[turbofan] Add operators for float32 support.

src/compiler/machine-operator-reducer.cc

Index: src/compiler/machine-operator-reducer.cc
diff --git a/src/compiler/machine-operator-reducer.cc b/src/compiler/machine-operator-reducer.cc
index 936deca8b636deb3e1121cfb9cb360c6a23fc842..53ee81075e960875e0a9d94de8dc0247744e732d 100644
--- a/src/compiler/machine-operator-reducer.cc
+++ b/src/compiler/machine-operator-reducer.cc
@@ -21,6 +21,11 @@ MachineOperatorReducer::MachineOperatorReducer(JSGraph* jsgraph)
 MachineOperatorReducer::~MachineOperatorReducer() {}
 
 
+Node* MachineOperatorReducer::Float32Constant(volatile float value) {
+  return graph()->NewNode(common()->Float32Constant(value));
+}
+
+
 Node* MachineOperatorReducer::Float64Constant(volatile double value) {
   return jsgraph()->Float64Constant(value);
 }
@@ -383,6 +388,11 @@ Reduction MachineOperatorReducer::Reduce(Node* node) {
       }
       break;
     }
+    case IrOpcode::kChangeFloat32ToFloat64: {
+      Float32Matcher m(node->InputAt(0));
+      if (m.HasValue()) return ReplaceFloat64(m.Value());
+      break;
+    }
     case IrOpcode::kChangeFloat64ToInt32: {
       Float64Matcher m(node->InputAt(0));
       if (m.HasValue()) return ReplaceInt32(FastD2I(m.Value()));
@@ -427,6 +437,12 @@ Reduction MachineOperatorReducer::Reduce(Node* node) {
       if (m.IsChangeInt32ToInt64()) return Replace(m.node()->InputAt(0));
       break;
     }
+    case IrOpcode::kTruncateFloat64ToFloat32: {
+      Float64Matcher m(node->InputAt(0));
+      if (m.HasValue()) return ReplaceFloat32(DoubleToFloat32(m.Value()));
+      if (m.IsChangeFloat32ToFloat64()) return Replace(m.node()->InputAt(0));
+      break;
+    }
     // TODO(turbofan): strength-reduce and fold floating point operations.
     default:
       break;