Make binary_expr fold constants

This is where constant folding should have happened all along. While
unary_expr should fold constants too, it seems to already try to do so
and it's a bit much of a mess to clean up right now.

tools/qfcc/source/expr.c

@@ -1280,7 +1280,7 @@ test_expr (expr_t *e)
 	new = binary_expr (NE, e, new);
 	new->line = e->line;
 	new->file = e->file;
-	return fold_constants (new);
+	return new;
 }
 
 void
@@ -2130,10 +2130,10 @@ array_expr (expr_t *array, expr_t *index)
 			|| ind - array_type->t.array.base >= array_type->t.array.size))
 			return error (index, "array index out of bounds");
 	scale = new_integer_expr (type_size (array_type->t.array.type));
-	index = fold_constants (binary_expr ('*', index, scale));
+	index = binary_expr ('*', index, scale);
 	base = new_integer_expr (array_type->t.array.base);
-	offset = fold_constants (binary_expr ('*', base, scale));
+	offset = binary_expr ('*', base, scale);
-	index = fold_constants (binary_expr ('-', index, offset));
+	index = binary_expr ('-', index, offset);
 	if (is_short_val (index))
 		ind = expr_short (index);
 	if (is_integer_val (index))

tools/qfcc/source/expr_binary.c

@@ -42,8 +42,11 @@ typedef struct {
 	type_t     *type;
 	type_t     *a_cast;
 	type_t     *b_cast;
+	expr_t     *(*process)(int op, expr_t *e1, expr_t *e2);
 } expr_type_t;
 
+static expr_t *pointer_arithmetic (int op, expr_t *e1, expr_t *e2);
+
 static expr_type_t string_string[] = {
 	{'+',	&type_string},
 	{EQ,	&type_integer},
@@ -157,8 +160,8 @@ static expr_type_t pointer_pointer[] = {
 };
 
 static expr_type_t pointer_integer[] = {
-	{'+',	&type_pointer},
+	{'+',	0, 0, 0, pointer_arithmetic},
-	{'-',	&type_pointer},
+	{'-',	0, 0, 0, pointer_arithmetic},
 	{0, 0}
 };
 #define pointer_uinteger pointer_integer
@@ -218,7 +221,7 @@ static expr_type_t integer_vector[] = {
 };
 
 static expr_type_t integer_pointer[] = {
-	{'+',	&type_pointer},
+	{'+',	&type_pointer, 0, &type_integer},
 	{0, 0}
 };
 
@@ -579,6 +582,25 @@ static expr_type_t **binary_expr_types[] = {
 	short_x,
 };
 
+static expr_t *
+pointer_arithmetic (int op, expr_t *e1, expr_t *e2)
+{
+	expr_t     *e;
+	type_t     *ptype = get_type (e1);
+
+	if (!is_pointer (ptype)) {
+		ptype = get_type (e2);
+	}
+	if (!is_pointer (ptype)) {
+		internal_error (e1, "pointer arithmetic on non-pointers");
+	}
+
+	e1 = cast_expr (&type_integer, e1);
+	e2 = cast_expr (&type_integer, e2);
+	e = binary_expr (op, e1, e2);
+	return cast_expr (ptype, e);
+}
+
 static expr_t *
 invalid_binary_expr (int op, expr_t *e1, expr_t *e2)
 {
@@ -780,9 +802,12 @@ binary_expr (int op, expr_t *e1, expr_t *e2)
 		e1 = cast_expr (expr_type->a_cast, e1);
 	if (expr_type->b_cast)
 		e2 = cast_expr (expr_type->b_cast, e2);
+	if (expr_type->process) {
+		return fold_constants (expr_type->process (op, e1, e2));
+	}
 
 	if ((e = reimplement_binary_expr (op, e1, e2)))
-		return e;
+		return fold_constants (e);
 
 	e = new_binary_expr (op, e1, e2);
 	e->e.expr.type = expr_type->type;
@@ -790,5 +815,5 @@ binary_expr (int op, expr_t *e1, expr_t *e2)
 		if (options.code.progsversion == PROG_ID_VERSION)
 			e->e.expr.type = &type_float;
 	}
-	return e;
+	return fold_constants (e);
 }

tools/qfcc/source/qc-parse.y

@@ -180,7 +180,7 @@ int yylex (void);
 %type	<symbol>	methoddef
 %type	<expr>		opt_initializer var_initializer local_def
 
-%type	<expr>		opt_init opt_expr cexpr fexpr expr element_list element
+%type	<expr>		opt_init opt_expr cexpr expr element_list element
 %type	<expr>		optional_state_expr texpr vector_expr
 %type	<expr>		statement statements compound_statement
 %type	<expr>		else label break_label continue_label
@@ -577,7 +577,7 @@ enumerator_list
 
 enumerator
 	: identifier				{ add_enum ($<symbol>0, $1, 0); }
-	| identifier '=' fexpr		{ add_enum ($<symbol>0, $1, $3); }
+	| identifier '=' expr		{ add_enum ($<symbol>0, $1, $3); }
 	;
 
 struct_specifier
@@ -846,9 +846,8 @@ abs_decl
 	;
 
 array_decl
-	: '[' fexpr ']'
+	: '[' expr ']'
 		{
-			$2 = fold_constants ($2);
 			if (!is_integer_val ($2) || expr_integer ($2) < 1) {
 				error (0, "invalid array size");
 				$$ = 0;
@@ -971,11 +970,11 @@ overloaded_identifier
 	;
 
 non_code_func
-	: '=' '#' fexpr
+	: '=' '#' expr
 		{
 			build_builtin_function ($<symbol>0, $3, 0);
 		}
-	| '=' fexpr
+	| '=' expr
 		{
 			symbol_t   *sym = $<symbol>0;
 			specifier_t spec = $<spec>-1;
@@ -1023,7 +1022,7 @@ opt_initializer
 	;
 
 var_initializer
-	: '=' fexpr									{ $$ = $2; }
+	: '=' expr									{ $$ = $2; }
 	| '=' '{' element_list optional_comma '}'	{ $$ = $3; }
 	;
 
@@ -1046,7 +1045,7 @@ element_list
 
 element
 	: '{' element_list optional_comma '}'		{ $$ = $2; }
-	| fexpr									{ $$ = $1; }
+	| expr										{ $$ = $1; }
 	;
 
 optional_comma
@@ -1128,7 +1127,7 @@ statement
 			else
 				error (0, "continue outside of loop");
 		}
-	| CASE fexpr ':'
+	| CASE expr ':'
 		{
 			$$ = case_label_expr (switch_block, $2);
 		}
@@ -1136,7 +1135,7 @@ statement
 		{
 			$$ = case_label_expr (switch_block, 0);
 		}
-	| SWITCH break_label '(' fexpr switch_block ')' compound_statement
+	| SWITCH break_label '(' expr switch_block ')' compound_statement
 		{
 			$$ = switch_expr (switch_block, break_label, $7);
 			switch_block = $5;
@@ -1295,7 +1294,7 @@ unary_expr
 	;
 
 vector_expr
-	: '[' fexpr ',' arg_list ']'
+	: '[' expr ',' arg_list ']'
 		{
 			expr_t     *t = $4;
 			while (t->next)
@@ -1338,12 +1337,8 @@ expr
 	| expr '%' expr				{ $$ = binary_expr ('%', $1, $3); }
 	;
 
-fexpr
-	: expr						{ $$ = fold_constants ($1); }
-	;
-
 texpr
-	: fexpr						{ $$ = convert_bool ($1, 1); }
+	: expr						{ $$ = convert_bool ($1, 1); }
 	;
 
 cexpr
@@ -1364,8 +1359,8 @@ opt_arg_list
 	;
 
 arg_list
-	: fexpr
+	: expr
-	| arg_list ',' fexpr
+	| arg_list ',' expr
 		{
 			$3->next = $1;
 			$$ = $3;
@@ -1874,7 +1869,7 @@ obj_messageexpr
 	;
 
 receiver
-	: fexpr
+	: expr
 	| CLASS_NAME
 		{
 			$$ = new_symbol_expr ($1);

tools/qfcc/source/switch.c

@@ -338,8 +338,6 @@ build_switch (expr_t *sw, case_node_t *tree, int op, expr_t *sw_val,
 		int         i;
 		expr_t     *range = binary_expr ('-', tree->high, tree->low);
 
-		range = fold_constants (range);
-
 		table_init = new_block_expr ();
 		for (i = 0; i <= high - low; i++) {
 			tree->labels[i]->e.label.used++;