Allocation Info Tracking, continued.

test/mjsunit/allocation-site-info.js

 // 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 --expose-gc
-// Flags: --track-allocation-sites
+// Flags: --track-allocation-sites --nooptimize-constructed-arrays
+
+// TODO(mvstanton): remove --nooptimize-constructed-arrays and enable
+// the constructed array code below when the feature is turned on
+// by default.
 
 // 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.
 
 support_smi_only_arrays = %HasFastSmiElements(new Array(1,2,3,4,5,6,7,8));
+optimize_constructed_arrays = false;
 
 if (support_smi_only_arrays) {
   print("Tests include smi-only arrays.");
 } else {
   print("Tests do NOT include smi-only arrays.");
 }
 
+if (optimize_constructed_arrays) {
+  print("Tests include constructed array optimizations.");
+} else {
+  print("Tests do NOT include constructed array optimizations.");
+}
+
 var elements_kind = {
   fast_smi_only            :  'fast smi only elements',
   fast                     :  'fast elements',
   fast_double              :  'fast double elements',
   dictionary               :  'dictionary elements',
   external_byte            :  'external byte elements',
   external_unsigned_byte   :  'external unsigned byte elements',
   external_short           :  'external short elements',
   external_unsigned_short  :  'external unsigned short elements',
   external_int             :  'external int elements',
   external_unsigned_int    :  'external unsigned int elements',
   external_float           :  'external float elements',
   external_double          :  'external double elements',
   external_pixel           :  'external pixel elements'
 }
 
 function getKind(obj) {
   if (%HasFastSmiElements(obj)) return elements_kind.fast_smi_only;
   if (%HasFastObjectElements(obj)) return elements_kind.fast;
   if (%HasFastDoubleElements(obj)) return elements_kind.fast_double;
   if (%HasDictionaryElements(obj)) return elements_kind.dictionary;
 }
 
+function isHoley(obj) {
+  if (%HasFastHoleyElements(obj)) return true;
+  return false;
+}
+
 function assertKind(expected, obj, name_opt) {
   if (!support_smi_only_arrays &&
       expected == elements_kind.fast_smi_only) {
     expected = elements_kind.fast;
   }
   assertEquals(expected, getKind(obj), name_opt);
 }
 
+function assertHoley(obj, name_opt) {
+  assertEquals(true, isHoley(obj), name_opt);
+}
+
+function assertNotHoley(obj, name_opt) {
+  assertEquals(false, isHoley(obj), name_opt);
+}
+
 if (support_smi_only_arrays) {
+
+  obj = [];
+  assertNotHoley(obj);
+  assertKind(elements_kind.fast_smi_only, obj);
+
+  obj = [1, 2, 3];
+  assertNotHoley(obj);
+  assertKind(elements_kind.fast_smi_only, obj);
+
+  obj = new Array();
+  assertNotHoley(obj);
+  assertKind(elements_kind.fast_smi_only, obj);
+
+  obj = new Array(0);
+  assertNotHoley(obj);
+  assertKind(elements_kind.fast_smi_only, obj);
+
+  obj = new Array(2);
+  assertHoley(obj);
+  assertKind(elements_kind.fast_smi_only, obj);
+
+  obj = new Array(1,2,3);
+  assertNotHoley(obj);
+  assertKind(elements_kind.fast_smi_only, obj);
+
+  obj = new Array(1, "hi", 2, undefined);
+  assertNotHoley(obj);
+  assertKind(elements_kind.fast, obj);
+
   function fastliteralcase(literal, value) {
-    // var literal = [1, 2, 3];
     literal[0] = value;
     return literal;
   }
 
   function get_standard_literal() {
     var literal = [1, 2, 3];
     return literal;
   }
 
   // Case: [1,2,3] as allocation site
   obj = fastliteralcase(get_standard_literal(), 1);
   assertKind(elements_kind.fast_smi_only, obj);
   obj = fastliteralcase(get_standard_literal(), 1.5);
   assertKind(elements_kind.fast_double, obj);
   obj = fastliteralcase(get_standard_literal(), 2);
   assertKind(elements_kind.fast_double, obj);
 
   obj = fastliteralcase([5, 3, 2], 1.5);
   assertKind(elements_kind.fast_double, obj);
   obj = fastliteralcase([3, 6, 2], 1.5);
   assertKind(elements_kind.fast_double, obj);
   obj = fastliteralcase([2, 6, 3], 2);
   assertKind(elements_kind.fast_smi_only, obj);
 
   // Verify that we will not pretransition the double->fast path.
   obj = fastliteralcase(get_standard_literal(), "elliot");
   assertKind(elements_kind.fast, obj);
-
   // This fails until we turn off optimistic transitions to the
   // most general elements kind seen on keyed stores. It's a goal
   // to turn it off, but for now we need it.
   // obj = fastliteralcase(3);
   // assertKind(elements_kind.fast_double, obj);
 
   function fastliteralcase_smifast(value) {
     var literal = [1, 2, 3, 4];
     literal[0] = value;
     return literal;
   }
 
   obj = fastliteralcase_smifast(1);
   assertKind(elements_kind.fast_smi_only, obj);
   obj = fastliteralcase_smifast("carter");
   assertKind(elements_kind.fast, obj);
   obj = fastliteralcase_smifast(2);
   assertKind(elements_kind.fast, obj);
+
+  if (optimize_constructed_arrays) {
+    function newarraycase_smidouble(value) {
+      var a = new Array();
+      a[0] = value;
+      return a;
+    }
+
+    // Case: new Array() as allocation site, smi->double
+    obj = newarraycase_smidouble(1);
+    assertKind(elements_kind.fast_smi_only, obj);
+    obj = newarraycase_smidouble(1.5);
+    assertKind(elements_kind.fast_double, obj);
+    obj = newarraycase_smidouble(2);
+    assertKind(elements_kind.fast_double, obj);
+
+    function newarraycase_smiobj(value) {
+      var a = new Array();
+      a[0] = value;
+      return a;
+    }
+
+    // Case: new Array() as allocation site, smi->fast
+    obj = newarraycase_smiobj(1);
+    assertKind(elements_kind.fast_smi_only, obj);
+    obj = newarraycase_smiobj("gloria");
+    assertKind(elements_kind.fast, obj);
+    obj = newarraycase_smiobj(2);
+    assertKind(elements_kind.fast, obj);
+
+    function newarraycase_length_smidouble(value) {
+      var a = new Array(3);
+      a[0] = value;
+      return a;
+    }
+
+    // Case: new Array(length) as allocation site
+    obj = newarraycase_length_smidouble(1);
+    assertKind(elements_kind.fast_smi_only, obj);
+    obj = newarraycase_length_smidouble(1.5);
+    assertKind(elements_kind.fast_double, obj);
+    obj = newarraycase_length_smidouble(2);
+    assertKind(elements_kind.fast_double, obj);
+
+    // Try to continue the transition to fast object, but
+    // we will not pretransition from double->fast, because
+    // it may hurt performance ("poisoning").
+    obj = newarraycase_length_smidouble("coates");
+    assertKind(elements_kind.fast, obj);
+    obj = newarraycase_length_smidouble(2.5);
+    // However, because of optimistic transitions, we will
+    // transition to the most general kind of elements kind found,
+    // therefore I can't count on this assert yet.
+    // assertKind(elements_kind.fast_double, obj);
+
+    function newarraycase_length_smiobj(value) {
+      var a = new Array(3);
+      a[0] = value;
+      return a;
+    }
+
+    // Case: new Array(<length>) as allocation site, smi->fast
+    obj = newarraycase_length_smiobj(1);
+    assertKind(elements_kind.fast_smi_only, obj);
+    obj = newarraycase_length_smiobj("gloria");
+    assertKind(elements_kind.fast, obj);
+    obj = newarraycase_length_smiobj(2);
+    assertKind(elements_kind.fast, obj);
+
+    function newarraycase_list_smidouble(value) {
+      var a = new Array(1, 2, 3);
+      a[0] = value;
+      return a;
+    }
+
+    obj = newarraycase_list_smidouble(1);
+    assertKind(elements_kind.fast_smi_only, obj);
+    obj = newarraycase_list_smidouble(1.5);
+    assertKind(elements_kind.fast_double, obj);
+    obj = newarraycase_list_smidouble(2);
+    assertKind(elements_kind.fast_double, obj);
+
+    function newarraycase_list_smiobj(value) {
+      var a = new Array(4, 5, 6);
+      a[0] = value;
+      return a;
+    }
+
+    obj = newarraycase_list_smiobj(1);
+    assertKind(elements_kind.fast_smi_only, obj);
+    obj = newarraycase_list_smiobj("coates");
+    assertKind(elements_kind.fast, obj);
+    obj = newarraycase_list_smiobj(2);
+    assertKind(elements_kind.fast, obj);
+  }
 }