Revert "Feature: dynamic expansion for generic dictionaries (#26262)"

This reverts commit d840c75.

Author: stephentoub

Documentation/botr/shared-generics.md

@@ -6984,15 +6984,15 @@ NativeImageDumper::DumpMethodTable( PTR_MethodTable mt, const char * name,
         if( currentDictionary != NULL )
         {
             PTR_DictionaryEntry entry(currentDictionary->EntryAddr(0));
-            
+
             PTR_DictionaryLayout layout( clazz->GetDictionaryLayout() );
 
             DisplayStartStructure( "Dictionary",
                                    DPtrToPreferredAddr(currentDictionary),
                                    //if there is a layout, use it to compute
                                    //the size, otherwise there is just the one
                                    //entry.
-                                   DictionaryLayout::GetDictionarySizeFromLayout(mt->GetNumGenericArgs(), layout),
+                                   DictionaryLayout::GetFirstDictionaryBucketSize(mt->GetNumGenericArgs(), layout),
                                    METHODTABLES );
 
             DisplayStartArrayWithOffset( m_pEntries, NULL, Dictionary,
@@ -8018,7 +8018,7 @@ void NativeImageDumper::DumpMethodDesc( PTR_MethodDesc md, PTR_Module module )
             {
                 PTR_DictionaryLayout layout(wrapped->IsSharedByGenericMethodInstantiations()
                                             ? dac_cast<TADDR>(wrapped->GetDictLayoutRaw()) : NULL );
-                dictSize = DictionaryLayout::GetDictionarySizeFromLayout(imd->GetNumGenericMethodArgs(), 
+                dictSize = DictionaryLayout::GetFirstDictionaryBucketSize(imd->GetNumGenericMethodArgs(),
                                                                           layout);
             }
         }

src/debug/daccess/nidump.cpp

@@ -2068,10 +2068,6 @@ void SystemDomain::LoadBaseSystemClasses()
     g_pDelegateClass = MscorlibBinder::GetClass(CLASS__DELEGATE);
     g_pMulticastDelegateClass = MscorlibBinder::GetClass(CLASS__MULTICAST_DELEGATE);
 
-#ifndef CROSSGEN_COMPILE
-    CrossLoaderAllocatorHashSetup::EnsureTypesLoaded();
-#endif
-
     // used by IsImplicitInterfaceOfSZArray
     MscorlibBinder::GetClass(CLASS__IENUMERABLEGENERIC);
     MscorlibBinder::GetClass(CLASS__ICOLLECTIONGENERIC);
@@ -2087,6 +2083,10 @@ void SystemDomain::LoadBaseSystemClasses()
     g_pUtf8StringClass = MscorlibBinder::GetClass(CLASS__UTF8_STRING);
 #endif // FEATURE_UTF8STRING
 
+#ifndef CROSSGEN_COMPILE
+    CrossLoaderAllocatorHashSetup::EnsureTypesLoaded();
+#endif
+
 #ifndef CROSSGEN_COMPILE
     ECall::PopulateManagedStringConstructors();
 #endif // CROSSGEN_COMPILE

src/vm/appdomain.cpp

@@ -556,7 +556,6 @@ void Module::Initialize(AllocMemTracker *pamTracker, LPCWSTR szName)
     m_FixupCrst.Init(CrstModuleFixup, (CrstFlags)(CRST_HOST_BREAKABLE|CRST_REENTRANCY));
     m_InstMethodHashTableCrst.Init(CrstInstMethodHashTable, CRST_REENTRANCY);
     m_ISymUnmanagedReaderCrst.Init(CrstISymUnmanagedReader, CRST_DEBUGGER_THREAD);
-    m_DictionaryCrst.Init(CrstDomainLocalBlock);
 
     if (!m_file->HasNativeImage())
     {
@@ -688,12 +687,8 @@ void Module::Initialize(AllocMemTracker *pamTracker, LPCWSTR szName)
     }
 #endif // defined (PROFILING_SUPPORTED) &&!defined(DACCESS_COMPILE) && !defined(CROSSGEN_COMPILE)
 
-#ifndef CROSSGEN_COMPILE
-    m_dynamicSlotsHashForTypes.Init(GetLoaderAllocator());
-    m_dynamicSlotsHashForMethods.Init(GetLoaderAllocator());
-#endif
-
     LOG((LF_CLASSLOADER, LL_INFO10, "Loaded pModule: \"%ws\".\n", GetDebugName()));
+
 }
 
 #endif // DACCESS_COMPILE
@@ -13238,327 +13233,6 @@ void ReflectionModule::ReleaseILData()
 
     Module::ReleaseILData();
 }
-
-TypeHandle* AllocateNewMethodDictionaryForExpansion(InstantiatedMethodDesc* pIMD, DWORD cbSize)
-{
-    TypeHandle* pInstOrPerInstInfo = (TypeHandle*)(void*)pIMD->GetLoaderAllocator()->GetHighFrequencyHeap()->AllocMem(S_SIZE_T(cbSize + sizeof(void*)));
-    ZeroMemory(pInstOrPerInstInfo, cbSize + sizeof(void*));
-
-    // Slot[-1] points at previous dictionary to help with diagnostics when investigating crashes
-    *(byte**)pInstOrPerInstInfo = (byte*)pIMD->m_pPerInstInfo.GetValue() + 1;
-    pInstOrPerInstInfo++;
-
-    // Copy old dictionary entry contents
-    memcpy(pInstOrPerInstInfo, (const void*)pIMD->m_pPerInstInfo.GetValue(), pIMD->GetDictionarySlotsSize());
-
-    ULONG_PTR* pSizeSlot = ((ULONG_PTR*)pInstOrPerInstInfo) + pIMD->GetNumGenericMethodArgs();
-    *pSizeSlot = cbSize;
-
-    return pInstOrPerInstInfo;
-}
-
-TypeHandle* AllocateNewTypeDictionaryForExpansion(MethodTable* pMT, DWORD cbSize)
-{
-    TypeHandle* pInstOrPerInstInfo = (TypeHandle*)(void*)pMT->GetLoaderAllocator()->GetHighFrequencyHeap()->AllocMem(S_SIZE_T(cbSize + sizeof(void*)));
-    ZeroMemory(pInstOrPerInstInfo, cbSize + sizeof(void*));
-
-    // Slot[-1] points at previous dictionary to help with diagnostics when investigating crashes
-    *(byte**)pInstOrPerInstInfo = (byte*)pMT->GetPerInstInfo()[pMT->GetNumDicts() - 1].GetValue() + 1;
-    pInstOrPerInstInfo++;
-
-    // Copy old dictionary entry contents
-    memcpy(pInstOrPerInstInfo, (const void*)pMT->GetPerInstInfo()[pMT->GetNumDicts() - 1].GetValue(), pMT->GetDictionarySlotsSize());
-
-    ULONG_PTR* pSizeSlot = ((ULONG_PTR*)pInstOrPerInstInfo) + pMT->GetNumGenericArgs();
-    *pSizeSlot = cbSize;
-
-    return pInstOrPerInstInfo;
-}
-
-#ifdef _DEBUG
-void Module::EnsureTypeRecorded(MethodTable* pMT)
-{
-    _ASSERTE(SystemDomain::SystemModule()->m_DictionaryCrst.OwnedByCurrentThread());
-
-    BOOL typeExistsInHashtable = FALSE;
-    auto lamda = [&typeExistsInHashtable, pMT](OBJECTREF obj, MethodTable* pMTKey, MethodTable* pMTValue)
-    {
-        typeExistsInHashtable = (pMT == pMTValue);
-        return pMT != pMTValue;
-    };
-
-    m_dynamicSlotsHashForTypes.VisitValuesOfKey(pMT->GetCanonicalMethodTable(), lamda);
-    _ASSERTE(typeExistsInHashtable);
-}
-
-void Module::EnsureMethodRecorded(MethodDesc* pMD)
-{
-    _ASSERTE(SystemDomain::SystemModule()->m_DictionaryCrst.OwnedByCurrentThread());
-
-    BOOL methodExistsInHashtable = FALSE;
-    auto lamda = [&methodExistsInHashtable, pMD](OBJECTREF obj, MethodDesc* pMDKey, MethodDesc* pMDValue)
-    {
-        methodExistsInHashtable = (pMD== pMDValue);
-        return pMD != pMDValue;
-    };
-
-    m_dynamicSlotsHashForMethods.VisitValuesOfKey(pMD->GetExistingWrappedMethodDesc(), lamda);
-    _ASSERTE(methodExistsInHashtable);
-}
-#endif
-
-void Module::RecordTypeForDictionaryExpansion_Locked(MethodTable* pGenericParentMT, MethodTable* pDependencyMT)
-{
-    CONTRACTL
-    {
-        GC_TRIGGERS;
-        PRECONDITION(CheckPointer(pGenericParentMT) && CheckPointer(pDependencyMT));
-        PRECONDITION(pGenericParentMT->HasInstantiation() && pGenericParentMT != pGenericParentMT->GetCanonicalMethodTable());
-        PRECONDITION(SystemDomain::SystemModule()->m_DictionaryCrst.OwnedByCurrentThread());
-    }
-    CONTRACTL_END
-
-    DictionaryLayout* pDictLayout = pDependencyMT->GetClass()->GetDictionaryLayout();
-    if (pDictLayout != NULL && pDictLayout->GetMaxSlots() > 0)
-    {
-        DWORD sizeFromDictLayout = DictionaryLayout::GetDictionarySizeFromLayout(pDependencyMT->GetNumGenericArgs(), pDictLayout);
-        if (pDependencyMT->GetDictionarySlotsSize() != sizeFromDictLayout)
-        {
-            _ASSERT(pDependencyMT->GetDictionarySlotsSize() < sizeFromDictLayout);
-
-            //
-            // Another thread got a chance to expand the dictionary layout and expand the dictionary slots of
-            // other types, but not for this one yet because we're still in the process of recording it for 
-            // expansions.
-            // Expand the dictionary slots here before finally adding the type to the hashtable.
-            //
-
-            TypeHandle* pInstOrPerInstInfo = AllocateNewTypeDictionaryForExpansion(pDependencyMT, sizeFromDictLayout);
-
-            // Publish the new dictionary slots to the type.
-            TypeHandle** pPerInstInfo = (TypeHandle**)pDependencyMT->GetPerInstInfo()->GetValuePtr();
-            FastInterlockExchangePointer(pPerInstInfo + (pDependencyMT->GetNumDicts() - 1), pInstOrPerInstInfo);
-
-            FlushProcessWriteBuffers();
-        }
-    }
-
-    GCX_COOP();
-    m_dynamicSlotsHashForTypes.Add(pGenericParentMT->GetCanonicalMethodTable(), pDependencyMT, GetLoaderAllocator());
-}
-
-void Module::RecordMethodForDictionaryExpansion_Locked(MethodDesc* pDependencyMD)
-{
-    CONTRACTL
-    {
-        GC_TRIGGERS;
-        PRECONDITION(CheckPointer(pDependencyMD) && pDependencyMD->HasMethodInstantiation() && pDependencyMD->IsInstantiatingStub());
-        PRECONDITION(pDependencyMD->GetDictionaryLayout() != NULL && pDependencyMD->GetDictionaryLayout()->GetMaxSlots() > 0);
-        PRECONDITION(SystemDomain::SystemModule()->m_DictionaryCrst.OwnedByCurrentThread());
-    }
-    CONTRACTL_END
-
-    DictionaryLayout* pDictLayout = pDependencyMD->GetDictionaryLayout();
-    InstantiatedMethodDesc* pIMDDependency = pDependencyMD->AsInstantiatedMethodDesc();
-
-    DWORD sizeFromDictLayout = DictionaryLayout::GetDictionarySizeFromLayout(pDependencyMD->GetNumGenericMethodArgs(), pDictLayout);
-    if (pIMDDependency->GetDictionarySlotsSize() != sizeFromDictLayout)
-    {
-        _ASSERT(pIMDDependency->GetDictionarySlotsSize() < sizeFromDictLayout);
-
-        //
-        // Another thread got a chance to expand the dictionary layout and expand the dictionary slots of
-        // other methods, but not for this one yet because we're still in the process of recording it for 
-        // expansions.
-        // Expand the dictionary slots here before finally adding the method to the hashtable.
-        //
-
-        TypeHandle* pInstOrPerInstInfo = AllocateNewMethodDictionaryForExpansion(pIMDDependency, sizeFromDictLayout);
-
-        FastInterlockExchangePointer((TypeHandle**)pIMDDependency->m_pPerInstInfo.GetValuePtr(), pInstOrPerInstInfo);
-
-        FlushProcessWriteBuffers();
-    }
-
-    GCX_COOP();
-
-    _ASSERTE(pDependencyMD->GetExistingWrappedMethodDesc() != NULL);
-    m_dynamicSlotsHashForMethods.Add(pDependencyMD->GetExistingWrappedMethodDesc(), pDependencyMD, GetLoaderAllocator());
-}
-
-void Module::ExpandTypeDictionaries_Locked(MethodTable* pMT, DictionaryLayout* pOldLayout, DictionaryLayout* pNewLayout)
-{
-    CONTRACTL
-    {
-        STANDARD_VM_CHECK;
-        INJECT_FAULT(ThrowOutOfMemory(););
-        PRECONDITION(CheckPointer(pOldLayout) && CheckPointer(pNewLayout));
-        PRECONDITION(CheckPointer(pMT) && pMT->HasInstantiation() && pMT->GetClass()->GetDictionaryLayout() == pOldLayout);
-        PRECONDITION(SystemDomain::SystemModule()->m_DictionaryCrst.OwnedByCurrentThread());
-    }
-    CONTRACTL_END
-
-    GCX_COOP();
-
-    MethodTable* pCanonMT = pMT->GetCanonicalMethodTable();
-    DWORD oldInfoSize = DictionaryLayout::GetDictionarySizeFromLayout(pMT->GetNumGenericArgs(), pOldLayout);
-    DWORD newInfoSize = DictionaryLayout::GetDictionarySizeFromLayout(pMT->GetNumGenericArgs(), pNewLayout);
-
-    //
-    // Dictionary expansion for types needs to be done in multiple steps, given how derived types do not directly embed dictionaries
-    // from parent types, but instead reference them from directly from the parent types. Also, this is necessary to ensure correctness
-    // for lock-free read operations for dictionary slots:
-    //      1) Allocate new dictionaries for all instantiated types of the same typedef as the one being expanded.
-    //      2) After all allocations and initializations are completed, publish the dictionaries to the types in #1 after 
-    //         flushing write buffers
-    //      3) For all types that derive from #1, update the embedded dictinoary pointer to the newly allocated one.
-    //
-
-    struct NewDictionary
-    {
-        MethodTable* pMT;
-        TypeHandle* pDictSlots;
-    };
-    StackSArray<NewDictionary> dictionaryUpdates;
-
-#ifdef _DEBUG
-    auto expandPerInstInfos = [oldInfoSize, newInfoSize, &dictionaryUpdates](OBJECTREF obj, MethodTable* pMTKey, MethodTable* pMTToUpdate)
-#else
-    auto expandPerInstInfos = [newInfoSize, &dictionaryUpdates](OBJECTREF obj, MethodTable* pMTKey, MethodTable* pMTToUpdate)
-#endif
-    {
-        if (!pMTToUpdate->HasSameTypeDefAs(pMTKey))
-            return true;
-
-        _ASSERTE(pMTToUpdate != pMTToUpdate->GetCanonicalMethodTable() && pMTToUpdate->GetCanonicalMethodTable() == pMTKey);
-        _ASSERTE(pMTToUpdate->GetDictionarySlotsSize() == oldInfoSize);
-
-        TypeHandle* pInstOrPerInstInfo = AllocateNewTypeDictionaryForExpansion(pMTToUpdate, newInfoSize);
-
-        NewDictionary entry;
-        entry.pMT = pMTToUpdate;
-        entry.pDictSlots = pInstOrPerInstInfo;
-        dictionaryUpdates.Append(entry);
-
-        return true; // Keep walking
-    };
-
-    m_dynamicSlotsHashForTypes.VisitValuesOfKey(pCanonMT, expandPerInstInfos);
-
-    // Flush write buffers to ensure new dictionaries are fully writted and initalized before publishing them
-    FlushProcessWriteBuffers();
-
-    for (SArray<NewDictionary>::Iterator i = dictionaryUpdates.Begin(); i != dictionaryUpdates.End(); i++)
-    {
-        MethodTable* pMT = i->pMT;
-        TypeHandle** pPerInstInfo = (TypeHandle**)pMT->GetPerInstInfo()->GetValuePtr();
-        FastInterlockExchangePointer(pPerInstInfo + (pMT->GetNumDicts() - 1), i->pDictSlots);
-        _ASSERTE(pMT->GetDictionarySlotsSize() == newInfoSize);
-        _ASSERTE((TypeHandle*)pMT->GetPerInstInfo()[pMT->GetNumDicts() - 1].GetValue() == i->pDictSlots);
-    }
-
-    auto updateDependentDicts = [](OBJECTREF obj, MethodTable* pMTKey, MethodTable* pMTToUpdate)
-    {
-        if (pMTToUpdate->HasSameTypeDefAs(pMTKey))
-            return true;
-
-        MethodTable* pCurrentMT = pMTToUpdate->GetParentMethodTable();
-        while (pCurrentMT)
-        {
-            if (pCurrentMT->HasSameTypeDefAs(pMTKey))
-            {
-                DWORD dictToUpdate = pCurrentMT->GetNumDicts() - 1;
-                Dictionary* pUpdatedParentDict = pCurrentMT->GetPerInstInfo()[dictToUpdate].GetValue();
-                TypeHandle** pPerInstInfo = (TypeHandle**)pMTToUpdate->GetPerInstInfo()->GetValuePtr();
-                FastInterlockExchangePointer(pPerInstInfo + dictToUpdate, (TypeHandle*)pUpdatedParentDict);
-                _ASSERTE(pMTToUpdate->GetPerInstInfo()[dictToUpdate].GetValue() == pUpdatedParentDict);
-
-                return true; // Keep walking
-            }
-            pCurrentMT = pCurrentMT->GetParentMethodTable();
-        }
-
-        UNREACHABLE();
-    };
-
-    m_dynamicSlotsHashForTypes.VisitValuesOfKey(pCanonMT, updateDependentDicts);
-
-    // Ensure no other thread uses old dictionary pointers
-    FlushProcessWriteBuffers();
-}
-
-void Module::ExpandMethodDictionaries_Locked(MethodDesc* pMD, DictionaryLayout* pOldLayout, DictionaryLayout* pNewLayout)
-{
-    CONTRACTL
-    {
-        STANDARD_VM_CHECK;
-        INJECT_FAULT(ThrowOutOfMemory(););
-        PRECONDITION(CheckPointer(pOldLayout) && CheckPointer(pNewLayout));
-        PRECONDITION(CheckPointer(pMD));
-        PRECONDITION(pMD->HasMethodInstantiation() && pMD->GetDictionaryLayout() == pOldLayout);
-        PRECONDITION(SystemDomain::SystemModule()->m_DictionaryCrst.OwnedByCurrentThread());
-    }
-    CONTRACTL_END
-
-    GCX_COOP();
-
-    //
-    // Dictionary expansion for methods needs to be done in two steps to ensure correctness for lock-free read operations 
-    // for dictionary slots:
-    //      1) Allocate new dictionaries for all instantiated methods sharing the same canonical form as the input method
-    //      2) After all allocations and initializations are completed, publish the dictionaries to the methods after 
-    //         flushing write buffers
-    //
-
-    MethodDesc* pCanonMD = pMD->IsInstantiatingStub() ? pMD->GetExistingWrappedMethodDesc() : pMD;
-    _ASSERTE(pCanonMD != NULL);
-    DWORD oldInfoSize = DictionaryLayout::GetDictionarySizeFromLayout(pMD->GetNumGenericMethodArgs(), pOldLayout);
-    DWORD newInfoSize = DictionaryLayout::GetDictionarySizeFromLayout(pMD->GetNumGenericMethodArgs(), pNewLayout);
-
-    struct NewDictionary
-    {
-        InstantiatedMethodDesc* pIMD;
-        TypeHandle* pDictSlots;
-    };
-    StackSArray<NewDictionary> dictionaryUpdates;
-
-#ifdef _DEBUG
-    auto lambda = [oldInfoSize, newInfoSize, &dictionaryUpdates](OBJECTREF obj, MethodDesc* pMDKey, MethodDesc* pMDToUpdate)
-#else
-    auto lambda = [newInfoSize, &dictionaryUpdates](OBJECTREF obj, MethodDesc* pMDKey, MethodDesc* pMDToUpdate)
-#endif
-    {
-        // Update m_pPerInstInfo for the pMethodDesc being visited here
-        _ASSERTE(pMDToUpdate->IsInstantiatingStub() && pMDToUpdate->GetExistingWrappedMethodDesc() == pMDKey);
-
-        InstantiatedMethodDesc* pInstantiatedMD = pMDToUpdate->AsInstantiatedMethodDesc();
-        _ASSERTE(pInstantiatedMD->GetDictionarySlotsSize() == oldInfoSize);
-
-        TypeHandle* pInstOrPerInstInfo = AllocateNewMethodDictionaryForExpansion(pInstantiatedMD, newInfoSize);
-
-        NewDictionary entry;
-        entry.pIMD = pInstantiatedMD;
-        entry.pDictSlots = pInstOrPerInstInfo;
-        dictionaryUpdates.Append(entry);
-
-        return true; // Keep walking
-    };
-
-    m_dynamicSlotsHashForMethods.VisitValuesOfKey(pCanonMD, lambda);
-
-    // Flush write buffers to ensure new dictionaries are fully writted and initalized before publishing them
-    FlushProcessWriteBuffers();
-
-    for (SArray<NewDictionary>::Iterator i = dictionaryUpdates.Begin(); i != dictionaryUpdates.End(); i++)
-    {
-        FastInterlockExchangePointer((TypeHandle**)i->pIMD->m_pPerInstInfo.GetValuePtr(), i->pDictSlots);
-        _ASSERTE((TypeHandle*)i->pIMD->m_pPerInstInfo.GetValue() == i->pDictSlots);
-        _ASSERTE(i->pIMD->GetDictionarySlotsSize() == newInfoSize);
-    }
-
-    // Ensure no other thread uses old dictionary pointers
-    FlushProcessWriteBuffers();
-}
 #endif // !CROSSGEN_COMPILE
 
 #endif // !DACCESS_COMPILE