Elide hole checks on KeyedLoads of holey double arrays.

test/mjsunit/elide-double-hole-check-1.js

Index: test/mjsunit/elide-double-hole-check-1.js
diff --git a/test/mjsunit/elide-double-hole-check-1.js b/test/mjsunit/elide-double-hole-check-1.js
new file mode 100644
index 0000000000000000000000000000000000000000..63569df294816ae355f92f678b2a5fad1d72c7dd
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+++ b/test/mjsunit/elide-double-hole-check-1.js
@@ -0,0 +1,52 @@
+// Copyright 2013 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.
+
+// Flags: --allow-natives-syntax
+
+function f1(a, i) {
+  return a[i]
+}
+
+var a1 = [,,,,,,,,,,,,,,,,,,0.5];
+assertEquals(undefined, f1(a1, 1));
+assertEquals(undefined, f1(a1, 1));
+%OptimizeFunctionOnNextCall(f1);
+assertEquals(undefined, f1(a1, 1));
+assertEquals(undefined, f1(a1, 1));
+
+function f2(a, i) {
+  return a[i] + 0.5;
+}
+var a2_b = [0.0,,];
+assertEquals(0.5, f2(a2_b, 0));
+assertEquals(0.5, f2(a2_b, 0));
+%OptimizeFunctionOnNextCall(f2);
+assertEquals(0.5, f2(a2_b, 0));
+assertEquals(NaN, f2(a2_b, 1));
+a2_b.__proto__ = [1.5,1.5,1.5];
+assertEquals(2, f2(a2_b, 1));
+assertEquals(0.5, f2(a2_b, 0));