[turbofan] Add backend support for float32.

test/cctest/compiler/test-representation-change.cc

Index: test/cctest/compiler/test-representation-change.cc
diff --git a/test/cctest/compiler/test-representation-change.cc b/test/cctest/compiler/test-representation-change.cc
index 6c9026b2e018ee7147b684239fbd3fc516249902..b49157e3d0f21ffc4a19a2c55a4a696d9ca57ee2 100644
--- a/test/cctest/compiler/test-representation-change.cc
+++ b/test/cctest/compiler/test-representation-change.cc
@@ -89,8 +89,8 @@ class RepresentationChangerTester : public HandleAndZoneScope,
 
 
 // TODO(titzer): add kRepFloat32 when fully supported.
-static const MachineType all_reps[] = {kRepBit, kRepWord32, kRepWord64,
-                                       kRepFloat64, kRepTagged};
+static const MachineType all_reps[] = {kRepBit,     kRepWord32,  kRepWord64,
+                                       kRepFloat32, kRepFloat64, kRepTagged};
 
 
 // TODO(titzer): lift this to ValueHelper
@@ -295,11 +295,4 @@ TEST(TypeErrors) {
       r.CheckTypeError(all_reps[i] | all_reps[j], kRepTagged);
     }
   }
-
-  // TODO(titzer): Float32 representation changes trigger type errors now.
-  // Enforce current behavior to test all paths through representation changer.
-  for (size_t i = 0; i < arraysize(all_reps); i++) {
-    r.CheckTypeError(all_reps[i], kRepFloat32);
-    r.CheckTypeError(kRepFloat32, all_reps[i]);
-  }
 }