Migrated several tests from blink to V8 repository.

test/webkit/dfg-get-by-val-clobber.js

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions
 // are met:
 // 1.  Redistributions of source code must retain the above copyright
 //     notice, this list of conditions and the following disclaimer.
 // 2.  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.
 //
 // THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS 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 APPLE INC. OR ITS 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.
 
 description(
-"Tests the behavior of Array.prototype.concat while the array is having a bad time due to one of the elements we are concatenating."
+"This tests that common subexpression elimination knows how to accurately model PutBuVal."
 );
 
-Object.defineProperty(Array.prototype, 0, { writable: false });
-shouldBe("[42].concat()", "[42]");
+function doAccesses(a, b, i, j, y) {
+    var x = a[i];
+    b[j] = y;
+    return a[i];
+}
 
+var array1 = [1, 2, 3, 4];
+var array2 = [5, 6, 7, 8];
 
+for (var i = 0; i < 1000; ++i) {
+    // Simple test, pretty easy to pass.
+    shouldBe("doAccesses(array1, array2, i % 4, (i + 1) % 4, i)", "" + ((i % 4) + 1));
+    shouldBe("array2[" + ((i + 1) % 4) + "]", "" + i);
+
+    // Undo.
+    array2[((i + 1) % 4)] = (i % 4) + 5;
+
+    // Now the evil test. This is constructed to minimize the likelihood that CSE will succeed through
+    // cleverness alone.
+    shouldBe("doAccesses(array1, array1, i % 4, 0, i)", "" + ((i % 4) == 0 ? i : (i % 4) + 1));
+
+    // Undo.
+    array1[0] = 1;
+}
+