text: // 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 --expose-gc --nostress-opt --typed-array-max_size_in-heap=2048
  
  var elements_kind = {
    fast_smi_only             :  'fast smi only elements',
    fast                      :  'fast elements',
    fast_double               :  'fast double elements',
    dictionary                :  'dictionary elements',
    external_int32            :  'external int8 elements',
    external_uint8            :  'external uint8 elements',
    external_int16            :  'external int16 elements',
    external_uint16           :  'external uint16 elements',
    external_int32            :  'external int32 elements',
    external_uint32           :  'external uint32 elements',
    external_float32          :  'external float32 elements',
    external_float64          :  'external float64 elements',
    external_uint8_clamped    :  'external uint8_clamped elements',
    fixed_int32               :  'fixed int8 elements',
    fixed_uint8               :  'fixed uint8 elements',
    fixed_int16               :  'fixed int16 elements',
    fixed_uint16              :  'fixed uint16 elements',
    fixed_int32               :  'fixed int32 elements',
    fixed_uint32              :  'fixed uint32 elements',
    fixed_float32             :  'fixed float32 elements',
    fixed_float64             :  'fixed float64 elements',
    fixed_uint8_clamped       :  'fixed uint8_clamped 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;
  
    // Every external kind is also an external array.
    if (%HasExternalInt8Elements(obj)) {
      return elements_kind.external_int8;
    }
    if (%HasExternalUint8Elements(obj)) {
      return elements_kind.external_uint8;
    }
    if (%HasExternalInt16Elements(obj)) {
      return elements_kind.external_int16;
    }
    if (%HasExternalUint16Elements(obj)) {
      return elements_kind.external_uint16;
    }
    if (%HasExternalInt32Elements(obj)) {
      return elements_kind.external_int32;
    }
    if (%HasExternalUint32Elements(obj)) {
      return elements_kind.external_uint32;
    }
    if (%HasExternalFloat32Elements(obj)) {
      return elements_kind.external_float32;
    }
    if (%HasExternalFloat64Elements(obj)) {
      return elements_kind.external_float64;
    }
    if (%HasExternalUint8ClampedElements(obj)) {
      return elements_kind.external_uint8_clamped;
    }
    if (%HasFixedInt8Elements(obj)) {
      return elements_kind.fixed_int8;
    }
    if (%HasFixedUint8Elements(obj)) {
      return elements_kind.fixed_uint8;
    }
    if (%HasFixedInt16Elements(obj)) {
      return elements_kind.fixed_int16;
    }
    if (%HasFixedUint16Elements(obj)) {
      return elements_kind.fixed_uint16;
    }
    if (%HasFixedInt32Elements(obj)) {
      return elements_kind.fixed_int32;
    }
    if (%HasFixedUint32Elements(obj)) {
      return elements_kind.fixed_uint32;
    }
    if (%HasFixedFloat32Elements(obj)) {
      return elements_kind.fixed_float32;
    }
    if (%HasFixedFloat64Elements(obj)) {
      return elements_kind.fixed_float64;
    }
    if (%HasFixedUint8ClampedElements(obj)) {
      return elements_kind.fixed_uint8_clamped;
    }
  }
  
  function assertKind(expected, obj, name_opt) {
    assertEquals(expected, getKind(obj), name_opt);
  }
  
  var me = {};
  assertKind(elements_kind.fast, me);
  me.dance = 0xD15C0;
  me.drink = 0xC0C0A;
  assertKind(elements_kind.fast, me);
  
  var too = [1,2,3];
  assertKind(elements_kind.fast_smi_only, too);
  too.dance = 0xD15C0;
  too.drink = 0xC0C0A;
  assertKind(elements_kind.fast_smi_only, too);
  
  // Make sure the element kind transitions from smi when a non-smi is stored.
  function test_wrapper() {
    var you = new Array();
    assertKind(elements_kind.fast_smi_only, you);
    for (var i = 0; i < 1337; i++) {
      var val = i;
      if (i == 1336) {
        assertKind(elements_kind.fast_smi_only, you);
        val = new Object();
      }
      you[i] = val;
    }
    assertKind(elements_kind.fast, you);
  
    assertKind(elements_kind.dictionary, new Array(0xDECAF));
  
    var fast_double_array = new Array(0xDECAF);
    for (var i = 0; i < 0xDECAF; i++) fast_double_array[i] = i / 2;
    assertKind(elements_kind.fast_double, fast_double_array);
  
    assertKind(elements_kind.fixed_int8,    new Int8Array(007));
    assertKind(elements_kind.fixed_uint8,   new Uint8Array(007));
    assertKind(elements_kind.fixed_int16,   new Int16Array(666));
    assertKind(elements_kind.fixed_uint16,  new Uint16Array(42));
    assertKind(elements_kind.fixed_int32,   new Int32Array(0xF));
    assertKind(elements_kind.fixed_uint32,  new Uint32Array(23));
    assertKind(elements_kind.fixed_float32, new Float32Array(7));
    assertKind(elements_kind.fixed_float64, new Float64Array(0));
    assertKind(elements_kind.fixed_uint8_clamped, new Uint8ClampedArray(512));
  
    var ab = new ArrayBuffer(128);
    assertKind(elements_kind.external_int8,    new Int8Array(ab));
    assertKind(elements_kind.external_uint8,   new Uint8Array(ab));
    assertKind(elements_kind.external_int16,   new Int16Array(ab));
    assertKind(elements_kind.external_uint16,  new Uint16Array(ab));
    assertKind(elements_kind.external_int32,   new Int32Array(ab));
    assertKind(elements_kind.external_uint32,  new Uint32Array(ab));
    assertKind(elements_kind.external_float32, new Float32Array(ab));
    assertKind(elements_kind.external_float64, new Float64Array(ab));
    assertKind(elements_kind.external_uint8_clamped, new Uint8ClampedArray(ab));
  
    // Crankshaft support for smi-only array elements.
    function monomorphic(array) {
      assertKind(elements_kind.fast_smi_only, array);
      for (var i = 0; i < 3; i++) {
        array[i] = i + 10;
      }
      assertKind(elements_kind.fast_smi_only, array);
      for (var i = 0; i < 3; i++) {
        var a = array[i];
        assertEquals(i + 10, a);
      }
    }
    var smi_only = new Array(1, 2, 3);
    assertKind(elements_kind.fast_smi_only, smi_only);
    for (var i = 0; i < 3; i++) monomorphic(smi_only);
      %OptimizeFunctionOnNextCall(monomorphic);
    monomorphic(smi_only);
  }
  
  // The test is called in a wrapper function to eliminate the transition learning
  // feedback of AllocationSites.
  test_wrapper();
  %ClearFunctionTypeFeedback(test_wrapper);
  
  %NeverOptimizeFunction(construct_smis);
  
  // This code exists to eliminate the learning influence of AllocationSites
  // on the following tests.
  var __sequence = 0;
  function make_array_string() {
    this.__sequence = this.__sequence + 1;
    return "/* " + this.__sequence + " */  [0, 0, 0];"
  }
  function make_array() {
    return eval(make_array_string());
  }
  
  function construct_smis() {
    var a = make_array();
    a[0] = 0;  // Send the COW array map to the steak house.
    assertKind(elements_kind.fast_smi_only, a);
    return a;
  }
    %NeverOptimizeFunction(construct_doubles);
  function construct_doubles() {
    var a = construct_smis();
    a[0] = 1.5;
    assertKind(elements_kind.fast_double, a);
    return a;
  }
    %NeverOptimizeFunction(construct_objects);
  function construct_objects() {
    var a = construct_smis();
    a[0] = "one";
    assertKind(elements_kind.fast, a);
    return a;
  }
  
  // Test crankshafted transition SMI->DOUBLE.
    %NeverOptimizeFunction(convert_to_double);
  function convert_to_double(array) {
    array[1] = 2.5;
    assertKind(elements_kind.fast_double, array);
    assertEquals(2.5, array[1]);
  }
  var smis = construct_smis();
  for (var i = 0; i < 3; i++) convert_to_double(smis);
    %OptimizeFunctionOnNextCall(convert_to_double);
  smis = construct_smis();
  convert_to_double(smis);
  // Test crankshafted transitions SMI->FAST and DOUBLE->FAST.
    %NeverOptimizeFunction(convert_to_fast);
  function convert_to_fast(array) {
    array[1] = "two";
    assertKind(elements_kind.fast, array);
    assertEquals("two", array[1]);
  }
  smis = construct_smis();
  for (var i = 0; i < 3; i++) convert_to_fast(smis);
  var doubles = construct_doubles();
  for (var i = 0; i < 3; i++) convert_to_fast(doubles);
  smis = construct_smis();
  doubles = construct_doubles();
    %OptimizeFunctionOnNextCall(convert_to_fast);
  convert_to_fast(smis);
  convert_to_fast(doubles);
  // Test transition chain SMI->DOUBLE->FAST (crankshafted function will
  // transition to FAST directly).
    %NeverOptimizeFunction(convert_mixed);
  function convert_mixed(array, value, kind) {
    array[1] = value;
    assertKind(kind, array);
    assertEquals(value, array[1]);
  }
  smis = construct_smis();
  for (var i = 0; i < 3; i++) {
    convert_mixed(smis, 1.5, elements_kind.fast_double);
  }
  doubles = construct_doubles();
  for (var i = 0; i < 3; i++) {
    convert_mixed(doubles, "three", elements_kind.fast);
  }
  convert_mixed(construct_smis(), "three", elements_kind.fast);
  convert_mixed(construct_doubles(), "three", elements_kind.fast);
    %OptimizeFunctionOnNextCall(convert_mixed);
  smis = construct_smis();
  doubles = construct_doubles();
  convert_mixed(smis, 1, elements_kind.fast);
  convert_mixed(doubles, 1, elements_kind.fast);
  assertTrue(%HaveSameMap(smis, doubles));
  
  // Crankshaft support for smi-only elements in dynamic array literals.
  function get(foo) { return foo; }  // Used to generate dynamic values.
  
  function crankshaft_test() {
    var a1 = [get(1), get(2), get(3)];
    assertKind(elements_kind.fast_smi_only, a1);
  
    var a2 = new Array(get(1), get(2), get(3));
    assertKind(elements_kind.fast_smi_only, a2);
    var b = [get(1), get(2), get("three")];
    assertKind(elements_kind.fast, b);
    var c = [get(1), get(2), get(3.5)];
    assertKind(elements_kind.fast_double, c);
  }
  for (var i = 0; i < 3; i++) {
    crankshaft_test();
  }
  %OptimizeFunctionOnNextCall(crankshaft_test);
  crankshaft_test();
  
  // Elements_kind transitions for arrays.
  
  // A map can have three different elements_kind transitions: SMI->DOUBLE,
  // DOUBLE->OBJECT, and SMI->OBJECT. No matter in which order these three are
  // created, they must always end up with the same FAST map.
  
  // Preparation: create one pair of identical objects for each case.
  var a = [1, 2, 3];
  var b = [1, 2, 3];
  assertTrue(%HaveSameMap(a, b));
  assertKind(elements_kind.fast_smi_only, a);
  var c = [1, 2, 3];
  c["case2"] = true;
  var d = [1, 2, 3];
  d["case2"] = true;
  assertTrue(%HaveSameMap(c, d));
  assertFalse(%HaveSameMap(a, c));
  assertKind(elements_kind.fast_smi_only, c);
  var e = [1, 2, 3];
  e["case3"] = true;
  var f = [1, 2, 3];
  f["case3"] = true;
  assertTrue(%HaveSameMap(e, f));
  assertFalse(%HaveSameMap(a, e));
  assertFalse(%HaveSameMap(c, e));
  assertKind(elements_kind.fast_smi_only, e);
  // Case 1: SMI->DOUBLE, DOUBLE->OBJECT, SMI->OBJECT.
  a[0] = 1.5;
  assertKind(elements_kind.fast_double, a);
  a[0] = "foo";
  assertKind(elements_kind.fast, a);
  b[0] = "bar";
  assertTrue(%HaveSameMap(a, b));
  // Case 2: SMI->DOUBLE, SMI->OBJECT, DOUBLE->OBJECT.
  c[0] = 1.5;
  assertKind(elements_kind.fast_double, c);
  assertFalse(%HaveSameMap(c, d));
  d[0] = "foo";
  assertKind(elements_kind.fast, d);
  assertFalse(%HaveSameMap(c, d));
  c[0] = "bar";
  assertTrue(%HaveSameMap(c, d));
  // Case 3: SMI->OBJECT, SMI->DOUBLE, DOUBLE->OBJECT.
  e[0] = "foo";
  assertKind(elements_kind.fast, e);
  assertFalse(%HaveSameMap(e, f));
  f[0] = 1.5;
  assertKind(elements_kind.fast_double, f);
  assertFalse(%HaveSameMap(e, f));
  f[0] = "bar";
  assertKind(elements_kind.fast, f);
  assertTrue(%HaveSameMap(e, f));
  
  // Test if Array.concat() works correctly with DOUBLE elements.
  var a = [1, 2];
  assertKind(elements_kind.fast_smi_only, a);
  var b = [4.5, 5.5];
  assertKind(elements_kind.fast_double, b);
  var c = a.concat(b);
  assertEquals([1, 2, 4.5, 5.5], c);
  assertKind(elements_kind.fast_double, c);
  
  // Test that Array.push() correctly handles SMI elements.
  var a = [1, 2];
  assertKind(elements_kind.fast_smi_only, a);
  a.push(3, 4, 5);
  assertKind(elements_kind.fast_smi_only, a);
  assertEquals([1, 2, 3, 4, 5], a);
  
  // Test that Array.splice() and Array.slice() return correct ElementsKinds.
  var a = ["foo", "bar"];
  assertKind(elements_kind.fast, a);
  var b = a.splice(0, 1);
  assertKind(elements_kind.fast, b);
  var c = a.slice(0, 1);
  assertKind(elements_kind.fast, c);
  
  // Throw away type information in the ICs for next stress run.
  gc();
  