[turbofan] Add support for reinterpreting integers as floating point and vice versa.

src/compiler/x64/instruction-selector-x64.cc

Index: src/compiler/x64/instruction-selector-x64.cc
diff --git a/src/compiler/x64/instruction-selector-x64.cc b/src/compiler/x64/instruction-selector-x64.cc
index fa63138f2799841c5af49c2ac93a7493541881cb..516a9a7691ca0d7c2ba9c33a47857bc07dec48e3 100644
--- a/src/compiler/x64/instruction-selector-x64.cc
+++ b/src/compiler/x64/instruction-selector-x64.cc
@@ -906,6 +906,30 @@ void InstructionSelector::VisitTruncateInt64ToInt32(Node* node) {
 }
 
 
+void InstructionSelector::VisitBitcastFloat32ToInt32(Node* node) {
+  X64OperandGenerator g(this);
+  Emit(kX64BitcastFI, g.DefineAsRegister(node), g.Use(node->InputAt(0)));
+}
+
+
+void InstructionSelector::VisitBitcastFloat64ToInt64(Node* node) {
+  X64OperandGenerator g(this);
+  Emit(kX64BitcastDL, g.DefineAsRegister(node), g.Use(node->InputAt(0)));
+}
+
+
+void InstructionSelector::VisitBitcastInt32ToFloat32(Node* node) {
+  X64OperandGenerator g(this);
+  Emit(kX64BitcastIF, g.DefineAsRegister(node), g.Use(node->InputAt(0)));
+}
+
+
+void InstructionSelector::VisitBitcastInt64ToFloat64(Node* node) {
+  X64OperandGenerator g(this);
+  Emit(kX64BitcastLD, g.DefineAsRegister(node), g.Use(node->InputAt(0)));
+}
+
+
 void InstructionSelector::VisitFloat32Add(Node* node) {
   VisitFloatBinop(this, node, kAVXFloat32Add, kSSEFloat32Add);
 }