[qfcc] Build the Ruamoko function parameters

The parameter defs are allocated from the parameter space using a
minimum alignment of 4, and varargs functions get a va_list struct in
place of the ...

An "args" expression is unconditionally injected into the call arguments
list at the place where ... is in the list, with arguments passed
through ... coming after the ...

Arguments get through to functions now, but there's problems with taking
the address of local variables: currently done using constant pointer
defs, which can't work for the base register addressing used in Ruamoko
progs.

With the update to test-bi's printf (and a hack to qfcc for lea),
triangle.r actually works, printing the expected results (but -1 instead
of 1 for equality, though that too is actually expected). qfcc will take
a bit longer because it seems there are some design issues in address
expressions (ambiguity, and a few other things) that have pretty much
always been there.

libs/gamecode/pr_exec.c

@@ -495,7 +495,7 @@ PR_SetupParams (progs_t *pr, int num_params, int min_alignment)
 	}
 	*pr->globals.stack = stack;
 	pr->pr_params[0] = pr->pr_globals + stack;
-	num_params = min (num_params, PR_MAX_PARAMS);
+	num_params = max (num_params, PR_MAX_PARAMS);
 	for (int i = 1; i < num_params; i++) {
 		pr->pr_params[i] = pr->pr_params[0] + i * 4;
 	}

tools/qfcc/include/expr.h

@@ -488,6 +488,14 @@ expr_t *new_temp_def_expr (const struct type_s *type);
 */
 expr_t *new_nil_expr (void);
 
+/** Create a new args expression node
+
+	Marker between real parameters and those passed through ...
+
+	\return			The new args expression node.
+*/
+expr_t *new_args_expr (void);
+
 /** Create a new value expression node.
 
 	\param value	The value to put in the expression node.
@@ -725,6 +733,7 @@ void convert_name (expr_t *e);
 expr_t *convert_vector (expr_t *e);
 
 expr_t *append_expr (expr_t *block, expr_t *e);
+expr_t *prepend_expr (expr_t *block, expr_t *e);
 
 expr_t *reverse_expr_list (expr_t *e);
 void print_expr (expr_t *e);

tools/qfcc/include/expr_names.h

@@ -61,5 +61,6 @@ EX_EXPR(branch)		///< branch expression  (::ex_branch_t)
 EX_EXPR(return)		///< return expression  (::ex_return_t)
 EX_EXPR(adjstk)		///< stack adjust expression  (::ex_adjstk_t)
 EX_EXPR(with)		///< with expression  (::ex_with_t)
+EX_EXPR(args)		///< @args marker in parameter list. no data
 
 ///@}

tools/qfcc/source/dot_expr.c

@@ -654,6 +654,15 @@ print_with (dstring_t *dstr, expr_t *e, int level, int id, expr_t *next)
 			   e->e.with.mode, e->e.with.reg, e->line);
 }
 
+static void
+print_args (dstring_t *dstr, expr_t *e, int level, int id, expr_t *next)
+{
+	int         indent = level * 2 + 2;
+
+	dasprintf (dstr, "%*se_%p [label=\"...\\n%d\"];\n", indent, "", e,
+			   e->line);
+}
+
 static void
 _print_expr (dstring_t *dstr, expr_t *e, int level, int id, expr_t *next)
 {
@@ -682,6 +691,7 @@ _print_expr (dstring_t *dstr, expr_t *e, int level, int id, expr_t *next)
 		[ex_return] = print_return,
 		[ex_adjstk] = print_adjstk,
 		[ex_with] = print_with,
+		[ex_args] = print_args,
 	};
 	int         indent = level * 2 + 2;
 

tools/qfcc/source/expr.c

@@ -274,6 +274,8 @@ get_type (expr_t *e)
 			break;
 		case ex_assign:
 			return get_type (e->e.assign.dst);
+		case ex_args:
+			return &type_va_list;
 		case ex_count:
 			internal_error (e, "invalid expression");
 	}
@@ -525,6 +527,10 @@ copy_expr (expr_t *e)
 			*n = *e;
 			n->e.with.with = copy_expr (e->e.with.with);
 			return n;
+		case ex_args:
+			n = new_expr ();
+			*n = *e;
+			return n;
 		case ex_count:
 			break;
 	}
@@ -725,6 +731,14 @@ new_nil_expr (void)
 	return e;
 }
 
+expr_t *
+new_args_expr (void)
+{
+	expr_t     *e = new_expr ();
+	e->type = ex_args;
+	return e;
+}
+
 expr_t *
 new_value_expr (ex_value_t *value)
 {
@@ -1709,6 +1723,7 @@ has_function_call (expr_t *e)
 		case ex_memset:
 		case ex_adjstk:
 		case ex_with:
+		case ex_args:
 			return 0;
 		case ex_count:
 			break;
@@ -1803,6 +1818,7 @@ unary_expr (int op, expr_t *e)
 				case ex_return:
 				case ex_adjstk:
 				case ex_with:
+				case ex_args:
 					internal_error (e, "unexpected expression type");
 				case ex_uexpr:
 					if (e->e.expr.op == '-') {
@@ -1907,6 +1923,7 @@ unary_expr (int op, expr_t *e)
 				case ex_return:
 				case ex_adjstk:
 				case ex_with:
+				case ex_args:
 					internal_error (e, "unexpected expression type");
 				case ex_bool:
 					return new_bool_expr (e->e.bool.false_list,
@@ -1989,6 +2006,7 @@ unary_expr (int op, expr_t *e)
 				case ex_return:
 				case ex_adjstk:
 				case ex_with:
+				case ex_args:
 					internal_error (e, "unexpected expression type");
 				case ex_uexpr:
 					if (e->e.expr.op == '~')
@@ -2048,12 +2066,13 @@ build_function_call (expr_t *fexpr, const type_t *ftype, expr_t *params)
 {
 	expr_t     *e;
 	expr_t     *p;
-	int         arg_count = 0, parm_count = 0;
+	int         arg_count = 0, param_count = 0;
 	int         i;
 	expr_t     *args = 0, **a = &args;
 	type_t     *arg_types[PR_MAX_PARAMS];
 	expr_t     *arg_exprs[PR_MAX_PARAMS][2];
 	int         arg_expr_count = 0;
+	int         emit_args = 0;
 	expr_t     *assign;
 	expr_t     *call;
 	expr_t     *err = 0;
@@ -2074,7 +2093,8 @@ build_function_call (expr_t *fexpr, const type_t *ftype, expr_t *params)
 			if (options.warnings.traditional)
 				warning (fexpr, "too few arguments");
 		}
-		parm_count = -ftype->t.func.num_params - 1;
+		param_count = -ftype->t.func.num_params - 1;
+		emit_args = 1;
 	} else if (ftype->t.func.num_params >= 0) {
 		if (arg_count > ftype->t.func.num_params) {
 			return error (fexpr, "too many arguments");
@@ -2084,13 +2104,14 @@ build_function_call (expr_t *fexpr, const type_t *ftype, expr_t *params)
 			if (options.warnings.traditional)
 				warning (fexpr, "too few arguments");
 		}
-		parm_count = ftype->t.func.num_params;
+		param_count = ftype->t.func.num_params;
 	}
+	// params is reversed (a, b, c) -> c, b, a
 	for (i = arg_count - 1, e = params; i >= 0; i--, e = e->next) {
 		type_t     *t;
 
 		if (e->type == ex_compound) {
-			if (i < parm_count) {
+			if (i < param_count) {
 				t = ftype->t.func.param_types[i];
 			} else {
 				return error (e, "cannot pass compound initializer "
@@ -2109,7 +2130,7 @@ build_function_call (expr_t *fexpr, const type_t *ftype, expr_t *params)
 		if (type_size (t) > type_size (&type_param))
 			err = error (e, "formal parameter %d is too large to be passed by"
 						 " value", i + 1);
-		if (i < parm_count) {
+		if (i < param_count) {
 			if (e->type == ex_nil)
 				convert_nil (e, t = ftype->t.func.param_types[i]);
 			if (e->type == ex_bool)
@@ -2154,7 +2175,13 @@ build_function_call (expr_t *fexpr, const type_t *ftype, expr_t *params)
 
 	call = expr_file_line (new_block_expr (), fexpr);
 	call->e.block.is_call = 1;
+	// args is built in reverse order so it matches params
 	for (p = params, i = 0; p; p = p->next, i++) {
+		if (emit_args && arg_count - i == param_count) {
+			emit_args = 0;
+			*a = new_args_expr ();
+			a = &(*a)->next;
+		}
 		expr_t     *e = p;
 		if (e->type == ex_compound) {
 			e = expr_file_line (initialized_temp_expr (arg_types[i], e), e);
@@ -2175,6 +2202,11 @@ build_function_call (expr_t *fexpr, const type_t *ftype, expr_t *params)
 		}
 		a = &(*a)->next;
 	}
+	if (emit_args) {
+		emit_args = 0;
+		*a = new_args_expr ();
+		a = &(*a)->next;
+	}
 	for (i = 0; i < arg_expr_count - 1; i++) {
 		assign = assign_expr (arg_exprs[i][1], arg_exprs[i][0]);
 		append_expr (call, expr_file_line (assign, arg_exprs[i][0]));

tools/qfcc/source/expr_assign.c

@@ -140,6 +140,7 @@ is_lvalue (const expr_t *expr)
 		case ex_return:
 		case ex_adjstk:
 		case ex_with:
+		case ex_args:
 			break;
 		case ex_count:
 			internal_error (expr, "invalid expression");

tools/qfcc/source/function.c

@@ -486,33 +486,15 @@ check_function (symbol_t *fsym)
 }
 
 static void
-build_scope (symbol_t *fsym, symtab_t *parent)
+build_v6p_scope (symbol_t *fsym)
 {
 	int         i;
 	param_t    *p;
 	symbol_t   *args = 0;
 	symbol_t   *param;
-	symtab_t   *parameters;
+	symtab_t   *parameters = fsym->s.func->parameters;
-	symtab_t   *locals;
+	symtab_t   *locals = fsym->s.func->locals;
 
-	check_function (fsym);
-
-	fsym->s.func->label_scope = new_symtab (0, stab_local);
-
-	parameters = new_symtab (parent, stab_local);
-	parameters->space = defspace_new (ds_virtual);
-	fsym->s.func->parameters = parameters;
-
-	locals = new_symtab (parameters, stab_local);
-	locals->space = defspace_new (ds_virtual);
-	fsym->s.func->locals = locals;
-
-	if (!fsym->s.func) {
-		internal_error (0, "function %s not defined", fsym->name);
-	}
-	if (!is_func (fsym->s.func->type)) {
-		internal_error (0, "function type %s not a funciton", fsym->name);
-	}
 	if (fsym->s.func->type->t.func.num_params < 0) {
 		args = new_symbol_type (".args", &type_va_list);
 		initialize_def (args, 0, parameters->space, sc_param, locals);
@@ -541,6 +523,78 @@ build_scope (symbol_t *fsym, symtab_t *parent)
 	}
 }
 
+static void
+create_param (symtab_t *parameters, symbol_t *param)
+{
+	defspace_t *space = parameters->space;
+	def_t      *def = new_def (param->name, 0, space, sc_param);
+	int         size = type_size (param->type);
+	int         alignment = param->type->alignment;
+	if (alignment < 4) {
+		alignment = 4;
+	}
+	def->offset = defspace_alloc_aligned_highwater (space, size, alignment);
+	def->type = param->type;
+	param->s.def = def;
+	param->sy_type = sy_var;
+	symtab_addsymbol (parameters, param);
+}
+
+static void
+build_rua_scope (symbol_t *fsym)
+{
+	for (param_t *p = fsym->params; p; p = p->next) {
+		symbol_t   *param;
+		if (!p->selector && !p->type && !p->name) {
+			// ellipsis marker
+			param = new_symbol_type (".args", &type_va_list);
+		} else {
+			if (!p->type) {
+				continue;					// non-param selector
+			}
+			if (!p->name) {
+				error (0, "parameter name omitted");
+				p->name = save_string ("");
+			}
+			param = new_symbol_type (p->name, p->type);
+		}
+		create_param (fsym->s.func->parameters, param);
+		param->s.def->reg = fsym->s.func->temp_reg;;
+	}
+}
+
+static void
+build_scope (symbol_t *fsym, symtab_t *parent)
+{
+	symtab_t   *parameters;
+	symtab_t   *locals;
+
+	if (!fsym->s.func) {
+		internal_error (0, "function %s not defined", fsym->name);
+	}
+	if (!is_func (fsym->s.func->type)) {
+		internal_error (0, "function type %s not a funciton", fsym->name);
+	}
+
+	check_function (fsym);
+
+	fsym->s.func->label_scope = new_symtab (0, stab_local);
+
+	parameters = new_symtab (parent, stab_local);
+	parameters->space = defspace_new (ds_virtual);
+	fsym->s.func->parameters = parameters;
+
+	locals = new_symtab (parameters, stab_local);
+	locals->space = defspace_new (ds_virtual);
+	fsym->s.func->locals = locals;
+
+	if (options.code.progsversion == PROG_VERSION) {
+		build_rua_scope (fsym);
+	} else {
+		build_v6p_scope (fsym);
+	}
+}
+
 function_t *
 new_function (const char *name, const char *nice_name)
 {

tools/qfcc/source/statements.c

@@ -1026,10 +1026,19 @@ expr_call_v6p (sblock_t *sblock, expr_t *call, operand_t **op)
 	statement_t *s;
 
 	// function arguments are in reverse order
-	for (a = args; a; a = a->next)
+	for (a = args; a; a = a->next) {
+		if (a->type == ex_args) {
+			// v6p uses callN and pr_argc
+			continue;
+		}
 		count++;
+	}
 	ind = count;
 	for (a = args; a; a = a->next) {
+		if (a->type == ex_args) {
+			// v6p uses callN and pr_argc
+			continue;
+		}
 		ind--;
 		param = new_param_expr (get_type (a), ind);
 		if (count && options.code.progsversion != PROG_ID_VERSION && ind < 2) {
@@ -1091,8 +1100,11 @@ expr_call (sblock_t *sblock, expr_t *call, operand_t **op)
 	defspace_t *arg_space = current_func->arguments;
 	expr_t     *func = call->e.branch.target;
 	expr_t     *args = call->e.branch.args;
+	expr_t     *args_va_list = 0;	// .args (...) parameter
+	expr_t     *args_params = 0;	// first arg in ...
 	operand_t  *use = 0;
 	operand_t  *kill = 0;
+	int         num_params = 0;
 
 	defspace_reset (arg_space);
 
@@ -1111,9 +1123,21 @@ expr_call (sblock_t *sblock, expr_t *call, operand_t **op)
 		def->offset = defspace_alloc_aligned_highwater (arg_space, size,
 														alignment);
 		def->type = arg_type;
-		expr_t     *assign = assign_expr (new_def_expr (def), a);
+		def->reg = current_func->temp_reg;
+		expr_t     *def_expr = expr_file_line (new_def_expr (def), call);
+		if (a->type == ex_args) {
+			args_va_list = def_expr;
+		} else {
+			if (args_va_list && !args_params) {
+				args_params = def_expr;
+			}
+			if (args_va_list) {
+				num_params++;
+			}
+			expr_t     *assign = assign_expr (def_expr, a);
 			expr_file_line (assign, call);
 			sblock = statement_slist (sblock, assign);
+		}
 
 		// The call both uses and kills the arguments: use is obvious, but kill
 		// is because the callee has direct access to them and might modify
@@ -1126,6 +1150,31 @@ expr_call (sblock_t *sblock, expr_t *call, operand_t **op)
 		k->next = kill;
 		kill = k;
 	}
+	if (args_va_list) {
+		expr_t     *assign;
+		expr_t     *count;
+		expr_t     *list;
+		expr_t     *args_count = field_expr (args_va_list,
+											 new_name_expr ("count"));
+		expr_t     *args_list = field_expr (args_va_list,
+											new_name_expr ("list"));
+		expr_file_line (args_count, call);
+		expr_file_line (args_list, call);
+
+		count = new_short_expr (num_params);
+		assign = assign_expr (args_count, count);
+		expr_file_line (assign, call);
+		sblock = statement_slist (sblock, assign);
+
+		if (args_params) {
+			list = address_expr (args_params, 0, &type_param);
+		} else {
+			list = new_nil_expr ();
+		}
+		assign = assign_expr (args_list, list);
+		expr_file_line (assign, call);
+		sblock = statement_slist (sblock, assign);
+	}
 	statement_t *s = new_statement (st_func, "call", call);
 	sblock = statement_subexpr (sblock, func, &s->opa);
 	if (!op) {

tools/qfcc/test/test-bi.c

@@ -55,6 +55,19 @@ bi_printf (progs_t *pr)
 	else
 		dstring_clear (dstr);
 
+	if (pr->progs->version == PROG_VERSION) {
+		__auto_type va_list = &P_PACKED (pr, pr_va_list_t, 1);
+		count = va_list->count;
+		if (count) {
+			args = alloca (count * sizeof (pr_type_t *));
+			for (int i = 0; i < count; i++) {
+				args[i] = &pr->pr_globals[va_list->list + i * 4];
+			}
+		} else {
+			args = 0;
+		}
+	}
+
 	PR_Sprintf (pr, dstr, "bi_printf", fmt, count, args);
 	if (dstr->str)
 		fputs (dstr->str, stdout);