tests/RefCntTest.cpp - platform/external/skia - Gitiles

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */

 #include "include/core/SkRefCnt.h"
 #include "include/core/SkTypes.h"
 #include "include/private/SkWeakRefCnt.h"
 #include "tests/Test.h"

 #include <thread>

 static void bounce_ref(void* data) {
     SkRefCnt* ref = static_cast<SkRefCnt*>(data);
     for (int i = 0; i < 100000; ++i) {
         ref->ref();
         ref->unref();
     }
 }

 static void test_refCnt(skiatest::Reporter* reporter) {
     SkRefCnt* ref = new SkRefCnt();

     std::thread thing1(bounce_ref, ref);
     std::thread thing2(bounce_ref, ref);

     thing1.join();
     thing2.join();

     REPORTER_ASSERT(reporter, ref->unique());
     ref->unref();
 }

 static void bounce_weak_ref(void* data) {
     SkWeakRefCnt* ref = static_cast<SkWeakRefCnt*>(data);
     for (int i = 0; i < 100000; ++i) {
         if (ref->try_ref()) {
             ref->unref();
         }
     }
 }

 static void bounce_weak_weak_ref(void* data) {
     SkWeakRefCnt* ref = static_cast<SkWeakRefCnt*>(data);
     for (int i = 0; i < 100000; ++i) {
         ref->weak_ref();
         ref->weak_unref();
     }
 }

 static void test_weakRefCnt(skiatest::Reporter* reporter) {
     SkWeakRefCnt* ref = new SkWeakRefCnt();

     std::thread thing1(bounce_ref, ref);
     std::thread thing2(bounce_ref, ref);
     std::thread thing3(bounce_weak_ref, ref);
     std::thread thing4(bounce_weak_weak_ref, ref);

     thing1.join();
     thing2.join();
     thing3.join();
     thing4.join();

     REPORTER_ASSERT(reporter, ref->unique());
     SkDEBUGCODE(REPORTER_ASSERT(reporter, ref->getWeakCnt() == 1));
     ref->unref();
 }

 DEF_TEST(RefCnt, reporter) {
     test_refCnt(reporter);
     test_weakRefCnt(reporter);
 }

 ///////////////////////////////////////////////////////////////////////////////////////////////////

 static int gRefCounter;
 static int gUnrefCounter;
 static int gNewCounter;
 static int gDeleteCounter;

 #define check(reporter, ref, unref, make, kill)        \
     REPORTER_ASSERT(reporter, gRefCounter == ref);     \
     REPORTER_ASSERT(reporter, gUnrefCounter == unref); \
     REPORTER_ASSERT(reporter, gNewCounter == make);    \
     REPORTER_ASSERT(reporter, gDeleteCounter == kill)

 class Effect {
 public:
     Effect() : fRefCnt(1) {
         gNewCounter += 1;
     }
     virtual ~Effect() {}

     int fRefCnt;

     void ref() {
         gRefCounter += 1;
         fRefCnt += 1;
     }
     void unref() {
         gUnrefCounter += 1;

         SkASSERT(fRefCnt > 0);
         if (0 == --fRefCnt) {
             gDeleteCounter += 1;
             delete this;
         }
     }

     int* method() const { return new int; }
 };

 static sk_sp<Effect> Create() {
     return sk_make_sp<Effect>();
 }

 class Paint {
 public:
     sk_sp<Effect> fEffect;

     const sk_sp<Effect>& get() const { return fEffect; }

     void set(sk_sp<Effect> value) {
         fEffect = std::move(value);
     }
 };

 struct EffectImpl : public Effect {
     ~EffectImpl() override {}

     static sk_sp<EffectImpl> Create() {
         return sk_sp<EffectImpl>(new EffectImpl);
     }
     int fValue;
 };
 static sk_sp<Effect> make_effect() {
     auto foo = EffectImpl::Create();
     foo->fValue = 42;
     return std::move(foo);
 }

 static void reset_counters() {
     gRefCounter = 0;
     gUnrefCounter = 0;
     gNewCounter = 0;
     gDeleteCounter = 0;
 }
 DEF_TEST(sk_sp, reporter) {
     reset_counters();

     Paint paint;
     REPORTER_ASSERT(reporter, paint.fEffect.get() == nullptr);
     REPORTER_ASSERT(reporter, !paint.get());
     check(reporter, 0, 0, 0, 0);

     paint.set(Create());
     check(reporter, 0, 0, 1, 0);
     REPORTER_ASSERT(reporter, paint.fEffect.get()->fRefCnt == 1);

     if (paint.get()) {
         REPORTER_ASSERT(reporter, true);
     } else {
         REPORTER_ASSERT(reporter, false);
     }
     if (!paint.get()) {
         REPORTER_ASSERT(reporter, false);
     } else {
         REPORTER_ASSERT(reporter, true);
     }

     paint.set(nullptr);
     check(reporter, 0, 1, 1, 1);

     if (paint.get()) {
         REPORTER_ASSERT(reporter, false);
     } else {
         REPORTER_ASSERT(reporter, true);
     }
     if (!paint.get()) {
         REPORTER_ASSERT(reporter, true);
     } else {
         REPORTER_ASSERT(reporter, false);
     }

     auto e = Create();
     REPORTER_ASSERT(reporter, sizeof(e) == sizeof(void*));

     check(reporter, 0, 1, 2, 1);
     paint.set(e);
     check(reporter, 1, 1, 2, 1);
     REPORTER_ASSERT(reporter, paint.fEffect.get()->fRefCnt == 2);

     Paint paint2;
     paint2.set(paint.get());
     check(reporter, 2, 1, 2, 1);
     REPORTER_ASSERT(reporter, paint.fEffect.get()->fRefCnt == 3);

     // Test sk_sp::operator->
     delete paint.get()->method();
     check(reporter, 2, 1, 2, 1);

     // Test sk_sp::operator*
     delete (*paint.get()).method();
     check(reporter, 2, 1, 2, 1);

     paint.set(nullptr);
     e = nullptr;
     paint2.set(nullptr);
     check(reporter, 2, 4, 2, 2);

     reset_counters();
     {
         // Test convertible sk_sp assignment.
         check(reporter, 0, 0, 0, 0);
         sk_sp<Effect> foo(nullptr);
         REPORTER_ASSERT(reporter, !foo);
         foo = make_effect();
         REPORTER_ASSERT(reporter, foo);
         check(reporter, 0, 0, 1, 0);
     }
     check(reporter, 0, 1, 1, 1);

     // Test passing convertible rvalue into funtion.
     reset_counters();
     paint.set(EffectImpl::Create());
     check(reporter, 0, 0, 1, 0);
     paint.set(nullptr);
     check(reporter, 0, 1, 1, 1);

     reset_counters();
     auto baz = EffectImpl::Create();
     check(reporter, 0, 0, 1, 0);
     paint.set(std::move(baz));
     check(reporter, 0, 0, 1, 0);
     REPORTER_ASSERT(reporter, !baz);  // NOLINT(bugprone-use-after-move)
     paint.set(nullptr);
     check(reporter, 0, 1, 1, 1);

     reset_counters();
     {
         // test comparison operator with convertible type.
         sk_sp<EffectImpl> bar1 = EffectImpl::Create();
         sk_sp<Effect> bar2(bar1);  // convertible copy constructor
         check(reporter, 1, 0, 1, 0);
         REPORTER_ASSERT(reporter, bar1);
         REPORTER_ASSERT(reporter, bar2);
         REPORTER_ASSERT(reporter, bar1 == bar2);
         REPORTER_ASSERT(reporter, bar2 == bar1);
         REPORTER_ASSERT(reporter, !(bar1 != bar2));
         REPORTER_ASSERT(reporter, !(bar2 != bar1));
         sk_sp<Effect> bar3(nullptr);
         bar3 = bar1;  // convertible copy assignment
         check(reporter, 2, 0, 1, 0);

     }
     check(reporter, 2, 3, 1, 1);

     // test passing convertible copy into funtion.
     reset_counters();
     baz = EffectImpl::Create();
     check(reporter, 0, 0, 1, 0);
     paint.set(baz);
     check(reporter, 1, 0, 1, 0);
     baz = nullptr;
     check(reporter, 1, 1, 1, 0);
     paint.set(nullptr);
     check(reporter, 1, 2, 1, 1);

     {
         sk_sp<SkRefCnt> empty;
         sk_sp<SkRefCnt> notEmpty = sk_make_sp<SkRefCnt>();
         REPORTER_ASSERT(reporter, empty == sk_sp<SkRefCnt>());

         REPORTER_ASSERT(reporter, notEmpty != empty);
         REPORTER_ASSERT(reporter, empty != notEmpty);

         REPORTER_ASSERT(reporter, nullptr == empty);
         REPORTER_ASSERT(reporter, empty == nullptr);
         REPORTER_ASSERT(reporter, empty == empty);

         REPORTER_ASSERT(reporter, nullptr <= empty);
         REPORTER_ASSERT(reporter, empty <= nullptr);
         REPORTER_ASSERT(reporter, empty <= empty);

         REPORTER_ASSERT(reporter, nullptr >= empty);
         REPORTER_ASSERT(reporter, empty >= nullptr);
         REPORTER_ASSERT(reporter, empty >= empty);
     }

     {
         sk_sp<SkRefCnt> a = sk_make_sp<SkRefCnt>();
         sk_sp<SkRefCnt> b = sk_make_sp<SkRefCnt>();
         REPORTER_ASSERT(reporter, a != b);
         REPORTER_ASSERT(reporter, (a < b) != (b < a));
         REPORTER_ASSERT(reporter, (b > a) != (a > b));
         REPORTER_ASSERT(reporter, (a <= b) != (b <= a));
         REPORTER_ASSERT(reporter, (b >= a) != (a >= b));

         REPORTER_ASSERT(reporter, a == a);
         REPORTER_ASSERT(reporter, a <= a);
         REPORTER_ASSERT(reporter, a >= a);
     }

     // http://wg21.cmeerw.net/lwg/issue998
     {
         class foo : public SkRefCnt {
         public:
             foo() : bar(this) {}
             void reset() { bar.reset(); }
         private:
             sk_sp<foo> bar;
         };
         // The following should properly delete the object and not cause undefined behavior.
         // This is an ugly example, but the same issue can arise in more subtle ways.
         (new foo)->reset();
     }

     // https://crrev.com/0d4ef2583a6f19c3e61be04d36eb1a60b133832c
     {
         struct StructB;
         struct StructA : public SkRefCnt {
             sk_sp<StructB> b;
         };

         struct StructB : public SkRefCnt {
             sk_sp<StructA> a;
             ~StructB() override {} // Some clang versions don't emit this implicitly.
         };

         // Create a reference cycle.
         StructA* a = new StructA;
         a->b.reset(new StructB);
         a->b->a.reset(a);

         // Break the cycle by calling reset(). This will cause |a| (and hence, |a.b|)
         // to be deleted before the call to reset() returns. This tests that the
         // implementation of sk_sp::reset() doesn't access |this| after it
         // deletes the underlying pointer. This behaviour is consistent with the
         // definition of unique_ptr::reset in C++11.
         a->b.reset();
     }
 }

 namespace {
 struct FooAbstract : public SkRefCnt {
     virtual void f() = 0;
 };
 struct FooConcrete : public FooAbstract {
     void f() override {}
 };
 }
 static sk_sp<FooAbstract> make_foo() {
     // can not cast FooConcrete to FooAbstract.
     // can cast FooConcrete* to FooAbstract*.
     return sk_make_sp<FooConcrete>();
 }
 DEF_TEST(sk_make_sp, r) {
     auto x = make_foo();
 }

 // Test that reset() "adopts" ownership from the caller, even if we are given the same ptr twice
 //
 DEF_TEST(sk_sp_reset, r) {
     SkRefCnt* rc = new SkRefCnt;
     REPORTER_ASSERT(r, rc->unique());

     sk_sp<SkRefCnt> sp;
     sp.reset(rc);
     // We have transfered our ownership over to sp
     REPORTER_ASSERT(r, rc->unique());

     rc->ref();  // now "rc" is also an owner
     REPORTER_ASSERT(r, !rc->unique());

     sp.reset(rc);   // this should transfer our ownership over to sp
     REPORTER_ASSERT(r, rc->unique());
 }

 DEF_TEST(sk_sp_ref, r) {
     SkRefCnt* rc = new SkRefCnt;
     REPORTER_ASSERT(r, rc->unique());

     {
         sk_sp<SkRefCnt> sp = sk_ref_sp(rc);
         REPORTER_ASSERT(r, !rc->unique());
     }

     REPORTER_ASSERT(r, rc->unique());
     rc->unref();
 }
	/*
	* Copyright 2012 Google Inc.
	*
	* Use of this source code is governed by a BSD-style license that can be
	* found in the LICENSE file.
	*/

	#include "include/core/SkRefCnt.h"
	#include "include/core/SkTypes.h"
	#include "include/private/SkWeakRefCnt.h"
	#include "tests/Test.h"

	#include <thread>

	static void bounce_ref(void* data) {
	SkRefCnt* ref = static_cast<SkRefCnt*>(data);
	for (int i = 0; i < 100000; ++i) {
	ref->ref();
	ref->unref();
	}
	}

	static void test_refCnt(skiatest::Reporter* reporter) {
	SkRefCnt* ref = new SkRefCnt();

	std::thread thing1(bounce_ref, ref);
	std::thread thing2(bounce_ref, ref);

	thing1.join();
	thing2.join();

	REPORTER_ASSERT(reporter, ref->unique());
	ref->unref();
	}

	static void bounce_weak_ref(void* data) {
	SkWeakRefCnt* ref = static_cast<SkWeakRefCnt*>(data);
	for (int i = 0; i < 100000; ++i) {
	if (ref->try_ref()) {
	ref->unref();
	}
	}
	}

	static void bounce_weak_weak_ref(void* data) {
	SkWeakRefCnt* ref = static_cast<SkWeakRefCnt*>(data);
	for (int i = 0; i < 100000; ++i) {
	ref->weak_ref();
	ref->weak_unref();
	}
	}

	static void test_weakRefCnt(skiatest::Reporter* reporter) {
	SkWeakRefCnt* ref = new SkWeakRefCnt();

	std::thread thing1(bounce_ref, ref);
	std::thread thing2(bounce_ref, ref);
	std::thread thing3(bounce_weak_ref, ref);
	std::thread thing4(bounce_weak_weak_ref, ref);

	thing1.join();
	thing2.join();
	thing3.join();
	thing4.join();

	REPORTER_ASSERT(reporter, ref->unique());
	SkDEBUGCODE(REPORTER_ASSERT(reporter, ref->getWeakCnt() == 1));
	ref->unref();
	}

	DEF_TEST(RefCnt, reporter) {
	test_refCnt(reporter);
	test_weakRefCnt(reporter);
	}

	///////////////////////////////////////////////////////////////////////////////////////////////////

	static int gRefCounter;
	static int gUnrefCounter;
	static int gNewCounter;
	static int gDeleteCounter;

	#define check(reporter, ref, unref, make, kill) \
	REPORTER_ASSERT(reporter, gRefCounter == ref); \
	REPORTER_ASSERT(reporter, gUnrefCounter == unref); \
	REPORTER_ASSERT(reporter, gNewCounter == make); \
	REPORTER_ASSERT(reporter, gDeleteCounter == kill)

	class Effect {
	public:
	Effect() : fRefCnt(1) {
	gNewCounter += 1;
	}
	virtual ~Effect() {}

	int fRefCnt;

	void ref() {
	gRefCounter += 1;
	fRefCnt += 1;
	}
	void unref() {
	gUnrefCounter += 1;

	SkASSERT(fRefCnt > 0);
	if (0 == --fRefCnt) {
	gDeleteCounter += 1;
	delete this;
	}
	}

	int* method() const { return new int; }
	};

	static sk_sp<Effect> Create() {
	return sk_make_sp<Effect>();
	}

	class Paint {
	public:
	sk_sp<Effect> fEffect;

	const sk_sp<Effect>& get() const { return fEffect; }

	void set(sk_sp<Effect> value) {
	fEffect = std::move(value);
	}
	};

	struct EffectImpl : public Effect {
	~EffectImpl() override {}

	static sk_sp<EffectImpl> Create() {
	return sk_sp<EffectImpl>(new EffectImpl);
	}
	int fValue;
	};
	static sk_sp<Effect> make_effect() {
	auto foo = EffectImpl::Create();
	foo->fValue = 42;
	return std::move(foo);
	}

	static void reset_counters() {
	gRefCounter = 0;
	gUnrefCounter = 0;
	gNewCounter = 0;
	gDeleteCounter = 0;
	}
	DEF_TEST(sk_sp, reporter) {
	reset_counters();

	Paint paint;
	REPORTER_ASSERT(reporter, paint.fEffect.get() == nullptr);
	REPORTER_ASSERT(reporter, !paint.get());
	check(reporter, 0, 0, 0, 0);

	paint.set(Create());
	check(reporter, 0, 0, 1, 0);
	REPORTER_ASSERT(reporter, paint.fEffect.get()->fRefCnt == 1);

	if (paint.get()) {
	REPORTER_ASSERT(reporter, true);
	} else {
	REPORTER_ASSERT(reporter, false);
	}
	if (!paint.get()) {
	REPORTER_ASSERT(reporter, false);
	} else {
	REPORTER_ASSERT(reporter, true);
	}

	paint.set(nullptr);
	check(reporter, 0, 1, 1, 1);

	if (paint.get()) {
	REPORTER_ASSERT(reporter, false);
	} else {
	REPORTER_ASSERT(reporter, true);
	}
	if (!paint.get()) {
	REPORTER_ASSERT(reporter, true);
	} else {
	REPORTER_ASSERT(reporter, false);
	}

	auto e = Create();
	REPORTER_ASSERT(reporter, sizeof(e) == sizeof(void*));

	check(reporter, 0, 1, 2, 1);
	paint.set(e);
	check(reporter, 1, 1, 2, 1);
	REPORTER_ASSERT(reporter, paint.fEffect.get()->fRefCnt == 2);

	Paint paint2;
	paint2.set(paint.get());
	check(reporter, 2, 1, 2, 1);
	REPORTER_ASSERT(reporter, paint.fEffect.get()->fRefCnt == 3);

	// Test sk_sp::operator->
	delete paint.get()->method();
	check(reporter, 2, 1, 2, 1);

	// Test sk_sp::operator*
	delete (*paint.get()).method();
	check(reporter, 2, 1, 2, 1);

	paint.set(nullptr);
	e = nullptr;
	paint2.set(nullptr);
	check(reporter, 2, 4, 2, 2);

	reset_counters();
	{
	// Test convertible sk_sp assignment.
	check(reporter, 0, 0, 0, 0);
	sk_sp<Effect> foo(nullptr);
	REPORTER_ASSERT(reporter, !foo);
	foo = make_effect();
	REPORTER_ASSERT(reporter, foo);
	check(reporter, 0, 0, 1, 0);
	}
	check(reporter, 0, 1, 1, 1);

	// Test passing convertible rvalue into funtion.
	reset_counters();
	paint.set(EffectImpl::Create());
	check(reporter, 0, 0, 1, 0);
	paint.set(nullptr);
	check(reporter, 0, 1, 1, 1);

	reset_counters();
	auto baz = EffectImpl::Create();
	check(reporter, 0, 0, 1, 0);
	paint.set(std::move(baz));
	check(reporter, 0, 0, 1, 0);
	REPORTER_ASSERT(reporter, !baz); // NOLINT(bugprone-use-after-move)
	paint.set(nullptr);
	check(reporter, 0, 1, 1, 1);

	reset_counters();
	{
	// test comparison operator with convertible type.
	sk_sp<EffectImpl> bar1 = EffectImpl::Create();
	sk_sp<Effect> bar2(bar1); // convertible copy constructor
	check(reporter, 1, 0, 1, 0);
	REPORTER_ASSERT(reporter, bar1);
	REPORTER_ASSERT(reporter, bar2);
	REPORTER_ASSERT(reporter, bar1 == bar2);
	REPORTER_ASSERT(reporter, bar2 == bar1);
	REPORTER_ASSERT(reporter, !(bar1 != bar2));
	REPORTER_ASSERT(reporter, !(bar2 != bar1));
	sk_sp<Effect> bar3(nullptr);
	bar3 = bar1; // convertible copy assignment
	check(reporter, 2, 0, 1, 0);

	}
	check(reporter, 2, 3, 1, 1);

	// test passing convertible copy into funtion.
	reset_counters();
	baz = EffectImpl::Create();
	check(reporter, 0, 0, 1, 0);
	paint.set(baz);
	check(reporter, 1, 0, 1, 0);
	baz = nullptr;
	check(reporter, 1, 1, 1, 0);
	paint.set(nullptr);
	check(reporter, 1, 2, 1, 1);

	{
	sk_sp<SkRefCnt> empty;
	sk_sp<SkRefCnt> notEmpty = sk_make_sp<SkRefCnt>();
	REPORTER_ASSERT(reporter, empty == sk_sp<SkRefCnt>());

	REPORTER_ASSERT(reporter, notEmpty != empty);
	REPORTER_ASSERT(reporter, empty != notEmpty);

	REPORTER_ASSERT(reporter, nullptr == empty);
	REPORTER_ASSERT(reporter, empty == nullptr);
	REPORTER_ASSERT(reporter, empty == empty);

	REPORTER_ASSERT(reporter, nullptr <= empty);
	REPORTER_ASSERT(reporter, empty <= nullptr);
	REPORTER_ASSERT(reporter, empty <= empty);

	REPORTER_ASSERT(reporter, nullptr >= empty);
	REPORTER_ASSERT(reporter, empty >= nullptr);
	REPORTER_ASSERT(reporter, empty >= empty);
	}

	{
	sk_sp<SkRefCnt> a = sk_make_sp<SkRefCnt>();
	sk_sp<SkRefCnt> b = sk_make_sp<SkRefCnt>();
	REPORTER_ASSERT(reporter, a != b);
	REPORTER_ASSERT(reporter, (a < b) != (b < a));
	REPORTER_ASSERT(reporter, (b > a) != (a > b));
	REPORTER_ASSERT(reporter, (a <= b) != (b <= a));
	REPORTER_ASSERT(reporter, (b >= a) != (a >= b));

	REPORTER_ASSERT(reporter, a == a);
	REPORTER_ASSERT(reporter, a <= a);
	REPORTER_ASSERT(reporter, a >= a);
	}

	// http://wg21.cmeerw.net/lwg/issue998
	{
	class foo : public SkRefCnt {
	public:
	foo() : bar(this) {}
	void reset() { bar.reset(); }
	private:
	sk_sp<foo> bar;
	};
	// The following should properly delete the object and not cause undefined behavior.
	// This is an ugly example, but the same issue can arise in more subtle ways.
	(new foo)->reset();
	}

	// https://crrev.com/0d4ef2583a6f19c3e61be04d36eb1a60b133832c
	{
	struct StructB;
	struct StructA : public SkRefCnt {
	sk_sp<StructB> b;
	};

	struct StructB : public SkRefCnt {
	sk_sp<StructA> a;
	~StructB() override {} // Some clang versions don't emit this implicitly.
	};

	// Create a reference cycle.
	StructA* a = new StructA;
	a->b.reset(new StructB);
	a->b->a.reset(a);

	// Break the cycle by calling reset(). This will cause \|a\| (and hence, \|a.b\|)
	// to be deleted before the call to reset() returns. This tests that the
	// implementation of sk_sp::reset() doesn't access \|this\| after it
	// deletes the underlying pointer. This behaviour is consistent with the
	// definition of unique_ptr::reset in C++11.
	a->b.reset();
	}
	}

	namespace {
	struct FooAbstract : public SkRefCnt {
	virtual void f() = 0;
	};
	struct FooConcrete : public FooAbstract {
	void f() override {}
	};
	}
	static sk_sp<FooAbstract> make_foo() {
	// can not cast FooConcrete to FooAbstract.
	// can cast FooConcrete* to FooAbstract*.
	return sk_make_sp<FooConcrete>();
	}
	DEF_TEST(sk_make_sp, r) {
	auto x = make_foo();
	}

	// Test that reset() "adopts" ownership from the caller, even if we are given the same ptr twice
	//
	DEF_TEST(sk_sp_reset, r) {
	SkRefCnt* rc = new SkRefCnt;
	REPORTER_ASSERT(r, rc->unique());

	sk_sp<SkRefCnt> sp;
	sp.reset(rc);
	// We have transfered our ownership over to sp
	REPORTER_ASSERT(r, rc->unique());

	rc->ref(); // now "rc" is also an owner
	REPORTER_ASSERT(r, !rc->unique());

	sp.reset(rc); // this should transfer our ownership over to sp
	REPORTER_ASSERT(r, rc->unique());
	}

	DEF_TEST(sk_sp_ref, r) {
	SkRefCnt* rc = new SkRefCnt;
	REPORTER_ASSERT(r, rc->unique());

	{
	sk_sp<SkRefCnt> sp = sk_ref_sp(rc);
	REPORTER_ASSERT(r, !rc->unique());
	}

	REPORTER_ASSERT(r, rc->unique());
	rc->unref();
	}