test/mjsunit/track-fields.js - v8/v8.git - Git at Google

 // 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));

 function poly_load(o, b) {
   var v = o.field;
   if (b) {
     return v + 10;
   }
   return o;
 }

 var of1 = {a:0};
 of1.field = {};
 var of2 = {b:0};
 of2.field = 10;

 poly_load(of1, false);
 poly_load(of1, false);
 poly_load(of2, true);
 %OptimizeFunctionOnNextCall(poly_load);
 assertEquals("[object Object]10", poly_load(of1, true));

 // Ensure small object literals with doubles do not share double storage.
 function object_literal() { return {"a":1.5}; }
 var o8 = object_literal();
 var o9 = object_literal();
 o8.a = 4.6
 assertEquals(1.5, o9.a);

 // Ensure double storage is not leaked in the case of polymorphic loads.
 function load_poly(o) {
   return o.a;
 }

 var o10 = { "a": 1.6 };
 var o11 = { "b": 1, "a": 1.7 };
 load_poly(o10);
 load_poly(o10);
 load_poly(o11);
 %OptimizeFunctionOnNextCall(load_poly);
 var val = load_poly(o10);
 o10.a = 19.5;
 assertFalse(o10.a == val);

 // Ensure polymorphic loads only go monomorphic when the representations are
 // compatible.

 // Check polymorphic load from double + object fields.
 function load_mono(o) {
   return o.a1;
 }

 var object = {"x": 1};
 var o10 = { "a1": 1.6 };
 var o11 = { "a1": object, "b": 1 };
 load_mono(o10);
 load_mono(o10);
 load_mono(o11);
 %OptimizeFunctionOnNextCall(load_mono);
 assertEquals(object, load_mono(o11));

 // Check polymorphic load from smi + object fields.
 function load_mono2(o) {
   return o.a2;
 }

 var o12 = { "a2": 5 };
 var o13 = { "a2": object, "b": 1 };
 load_mono2(o12);
 load_mono2(o12);
 load_mono2(o13);
 %OptimizeFunctionOnNextCall(load_mono2);
 assertEquals(object, load_mono2(o13));

 // Check polymorphic load from double + double fields.
 function load_mono3(o) {
   return o.a3;
 }

 var o14 = { "a3": 1.6 };
 var o15 = { "a3": 1.8, "b": 1 };
 load_mono3(o14);
 load_mono3(o14);
 load_mono3(o15);
 %OptimizeFunctionOnNextCall(load_mono3);
 assertEquals(1.6, load_mono3(o14));
 assertEquals(1.8, load_mono3(o15));

 // Check that JSON parsing respects existing representations.
 var o16 = JSON.parse('{"a":1.5}');
 var o17 = JSON.parse('{"a":100}');
 assertTrue(%HaveSameMap(o16, o17));
 var o17_a = o17.a;
 assertEquals(100, o17_a);
 o17.a = 200;
 assertEquals(100, o17_a);
 assertEquals(200, o17.a);

 // Ensure normalizing results in ignored representations.
 var o18 = {};
 o18.field1 = 100;
 o18.field2 = 1;
 o18.to_delete = 100;

 var o19 = {};
 o19.field1 = 100;
 o19.field2 = 1.6;
 o19.to_delete = 100;

 assertFalse(%HaveSameMap(o18, o19));

 delete o18.to_delete;
 delete o19.to_delete;

 assertEquals(1, o18.field2);
 assertEquals(1.6, o19.field2);

 // Test megamorphic keyed stub behaviour in combination with representations.
 var some_object20 = {"a":1};
 var o20 = {};
 o20.smi = 1;
 o20.dbl = 1.5;
 o20.obj = some_object20;

 function keyed_load(o, k) {
   return o[k];
 }

 function keyed_store(o, k, v) {
   return o[k] = v;
 }

 var smi20 = keyed_load(o20, "smi");
 var dbl20 = keyed_load(o20, "dbl");
 var obj20 = keyed_load(o20, "obj");
 keyed_load(o20, "smi");
 keyed_load(o20, "dbl");
 keyed_load(o20, "obj");
 keyed_load(o20, "smi");
 keyed_load(o20, "dbl");
 keyed_load(o20, "obj");

 assertEquals(1, smi20);
 assertEquals(1.5, dbl20);
 assertEquals(some_object20, obj20);

 keyed_store(o20, "smi", 100);
 keyed_store(o20, "dbl", 100);
 keyed_store(o20, "obj", 100);
 keyed_store(o20, "smi", 100);
 keyed_store(o20, "dbl", 100);
 keyed_store(o20, "obj", 100);
 keyed_store(o20, "smi", 100);
 keyed_store(o20, "dbl", 100);
 keyed_store(o20, "obj", 100);

 assertEquals(1, smi20);
 assertEquals(1.5, dbl20);
 assertEquals(some_object20, obj20);

 assertEquals(100, o20.smi);
 assertEquals(100, o20.dbl);
 assertEquals(100, o20.dbl);

 function attr_mismatch_obj(v, writable) {
   var o = {};
   // Assign twice to make the field non-constant.
   // TODO(ishell): update test once constant field tracking is done.
   o.some_value = 0;
   o.some_value = v;
   Object.defineProperty(o, "second_value", {value:10, writable:writable});
   return o;
 }

 function is_writable(o, p) {
   return Object.getOwnPropertyDescriptor(o,p).writable;
 }

 var writable = attr_mismatch_obj(10, true);
 var non_writable1 = attr_mismatch_obj(10.5, false);
 assertTrue(is_writable(writable,"second_value"));
 assertFalse(is_writable(non_writable1,"second_value"));
 writable.some_value = 20.5;
 assertTrue(is_writable(writable,"second_value"));
 var non_writable2 = attr_mismatch_obj(10.5, false);
 assertTrue(%HaveSameMap(non_writable1, non_writable2));

 function test_f(v) {
   var o = {};
   o.vbf = v;
   o.func = test_f;
   return o;
 }

 function test_fic(o) {
   return o.vbf;
 }

 var ftest1 = test_f(10);
 var ftest2 = test_f(10);
 var ftest3 = test_f(10.5);
 var ftest4 = test_f(10);
 assertFalse(%HaveSameMap(ftest1, ftest3));
 assertTrue(%HaveSameMap(ftest3, ftest4));
 ftest2.func = is_writable;
 test_fic(ftest1);
 test_fic(ftest2);
 test_fic(ftest3);
 test_fic(ftest4);
 assertTrue(%HaveSameMap(ftest1, ftest3));
 assertTrue(%HaveSameMap(ftest3, ftest4));

 // Test representations and transition conversions.
 function read_first_double(o) {
   return o.first_double;
 }
 var df1 = {};
 df1.first_double=1.6;
 read_first_double(df1);
 read_first_double(df1);
 function some_function1() { return 10; }
 var df2 = {};
 df2.first_double = 1.7;
 df2.second_function = some_function1;
 function some_function2() { return 20; }
 var df3 = {};
 df3.first_double = 1.7;
 df3.second_function = some_function2;
 df1.first_double = 10;
 read_first_double(df1);

 // Test boilerplates with computed values.
 function none_boilerplate(a) {
   return {"a_none":a};
 }
 %OptimizeFunctionOnNextCall(none_boilerplate);
 var none_double1 = none_boilerplate(1.7);
 var none_double2 = none_boilerplate(1.9);
 assertTrue(%HaveSameMap(none_double1, none_double2));
 assertEquals(1.7, none_double1.a_none);
 assertEquals(1.9, none_double2.a_none);
 none_double2.a_none = 3.5;
 var none_double1 = none_boilerplate(1.7);
 var none_double2 = none_boilerplate(3.5);

 function none_to_smi(a) {
   return {"a_smi":a};
 }

 var none_smi1 = none_to_smi(1);
 var none_smi2 = none_to_smi(2);
 %OptimizeFunctionOnNextCall(none_to_smi);
 var none_smi3 = none_to_smi(3);
 assertTrue(%HaveSameMap(none_smi1, none_smi2));
 assertTrue(%HaveSameMap(none_smi1, none_smi3));
 assertEquals(1, none_smi1.a_smi);
 assertEquals(2, none_smi2.a_smi);
 assertEquals(3, none_smi3.a_smi);

 function none_to_double(a) {
   return {"a_double":a};
 }

 var none_to_double1 = none_to_double(1.5);
 var none_to_double2 = none_to_double(2.8);
 %OptimizeFunctionOnNextCall(none_to_double);
 var none_to_double3 = none_to_double(3.7);
 assertTrue(%HaveSameMap(none_to_double1, none_to_double2));
 assertTrue(%HaveSameMap(none_to_double1, none_to_double3));
 assertEquals(1.5, none_to_double1.a_double);
 assertEquals(2.8, none_to_double2.a_double);
 assertEquals(3.7, none_to_double3.a_double);

 function none_to_object(a) {
   return {"an_object":a};
 }

 var none_to_object1 = none_to_object(true);
 var none_to_object2 = none_to_object(false);
 %OptimizeFunctionOnNextCall(none_to_object);
 var none_to_object3 = none_to_object(3.7);
 assertTrue(%HaveSameMap(none_to_object1, none_to_object2));
 assertTrue(%HaveSameMap(none_to_object1, none_to_object3));
 assertEquals(true, none_to_object1.an_object);
 assertEquals(false, none_to_object2.an_object);
 assertEquals(3.7, none_to_object3.an_object);

 function double_to_object(a) {
   var o = {"d_to_h":1.8};
   o.d_to_h = a;
   return o;
 }

 var dh1 = double_to_object(true);
 var dh2 = double_to_object(false);
 assertTrue(%HaveSameMap(dh1, dh2));
 assertEquals(true, dh1.d_to_h);
 assertEquals(false, dh2.d_to_h);

 function smi_to_object(a) {
   var o = {"s_to_t":18};
   o.s_to_t = a;
   return o;
 }

 var st1 = smi_to_object(true);
 var st2 = smi_to_object(false);
 assertTrue(%HaveSameMap(st1, st2));
 assertEquals(true, st1.s_to_t);
 assertEquals(false, st2.s_to_t);
	// 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));

	function poly_load(o, b) {
	var v = o.field;
	if (b) {
	return v + 10;
	}
	return o;
	}

	var of1 = {a:0};
	of1.field = {};
	var of2 = {b:0};
	of2.field = 10;

	poly_load(of1, false);
	poly_load(of1, false);
	poly_load(of2, true);
	%OptimizeFunctionOnNextCall(poly_load);
	assertEquals("[object Object]10", poly_load(of1, true));

	// Ensure small object literals with doubles do not share double storage.
	function object_literal() { return {"a":1.5}; }
	var o8 = object_literal();
	var o9 = object_literal();
	o8.a = 4.6
	assertEquals(1.5, o9.a);

	// Ensure double storage is not leaked in the case of polymorphic loads.
	function load_poly(o) {
	return o.a;
	}

	var o10 = { "a": 1.6 };
	var o11 = { "b": 1, "a": 1.7 };
	load_poly(o10);
	load_poly(o10);
	load_poly(o11);
	%OptimizeFunctionOnNextCall(load_poly);
	var val = load_poly(o10);
	o10.a = 19.5;
	assertFalse(o10.a == val);

	// Ensure polymorphic loads only go monomorphic when the representations are
	// compatible.

	// Check polymorphic load from double + object fields.
	function load_mono(o) {
	return o.a1;
	}

	var object = {"x": 1};
	var o10 = { "a1": 1.6 };
	var o11 = { "a1": object, "b": 1 };
	load_mono(o10);
	load_mono(o10);
	load_mono(o11);
	%OptimizeFunctionOnNextCall(load_mono);
	assertEquals(object, load_mono(o11));

	// Check polymorphic load from smi + object fields.
	function load_mono2(o) {
	return o.a2;
	}

	var o12 = { "a2": 5 };
	var o13 = { "a2": object, "b": 1 };
	load_mono2(o12);
	load_mono2(o12);
	load_mono2(o13);
	%OptimizeFunctionOnNextCall(load_mono2);
	assertEquals(object, load_mono2(o13));

	// Check polymorphic load from double + double fields.
	function load_mono3(o) {
	return o.a3;
	}

	var o14 = { "a3": 1.6 };
	var o15 = { "a3": 1.8, "b": 1 };
	load_mono3(o14);
	load_mono3(o14);
	load_mono3(o15);
	%OptimizeFunctionOnNextCall(load_mono3);
	assertEquals(1.6, load_mono3(o14));
	assertEquals(1.8, load_mono3(o15));

	// Check that JSON parsing respects existing representations.
	var o16 = JSON.parse('{"a":1.5}');
	var o17 = JSON.parse('{"a":100}');
	assertTrue(%HaveSameMap(o16, o17));
	var o17_a = o17.a;
	assertEquals(100, o17_a);
	o17.a = 200;
	assertEquals(100, o17_a);
	assertEquals(200, o17.a);

	// Ensure normalizing results in ignored representations.
	var o18 = {};
	o18.field1 = 100;
	o18.field2 = 1;
	o18.to_delete = 100;

	var o19 = {};
	o19.field1 = 100;
	o19.field2 = 1.6;
	o19.to_delete = 100;

	assertFalse(%HaveSameMap(o18, o19));

	delete o18.to_delete;
	delete o19.to_delete;

	assertEquals(1, o18.field2);
	assertEquals(1.6, o19.field2);

	// Test megamorphic keyed stub behaviour in combination with representations.
	var some_object20 = {"a":1};
	var o20 = {};
	o20.smi = 1;
	o20.dbl = 1.5;
	o20.obj = some_object20;

	function keyed_load(o, k) {
	return o[k];
	}

	function keyed_store(o, k, v) {
	return o[k] = v;
	}

	var smi20 = keyed_load(o20, "smi");
	var dbl20 = keyed_load(o20, "dbl");
	var obj20 = keyed_load(o20, "obj");
	keyed_load(o20, "smi");
	keyed_load(o20, "dbl");
	keyed_load(o20, "obj");
	keyed_load(o20, "smi");
	keyed_load(o20, "dbl");
	keyed_load(o20, "obj");

	assertEquals(1, smi20);
	assertEquals(1.5, dbl20);
	assertEquals(some_object20, obj20);

	keyed_store(o20, "smi", 100);
	keyed_store(o20, "dbl", 100);
	keyed_store(o20, "obj", 100);
	keyed_store(o20, "smi", 100);
	keyed_store(o20, "dbl", 100);
	keyed_store(o20, "obj", 100);
	keyed_store(o20, "smi", 100);
	keyed_store(o20, "dbl", 100);
	keyed_store(o20, "obj", 100);

	assertEquals(1, smi20);
	assertEquals(1.5, dbl20);
	assertEquals(some_object20, obj20);

	assertEquals(100, o20.smi);
	assertEquals(100, o20.dbl);
	assertEquals(100, o20.dbl);

	function attr_mismatch_obj(v, writable) {
	var o = {};
	// Assign twice to make the field non-constant.
	// TODO(ishell): update test once constant field tracking is done.
	o.some_value = 0;
	o.some_value = v;
	Object.defineProperty(o, "second_value", {value:10, writable:writable});
	return o;
	}

	function is_writable(o, p) {
	return Object.getOwnPropertyDescriptor(o,p).writable;
	}

	var writable = attr_mismatch_obj(10, true);
	var non_writable1 = attr_mismatch_obj(10.5, false);
	assertTrue(is_writable(writable,"second_value"));
	assertFalse(is_writable(non_writable1,"second_value"));
	writable.some_value = 20.5;
	assertTrue(is_writable(writable,"second_value"));
	var non_writable2 = attr_mismatch_obj(10.5, false);
	assertTrue(%HaveSameMap(non_writable1, non_writable2));

	function test_f(v) {
	var o = {};
	o.vbf = v;
	o.func = test_f;
	return o;
	}

	function test_fic(o) {
	return o.vbf;
	}

	var ftest1 = test_f(10);
	var ftest2 = test_f(10);
	var ftest3 = test_f(10.5);
	var ftest4 = test_f(10);
	assertFalse(%HaveSameMap(ftest1, ftest3));
	assertTrue(%HaveSameMap(ftest3, ftest4));
	ftest2.func = is_writable;
	test_fic(ftest1);
	test_fic(ftest2);
	test_fic(ftest3);
	test_fic(ftest4);
	assertTrue(%HaveSameMap(ftest1, ftest3));
	assertTrue(%HaveSameMap(ftest3, ftest4));

	// Test representations and transition conversions.
	function read_first_double(o) {
	return o.first_double;
	}
	var df1 = {};
	df1.first_double=1.6;
	read_first_double(df1);
	read_first_double(df1);
	function some_function1() { return 10; }
	var df2 = {};
	df2.first_double = 1.7;
	df2.second_function = some_function1;
	function some_function2() { return 20; }
	var df3 = {};
	df3.first_double = 1.7;
	df3.second_function = some_function2;
	df1.first_double = 10;
	read_first_double(df1);

	// Test boilerplates with computed values.
	function none_boilerplate(a) {
	return {"a_none":a};
	}
	%OptimizeFunctionOnNextCall(none_boilerplate);
	var none_double1 = none_boilerplate(1.7);
	var none_double2 = none_boilerplate(1.9);
	assertTrue(%HaveSameMap(none_double1, none_double2));
	assertEquals(1.7, none_double1.a_none);
	assertEquals(1.9, none_double2.a_none);
	none_double2.a_none = 3.5;
	var none_double1 = none_boilerplate(1.7);
	var none_double2 = none_boilerplate(3.5);

	function none_to_smi(a) {
	return {"a_smi":a};
	}

	var none_smi1 = none_to_smi(1);
	var none_smi2 = none_to_smi(2);
	%OptimizeFunctionOnNextCall(none_to_smi);
	var none_smi3 = none_to_smi(3);
	assertTrue(%HaveSameMap(none_smi1, none_smi2));
	assertTrue(%HaveSameMap(none_smi1, none_smi3));
	assertEquals(1, none_smi1.a_smi);
	assertEquals(2, none_smi2.a_smi);
	assertEquals(3, none_smi3.a_smi);

	function none_to_double(a) {
	return {"a_double":a};
	}

	var none_to_double1 = none_to_double(1.5);
	var none_to_double2 = none_to_double(2.8);
	%OptimizeFunctionOnNextCall(none_to_double);
	var none_to_double3 = none_to_double(3.7);
	assertTrue(%HaveSameMap(none_to_double1, none_to_double2));
	assertTrue(%HaveSameMap(none_to_double1, none_to_double3));
	assertEquals(1.5, none_to_double1.a_double);
	assertEquals(2.8, none_to_double2.a_double);
	assertEquals(3.7, none_to_double3.a_double);

	function none_to_object(a) {
	return {"an_object":a};
	}

	var none_to_object1 = none_to_object(true);
	var none_to_object2 = none_to_object(false);
	%OptimizeFunctionOnNextCall(none_to_object);
	var none_to_object3 = none_to_object(3.7);
	assertTrue(%HaveSameMap(none_to_object1, none_to_object2));
	assertTrue(%HaveSameMap(none_to_object1, none_to_object3));
	assertEquals(true, none_to_object1.an_object);
	assertEquals(false, none_to_object2.an_object);
	assertEquals(3.7, none_to_object3.an_object);

	function double_to_object(a) {
	var o = {"d_to_h":1.8};
	o.d_to_h = a;
	return o;
	}

	var dh1 = double_to_object(true);
	var dh2 = double_to_object(false);
	assertTrue(%HaveSameMap(dh1, dh2));
	assertEquals(true, dh1.d_to_h);
	assertEquals(false, dh2.d_to_h);

	function smi_to_object(a) {
	var o = {"s_to_t":18};
	o.s_to_t = a;
	return o;
	}

	var st1 = smi_to_object(true);
	var st2 = smi_to_object(false);
	assertTrue(%HaveSameMap(st1, st2));
	assertEquals(true, st1.s_to_t);
	assertEquals(false, st2.s_to_t);