From 6328df4fa23ba1279153fc381a3a3c456b41eef9 Mon Sep 17 00:00:00 2001
From: "vitalyr@chromium.org"
 <vitalyr@chromium.org@ce2b1a6d-e550-0410-aec6-3dcde31c8c00>
Date: Tue, 29 Jun 2010 13:48:20 +0000
Subject: [PATCH] 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               |  2 +-
 test/cctest/SConscript        |  3 ++-
 test/cctest/test-type-info.cc | 56 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 59 insertions(+), 2 deletions(-)
 create mode 100644 test/cctest/test-type-info.cc

diff --git a/src/type-info.h b/src/type-info.h
index 9d20bc1..91ecab8 100644
--- a/src/type-info.h
+++ b/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);
diff --git a/test/cctest/SConscript b/test/cctest/SConscript
index 876c104..18388c0 100644
--- a/test/cctest/SConscript
+++ b/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'
diff --git a/test/cctest/test-type-info.cc b/test/cctest/test-type-info.cc
new file mode 100644
index 0000000..59dd83d
--- /dev/null
+++ b/test/cctest/test-type-info.cc
@@ -0,0 +1,56 @@
+// 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
-- 
2.7.4