Implement tracking and optimizations of packed arrays

test/mjsunit/packed-elements.js

Index: test/mjsunit/packed-elements.js
diff --git a/test/mjsunit/packed-elements.js b/test/mjsunit/packed-elements.js
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+// Copyright 2012 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 --smi-only-arrays

[Jakob Kummerow, 2012/05/13 21:55:27]

Might want to specify --packed-arrays here too ;-)

[danno, 2012/05/22 11:05:21]

Done.

+
+var has_packed_elements = !%HasFastHoleyElements([]);
+
+function test1() {
+  var a = Array(8);
+  assertTrue(%HasFastSmiOrObjectElements(a));
+  assertTrue(%HasFastHoleyElements(a));
+}
+
+function test2() {
+  var a = Array();
+  assertTrue(%HasFastSmiOrObjectElements(a));
+  assertFalse(%HasFastHoleyElements(a));
+}
+
+function test3() {
+  var a = Array(1,2,3,4,5,6,7);
+  assertTrue(%HasFastSmiOrObjectElements(a));
+  assertFalse(%HasFastHoleyElements(a));
+}
+
+function test4() {
+  var a = [1, 2, 3, 4];
+  assertTrue(%HasFastSmiElements(a));
+  assertFalse(%HasFastHoleyElements(a));
+  var b = [1, 2,, 4];
+  assertTrue(%HasFastSmiElements(b));
+  assertTrue(%HasFastHoleyElements(b));
+}
+
+function test5() {
+  var a = [1, 2, 3, 4.5];
+  assertTrue(%HasFastDoubleElements(a));
+  assertFalse(%HasFastHoleyElements(a));
+  var b = [1,, 3.5, 4];
+  assertTrue(%HasFastDoubleElements(b));
+  assertTrue(%HasFastHoleyElements(b));
+  var c = [1, 3.5,, 4];
+  assertTrue(%HasFastDoubleElements(c));
+  assertTrue(%HasFastHoleyElements(c));
+}
+
+function test6() {
+  var x = new Object();
+  var a = [1, 2, 3.5, x];
+  assertTrue(%HasFastObjectElements(a));
+  assertFalse(%HasFastHoleyElements(a));
+  assertEquals(1, a[0]);
+  assertEquals(2, a[1]);
+  assertEquals(3.5, a[2]);
+  assertEquals(x, a[3]);
+  var b = [1,, 3.5, x];
+  assertTrue(%HasFastObjectElements(b));
+  assertTrue(%HasFastHoleyElements(b));
+  assertEquals(1, b[0]);
+  assertEquals(undefined, b[1]);
+  assertEquals(3.5, b[2]);
+  assertEquals(x, b[3]);
+  var c = [1, 3.5, x,,];
+  assertTrue(%HasFastObjectElements(c));
+  assertTrue(%HasFastHoleyElements(c));
+  assertEquals(1, c[0]);
+  assertEquals(3.5, c[1]);
+  assertEquals(x, c[2]);
+  assertEquals(undefined, c[3]);
+}
+
+function test_with_optimization(f) {
+  // Run tests in a loop to make sure that inlined Array() constructor runs out
+  // of new space memory and must fall back on runtime impl.
+  for (i = 0; i < 250000; ++i) f();
+  %OptimizeFunctionOnNextCall(f);
+  for (i = 0; i < 250000; ++i) f(); // Make sure GC happens
+}
+
+if (has_packed_elements) {
+  test_with_optimization(test1);
+  test_with_optimization(test2);
+  test_with_optimization(test3);
+  test_with_optimization(test4);
+  test_with_optimization(test5);
+  test_with_optimization(test6);
+}
+