[turbofan] Implemented the ChangeFloat64ToInt64 TurboFan operator.

src/compiler/ppc/code-generator-ppc.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/code-generator.h"
 
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/osr.h"
@@ skipping 1111 matching lines @@
       __ ConvertIntToDouble(i.InputRegister(0), i.OutputDoubleRegister());
       DCHECK_EQ(LeaveRC, i.OutputRCBit());
       break;
     case kPPC_Uint32ToDouble:
       __ ConvertUnsignedIntToDouble(i.InputRegister(0),
                                     i.OutputDoubleRegister());
       DCHECK_EQ(LeaveRC, i.OutputRCBit());
       break;
     case kPPC_DoubleToInt32:
     case kPPC_DoubleToUint32:
+    case kPPC_DoubleToInt64:
       __ ConvertDoubleToInt64(i.InputDoubleRegister(0),
 #if !V8_TARGET_ARCH_PPC64
                               kScratchReg,
 #endif
                               i.OutputRegister(), kScratchDoubleReg);
       DCHECK_EQ(LeaveRC, i.OutputRCBit());
       break;
     case kPPC_DoubleToFloat32:
       ASSEMBLE_FLOAT_UNOP_RC(frsp);
       break;
@@ skipping 592 matching lines @@
       padding_size -= v8::internal::Assembler::kInstrSize;
     }
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8