Fix V8 issue 580: Arithmetic on some integer constants gives wrong anwers.

Review URL: http://codereview.chromium.org/545134

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3664 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/x64/codegen-x64.cc

@@ -6205,19 +6205,17 @@ void ToBooleanStub::Generate(MacroAssembler* masm) {
 
 
 bool CodeGenerator::FoldConstantSmis(Token::Value op, int left, int right) {
-  // TODO(X64): This method is identical to the ia32 version.
-  // Either find a reason to change it, or move it somewhere where it can be
-  // shared. (Notice: It assumes that a Smi can fit in an int).
-
   Object* answer_object = Heap::undefined_value();
   switch (op) {
     case Token::ADD:
-      if (Smi::IsValid(left + right)) {
+      // Use intptr_t to detect overflow of 32-bit int.
+      if (Smi::IsValid(static_cast<intptr_t>(left) + right)) {
         answer_object = Smi::FromInt(left + right);
       }
       break;
     case Token::SUB:
-      if (Smi::IsValid(left - right)) {
+      // Use intptr_t to detect overflow of 32-bit int.
+      if (Smi::IsValid(static_cast<intptr_t>(left) - right)) {
         answer_object = Smi::FromInt(left - right);
       }
       break;

test/mjsunit/regress/regress-580.js

+// 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.
+
+// Test constant folding of smi operations that overflow a 32-bit int
+// See http://code.google.com/p/v8/issues/detail?id=580
+
+function num_ops() {
+  var x;
+  var tmp = 0;
+  x = (tmp = 1578221999, tmp)+(tmp = 572285336, tmp);
+  assertEquals(2150507335, x);
+  x = 1578221999 + 572285336;
+  assertEquals(2150507335, x);
+
+  x = (tmp = -1500000000, tmp)+(tmp = -2000000000, tmp);
+  assertEquals(-3500000000, x);
+  x = -1500000000 + -2000000000;
+  assertEquals(-3500000000, x);
+
+  x = (tmp = 1578221999, tmp)-(tmp = -572285336, tmp);
+  assertEquals(2150507335, x);
+  x = 1578221999 - -572285336;
+  assertEquals(2150507335, x);
+
+  x = (tmp = -1500000000, tmp)-(tmp = 2000000000, tmp);
+  assertEquals(-3500000000, x);
+  x = -1500000000 - 2000000000;
+  assertEquals(-3500000000, x);
+}
+
+num_ops();