Fix for bug 245480. Calling new Array(a) with a single argument could

test/mjsunit/regress/regress-crbug-245480.js

 // 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 --nodead-code-elimination
-// Flags: --nofold-constants --nouse-gvn
+// Flags: --allow-natives-syntax --smi-only-arrays --expose-gc
+// Flags: --track-allocation-sites --noalways-opt
 
-// Create a function to get a long series of removable simulates.
-// f() {
-//   var _0 = <random>, _1 = <random>, ... _1000 = <random>,
-//   _1001 = <random var> + <random var>,
-//   _1002 = <random var> + <random var>,
-//   ...
-//   _99999 = <random var> + <random var>,
-//   x = 1;
-//   return _0;
-// }
+// Test element kind of objects.
+// Since --smi-only-arrays affects builtins, its default setting at compile
+// time sticks if built with snapshot.  If --smi-only-arrays is deactivated
+// by default, only a no-snapshot build actually has smi-only arrays enabled
+// in this test case.  Depending on whether smi-only arrays are actually
+// enabled, this test takes the appropriate code path to check smi-only arrays.
 
-var seed = 1;
+// support_smi_only_arrays = %HasFastSmiElements(new Array(1,2,3,4,5,6,7,8));
+support_smi_only_arrays = true;
 
-function rand() {
-  seed = seed * 171 % 1337 + 17;
-  return (seed % 1000) / 1000;
+if (support_smi_only_arrays) {
+  print("Tests include smi-only arrays.");
+} else {
+  print("Tests do NOT include smi-only arrays.");
 }
 
-function randi(max) {
-  seed = seed * 131 % 1773 + 13;
-  return seed % max;
+function isHoley(obj) {
+  if (%HasFastHoleyElements(obj)) return true;
+  return false;
 }
 
-function varname(i) {
-  return "_" + i;
+function assertHoley(obj, name_opt) {
+  assertEquals(true, isHoley(obj), name_opt);
 }
 
-var source = "var ";
-
-for (var i = 0; i < 1000; i++) {
-  source += [varname(i), "=", rand(), ","].join("");
+function assertNotHoley(obj, name_opt) {
+  assertEquals(false, isHoley(obj), name_opt);
 }
 
-for (var i = 1000; i < 100000; i++) {
-  source += [varname(i), "=",
-             varname(randi(i)), "+",
-             varname(randi(i)), ","].join("");
+if (support_smi_only_arrays) {
+  function create_array(arg) {
+    return new Array(arg);
+  }
+
+  obj = create_array(0);
+  assertNotHoley(obj);
+  create_array(0);
+  %OptimizeFunctionOnNextCall(create_array);
+  obj = create_array(10);
+  assertHoley(obj);
 }
 
-source += "x=1; return _0;"
-var f = new Function(source);
+// The code below would assert in debug or crash in release
+function f(length) {
+  return new Array(length)
+}
 
-f();
+f(0);
+f(0);
 %OptimizeFunctionOnNextCall(f);
-f();
+var a = f(10);
 
+function g(a) {
+  return a[0];
+}
+
+var b = [0];
+g(b);
+g(b);
+assertEquals(undefined, g(a));