MIPS64: [turbofan] Implemented the TruncateFloat64ToUint64 TurboFan operator.

src/mips64/macro-assembler-mips64.h

Index: src/mips64/macro-assembler-mips64.h
diff --git a/src/mips64/macro-assembler-mips64.h b/src/mips64/macro-assembler-mips64.h
index 908788bc09838cf4be55bf97e1130f4d81bf58aa..be6f7e4c9174c3f1c665586bfa2e573b5da586b2 100644
--- a/src/mips64/macro-assembler-mips64.h
+++ b/src/mips64/macro-assembler-mips64.h
@@ -842,6 +842,10 @@ class MacroAssembler: public Assembler {
   void Trunc_uw_d(FPURegister fd, FPURegister fs, FPURegister scratch);
   void Trunc_uw_d(FPURegister fd, Register rs, FPURegister scratch);
 
+  // Convert double to unsigned long.
+  void Trunc_ul_d(FPURegister fd, FPURegister fs, FPURegister scratch);
+  void Trunc_ul_d(FPURegister fd, Register rs, FPURegister scratch);
+
   void Trunc_w_d(FPURegister fd, FPURegister fs);
   void Round_w_d(FPURegister fd, FPURegister fs);
   void Floor_w_d(FPURegister fd, FPURegister fs);