PPC: [turbofan] Prevent storing signalling NaNs into holey double arrays.

src/compiler/ppc/instruction-scheduler-ppc.cc

 // Copyright 2015 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/instruction-scheduler.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
@@ skipping 74 matching lines @@
     case kPPC_Int64ToInt32:
     case kPPC_Int64ToFloat32:
     case kPPC_Int64ToDouble:
     case kPPC_Uint64ToFloat32:
     case kPPC_Uint64ToDouble:
     case kPPC_Int32ToFloat32:
     case kPPC_Int32ToDouble:
     case kPPC_Uint32ToFloat32:
     case kPPC_Uint32ToDouble:
     case kPPC_Float32ToDouble:
+    case kPPC_Float64SilenceNaN:
     case kPPC_DoubleToInt32:
     case kPPC_DoubleToUint32:
     case kPPC_DoubleToInt64:
     case kPPC_DoubleToUint64:
     case kPPC_DoubleToFloat32:
     case kPPC_DoubleExtractLowWord32:
     case kPPC_DoubleExtractHighWord32:
     case kPPC_DoubleInsertLowWord32:
     case kPPC_DoubleInsertHighWord32:
     case kPPC_DoubleConstruct:
@@ skipping 38 matching lines @@
 
 
 int InstructionScheduler::GetInstructionLatency(const Instruction* instr) {
   // TODO(all): Add instruction cost modeling.
   return 1;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8