Extend JSBuiltinReducer to cover Math.sqrt as well.

src/compiler/simplified-lowering.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/simplified-lowering.h"
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
 #include "src/compiler/common-operator.h"
 #include "src/compiler/graph-inl.h"
@@ skipping 704 matching lines @@
       case IrOpcode::kChangeFloat64ToUint32:
         return VisitUnop(node, kTypeUint32 | kRepFloat64,
                          kTypeUint32 | kRepWord32);
 
       case IrOpcode::kFloat64Add:
       case IrOpcode::kFloat64Sub:
       case IrOpcode::kFloat64Mul:
       case IrOpcode::kFloat64Div:
       case IrOpcode::kFloat64Mod:
         return VisitFloat64Binop(node);
+      case IrOpcode::kFloat64Sqrt:
+        return VisitUnop(node, kMachFloat64, kMachFloat64);
       case IrOpcode::kFloat64Equal:
       case IrOpcode::kFloat64LessThan:
       case IrOpcode::kFloat64LessThanOrEqual:
         return VisitFloat64Cmp(node);
       default:
         VisitInputs(node);
         break;
     }
   }
 
@@ skipping 195 matching lines @@
 void SimplifiedLowering::DoStringLessThanOrEqual(Node* node) {
   node->set_op(machine()->IntLessThanOrEqual());
   node->ReplaceInput(0, StringComparison(node, true));
   node->ReplaceInput(1, jsgraph()->SmiConstant(EQUAL));
 }
 
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8