[turbofan] Fix Typer::Rangify to handle integral bitset types.

src/compiler/typer.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/bootstrapper.h"
 #include "src/compiler/graph-inl.h"
 #include "src/compiler/js-operator.h"
 #include "src/compiler/node.h"
 #include "src/compiler/node-properties-inl.h"
 #include "src/compiler/node-properties.h"
@@ skipping 390 matching lines @@
 
 
 Type* Typer::Visitor::FalsifyUndefined(Type* type, Typer* t) {
   if (type->Is(Type::Undefined())) return t->singleton_false;
   return type;
 }
 
 
 Type* Typer::Visitor::Rangify(Type* type, Typer* t) {
   if (type->IsRange()) return type;        // Shortcut.
-  if (!type->Is(t->integer)) return type;  // Give up.
+  if (!type->Is(t->integer) && !type->Is(Type::Integral32())) {
+    return type;  // Give up on non-integer types.
+  }
+  double min = type->Min();
+  double max = type->Max();
+  // Handle the degenerate case of empty bitset types (such as
+  // OtherUnsigned31 and OtherSigned32 on 64-bit architectures).
+  if (std::isnan(min)) {
+    DCHECK(std::isnan(max));
+    return type;
+  }
   Factory* f = t->isolate()->factory();
-  return Type::Range(f->NewNumber(type->Min()), f->NewNumber(type->Max()),
-                     t->zone());
+  return Type::Range(f->NewNumber(min), f->NewNumber(max), t->zone());
 }
 
 
 // Type conversion.
 
 
 Type* Typer::Visitor::ToPrimitive(Type* type, Typer* t) {
   if (type->Is(Type::Primitive()) && !type->Maybe(Type::Receiver())) {
     return type;
   }
@@ skipping 1457 matching lines @@
         return typer_->float64_array_fun_;
       }
     }
   }
   return Type::Constant(value, zone());
 }
 
 }
 }
 }  // namespace v8::internal::compiler