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

BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/android/config.gni")
 import("//build/config/arm.gni")
 import("//build/config/dcheck_always_on.gni")
 import("//build/config/mips.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 
@@ skipping 1076 matching lines @@
     "src/compiler/liveness-analyzer.cc",
     "src/compiler/liveness-analyzer.h",
     "src/compiler/load-elimination.cc",
     "src/compiler/load-elimination.h",
     "src/compiler/loop-analysis.cc",
     "src/compiler/loop-analysis.h",
     "src/compiler/loop-peeling.cc",
     "src/compiler/loop-peeling.h",
     "src/compiler/loop-variable-optimizer.cc",
     "src/compiler/loop-variable-optimizer.h",
+    "src/compiler/machine-graph-verifier.cc",
+    "src/compiler/machine-graph-verifier.h",
     "src/compiler/machine-operator-reducer.cc",
     "src/compiler/machine-operator-reducer.h",
     "src/compiler/machine-operator.cc",
     "src/compiler/machine-operator.h",
     "src/compiler/memory-optimizer.cc",
     "src/compiler/memory-optimizer.h",
     "src/compiler/move-optimizer.cc",
     "src/compiler/move-optimizer.h",
     "src/compiler/node-aux-data.h",
     "src/compiler/node-cache.cc",
@@ skipping 1827 matching lines @@
   ]
 
   configs = [
     ":external_config",
     ":internal_config_base",
   ]
 }
 
 v8_fuzzer("wasm_data_section_fuzzer") {
 }