[turbofan] Add backend support for float32.

src/compiler/ia32/instruction-selector-ia32.cc

Index: src/compiler/ia32/instruction-selector-ia32.cc
diff --git a/src/compiler/ia32/instruction-selector-ia32.cc b/src/compiler/ia32/instruction-selector-ia32.cc
index 24ebc38393cd1e2e972a4996e891ed8ec9bfa64b..dfdf23329ba4a70057c7acea329d91621973d37e 100644
--- a/src/compiler/ia32/instruction-selector-ia32.cc
+++ b/src/compiler/ia32/instruction-selector-ia32.cc
@@ -354,6 +354,13 @@ void InstructionSelector::VisitInt32UMod(Node* node) {
 }
 
 
+void InstructionSelector::VisitChangeFloat32ToFloat64(Node* node) {
+  IA32OperandGenerator g(this);
+  // TODO(turbofan): IA32 SSE conversions should take an operand.
+  Emit(kSSECvtss2sd, g.DefineAsRegister(node), g.UseRegister(node->InputAt(0)));
+}
+
+
 void InstructionSelector::VisitChangeInt32ToFloat64(Node* node) {
   IA32OperandGenerator g(this);
   Emit(kSSEInt32ToFloat64, g.DefineAsRegister(node), g.Use(node->InputAt(0)));
@@ -380,6 +387,13 @@ void InstructionSelector::VisitChangeFloat64ToUint32(Node* node) {
 }
 
 
+void InstructionSelector::VisitTruncateFloat64ToFloat32(Node* node) {
+  IA32OperandGenerator g(this);
+  // TODO(turbofan): IA32 SSE conversions should take an operand.
+  Emit(kSSECvtsd2ss, g.DefineAsRegister(node), g.UseRegister(node->InputAt(0)));
+}
+
+
 void InstructionSelector::VisitFloat64Add(Node* node) {
   IA32OperandGenerator g(this);
   Emit(kSSEFloat64Add, g.DefineSameAsFirst(node),