diff --git a/src/runtime.cc b/src/runtime.cc
index ccb88851b8..13f6561e32 100644
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -1750,10 +1750,10 @@ static Object* StringReplaceRegExpWithString(String* subject,
   // Index of end of last match.
   int prev = 0;
 
-  // Number of parts added by compiled replacement plus preceeding string
-  // and possibly suffix after last match. It is possible for compiled
-  // replacements to use two elements when encoded as two smis.
-  const int parts_added_per_loop = compiled_replacement.parts() * 2 + 2;
+  // Number of parts added by compiled replacement plus preceeding
+  // string and possibly suffix after last match.  It is possible for
+  // all components to use two elements when encoded as two smis.
+  const int parts_added_per_loop = 2 * (compiled_replacement.parts() + 2);
   bool matched = true;
   do {
     ASSERT(last_match_info_handle->HasFastElements());
diff --git a/test/mjsunit/regress/regress-515.js b/test/mjsunit/regress/regress-515.js
new file mode 100644
index 0000000000..7675fe19ed
--- /dev/null
+++ b/test/mjsunit/regress/regress-515.js
@@ -0,0 +1,40 @@
+// Copyright 2009 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.
+
+// Regression test for http://code.google.com/p/v8/issues/detail?id=515.
+//
+// The test passes if it does not crash.
+
+var length = 2048;
+var s = "";
+for (var i = 0; i < 2048; i++) {
+  s += '.';
+}
+
+var string = s + 'x' + s + 'x' + s;
+
+string.replace(/x/g, "")