Allow bound check elimination to eliminate checks when both array length and index boundaries are e…

runtime/vm/flow_graph_builder.cc

Index: runtime/vm/flow_graph_builder.cc
diff --git a/runtime/vm/flow_graph_builder.cc b/runtime/vm/flow_graph_builder.cc
index 734cd4c574d5e40968ec2b7ffcee8a53802683ff..3246f49da5568b716e96757761c80e0c0a831bc9 100644
--- a/runtime/vm/flow_graph_builder.cc
+++ b/runtime/vm/flow_graph_builder.cc
@@ -1737,7 +1737,9 @@ void EffectGraphVisitor::VisitConstructorCallNode(ConstructorCallNode* node) {
                             node->arguments()->names(),
                             arguments);
     // List factories return kArrayCid or kGrowableObjectArrayCid.
-    call->set_result_cid(GetResultCidOfConstructor(node));
+    const intptr_t result_cid = GetResultCidOfConstructor(node);
+    call->set_result_cid(result_cid);
+    call->set_is_known_constructor(result_cid != kDynamicCid);
     ReturnDefinition(call);
     return;
   }