PPC: [turbofan] Implemented the optional Float32RoundTruncate operator.

src/compiler/ppc/instruction-selector-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/base/adapters.h"
 #include "src/compiler/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties.h"
 #include "src/ppc/frames-ppc.h"
 
@@ skipping 1141 matching lines @@
   VisitRR(this, kPPC_CeilDouble, node);
 }
 
 
 void InstructionSelector::VisitFloat64RoundUp(Node* node) {
   VisitRR(this, kPPC_CeilDouble, node);
 }
 
 
 void InstructionSelector::VisitFloat32RoundTruncate(Node* node) {
-  UNREACHABLE();
+  VisitRR(this, kPPC_TruncateDouble, node);
 }
 
 
 void InstructionSelector::VisitFloat64RoundTruncate(Node* node) {
   VisitRR(this, kPPC_TruncateDouble, node);
 }
 
 
 void InstructionSelector::VisitFloat64RoundTiesAway(Node* node) {
   VisitRR(this, kPPC_RoundDouble, node);
@@ skipping 511 matching lines @@
 }
 
 
 // static
 MachineOperatorBuilder::Flags
 InstructionSelector::SupportedMachineOperatorFlags() {
   return MachineOperatorBuilder::kFloat32RoundDown |
          MachineOperatorBuilder::kFloat64RoundDown |
          MachineOperatorBuilder::kFloat32RoundUp |
          MachineOperatorBuilder::kFloat64RoundUp |
+         MachineOperatorBuilder::kFloat32RoundTruncate |
          MachineOperatorBuilder::kFloat64RoundTruncate |
          MachineOperatorBuilder::kFloat64RoundTiesAway |
          MachineOperatorBuilder::kWord32Popcnt |
          MachineOperatorBuilder::kWord64Popcnt;
   // We omit kWord32ShiftIsSafe as s[rl]w use 0x3f as a mask rather than 0x1f.
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8