[turbofan] Build s/NULL/nullptr/g and CHECK(x != nullptr) to CHECK_NOT_NULL(x).

src/compiler/coalesced-live-ranges.h

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COALESCED_LIVE_RANGES_H_
 #define V8_COALESCED_LIVE_RANGES_H_
 
 #include "src/compiler/register-allocator.h"
 #include "src/zone-containers.h"
 
@@ skipping 71 matching lines @@
     return AllocatedInterval(pos, LifetimePosition::Invalid(), nullptr);
   }
 
   // Intersection utilities.
   static bool Intersects(LifetimePosition a_start, LifetimePosition a_end,
                          LifetimePosition b_start, LifetimePosition b_end) {
     return a_start < b_end && b_start < a_end;
   }
 
   bool QueryIntersectsAllocatedInterval() const {
-    DCHECK(query_ != nullptr);
+    DCHECK_NOT_NULL(query_);
     return pos_ != intervals_->end() &&
            Intersects(query_->start(), query_->end(), pos_->start_, pos_->end_);
   }
 
   void Invalidate() {
     query_ = nullptr;
     pos_ = intervals_->end();
   }
 
   const UseInterval* query_;
@@ skipping 46 matching lines @@
 
   IntervalStore intervals_;
   DISALLOW_COPY_AND_ASSIGN(CoalescedLiveRanges);
 };
 
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 #endif  // V8_COALESCED_LIVE_RANGES_H_