[turbofan] Introduces a step to verify the machine graph.

src/compiler/pipeline.cc

Index: src/compiler/pipeline.cc
diff --git a/src/compiler/pipeline.cc b/src/compiler/pipeline.cc
index 0041da25bf31e00b18b135849e1ddf97c1f2390d..cf64c0585ae2161fc02b0ef960ab8b9de018cae0 100644
--- a/src/compiler/pipeline.cc
+++ b/src/compiler/pipeline.cc
@@ -48,6 +48,7 @@
 #include "src/compiler/loop-analysis.h"
 #include "src/compiler/loop-peeling.h"
 #include "src/compiler/loop-variable-optimizer.h"
+#include "src/compiler/machine-graph-verifier.h"
 #include "src/compiler/machine-operator-reducer.h"
 #include "src/compiler/memory-optimizer.h"
 #include "src/compiler/move-optimizer.h"
@@ -1749,6 +1750,12 @@ bool PipelineImpl::ScheduleAndSelectInstructions(Linkage* linkage) {
         info(), data->graph(), data->schedule()));
   }
 
+  if (FLAG_turbo_verify_machine_graph) {
+    Zone temp_zone(data->isolate()->allocator());
+    MachineGraphVerifier::Run(data->graph(), data->schedule(), linkage,
+                              &temp_zone);
+  }
+
   data->InitializeInstructionSequence(call_descriptor);
 
   data->InitializeFrameData(call_descriptor);