text: // 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: --allow-natives-syntax --expose-gc
  
  // Limit the number of stress runs to reduce polymorphism it defeats some of the
  // assumptions made about how elements transitions work because transition stubs
  // end up going generic.
  // Flags: --stress-runs=2
  
  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;
    // Every external kind is also an external array.
    assertTrue(%HasExternalArrayElements(obj));
    if (%HasExternalByteElements(obj)) {
      return elements_kind.external_byte;
    }
    if (%HasExternalUnsignedByteElements(obj)) {
      return elements_kind.external_unsigned_byte;
    }
    if (%HasExternalShortElements(obj)) {
      return elements_kind.external_short;
    }
    if (%HasExternalUnsignedShortElements(obj)) {
      return elements_kind.external_unsigned_short;
    }
    if (%HasExternalIntElements(obj)) {
      return elements_kind.external_int;
    }
    if (%HasExternalUnsignedIntElements(obj)) {
      return elements_kind.external_unsigned_int;
    }
    if (%HasExternalFloatElements(obj)) {
      return elements_kind.external_float;
    }
    if (%HasExternalDoubleElements(obj)) {
      return elements_kind.external_double;
    }
    if (%HasExternalPixelElements(obj)) {
      return elements_kind.external_pixel;
    }
  }
  
  function assertKind(expected, obj, name_opt) {
    assertEquals(expected, getKind(obj), name_opt);
  }
  
  %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(convert_mixed);
  function convert_mixed(array, value, kind) {
    array[1] = value;
    assertKind(kind, array);
    assertEquals(value, array[1]);
  }
  
  function test1() {
    // Test transition chain SMI->DOUBLE->FAST (crankshafted function will
    // transition to FAST directly).
    var smis = construct_smis();
    convert_mixed(smis, 1.5, elements_kind.fast_double);
  
    var doubles = construct_doubles();
    convert_mixed(doubles, "three", elements_kind.fast);
  
    convert_mixed(construct_smis(), "three", elements_kind.fast);
    convert_mixed(construct_doubles(), "three", elements_kind.fast);
  
    smis = construct_smis();
    doubles = construct_doubles();
    convert_mixed(smis, 1, elements_kind.fast);
    convert_mixed(doubles, 1, elements_kind.fast);
    assertTrue(%HaveSameMap(smis, doubles));
  }
  
  test1();
  gc(); // clear IC state
  test1();
  gc(); // clear IC state
  %OptimizeFunctionOnNextCall(test1);
  test1();
  gc(); // clear IC state
  