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

src/compiler/mips64/instruction-codes-mips64.h

 // 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.
 
 #ifndef V8_COMPILER_MIPS_INSTRUCTION_CODES_MIPS_H_
 #define V8_COMPILER_MIPS_INSTRUCTION_CODES_MIPS_H_
 
 namespace v8 {
 namespace internal {
 namespace compiler {
@@ skipping 56 matching lines @@
   V(Mips64MaxD)                     \
   V(Mips64MinD)                     \
   V(Mips64Float64RoundDown)         \
   V(Mips64Float64RoundTruncate)     \
   V(Mips64Float64RoundUp)           \
   V(Mips64CvtSD)                    \
   V(Mips64CvtDS)                    \
   V(Mips64TruncWD)                  \
   V(Mips64TruncUwD)                 \
   V(Mips64CvtDW)                    \
+  V(Mips64CvtSL)                    \
   V(Mips64CvtDL)                    \
   V(Mips64CvtDUw)                   \
   V(Mips64Lb)                       \
   V(Mips64Lbu)                      \
   V(Mips64Sb)                       \
   V(Mips64Lh)                       \
   V(Mips64Lhu)                      \
   V(Mips64Sh)                       \
   V(Mips64Ld)                       \
   V(Mips64Lw)                       \
@@ skipping 36 matching lines @@
 #define TARGET_ADDRESSING_MODE_LIST(V) \
   V(MRI) /* [%r0 + K] */               \
   V(MRR) /* [%r0 + %r1] */
 
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_MIPS_INSTRUCTION_CODES_MIPS_H_