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

src/compiler/machine-operator-reducer.cc

 // Copyright 2014 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.
 
 #include "src/compiler/machine-operator-reducer.h"
 
 #include "src/base/bits.h"
 #include "src/base/division-by-constant.h"
 #include "src/codegen.h"
 #include "src/compiler/diamond.h"
@@ skipping 926 matching lines @@
 Reduction MachineOperatorReducer::ReduceWord32Or(Node* node) {
   DCHECK_EQ(IrOpcode::kWord32Or, node->opcode());
   Int32BinopMatcher m(node);
   if (m.right().Is(0)) return Replace(m.left().node());    // x | 0  => x
   if (m.right().Is(-1)) return Replace(m.right().node());  // x | -1 => -1
   if (m.IsFoldable()) {                                    // K | K  => K
     return ReplaceInt32(m.left().Value() | m.right().Value());
   }
   if (m.LeftEqualsRight()) return Replace(m.left().node());  // x | x => x
 
-  Node* shl = NULL;
-  Node* shr = NULL;
+  Node* shl = nullptr;
+  Node* shr = nullptr;
   // Recognize rotation, we are matching either:
   //  * x << y | x >>> (32 - y) => x ror (32 - y), i.e  x rol y
   //  * x << (32 - y) | x >>> y => x ror y
   // as well as their commuted form.
   if (m.left().IsWord32Shl() && m.right().IsWord32Shr()) {
     shl = m.left().node();
     shr = m.right().node();
   } else if (m.left().IsWord32Shr() && m.right().IsWord32Shl()) {
     shl = m.right().node();
     shr = m.left().node();
   } else {
     return NoChange();
   }
 
   Int32BinopMatcher mshl(shl);
   Int32BinopMatcher mshr(shr);
   if (mshl.left().node() != mshr.left().node()) return NoChange();
 
   if (mshl.right().HasValue() && mshr.right().HasValue()) {
     // Case where y is a constant.
     if (mshl.right().Value() + mshr.right().Value() != 32) return NoChange();
   } else {
-    Node* sub = NULL;
-    Node* y = NULL;
+    Node* sub = nullptr;
+    Node* y = nullptr;
     if (mshl.right().IsInt32Sub()) {
       sub = mshl.right().node();
       y = mshr.right().node();
     } else if (mshr.right().IsInt32Sub()) {
       sub = mshr.right().node();
       y = mshl.right().node();
     } else {
       return NoChange();
     }
 
@@ skipping 99 matching lines @@
 MachineOperatorBuilder* MachineOperatorReducer::machine() const {
   return jsgraph()->machine();
 }
 
 
 Graph* MachineOperatorReducer::graph() const { return jsgraph()->graph(); }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8