harec

commit ec59e8c5881a3b4c68e9c7d023f11f18c40d83cc
parent d1e5d917b8d94fc0c8efe3eaffb28dd7fab38553
Author: Drew DeVault <sir@cmpwn.com>
Date:   Sun, 24 Jan 2021 10:15:57 -0500

Fix several issues with aliases and match

Diffstat:
M
include/type_store.h
 | 
3
+++
M
src/check.c
 | 
14
+++++++++++---
M
src/gen.c
 | 
5
+++--
M
src/type_store.c
 | 
18
+++++++++++++++++-
M
src/types.c
 | 
1
-
M
tests/18-match.ha
 | 
17
+++++++++++++++++

6 files changed, 51 insertions(+), 7 deletions(-)
diff --git a/include/type_store.h b/include/type_store.h
@@ -41,4 +41,7 @@ const struct type *type_store_lookup_array(struct type_store *store,
 const struct type *type_store_lookup_slice(struct type_store *store,
 	const struct type *members);
 
+const struct type *type_store_lookup_alias(struct type_store *store,
+	const struct identifier *ident, const struct type *secondary);
+
 #endif
diff --git a/src/check.c b/src/check.c
@@ -87,7 +87,12 @@ check_expr_access(struct context *ctx,
 			expr->access.object = obj;
 			break;
 		case O_TYPE:
-			expect(&aexpr->loc, false, "Expected identifier, got type");
+			expect(&aexpr->loc,
+				type_dealias(obj->type)->storage == TYPE_STORAGE_VOID,
+				"Cannot use non-void type alias as constant");
+			expr->type = EXPR_CONSTANT;
+			expr->result = obj->type;
+			break;
 		}
 		break;
 	case ACCESS_INDEX:
@@ -874,7 +879,7 @@ check_expr_match(struct context *ctx,
 	check_expression(ctx, aexpr->match.value, value, NULL);
 	expr->match.value = value;
 
-	const struct type *type = value->result;
+	const struct type *type = type_dealias(value->result);
 	bool is_ptr = type->storage == TYPE_STORAGE_POINTER
 		&& type->pointer.flags & PTR_NULLABLE;
 	expect(&aexpr->match.value->loc,
@@ -1632,7 +1637,10 @@ scan_type(struct context *ctx, const struct ast_type_decl *decl)
 
 	struct identifier ident = {0};
 	mkident(ctx, &ident, &decl->ident);
-	scope_insert(ctx->unit, O_TYPE, &ident, &decl->ident, type, NULL);
+
+	const struct type *alias =
+		type_store_lookup_alias(ctx->store, &ident, type);
+	scope_insert(ctx->unit, O_TYPE, &ident, &decl->ident, alias, NULL);
 
 	if (type->storage == TYPE_STORAGE_ENUM) {
 		for (struct type_enum_value *value = type->_enum.values; value;
diff --git a/src/gen.c b/src/gen.c
@@ -1230,8 +1230,9 @@ gen_expr_constant(struct gen_context *ctx,
 	case Q_DOUBLE:
 		constd(&val, expr->constant.fval);
 		break;
-	case Q__AGGREGATE:
 	case Q__VOID:
+		return; // no-op
+	case Q__AGGREGATE:
 		assert(0); // Invariant
 	}
 
@@ -1549,7 +1550,7 @@ gen_expr_match(struct gen_context *ctx,
 	const struct expression *expr,
 	const struct qbe_value *out)
 {
-	const struct type *mtype = expr->match.value->result;
+	const struct type *mtype = type_dealias(expr->match.value->result);
 	switch (mtype->storage) {
 	case TYPE_STORAGE_TAGGED_UNION:
 		gen_match_tagged(ctx, expr, out);
diff --git a/src/type_store.c b/src/type_store.c
@@ -611,7 +611,7 @@ type_init_from_atype(struct type_store *store,
 	case TYPE_STORAGE_ALIAS:
 		obj = scope_lookup(store->check_context->scope, &atype->alias);
 		if (atype->unwrap) {
-			*type = *obj->type;
+			*type = *type_dealias(obj->type);
 			break;
 		}
 		assert(obj && obj->otype == O_TYPE); // TODO: Bubble this up
@@ -821,3 +821,19 @@ type_store_lookup_slice(struct type_store *store, const struct type *members)
 	};
 	return type_store_lookup_type(store, &slice);
 }
+
+const struct type *
+type_store_lookup_alias(struct type_store *store,
+	const struct identifier *ident, const struct type *secondary)
+{
+	struct type alias = {
+		.storage = TYPE_STORAGE_ALIAS,
+		.alias = {
+			.ident = *ident,
+			.type = secondary,
+		},
+		.size = secondary->size,
+		.align = secondary->align,
+	};
+	return type_store_lookup_type(store, &alias);
+}
diff --git a/src/types.c b/src/types.c
@@ -281,7 +281,6 @@ type_hash(const struct type *type)
 			hash = fnv1a_s(hash, ident->name);
 			hash = fnv1a(hash, 0);
 		}
-		hash = fnv1a_u32(hash, type_hash(type->alias.type));
 		break;
 	case TYPE_STORAGE_ARRAY:
 		hash = fnv1a_u32(hash, type_hash(type->array.members));
diff --git a/tests/18-match.ha b/tests/18-match.ha
@@ -47,9 +47,26 @@ fn pointer() void = {
 	assert(z == 1337);
 };
 
+type foo = void;
+type bar = void;
+type foobar = (foo | bar);
+
+fn alias() void = {
+	let cases: []foobar = [foo, bar];
+	let expected = [42, 24];
+	for (let i = 0z; i < len(cases); i += 1z) {
+		let y: int = match (cases[i]) {
+			foo => 42,
+			bar => 24,
+		};
+		assert(y == expected[i]);
+	};
+};
+
 export fn main() void = {
 	tagged();
 	termination();
 	default();
 	pointer();
+	alias();
 };