Files
swift-mirror/unittests/runtime/CompatibilityOverride.cpp
Mike Ash ecd6d4ddec Add a new ConcurrentReadableHashMap type. Switch the protocol conformance cache
to use it.

ConcurrentReadableHashMap is lock-free for readers, with writers using a lock to
ensure mutual exclusion amongst each other. The intent is to eventually replace
all uses ConcurrentMap with ConcurrentReadableHashMap.

ConcurrentReadableHashMap provides for relatively quick lookups by using a hash
table. Rearders perform an atomic increment/decrement in order to inform writers
that there are active readers. The design attempts to minimize wasted memory by
storing the actual elements out-of-line, and having the table store indices into
a separate array of elements.

The protocol conformance cache now uses ConcurrentReadableHashMap, which
provides faster lookups and less memory use than the previous ConcurrentMap
implementation. The previous implementation caches
ProtocolConformanceDescriptors and extracts the WitnessTable after the cache
lookup. The new implementation directly caches the WitnessTable, removing an
extra step (potentially a quite slow one) from the fast path.

The previous implementation used a generational scheme to detect when negative
cache entries became obsolete due to new dynamic libraries being loaded, and
update them in place. The new implementation just clears the entire cache when
libraries are loaded, greatly simplifying the code and saving the memory needed
to track the current generation in each negative cache entry. This means we need
to re-cache all requested conformances after loading a dynamic library, but
loading libraries at runtime is rare and slow anyway.

rdar://problem/67268325
2020-08-20 13:05:30 -04:00

201 lines
6.9 KiB
C++

//===--- CompatibilityOverride.cpp - Compatibility override tests ---------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
#if defined(__APPLE__) && defined(__MACH__)
#include "../../stdlib/public/runtime/CompatibilityOverride.h"
#include "swift/Runtime/Casting.h"
#include "swift/Runtime/Metadata.h"
#include "gtest/gtest.h"
#include <stdio.h>
using namespace swift;
bool EnableOverride;
bool Ran;
namespace {
template<typename T>
T getEmptyValue() {
return (T)0;
}
template<>
MetadataResponse getEmptyValue<MetadataResponse>() {
return MetadataResponse{nullptr, MetadataState::Complete};
}
template<>
TypeInfo getEmptyValue<TypeInfo>() {
return TypeInfo();
}
}
#define OVERRIDE(name, ret, attrs, ccAttrs, namespace, typedArgs, namedArgs) \
static ccAttrs ret name ## Override(COMPATIBILITY_UNPAREN typedArgs, \
Original_ ## name originalImpl) { \
if (!EnableOverride) \
return originalImpl namedArgs; \
Ran = true; \
return getEmptyValue<ret>(); \
}
#include "../../stdlib/public/runtime/CompatibilityOverride.def"
struct OverrideSection {
uintptr_t version;
#define OVERRIDE(name, ret, attrs, ccAttrs, namespace, typedArgs, namedArgs) \
Override_ ## name name;
#include "../../stdlib/public/runtime/CompatibilityOverride.def"
};
OverrideSection Overrides __attribute__((section("__DATA,__swift53_hooks"))) = {
0,
#define OVERRIDE(name, ret, attrs, ccAttrs, namespace, typedArgs, namedArgs) \
name ## Override,
#include "../../stdlib/public/runtime/CompatibilityOverride.def"
};
class CompatibilityOverrideTest : public ::testing::Test {
protected:
virtual void SetUp() {
// This check is a bit pointless, as long as you trust the section
// attribute to work correctly, but it ensures that the override
// section actually gets linked into the test executable. If it's not
// used then it disappears and the real tests begin to fail.
ASSERT_EQ(Overrides.version, static_cast<uintptr_t>(0));
EnableOverride = true;
Ran = false;
}
virtual void TearDown() {
EnableOverride = false;
ASSERT_TRUE(Ran);
}
};
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCast) {
auto Result = swift_dynamicCast(nullptr, nullptr, nullptr, nullptr,
DynamicCastFlags::Default);
ASSERT_FALSE(Result);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastClass) {
auto Result = swift_dynamicCastClass(nullptr, nullptr);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastClassUnconditional) {
auto Result = swift_dynamicCastClassUnconditional(nullptr, nullptr, nullptr, 0, 0);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastObjCClass) {
auto Result = swift_dynamicCastObjCClass(nullptr, nullptr);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastObjCClassUnconditional) {
auto Result = swift_dynamicCastObjCClassUnconditional(nullptr, nullptr, nullptr, 0, 0);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastForeignClass) {
auto Result = swift_dynamicCastForeignClass(nullptr, nullptr);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastForeignClassUnconditional) {
auto Result = swift_dynamicCastForeignClassUnconditional(nullptr, nullptr, nullptr, 0, 0);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastUnknownClass) {
auto Result = swift_dynamicCastUnknownClass(nullptr, nullptr);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastUnknownClassUnconditional) {
auto Result = swift_dynamicCastUnknownClassUnconditional(nullptr, nullptr, nullptr, 0, 0);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastMetatype) {
auto Result = swift_dynamicCastMetatype(nullptr, nullptr);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastMetatypeUnconditional) {
auto Result = swift_dynamicCastMetatypeUnconditional(nullptr, nullptr, nullptr, 0, 0);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastObjCClassMetatype) {
auto Result = swift_dynamicCastObjCClassMetatype(nullptr, nullptr);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastObjCClassMetatypeUnconditional) {
auto Result = swift_dynamicCastObjCClassMetatypeUnconditional(nullptr, nullptr, nullptr, 0, 0);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_dynamicCastForeignClassMetatype) {
auto Result = swift_dynamicCastForeignClassMetatype(nullptr, nullptr);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest,
test_swift_dynamicCastForeignClassMetatypeUnconditional) {
auto Result = swift_dynamicCastForeignClassMetatypeUnconditional(nullptr, nullptr, nullptr, 0, 0);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_conformsToProtocol) {
auto Result = swift_conformsToProtocol(nullptr, nullptr);
ASSERT_EQ(Result, nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_getTypeByMangledNode) {
Demangler demangler;
auto Result = swift_getTypeByMangledNode(MetadataState::Abstract,
demangler, nullptr, nullptr, nullptr,nullptr);
ASSERT_EQ(Result.getMetadata(), nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_getTypeByMangledName) {
auto Result = swift_getTypeByMangledName(MetadataState::Abstract,
"", nullptr, nullptr, nullptr);
ASSERT_EQ(Result.getMetadata(), nullptr);
}
TEST_F(CompatibilityOverrideTest, test_swift_getAssociatedTypeWitnessSlow) {
auto Result = swift_getAssociatedTypeWitnessSlow(MetadataState::Complete,
nullptr, nullptr,
nullptr, nullptr);
ASSERT_EQ(Result.Value, nullptr);
ASSERT_EQ(Result.State, MetadataState::Complete);
}
TEST_F(CompatibilityOverrideTest,
test_swift_getAssociatedConformanceWitnessSlow) {
auto Result = swift_getAssociatedConformanceWitnessSlow(
nullptr, nullptr, nullptr,
nullptr, nullptr);
ASSERT_EQ(Result, nullptr);
}
#endif