {
 				// read call-by-value arg
 				DynaBuf_append(internal_name, ARGTYPE_VALUE);
@@ -317,22 +317,21 @@ void Macro_parse_call(void)	// Now GotByte = dot or first char of macro name
 				// In both cases, GlobalDynaBuf may be used.
 				if (GotByte == REFERENCE_CHAR) {
 					// assign call-by-reference arg
-					GetByte();	// skip '~' character
+					GetByte();	// eat '~'
 					Input_read_scope_and_keyword(&symbol_scope);
 					// create new tree node and link existing symbol struct from arg list to it
 					if ((Tree_hard_scan(&symbol_node, symbols_forest, symbol_scope, TRUE) == FALSE)
 					&& (FIRST_PASS))
 						Throw_error("Macro parameter twice.");
-					symbol_node->body = arg_table[arg_count].symbol;
+					symbol_node->body = arg_table[arg_count].symbol;	// CAUTION, object type may be NULL
 				} else {
 					// assign call-by-value arg
 					Input_read_scope_and_keyword(&symbol_scope);
-					symbol = symbol_find(symbol_scope, 0);	// FIXME - split into "find", "ensure freshly created"
-// FIXME - add a possibility to symbol_find to make it possible to find out
-// whether symbol was just created. Then check for the same error message here
-// as above ("Macro parameter twice.").
+					symbol = symbol_find(symbol_scope);
+// FIXME - find out if symbol was just created.
+// Then check for the same error message here as above ("Macro parameter twice.").
 // TODO - on the other hand, this would rule out globals as args (stupid anyway, but not illegal yet!)
-					symbol->object = arg_table[arg_count].result;	// FIXME - this assignment redefines globals without throwing errors!
+					symbol->object = arg_table[arg_count].result;	// FIXME - this assignment redefines globals/whatever without throwing errors!
 				}
 				++arg_count;
 			} while (Input_accept_comma());

src/pseudoopcodes.c

@@ -739,37 +739,19 @@ Throw_serious_error("Not yet");	// FIXME
 // (re)set symbol
 static enum eos po_set(void)	// now GotByte = illegal char
 {
-	struct object	result;
-	int		force_bit;
-	struct symbol	*symbol;
-	scope_t		scope;
+	scope_t	scope;
+	int	force_bit;
 
 	if (Input_read_scope_and_keyword(&scope) == 0)	// skips spaces before
-		// now GotByte = illegal char
-		return SKIP_REMAINDER;
+		return SKIP_REMAINDER;	// zero length
 
 	force_bit = Input_get_force_bit();	// skips spaces after
-	symbol = symbol_find(scope, force_bit);	// FIXME - split into "find" and "handle forcebits", remove the "default to undefined int" part!
 	if (GotByte != '=') {
 		Throw_error(exception_syntax);
 		return SKIP_REMAINDER;
 	}
 
-	// symbol = parsed value
-	GetByte();	// proceed with next char
-	ALU_any_result(&result);
-	// clear symbol's force bits and set new ones
-	// (but only do this for numbers!)
-	if (((symbol->object.type == &type_int) || (symbol->object.type == &type_float))
-	&& ((result.type == &type_int) || (result.type == &type_float))) {
-		symbol->object.u.number.flags &= ~(NUMBER_FORCEBITS | NUMBER_FITS_BYTE);
-		if (force_bit) {
-			symbol->object.u.number.flags |= force_bit;
-			result.u.number.flags &= ~(NUMBER_FORCEBITS | NUMBER_FITS_BYTE);
-		}
-	}
-	// FIXME - take a good look at the flags handling above and in the fn called below and clean this up!
-	symbol_set_object(symbol, &result, TRUE);
+	parse_assignment(scope, force_bit, TRUE);
 	return ENSURE_EOS;
 }
 
@@ -1053,11 +1035,12 @@ static enum eos po_for(void)	// now GotByte = illegal char
 	struct for_loop	loop;
 
 	if (Input_read_scope_and_keyword(&scope) == 0)	// skips spaces before
-		return SKIP_REMAINDER;
+		return SKIP_REMAINDER;	// zero length
 
 	// now GotByte = illegal char
 	force_bit = Input_get_force_bit();	// skips spaces after
-	loop.symbol = symbol_find(scope, force_bit);	// FIXME - split into "find" and "handle force bit". if type is not NULL, complain if not number!
+	loop.symbol = symbol_find(scope);	// FIXME - if type is not NULL, complain if not number!
+	symbol_forcebit(loop.symbol, force_bit);
 	if (!Input_accept_comma()) {
 		Throw_error(exception_syntax);
 		return SKIP_REMAINDER;
@@ -1066,7 +1049,8 @@ static enum eos po_for(void)	// now GotByte = illegal char
 	ALU_defined_int(&intresult);	// read first argument
 	loop.counter.addr_refs = intresult.addr_refs;
 	if (Input_accept_comma()) {
-		loop.use_old_algo = FALSE;	// new format - yay!
+		// new format - yay!
+		loop.use_old_algo = FALSE;
 		if (config.wanted_version < VER_NEWFORSYNTAX)
 			Throw_first_pass_warning("Found new \"!for\" syntax.");
 		loop.counter.first = intresult.val.intval;	// use first argument
@@ -1079,7 +1063,8 @@ static enum eos po_for(void)	// now GotByte = illegal char
 		}
 		loop.counter.increment = (loop.counter.last < loop.counter.first) ? -1 : 1;
 	} else {
-		loop.use_old_algo = TRUE;	// old format - booo!
+		// old format - booo!
+		loop.use_old_algo = TRUE;
 		if (config.wanted_version >= VER_NEWFORSYNTAX)
 			Throw_first_pass_warning("Found old \"!for\" syntax.");
 		if (intresult.val.intval < 0)

src/symbol.c

@@ -107,8 +107,9 @@ static void dump_vice_unusednonaddress(struct rwnode *node, FILE *fd)
 }
 
 
-// temporary helper function to properly refactor this mess
-static struct symbol *temp_find(scope_t scope)
+// search for symbol. if it does not exist, create with NULL object (CAUTION!).
+// the symbol name must be held in GlobalDynaBuf.
+struct symbol *symbol_find(scope_t scope)
 {
 	struct rwnode	*node;
 	struct symbol	*symbol;
@@ -132,51 +133,27 @@ static struct symbol *temp_find(scope_t scope)
 	return symbol;	// now symbol->object.type can be tested to see if this was freshly created.
 	// CAUTION: this only works if caller always sets a type pointer after checking! if NULL is kept, the struct still looks new later on...
 }
-// search for symbol. create if nonexistant. if created, give it flags "flags".
-// the symbol name must be held in GlobalDynaBuf.
-/*
-FIXME - to get lists/strings to work, this can no longer create an int by default!
-maybe get rid of "int flags" and use some "struct object *default" instead?
-called by;
-alu.c
-	get_symbol_value (here it's okay to create an undefined int)
-global.c
-	set_label		implicit symbol definition (gets assigned pc, so int is ok)
-	parse_symbol_definition	explicit symbol definition
-macro.c
-	Macro_parse_call	early to build array of outer refs in case of call-by-ref
-	Macro_parse_call	later to lookup inner symbols in case of call-by-value
-symbol.c
-	symbol_define
-	symbol_fix_forward_anon_name
-*/
-struct symbol *symbol_find(scope_t scope, int flags)	// FIXME - "flags" is either 0 or UNDEFINED or a forcebit, right? move UNDEFINED and forcebit stuff elsewhere!
-{
-	struct symbol	*symbol;
-	int		new_force_bits;
 
-	symbol = temp_find(scope);
+
+// FIXME - merge with function below!
+void symbol_forcebit(struct symbol *symbol, int force_bit)
+{
 	// if symbol has no object assigned to it, make it an int
 	if (symbol->object.type == NULL) {
 		// finish empty symbol item
 		symbol->object.type = &type_int;
-		symbol->object.u.number.flags = flags;
+		symbol->object.u.number.flags = force_bit;
 		symbol->object.u.number.addr_refs = 0;
 		symbol->object.u.number.val.intval = 0;
 	} else {
 		// make sure the force bits don't clash
 		if ((symbol->object.type == &type_int)
 		|| (symbol->object.type == &type_float)) {
-			new_force_bits = flags & NUMBER_FORCEBITS;
-			if (new_force_bits)
-				if ((symbol->object.u.number.flags & NUMBER_FORCEBITS) != new_force_bits)
-					Throw_error("Too late for postfix.");
+			if ((symbol->object.u.number.flags & NUMBER_FORCEBITS) != force_bit)
+				Throw_error("Too late for postfix.");
 		}
 	}
-	return symbol;
 }
-
-
 // assign value to symbol. the function acts upon the symbol's flag bits and
 // produces an error if needed.
 // TODO - split checks into two parts: first deal with object type. in case of number, then check value/flags/whatever
@@ -237,8 +214,8 @@ void symbol_define(intval_t value)
 	result.type = &type_int;
 	result.u.number.flags = NUMBER_IS_DEFINED;
 	result.u.number.val.intval = value;
-	symbol = symbol_find(SCOPE_GLOBAL, 0);
-	symbol_set_object(symbol, &result, TRUE);
+	symbol = symbol_find(SCOPE_GLOBAL);
+	symbol->object = result;
 }
 
 
@@ -268,6 +245,12 @@ void symbols_vicelabels(FILE *fd)
 // references the *next* anonymous forward label definition. The tricky bit is,
 // each name length would need its own counter. But hey, ACME's real quick in
 // finding symbols, so I'll just abuse the symbol system to store those counters.
+// example:
+//	forward anon name is "+++"
+//	we look up that symbol's value in the current local scope -> $12
+//	we attach hex digits to name -> "+++21"
+//	that's the name of the symbol that _actually_ contains the address
+// caller sets "increment" to TRUE for writing, FALSE for reading
 void symbol_fix_forward_anon_name(boolean increment)
 {
 	struct symbol	*counter_symbol;
@@ -275,10 +258,17 @@ void symbol_fix_forward_anon_name(boolean increment)
 
 	// terminate name, find "counter" symbol and read value
 	DynaBuf_append(GlobalDynaBuf, '\0');
-	counter_symbol = symbol_find(section_now->local_scope, 0);
-	// sanity check: it must be an int!
-	if (counter_symbol->object.type != &type_int)
+	counter_symbol = symbol_find(section_now->local_scope);
+	if (counter_symbol->object.type == NULL) {
+		// finish freshly created symbol item
+		counter_symbol->object.type = &type_int;
+		counter_symbol->object.u.number.flags = NUMBER_IS_DEFINED;
+		counter_symbol->object.u.number.addr_refs = 0;
+		counter_symbol->object.u.number.val.intval = 0;
+	} else if (counter_symbol->object.type != &type_int) {
+		// sanity check: it must be an int!
 		Bug_found("ForwardAnonCounterNotInt", 0);
+	}
 	// make sure it gets reset to zero in each new pass
 	if (counter_symbol->pass != pass.number) {
 		counter_symbol->pass = pass.number;

src/symbol.h

@@ -31,9 +31,11 @@ extern struct rwnode	*symbols_forest[];	// trees (because of 8-bit hash)
 
 // function acts upon the symbol's flag bits and produces an error if needed.
 extern void symbol_set_object(struct symbol *symbol, struct object *new_obj, boolean change_allowed);
-// search for symbol. create if nonexistant. if created, assign flags.
-// name must be held in GlobalDynaBuf.
-extern struct symbol *symbol_find(scope_t, int flags);
+// search for symbol. if it does not exist, create with NULL object (CAUTION!).
+// the symbol name must be held in GlobalDynaBuf.
+extern struct symbol *symbol_find(scope_t scope);
+// FIXME
+extern void symbol_forcebit(struct symbol *symbol, int force_bit);
 // set global symbol to value, no questions asked (for "-D" switch)
 // name must be held in GlobalDynaBuf.
 extern void symbol_define(intval_t value);

src/version.h

@@ -9,7 +9,7 @@
 
 #define RELEASE		"0.96.5"	// update before release	FIXME
 #define CODENAME	"Fenchurch"	// update before release
-#define CHANGE_DATE	"3 June"	// update before release	FIXME
+#define CHANGE_DATE	"5 June"	// update before release	FIXME
 #define CHANGE_YEAR	"2020"		// update before release
 //#define HOME_PAGE	"http://home.pages.de/~mac_bacon/smorbrod/acme/"
 #define HOME_PAGE	"http://sourceforge.net/p/acme-crossass/"	// FIXME