Type info: fix three bit representation of smi type.

Review URL: http://codereview.chromium.org/2802022

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4976 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/type-info.h

@@ -79,7 +79,7 @@ class TypeInfo {
 
   // Decode compact representation.  Very sensitive to enum values below!
   static TypeInfo ExpandedRepresentation(int three_bit_representation) {
-    Type t = static_cast<Type>(three_bit_representation >= 6 ?
+    Type t = static_cast<Type>(three_bit_representation > 4 ?
                                three_bit_representation + 2 :
                                three_bit_representation);
     t = (t == kUnknownType) ? t : static_cast<Type>(t | kPrimitiveType);

test/cctest/SConscript

@@ -69,8 +69,9 @@ SOURCES = {
     'test-sockets.cc',
     'test-spaces.cc',
     'test-strings.cc',
-    'test-threads.cc',
     'test-thread-termination.cc',
+    'test-threads.cc',
+    'test-type-info.cc',
     'test-unbound-queue.cc',
     'test-utils.cc',
     'test-version.cc'

test/cctest/test-type-info.cc

+// Copyright 2010 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+#include "cctest.h"
+#include "type-info.h"
+
+namespace v8 {
+namespace internal {
+
+TEST(ThreeBitRepresentation) {
+  // Numeric types and unknown should fit into the short
+  // representation.
+  CHECK(TypeInfo::ExpandedRepresentation(
+      TypeInfo::Unknown().ThreeBitRepresentation()).IsUnknown());
+  CHECK(TypeInfo::ExpandedRepresentation(
+      TypeInfo::Number().ThreeBitRepresentation()).IsNumber());
+  CHECK(TypeInfo::ExpandedRepresentation(
+      TypeInfo::Integer32().ThreeBitRepresentation()).IsInteger32());
+  CHECK(TypeInfo::ExpandedRepresentation(
+      TypeInfo::Smi().ThreeBitRepresentation()).IsSmi());
+  CHECK(TypeInfo::ExpandedRepresentation(
+      TypeInfo::Double().ThreeBitRepresentation()).IsDouble());
+
+  // Other types should map to unknown.
+  CHECK(TypeInfo::ExpandedRepresentation(
+      TypeInfo::Primitive().ThreeBitRepresentation()).IsUnknown());
+  CHECK(TypeInfo::ExpandedRepresentation(
+      TypeInfo::String().ThreeBitRepresentation()).IsUnknown());
+}
+
+} }  // namespace v8::internal