Reference parameter doesn't work with vector subscript #1250.

releasenotes.md

@@ -51,6 +51,7 @@
 - Stdlib nolibc code bugs fixed.
 - Regression: duplicate symbols with static variable declared in macro #1248.
 - Unsplat with named parameters was accidentally disallowed.
+- Reference parameter doesn't work with vector subscript #1250.
 
 ### Stdlib changes
 - Added `remove_first_item` `remove_last_item` and `remove_item` as aliases for the `match` functions.

src/compiler/sema_expr.c

@@ -1537,14 +1537,20 @@ static bool sema_analyse_parameter(SemaContext *context, Expr *arg, Decl *param,
 	switch (kind)
 	{
 		case VARDECL_PARAM_REF:
+		{
 			// &foo
+			bool is_subscript = arg->expr_kind == EXPR_SUBSCRIPT;
+			if (is_subscript)
+			{
+				arg->expr_kind = EXPR_SUBSCRIPT_ADDR;
+			}
 			if (!sema_analyse_expr_lvalue(context, arg)) return false;
 			if (sema_arg_is_pass_through_ref(arg) && !sema_expr_check_assign(context, arg))
 			{
 				SEMA_NOTE(definition, "The definition is here.");
 				return false;
 			}
-			expr_insert_addr(arg);
+			if (!is_subscript) expr_insert_addr(arg);
 			*optional_ref |= IS_OPTIONAL(arg);
 			if (!sema_call_check_contract_param_match(context, param, arg))
 			{
@@ -1573,6 +1579,7 @@ static bool sema_analyse_parameter(SemaContext *context, Expr *arg, Decl *param,
 				}
 			}
 			break;
+		}
 		case VARDECL_PARAM:
 			// foo
 			if (!sema_analyse_expr_rhs(context, type, arg, true, no_match_ref)) return false;

test/test_suite/macros/ref_vector.c3t

@@ -0,0 +1,40 @@
+// #target: macos-x64
+module test;
+
+fn int main() {
+  int[<4>] vec;
+  @foo(vec[0]);
+  @foo(vec[2]);
+  assert(vec[0] == 1);
+  assert(vec[2] == 1);
+  return 1;
+}
+
+macro @foo(&ref) {
+  *ref += 1;
+}
+
+/* #expect: test.ll
+
+
+define i32 @main() #0 {
+entry:
+  %vec = alloca <4 x i32>, align 16
+  store <4 x i32> zeroinitializer, ptr %vec, align 16
+  %0 = load i32, ptr %vec, align 4
+  %add = add i32 %0, 1
+  store i32 %add, ptr %vec, align 4
+  %ptradd = getelementptr inbounds i8, ptr %vec, i64 8
+  %1 = load i32, ptr %ptradd, align 4
+  %add1 = add i32 %1, 1
+  store i32 %add1, ptr %ptradd, align 4
+  %2 = load <4 x i32>, ptr %vec, align 16
+  %3 = extractelement <4 x i32> %2, i64 0
+  %eq = icmp eq i32 %3, 1
+  call void @llvm.assume(i1 %eq)
+  %4 = load <4 x i32>, ptr %vec, align 16
+  %5 = extractelement <4 x i32> %4, i64 2
+  %eq2 = icmp eq i32 %5, 1
+  call void @llvm.assume(i1 %eq2)
+  ret i32 1
+}