[turbofan] Add --csa-verify flag that enables machine graph verification of code stubs.

src/compiler/pipeline.cc

Index: src/compiler/pipeline.cc
diff --git a/src/compiler/pipeline.cc b/src/compiler/pipeline.cc
index b7ce4c43538b9350d5adcf7a3d1b93890f57ba48..c5ddeca5e5764ef8827dd7991c14a5306cacfbf6 100644
--- a/src/compiler/pipeline.cc
+++ b/src/compiler/pipeline.cc
@@ -1762,10 +1762,15 @@ bool PipelineImpl::ScheduleAndSelectInstructions(Linkage* linkage,
         info(), data->graph(), data->schedule()));
   }
 
-  if (FLAG_turbo_verify_machine_graph != nullptr &&
-      (!strcmp(FLAG_turbo_verify_machine_graph, "*") ||
-       !strcmp(FLAG_turbo_verify_machine_graph,
-               data->info()->GetDebugName().get()))) {
+  // TODO(ishell): Always enable graph verification of stubs in debug mode
+  // once all the issues are fixed.
+  bool verify_stub_graph =
+      DEBUG_BOOL && FLAG_csa_verify && data->info()->IsStub();
+
+  if (verify_stub_graph || (FLAG_turbo_verify_machine_graph != nullptr &&
+                            (!strcmp(FLAG_turbo_verify_machine_graph, "*") ||
+                             !strcmp(FLAG_turbo_verify_machine_graph,
+                                     data->info()->GetDebugName().get())))) {
     Zone temp_zone(data->isolate()->allocator(), ZONE_NAME);
     MachineGraphVerifier::Run(data->graph(), data->schedule(), linkage,
                               &temp_zone);