Use a stub in crankshaft for grow store arrays.

test/mjsunit/ensure-growing-store-learns.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.
+
+// Flags: --allow-natives-syntax --noverify-heap
+
+// --noverify-heap is set because the test is too slow with it on.
+
+// Ensure that keyed stores work, and optimized functions learn if the
+// store required change to dictionary mode. Verify that stores that grow
+// the array into large object space don't cause a deopt.
+(function() {
+  var a = [];
+
+  function foo(a, i) {
+    a[i] = 5.3;
+  }
+
+  foo(a, 1);
+  foo(a, 2);
+  foo(a, 3);
+  %OptimizeFunctionOnNextCall(foo);
+  a[3] = 0;
+  foo(a, 3);
+  assertEquals(a[3], 5.3);
+  foo(a, 50000);
+  assertUnoptimized(foo);
+  assertTrue(%HasDictionaryElements(a));
+
+  var b = [];
+  foo(b, 1);
+  foo(b, 2);
+  // Put b in dictionary mode.
+  b[10000] = 5;
+  assertTrue(%HasDictionaryElements(b));
+  foo(b, 3);
+  %OptimizeFunctionOnNextCall(foo);
+  foo(b, 50000);
+  assertOptimized(foo);
+  assertTrue(%HasDictionaryElements(b));
+})();
+
+
+(function() {
+  var a = new Array(10);
+
+  function foo2(a, i) {
+    a[i] = 50;
+  }
+
+  // The KeyedStoreIC will learn GROW_MODE.
+  foo2(a, 10);
+  foo2(a, 12);
+  foo2(a, 31);
+  %OptimizeFunctionOnNextCall(foo2);
+  foo2(a, 40);
+  assertOptimized(foo2);
+  assertTrue(%HasFastSmiElements(a));
+
+  // Grow a large array into large object space through the keyed store
+  // without deoptimizing. Grow by 10s. If we set elements too sparsely, the 
+  // array will convert to dictionary mode.
+  a = new Array(99999);
+  assertTrue(%HasFastSmiElements(a));
+  for (var i = 0; i < 263000; i += 10) {
+    foo2(a, i);
+  }
+
+  // Verify that we are over 1 page in size, and foo2 remains optimized.
+  // This means we've smoothly transitioned to allocating in large object
+  // space.
+  assertTrue(%HasFastSmiElements(a));
+  assertTrue(a.length * 4 > (1024 * 1024));
+  assertOptimized(foo2);
+})();
+
+
+// Verify that it works with non-arrays too.
+(function() {
+  // Get an object to create a fast elements array. It takes some effort.
+  var o = {};
+  function foo(a, i) {
+    a[i] = 50;
+  }
+  assertTrue(%HasFastSmiOrObjectElements(o));
+
+  foo(o, 0);
+  foo(o, 1);
+  %OptimizeFunctionOnNextCall(foo);
+  // 16 should be enough to make the elements array grow, but not go to
+  // dictionary mode.
+  foo(o, 16);
+  assertOptimized(foo);
+  foo(o, 32000);
+  assertUnoptimized(foo);
+  assertTrue(%HasDictionaryElements(o));
+})();