harec

commit 416e6b362d6d0c747fada4713159c0c6a0c8cf89
parent a225cfca23cd9ae3c7a6f17c22d69622ee1d490e
Author: Drew DeVault <sir@cmpwn.com>
Date:   Fri, 19 Feb 2021 13:59:08 -0500

Implement variable shadowing

Diffstat:
M
include/scope.h
 | 
4
++--
M
src/scope.c
 | 
6
++++--

2 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/include/scope.h b/include/scope.h
@@ -20,13 +20,13 @@ struct scope_object {
 	struct identifier name, ident;
 	const struct type *type;
 	struct expression *value; // For O_CONST
-	struct scope_object *next;
+	struct scope_object *next, *prev;
 };
 
 struct scope {
 	enum expr_type type;
 	const char *label;
-	struct scope_object *objects;
+	struct scope_object *objects, *last;
 	struct scope_object **next; // List order matters for functions
 	struct scope *parent;
 };
diff --git a/src/scope.c b/src/scope.c
@@ -78,19 +78,21 @@ scope_insert(struct scope *scope, enum object_type otype,
 	}
 	*scope->next = o;
 	scope->next = &o->next;
+	o->prev = scope->last;
+	scope->last = o;
 	return o;
 }
 
 const struct scope_object *
 scope_lookup(struct scope *scope, const struct identifier *ident)
 {
-	struct scope_object *o = scope->objects;
+	struct scope_object *o = scope->last;
 	while (o) {
 		if (identifier_eq(&o->ident, ident)
 				|| identifier_eq(&o->name, ident)) {
 			return o;
 		}
-		o = o->next;
+		o = o->prev;
 	}
 	if (scope->parent) {
 		return scope_lookup(scope->parent, ident);