If an if or do statement always exits, following statements are dead.

pkg/analyzer/test/generated/non_hint_code_test.dart

Index: pkg/analyzer/test/generated/non_hint_code_test.dart
diff --git a/pkg/analyzer/test/generated/non_hint_code_test.dart b/pkg/analyzer/test/generated/non_hint_code_test.dart
index 9fc1dfb311802623f4f9e70422f44aa7148fb980..226f5e50b096b39280f2b9f6349dcbfcd5c96b22 100644
--- a/pkg/analyzer/test/generated/non_hint_code_test.dart
+++ b/pkg/analyzer/test/generated/non_hint_code_test.dart
@@ -158,6 +158,19 @@ f() {
     verify([source]);
   }
 
+  void test_deadCode_statementAfterIfWithoutElse() {
+    Source source = addSource(r'''
+f() {
+  if (1 < 0) {
+    return;
+  }
+  int a = 1;
+}''');
+    computeLibrarySourceErrors(source);
+    assertNoErrors(source);
+    verify([source]);
+  }
+
   void test_deprecatedMemberUse_inDeprecatedClass() {
     Source source = addSource(r'''
 @deprecated