Make procedure parameters just named values rather than copied variables

5 files changed, 28 insertions, 40 deletions

diff --git a/src/check_expr.cpp b/src/check_expr.cpp
index 4c2133f4c..6845c167d 100644
--- a/src/check_expr.cpp
+++ b/src/check_expr.cpp
@@ -1533,8 +1533,14 @@ void check_unary_expr(CheckerContext *c, Operand *o, Token op, Ast *node) {
 			if (ast_node_expect(node, Ast_UnaryExpr)) {
 				ast_node(ue, UnaryExpr, node);
 				gbString str = expr_to_string(ue->expr);
-				error(op, "Cannot take the pointer address of '%s'", str);
-				gb_string_free(str);
+				defer (gb_string_free(str));
+
+				Entity *e = entity_of_ident(o->expr);
+				if (e != nullptr && (e->flags & EntityFlag_Param) != 0) {
+					error(op, "Cannot take the pointer address of '%s' which is a procedure parameter", str);
+				} else {
+					error(op, "Cannot take the pointer address of '%s'", str);
+				}
 			}
 			o->mode = Addressing_Invalid;
 			return;
@@ -5909,17 +5915,6 @@ void check_expr_with_type_hint(CheckerContext *c, Operand *o, Ast *e, Type *t) {
 	}
 }
 
-void check_set_mode_with_indirection(Operand *o, bool indirection) {
-	if (o->mode != Addressing_Immutable) {
-		if (indirection) {
-			o->mode = Addressing_Variable;
-		} else if (o->mode != Addressing_Variable &&
-		           o->mode != Addressing_Constant) {
-			o->mode = Addressing_Value;
-		}
-	}
-}
-
 bool check_set_index_data(Operand *o, Type *t, bool indirection, i64 *max_count) {
 	switch (t->kind) {
 	case Type_Basic:
@@ -5927,7 +5922,9 @@ bool check_set_index_data(Operand *o, Type *t, bool indirection, i64 *max_count)
 			if (o->mode == Addressing_Constant) {
 				*max_count = o->value.value_string.len;
 			}
-			check_set_mode_with_indirection(o, indirection);
+			if (o->mode != Addressing_Immutable && o->mode != Addressing_Constant) {
+				o->mode = Addressing_Variable;
+			}
 			o->type = t_u8;
 			return true;
 		}
@@ -5935,20 +5932,29 @@ bool check_set_index_data(Operand *o, Type *t, bool indirection, i64 *max_count)
 
 	case Type_Array:
 		*max_count = t->Array.count;
-		check_set_mode_with_indirection(o, indirection);
+		if (o->mode != Addressing_Immutable) {
+			if (indirection) {
+				o->mode = Addressing_Variable;
+			} else if (o->mode != Addressing_Variable &&
+			           o->mode != Addressing_Constant) {
+				o->mode = Addressing_Value;
+			}
+		}
 		o->type = t->Array.elem;
 		return true;
 
 	case Type_Slice:
 		o->type = t->Slice.elem;
-		if (o->mode != Addressing_Immutable) {
+		if (o->mode != Addressing_Immutable && o->mode != Addressing_Constant) {
 			o->mode = Addressing_Variable;
 		}
 		return true;
 
 	case Type_DynamicArray:
 		o->type = t->DynamicArray.elem;
-		check_set_mode_with_indirection(o, indirection);
+		if (o->mode != Addressing_Immutable && o->mode != Addressing_Constant) {
+			o->mode = Addressing_Variable;
+		}
 		return true;
 	}
 
diff --git a/src/check_stmt.cpp b/src/check_stmt.cpp
index 24f540930..e2090688f 100644
--- a/src/check_stmt.cpp
+++ b/src/check_stmt.cpp
@@ -303,9 +303,13 @@ Type *check_assignment_variable(CheckerContext *ctx, Operand *lhs, Operand *rhs)
 			}
 		}
 
+		Entity *e = entity_of_ident(lhs->expr);
+
 		gbString str = expr_to_string(lhs->expr);
 		if (lhs->mode == Addressing_Immutable) {
 			error(lhs->expr, "Cannot assign to an immutable: '%s'", str);
+		} else if (e != nullptr && e->flags & EntityFlag_Param) {
+			error(lhs->expr, "Cannot assign to '%s' which is a procedure parameter", str);
 		} else {
 			error(lhs->expr, "Cannot assign to '%s'", str);
 		}
diff --git a/src/check_type.cpp b/src/check_type.cpp
index df3c554dd..f4e5b49d0 100644
--- a/src/check_type.cpp
+++ b/src/check_type.cpp
@@ -1519,18 +1519,6 @@ Type *check_get_params(CheckerContext *ctx, Scope *scope, Ast *_params, bool *is
 			}
 		}
 
-		if (p->flags&FieldFlag_in) {
-			if (is_type_param) {
-				error(param, "'in' cannot be applied to a type parameter");
-				p->flags &= ~FieldFlag_in;
-			} else if (is_variadic) {
-				error(param, "'in' cannot be applied to a variadic parameter");
-				p->flags &= ~FieldFlag_in;
-			}
-		}
-
-		bool is_in = (p->flags&FieldFlag_in) != 0;
-
 		for_array(j, p->names) {
 			Ast *name = p->names[j];
 
@@ -1670,7 +1658,7 @@ Type *check_get_params(CheckerContext *ctx, Scope *scope, Ast *_params, bool *is
 
 					param = alloc_entity_const_param(scope, name->Ident.token, type, poly_const, is_type_polymorphic(type));
 				} else {
-					param = alloc_entity_param(scope, name->Ident.token, type, is_using, is_in);
+					param = alloc_entity_param(scope, name->Ident.token, type, is_using, true);
 					param->Variable.param_value = param_value;
 				}
 			}
diff --git a/src/parser.cpp b/src/parser.cpp
index d2e64f23c..a377b773c 100644
--- a/src/parser.cpp
+++ b/src/parser.cpp
@@ -2854,7 +2854,6 @@ enum FieldPrefixKind {
 	FieldPrefix_no_alias,
 	FieldPrefix_c_var_arg,
 	FieldPrefix_auto_cast,
-	FieldPrefix_in,
 };
 
 FieldPrefixKind is_token_field_prefix(AstFile *f) {
@@ -2865,9 +2864,6 @@ FieldPrefixKind is_token_field_prefix(AstFile *f) {
 	case Token_using:
 		return FieldPrefix_using;
 
-	case Token_in:
-		return FieldPrefix_in;
-
 	case Token_auto_cast:
 		return FieldPrefix_auto_cast;
 
@@ -2892,7 +2888,6 @@ u32 parse_field_prefixes(AstFile *f) {
 	i32 using_count     = 0;
 	i32 no_alias_count  = 0;
 	i32 c_vararg_count  = 0;
-	i32 in_count        = 0;
 	i32 auto_cast_count = 0;
 
 	for (;;) {
@@ -2910,14 +2905,12 @@ u32 parse_field_prefixes(AstFile *f) {
 		case FieldPrefix_using:     using_count     += 1; advance_token(f); break;
 		case FieldPrefix_no_alias:  no_alias_count  += 1; advance_token(f); break;
 		case FieldPrefix_c_var_arg: c_vararg_count  += 1; advance_token(f); break;
-		case FieldPrefix_in:        in_count        += 1; advance_token(f); break;
 		case FieldPrefix_auto_cast: auto_cast_count += 1; advance_token(f); break;
 		}
 	}
 	if (using_count     > 1) syntax_error(f->curr_token, "Multiple 'using' in this field list");
 	if (no_alias_count  > 1) syntax_error(f->curr_token, "Multiple '#no_alias' in this field list");
 	if (c_vararg_count  > 1) syntax_error(f->curr_token, "Multiple '#c_vararg' in this field list");
-	if (in_count        > 1) syntax_error(f->curr_token, "Multiple 'in' in this field list");
 	if (auto_cast_count > 1) syntax_error(f->curr_token, "Multiple 'auto_cast' in this field list");
 
 
@@ -2925,7 +2918,6 @@ u32 parse_field_prefixes(AstFile *f) {
 	if (using_count     > 0) field_flags |= FieldFlag_using;
 	if (no_alias_count  > 0) field_flags |= FieldFlag_no_alias;
 	if (c_vararg_count  > 0) field_flags |= FieldFlag_c_vararg;
-	if (in_count        > 0) field_flags |= FieldFlag_in;
 	if (auto_cast_count > 0) field_flags |= FieldFlag_auto_cast;
 	return field_flags;
 }
diff --git a/src/parser.hpp b/src/parser.hpp
index a6c9d190b..9f4f68a7b 100644
--- a/src/parser.hpp
+++ b/src/parser.hpp
@@ -186,8 +186,6 @@ enum FieldFlag {
 	FieldFlag_c_vararg  = 1<<3,
 	FieldFlag_auto_cast = 1<<4,
 
-	FieldFlag_in        = 1<<5,
-
 
 	FieldFlag_Results   = 1<<16,