harec

commit 6e99b03605977e9b357315de51894fb1d42a995c
parent 4ca07c38df734a99ea5162bafd04b871add59be2
Author: Eyal Sawady <ecs@d2evs.net>
Date:   Fri,  1 Jan 2021 13:46:06 -0500

Implement implicit dereferencing

Also update array tests

Diffstat:
M
src/check.c
 | 
6
++++++
M
src/gen.c
 | 
19
+++++++++++++++++++
M
tests/01-arrays.ha
 | 
8
++++++++

3 files changed, 33 insertions(+), 0 deletions(-)
diff --git a/src/check.c b/src/check.c
@@ -72,6 +72,12 @@ check_expr_access(struct context *ctx,
 		check_expression(ctx, aexpr->access.index, expr->access.index);
 		const struct type *atype = expr->access.array->result;
 		const struct type *itype = expr->access.index->result;
+		while (atype->storage == TYPE_STORAGE_POINTER) {
+			expect(&aexpr->access.array->loc,
+				!(atype->pointer.flags & PTR_NULLABLE),
+				"Cannot index nullable pointer");
+			atype = atype->pointer.referent;
+		}
 		expect(&aexpr->access.array->loc,
 			atype->storage == TYPE_STORAGE_ARRAY || atype->storage == TYPE_STORAGE_SLICE,
 			"Cannot index non-array, non-slice object");
diff --git a/src/gen.c b/src/gen.c
@@ -288,12 +288,31 @@ gen_expr_access_index(struct gen_context *ctx,
 	const struct qbe_value *out)
 {
 	const struct type *atype = expr->access.array->result;
+	while (atype->storage == TYPE_STORAGE_POINTER) {
+		atype = atype->pointer.referent;
+	}
 	assert(atype->storage == TYPE_STORAGE_ARRAY); // TODO: Slices
 
 	struct qbe_value obj = {0};
 	gen_temp(ctx, &obj, &qbe_long, "object.%d"); // XXX: ARCH
 	gen_expression(ctx, expr->access.array, &obj);
 
+	atype = expr->access.array->result;
+	if (atype->storage == TYPE_STORAGE_POINTER) {
+		// We get one dereference for free because the array is stored
+		// indirectly
+		atype = atype->pointer.referent;
+	}
+	while (atype->storage == TYPE_STORAGE_POINTER) {
+		qval_deref(&obj);
+		struct qbe_value deref;
+		gen_loadtemp(ctx, &deref, &obj,
+			qtype_for_type(ctx, atype->pointer.referent, false),
+			type_is_signed(atype->pointer.referent));
+		obj = deref;
+		atype = atype->pointer.referent;
+	}
+
 	struct qbe_value index = {0};
 	gen_temp(ctx, &index, &qbe_long, "index.%d");
 	gen_expression(ctx, expr->access.index, &index);
diff --git a/tests/01-arrays.ha b/tests/01-arrays.ha
@@ -1,8 +1,16 @@
 fn indexing() void = {
 	let x = [1, 2, 3];
+	let y = &x;
+	let z = &y;
 	assert(x[0] == 1);
 	assert(x[1] == 2);
 	assert(x[2] == 3);
+	assert(y[0] == 1);
+	assert(y[1] == 2);
+	assert(y[2] == 3);
+	assert(z[0] == 1);
+	assert(z[1] == 2);
+	assert(z[2] == 3);
 };
 
 fn measurements() void = {