Implemented the RoundInt64ToFloat32 TurboFan operator for x64, arm64, and mips64.

src/compiler/machine-operator.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.h"
 
 #include "src/base/lazy-instance.h"
 #include "src/compiler/opcodes.h"
 #include "src/compiler/operator.h"
 
@@ skipping 114 matching lines @@
   V(Int64LessThan, Operator::kNoProperties, 2, 0, 1)                          \
   V(Int64LessThanOrEqual, Operator::kNoProperties, 2, 0, 1)                   \
   V(Uint64Div, Operator::kNoProperties, 2, 1, 1)                              \
   V(Uint64Mod, Operator::kNoProperties, 2, 1, 1)                              \
   V(Uint64LessThan, Operator::kNoProperties, 2, 0, 1)                         \
   V(Uint64LessThanOrEqual, Operator::kNoProperties, 2, 0, 1)                  \
   V(ChangeFloat32ToFloat64, Operator::kNoProperties, 1, 0, 1)                 \
   V(ChangeFloat64ToInt32, Operator::kNoProperties, 1, 0, 1)                   \
   V(ChangeFloat64ToUint32, Operator::kNoProperties, 1, 0, 1)                  \
   V(ChangeInt32ToFloat64, Operator::kNoProperties, 1, 0, 1)                   \
+  V(RoundInt64ToFloat32, Operator::kNoProperties, 1, 0, 1)                    \
   V(RoundInt64ToFloat64, Operator::kNoProperties, 1, 0, 1)                    \
   V(ChangeInt32ToInt64, Operator::kNoProperties, 1, 0, 1)                     \
   V(ChangeUint32ToFloat64, Operator::kNoProperties, 1, 0, 1)                  \
   V(ChangeUint32ToUint64, Operator::kNoProperties, 1, 0, 1)                   \
   V(TruncateFloat64ToFloat32, Operator::kNoProperties, 1, 0, 1)               \
   V(TruncateInt64ToInt32, Operator::kNoProperties, 1, 0, 1)                   \
   V(BitcastFloat32ToInt32, Operator::kNoProperties, 1, 0, 1)                  \
   V(BitcastFloat64ToInt64, Operator::kNoProperties, 1, 0, 1)                  \
   V(BitcastInt32ToFloat32, Operator::kNoProperties, 1, 0, 1)                  \
   V(BitcastInt64ToFloat64, Operator::kNoProperties, 1, 0, 1)                  \
@@ skipping 233 matching lines @@
     default:
       break;
   }
   UNREACHABLE();
   return nullptr;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8