Track representations of fields

test/mjsunit/track-fields.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: --track-fields --track-double-fields --allow-natives-syntax
+
+// Test transitions caused by changes to field representations.
+
+function create_smi_object() {
+  var o = {};
+  o.x = 1;
+  o.y = 2;
+  o.z = 3;
+  return o;
+}
+
+var o1 = create_smi_object();
+var o2 = create_smi_object();
+
+// o1,o2 are smi, smi, smi
+assertTrue(%HaveSameMap(o1, o2));
+o1.y = 1.3;
+// o1 is smi, double, smi
+assertFalse(%HaveSameMap(o1, o2));
+o2.y = 1.5;
+// o2 is smi, double, smi
+assertTrue(%HaveSameMap(o1, o2));
+
+// o3 is initialized as smi, double, smi
+var o3 = create_smi_object();
+assertTrue(%HaveSameMap(o1, o3));
+
+function set_large(o, v) {
+  o.x01 = v; o.x02 = v; o.x03 = v; o.x04 = v; o.x05 = v; o.x06 = v; o.x07 = v;
+  o.x08 = v; o.x09 = v; o.x10 = v; o.x11 = v; o.x12 = v; o.x13 = v; o.x14 = v;
+  o.x15 = v; o.x16 = v; o.x17 = v; o.x18 = v; o.x19 = v; o.x20 = v; o.x21 = v;
+  o.x22 = v; o.x23 = v; o.x24 = v; o.x25 = v; o.x26 = v; o.x27 = v; o.x28 = v;
+  o.x29 = v; o.x30 = v; o.x31 = v; o.x32 = v; o.x33 = v; o.x34 = v; o.x35 = v;
+  o.x36 = v; o.x37 = v; o.x38 = v; o.x39 = v; o.x40 = v; o.x41 = v; o.x42 = v;
+  o.y01 = v; o.y02 = v; o.y03 = v; o.y04 = v; o.y05 = v; o.y06 = v; o.y07 = v;
+  o.y08 = v; o.y09 = v; o.y10 = v; o.y11 = v; o.y12 = v; o.y13 = v; o.y14 = v;
+  o.y15 = v; o.y16 = v; o.y17 = v; o.y18 = v; o.y19 = v; o.y20 = v; o.y21 = v;
+}
+
+// Check that large object migrations work.
+var o4 = {};
+// All smi.
+set_large(o4, 0);
+assertTrue(%HasFastProperties(o4));
+// All double.
+set_large(o4, 1.5);
+// o5 is immediately allocated with doubles.
+var o5 = {};
+set_large(o5, 0);
+assertTrue(%HaveSameMap(o4, o5));
+
+function create_smi_object2() {
+  var o = {};
+  o.a = 1;
+  o.b = 2;
+  o.c = 3;
+  return o;
+}
+
+// All smi
+var o6 = create_smi_object2();
+var o7 = create_smi_object2();
+
+assertTrue(%HaveSameMap(o6, o7));
+// Smi, double, smi.
+o6.b = 1.5;
+assertFalse(%HaveSameMap(o6, o7));
+// Smi, double, object.
+o7.c = {};
+assertFalse(%HaveSameMap(o6, o7));
+// Smi, double, object.
+o6.c = {};
+assertTrue(%HaveSameMap(o6, o7));