harec

commit b7c6dd96f53181bfca00d127c148f859a6c169c9
parent c7f7d297f83c885d47d0e0cad1b4579b7933a732
Author: Drew DeVault <sir@cmpwn.com>
Date:   Mon, 21 Dec 2020 14:42:37 -0500

check: access expressions

Diffstat:
M
include/expr.h
 | 
6
++++++
M
include/identifier.h
 | 
6
++++--
M
src/check.c
 | 
21
+++++++++++++++++++++
M
src/identifier.c
 | 
14
++++++++++++++
M
src/scope.c
 | 
12
+++++++++++-

5 files changed, 56 insertions(+), 3 deletions(-)
diff --git a/include/expr.h b/include/expr.h
@@ -5,6 +5,7 @@
 #include "types.h"
 
 struct scope;
+struct scope_object;
 
 enum expr_type {
 	EXPR_ACCESS,
@@ -32,6 +33,10 @@ enum expr_type {
 	EXPR_WHILE,
 };
 
+struct expression_access {
+	const struct scope_object *object;
+};
+
 // TODO: Stretchy constants
 union expression_constant {
 	bool bval;
@@ -65,6 +70,7 @@ struct expression {
 	enum expr_type type;
 	bool terminates;
 	union {
+		struct expression_access access;
 		union expression_constant constant;
 		struct expression_list list;
 		struct expression_return _return;
diff --git a/include/identifier.h b/include/identifier.h
@@ -1,6 +1,7 @@
 #ifndef HARE_IDENTIFIER_H
 #define HARE_IDENTIFIER_H
 #include <stddef.h>
+#include <stdbool.h>
 
 struct identifier {
 	char *name;
@@ -8,8 +9,9 @@ struct identifier {
 };
 
 char *identifier_unparse(const struct identifier *ident);
-int identifier_unparse_static(const struct identifier *ident,
-		char *buf, size_t len);
+int identifier_unparse_static(
+	const struct identifier *ident, char *buf, size_t len);
 void identifier_dup(struct identifier *new, const struct identifier *ident);
+bool identifier_eq(const struct identifier *a, const struct identifier *b);
 
 #endif
diff --git a/src/check.c b/src/check.c
@@ -27,6 +27,7 @@ expect(bool constraint, char *fmt, ...)
 		fprintf(stderr, "Error: ");
 		vfprintf(stderr, fmt, ap);
 		fprintf(stderr, "\n");
+		abort();
 	}
 }
 
@@ -34,6 +35,24 @@ static void check_expression(struct context *ctx,
 	const struct ast_expression *aexpr, struct expression *expr);
 
 static void
+check_expr_access(struct context *ctx,
+	const struct ast_expression *aexpr,
+	struct expression *expr)
+{
+	trace(TR_CHECK, "access");
+	expr->type = EXPR_ACCESS;
+
+	const struct scope_object *obj = scope_lookup(
+		ctx->scope, &aexpr->access.ident);
+	char buf[1024];
+	identifier_unparse_static(&aexpr->access.ident, buf, sizeof(buf));
+	expect(obj, "Unknown object %s", buf);
+
+	expr->result = obj->type;
+	expr->access.object = obj;
+}
+
+static void
 check_expr_constant(struct context *ctx,
 	const struct ast_expression *aexpr,
 	struct expression *expr)
@@ -140,6 +159,8 @@ check_expression(struct context *ctx,
 
 	switch (aexpr->type) {
 	case EXPR_ACCESS:
+		check_expr_access(ctx, aexpr, expr);
+		break;
 	case EXPR_ASSERT:
 	case EXPR_ASSIGN:
 	case EXPR_BINARITHM:
diff --git a/src/identifier.c b/src/identifier.c
@@ -73,3 +73,17 @@ identifier_dup(struct identifier *new, const struct identifier *ident)
 		identifier_dup(new->ns, ident->ns);
 	}
 }
+
+bool
+identifier_eq(const struct identifier *a, const struct identifier *b)
+{
+	if (!a && !b) {
+		return true;
+	} else if ((!a && b) || (a && !b)) {
+		return false;
+	}
+	if (strcmp(a->name, b->name) != 0) {
+		return false;
+	}
+	return identifier_eq(a->ns, b->ns);
+}
diff --git a/src/scope.c b/src/scope.c
@@ -74,5 +74,15 @@ scope_insert(struct scope *scope,
 const struct scope_object *
 scope_lookup(struct scope *scope, const struct identifier *ident)
 {
-	assert(0); // TODO
+	struct scope_object *o = scope->objects;
+	while (o) {
+		if (identifier_eq(&o->ident, ident)) {
+			return o;
+		}
+		o = o->next;
+	}
+	if (scope->parent) {
+		return scope_lookup(scope->parent, ident);
+	}
+	return NULL;
 }