[qfcc] Give select expressions their own type

While get_selector does the job of getting a selector from a selector
reference expression, I have long considered lumping various expression
types under ex_expr to be a mistake. Not only is this a step towards
sorting that out, it will make working on #24 easier.

tools/qfcc/include/expr.h

@@ -53,6 +53,7 @@ typedef enum {
 	ex_symbol,		///< non-temporary variable (::symbol_t)
 	ex_temp,		///< temporary variable (::ex_temp_t)
 	ex_vector,		///< "vector" expression (::ex_vector_t)
+	ex_selector,	///< selector expression (::ex_selector_t)
 
 	ex_nil,			///< umm, nil, null. nuff said (0 of any type)
 	ex_value,		///< constant value (::ex_value_t)
@@ -121,6 +122,11 @@ typedef struct {
 	struct expr_s *list;	///< Linked list of element expressions.
 } ex_vector_t;
 
+typedef struct {
+	struct expr_s *sel_ref;	///< Reference to selector in selector table
+	struct selector_s *sel;	///< selector
+} ex_selector_t;
+
 /**	Pointer constant expression.
 
 	Represent a pointer to an absolute address in data space.
@@ -237,6 +243,7 @@ typedef struct expr_s {
 		struct symbol_s *symbol;		///< symbol reference expression
 		ex_temp_t   temp;				///< temporary variable expression
 		ex_vector_t vector;				///< vector expression list
+		ex_selector_t selector;			///< selector ref and name
 		ex_value_t *value;				///< constant value
 		element_chain_t compound;		///< compound initializer
 		ex_memset_t memset;				///< memset expr params

tools/qfcc/source/dot_expr.c

@@ -47,6 +47,7 @@
 #include "qfalloca.h"
 
 #include "tools/qfcc/include/expr.h"
+#include "tools/qfcc/include/method.h"
 #include "tools/qfcc/include/symtab.h"
 #include "tools/qfcc/include/type.h"
 #include "tools/qfcc/include/strpool.h"
@@ -426,6 +427,15 @@ print_vector (dstring_t *dstr, expr_t *e, int level, int id, expr_t *next)
 			   e->line);
 }
 
+static void
+print_selector (dstring_t *dstr, expr_t *e, int level, int id, expr_t *next)
+{
+	int         indent = level * 2 + 2;
+
+	dasprintf (dstr, "%*se_%p [label=\"%s\"];\n", indent, "", e,
+			   e->e.selector.sel->name);
+}
+
 static void
 print_nil (dstring_t *dstr, expr_t *e, int level, int id, expr_t *next)
 {
@@ -564,6 +574,7 @@ _print_expr (dstring_t *dstr, expr_t *e, int level, int id, expr_t *next)
 		[ex_symbol] = print_symbol,
 		[ex_temp] = print_temp,
 		[ex_vector] = print_vector,
+		[ex_selector] = print_selector,
 		[ex_nil] = print_nil,
 		[ex_value] = print_value,
 		[ex_compound] = print_compound,

tools/qfcc/source/expr.c

@@ -256,6 +256,8 @@ get_type (expr_t *e)
 			break;
 		case ex_vector:
 			return e->e.vector.type;
+		case ex_selector:
+			return &type_SEL;
 		case ex_count:
 			internal_error (e, "invalid expression");
 	}
@@ -448,6 +450,11 @@ copy_expr (expr_t *e)
 				t = t->next;
 			}
 			return n;
+		case ex_selector:
+			n = new_expr ();
+			*n = *e;
+			n->e.selector.sel_ref = copy_expr (e->e.selector.sel_ref);
+			return n;
 		case ex_compound:
 			n = new_expr ();
 			*n = *e;
@@ -1641,6 +1648,7 @@ unary_expr (int op, expr_t *e)
 				case ex_state:
 				case ex_compound:
 				case ex_memset:
+				case ex_selector:
 					internal_error (e, 0);
 				case ex_uexpr:
 					if (e->e.expr.op == '-') {
@@ -1732,6 +1740,7 @@ unary_expr (int op, expr_t *e)
 				case ex_state:
 				case ex_compound:
 				case ex_memset:
+				case ex_selector:
 					internal_error (e, 0);
 				case ex_bool:
 					return new_bool_expr (e->e.bool.false_list,
@@ -1802,6 +1811,7 @@ unary_expr (int op, expr_t *e)
 				case ex_state:
 				case ex_compound:
 				case ex_memset:
+				case ex_selector:
 					internal_error (e, 0);
 				case ex_uexpr:
 					if (e->e.expr.op == '~')

tools/qfcc/source/expr_assign.c

@@ -135,6 +135,7 @@ is_lvalue (const expr_t *expr)
 		case ex_nil:
 		case ex_value:
 		case ex_error:
+		case ex_selector:
 			break;
 		case ex_count:
 			internal_error (expr, "invalid expression");

tools/qfcc/source/expr_obj.c

@@ -90,7 +90,7 @@ expr_t *
 selector_expr (keywordarg_t *selector)
 {
 	dstring_t  *sel_id = dstring_newstr ();
-	expr_t     *sel;
+	expr_t     *sel_ref;
 	symbol_t   *sel_sym;
 	symbol_t   *sel_table;
 	int         index;
@@ -111,10 +111,15 @@ selector_expr (keywordarg_t *selector)
 			symtab_addsymbol (pr.symtab, sel_table);
 		reloc_def_def (sel_table->s.def, sel_sym->s.def);
 	}
-	sel = new_symbol_expr (sel_sym);
+	sel_ref = new_symbol_expr (sel_sym);
+	sel_ref = new_binary_expr ('&', sel_ref, new_short_expr (index));
+	sel_ref->e.expr.type = &type_SEL;
+
+	expr_t     *sel = new_expr ();
+	sel->type = ex_selector;
+	sel->e.selector.sel_ref = sel_ref;
+	sel->e.selector.sel = get_selector (sel_ref);
 	dstring_delete (sel_id);
-	sel = new_binary_expr ('&', sel, new_short_expr (index));
-	sel->e.expr.type = &type_SEL;
 	return sel;
 }
 

tools/qfcc/source/method.c

@@ -483,6 +483,9 @@ get_selector (expr_t *sel)
 {
 	selector_t  _sel = {0, 0, 0};
 
+	if (sel->type == ex_selector) {
+		return sel->e.selector.sel;
+	}
 	if (sel->type != ex_expr && sel->e.expr.op != '&'
 		&& !is_SEL(sel->e.expr.type)) {
 		error (sel, "not a selector");

tools/qfcc/source/statements.c

@@ -50,6 +50,7 @@
 #include "tools/qfcc/include/dot.h"
 #include "tools/qfcc/include/expr.h"
 #include "tools/qfcc/include/function.h"
+#include "tools/qfcc/include/method.h"
 #include "tools/qfcc/include/options.h"
 #include "tools/qfcc/include/qfcc.h"
 #include "tools/qfcc/include/reloc.h"
@@ -1450,6 +1451,12 @@ expr_value (sblock_t *sblock, expr_t *e, operand_t **op)
 	return sblock;
 }
 
+static sblock_t *
+expr_selector (sblock_t *sblock, expr_t *e, operand_t **op)
+{
+	return statement_subexpr (sblock, e->e.selector.sel_ref, op);
+}
+
 static sblock_t *
 statement_subexpr (sblock_t *sblock, expr_t *e, operand_t **op)
 {
@@ -1463,6 +1470,7 @@ statement_subexpr (sblock_t *sblock, expr_t *e, operand_t **op)
 		[ex_vector] = expr_vector_e,
 		[ex_nil] = expr_nil,
 		[ex_value] = expr_value,
+		[ex_selector] = expr_selector,
 	};
 	if (!e) {
 		*op = 0;