[turbofan] Change TruncateFloat32ToInt64 to TryTruncateFloat32ToInt64.

src/compiler/mips64/instruction-selector-mips64.cc

Index: src/compiler/mips64/instruction-selector-mips64.cc
diff --git a/src/compiler/mips64/instruction-selector-mips64.cc b/src/compiler/mips64/instruction-selector-mips64.cc
index 4e56b0726d447ef6d709e8108bff13b21668078e..25149db0a55704a9f2accde0bcf283e27467a6b7 100644
--- a/src/compiler/mips64/instruction-selector-mips64.cc
+++ b/src/compiler/mips64/instruction-selector-mips64.cc
@@ -850,8 +850,19 @@ void InstructionSelector::VisitChangeFloat64ToUint32(Node* node) {
 }
 
 
-void InstructionSelector::VisitTruncateFloat32ToInt64(Node* node) {
-  VisitRR(this, kMips64TruncLS, node);
+void InstructionSelector::VisitTryTruncateFloat32ToInt64(Node* node) {
+  Mips64OperandGenerator g(this);
+  InstructionOperand inputs[] = {g.UseRegister(node->InputAt(0))};
+  InstructionOperand outputs[2];
+  size_t output_count = 0;
+  outputs[output_count++] = g.DefineAsRegister(node);
+
+  Node* success_output = NodeProperties::FindProjection(node, 1);
+  if (success_output) {
+    outputs[output_count++] = g.DefineAsRegister(success_output);
+  }
+
+  this->Emit(kMips64TruncLS, output_count, outputs, 1, inputs);
 }
 
 
@@ -1529,6 +1540,8 @@ void VisitWordCompareZero(InstructionSelector* selector, Node* user,
               case IrOpcode::kInt32SubWithOverflow:
                 cont->OverwriteAndNegateIfEqual(kOverflow);
                 return VisitBinop(selector, node, kMips64Dsub, cont);
+              case IrOpcode::kTryTruncateFloat32ToInt64:

[titzer, 2015/12/09 11:40:35]

Drop this case as per explanation on other CL.

+                return VisitTryTruncFloat32ToInt64(selector, result);
               default:
                 break;
             }