[turbofan] Take type into account when determining Word32 phi representation.

BUG=
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/968913002

Cr-Commit-Position: refs/heads/master@{#26958}

src/compiler/simplified-lowering.cc

@@ -329,7 +329,8 @@ class RepresentationSelector {
       } else if (upper->Is(Type::Signed32()) || upper->Is(Type::Unsigned32())) {
         // multiple uses, but we are within 32 bits range => pick kRepWord32.
         return kRepWord32;
-      } else if ((use & kRepMask) == kRepWord32 ||
+      } else if (((use & kRepMask) == kRepWord32 &&
+                  !CanObserveNonWord32(use)) ||
                  (use & kTypeMask) == kTypeInt32 ||
                  (use & kTypeMask) == kTypeUint32) {
         // We only use 32 bits or we use the result consistently.
@@ -456,6 +457,10 @@ class RepresentationSelector {
            !CanObserveNonUint32(use);
   }
 
+  bool CanObserveNonWord32(MachineTypeUnion use) {
+    return (use & ~(kTypeUint32 | kTypeInt32)) != 0;
+  }
+
   bool CanObserveNonInt32(MachineTypeUnion use) {
     return (use & (kTypeUint32 | kTypeNumber | kTypeAny)) != 0;
   }

test/mjsunit/mjsunit.status

@@ -108,11 +108,6 @@
   'es6/debug-stepin-microtasks': [PASS, NO_VARIANTS],
   'es6/debug-stepnext-for': [PASS, NO_VARIANTS],
   'harmony/debug-evaluate-blockscopes': [PASS, NO_VARIANTS],
-
-  # TODO(jarin): Some tests don't like --turbo-deoptimzation very much.
-  'asm/embenchen/lua_binarytrees': [SKIP],
-  'es6/symbols': [PASS, NO_VARIANTS],
-  'regress/regress-354433': [PASS, NO_VARIANTS],  # only on ARM simulator.
   'regress/regress-crbug-259300': [PASS, NO_VARIANTS],
 
   ##############################################################################