[turbofan] Weakening of types must handle ranges inside unions.

test/cctest/test-types.cc

Index: test/cctest/test-types.cc
diff --git a/test/cctest/test-types.cc b/test/cctest/test-types.cc
index e564c6c0808ab20f29d0fde37b12380d55343dcf..ad4660735928e384b7b986d9d5f8c2f5d8e3e2f9 100644
--- a/test/cctest/test-types.cc
+++ b/test/cctest/test-types.cc
@@ -1831,6 +1831,48 @@ struct Tests : Rep {
     */
   }
 
+  TypeHandle RangeToHandle(typename Type::RangeType* range) {

[rossberg, 2014/11/12 14:51:15]

That seems a bit hacky. Can we instead have a proper generic handlify function
inherited from the respective Rep classes?

+    return T.Range(range->Min(), range->Max());
+  }
+
+  void GetRange() {
+    // GetRange(Range(a, b)) = Range(a, b).
+    for (TypeIterator it1 = T.types.begin(); it1 != T.types.end(); ++it1) {
+      TypeHandle type1 = *it1;
+      if (type1->IsRange()) {
+        typename Type::RangeType* range = type1->GetRange();
+        CHECK(type1->Equals(RangeToHandle(range)));
+      }
+    }
+
+    // GetRange(Union(Constant(x), Range(min,max))) == Range(min, max).
+    for (TypeIterator it1 = T.types.begin(); it1 != T.types.end(); ++it1) {
+      for (TypeIterator it2 = T.types.begin(); it2 != T.types.end(); ++it2) {
+        TypeHandle type1 = *it1;
+        TypeHandle type2 = *it2;
+        if (type1->IsConstant() && type2->IsRange()) {
+          TypeHandle u = T.Union(type1, type2);
+
+          CHECK(type2->Equals(RangeToHandle(u->GetRange())));
+        }
+      }
+    }
+
+    // GetRange is monotone whenever it is defined.
+    for (TypeIterator it1 = T.types.begin(); it1 != T.types.end(); ++it1) {
+      for (TypeIterator it2 = T.types.begin(); it2 != T.types.end(); ++it2) {
+        TypeHandle type1 = *it1;
+        TypeHandle type2 = *it2;
+        if (type1->GetRange() != NULL && type2->GetRange() != NULL &&
+            type1->Is(type2)) {
+          TypeHandle r1 = RangeToHandle(type1->GetRange());
+          TypeHandle r2 = RangeToHandle(type2->GetRange());
+          CHECK(r1->Is(r2));
+        }
+      }
+    }
+  }
+
   template<class Type2, class TypeHandle2, class Region2, class Rep2>
   void Convert() {
     Types<Type2, TypeHandle2, Region2> T2(
@@ -2030,6 +2072,13 @@ TEST(Distributivity) {
 }
 
 
+TEST(GetRange) {
+  CcTest::InitializeVM();
+  ZoneTests().GetRange();
+  HeapTests().GetRange();
+}
+
+
 TEST(Convert) {
   CcTest::InitializeVM();
   ZoneTests().Convert<HeapType, Handle<HeapType>, Isolate, HeapRep>();