Revert "Revert frozen RuntimeType objects and write barriers for frozen objects" (#76649)

This PR reverts #76235 with a few manual modifications:
The main issue why the initial PRs (#75573 and #76135) were reverted has just been resolved via #76251:

GC could collect some associated (with frozen objects) objects as unreachable, e.g. it could collect a SyncBlock, WeakReferences and Dependent handles associated with frozen objects which could (e.g. for a short period of time) be indeed unreachable but return back to life after.

Co-authored-by: Jan Kotas <[email protected]>
Co-authored-by: Jakob Botsch Nielsen <[email protected]>

Author: 3 people

src/coreclr/inc/CrstTypes.def

@@ -214,6 +214,11 @@ Crst FCall
 End
 
 Crst FrozenObjectHeap
+    Unordered
+End
+
+Crst MethodTableExposedObject
+    Unordered
 End
 
 Crst RetThunkCache

src/coreclr/inc/clrconfigvalues.h

@@ -399,11 +399,6 @@ CONFIG_DWORD_INFO(INTERNAL_LoaderHeapCallTracing, W("LoaderHeapCallTracing"), 0,
 RETAIL_CONFIG_DWORD_INFO(INTERNAL_CodeHeapReserveForJumpStubs, W("CodeHeapReserveForJumpStubs"), 1, "Percentage of code heap to reserve for jump stubs")
 RETAIL_CONFIG_DWORD_INFO(INTERNAL_BreakOnOutOfMemoryWithinRange, W("BreakOnOutOfMemoryWithinRange"), 0, "Break before out of memory within range exception is thrown")
 
-///
-/// Frozen segments (aka Frozen Object Heap)
-///
-RETAIL_CONFIG_DWORD_INFO(INTERNAL_UseFrozenObjectHeap, W("UseFrozenObjectHeap"), 1, "Use frozen object heap for certain types of objects (e.g. string literals) as an optimization.")
-
 ///
 /// Log
 ///

src/coreclr/inc/corinfo.h

@@ -2265,6 +2265,30 @@ class ICorStaticInfo
             int                         bufferSize  /* IN  */
             ) = 0;
 
+
+    //------------------------------------------------------------------------------
+    // printObjectDescription: Prints a (possibly truncated) textual UTF8 representation of the given
+    //    object to a preallocated buffer. It's intended to be used only for debug/diagnostic 
+    //    purposes such as JitDisasm. The buffer is null-terminated (even if truncated).
+    //
+    // Arguments:
+    //    handle     -          Direct object handle
+    //    buffer     -          Pointer to buffer
+    //    bufferSize -          Buffer size
+    //    pRequiredBufferSize - Full length of the textual UTF8 representation, can be used to call this
+    //                          API again with a bigger buffer to get the full string if the first buffer
+    //                          from that first attempt was not big enough.
+    //
+    // Return Value:
+    //    Bytes written to the given buffer, the range is [0..bufferSize)
+    //
+    virtual size_t printObjectDescription (
+            void*                       handle,                       /* IN  */
+            char*                       buffer,                       /* OUT */
+            size_t                      bufferSize,                   /* IN  */
+            size_t*                     pRequiredBufferSize = nullptr /* OUT */
+            ) = 0;
+
     /**********************************************************************************/
     //
     // ICorClassInfo
@@ -2475,6 +2499,10 @@ class ICorStaticInfo
             CORINFO_CLASS_HANDLE        cls
             ) = 0;
 
+    virtual void* getRuntimeTypePointer(
+            CORINFO_CLASS_HANDLE        cls
+            ) = 0;
+
     virtual bool getReadyToRunHelper(
             CORINFO_RESOLVED_TOKEN *        pResolvedToken,
             CORINFO_LOOKUP_KIND *           pGenericLookupKind,

src/coreclr/inc/crsttypes_generated.h

@@ -81,58 +81,59 @@ enum CrstType
     CrstLoaderHeap = 63,
     CrstManagedObjectWrapperMap = 64,
     CrstMethodDescBackpatchInfoTracker = 65,
-    CrstModule = 66,
-    CrstModuleFixup = 67,
-    CrstModuleLookupTable = 68,
-    CrstMulticoreJitHash = 69,
-    CrstMulticoreJitManager = 70,
-    CrstNativeImageEagerFixups = 71,
-    CrstNativeImageLoad = 72,
-    CrstNls = 73,
-    CrstNotifyGdb = 74,
-    CrstObjectList = 75,
-    CrstPEImage = 76,
-    CrstPendingTypeLoadEntry = 77,
-    CrstPgoData = 78,
-    CrstPinnedByrefValidation = 79,
-    CrstPinnedHeapHandleTable = 80,
-    CrstProfilerGCRefDataFreeList = 81,
-    CrstProfilingAPIStatus = 82,
-    CrstRCWCache = 83,
-    CrstRCWCleanupList = 84,
-    CrstReadyToRunEntryPointToMethodDescMap = 85,
-    CrstReflection = 86,
-    CrstReJITGlobalRequest = 87,
-    CrstRetThunkCache = 88,
-    CrstSavedExceptionInfo = 89,
-    CrstSaveModuleProfileData = 90,
-    CrstSecurityStackwalkCache = 91,
-    CrstSigConvert = 92,
-    CrstSingleUseLock = 93,
-    CrstSpecialStatics = 94,
-    CrstStackSampler = 95,
-    CrstStressLog = 96,
-    CrstStubCache = 97,
-    CrstStubDispatchCache = 98,
-    CrstStubUnwindInfoHeapSegments = 99,
-    CrstSyncBlockCache = 100,
-    CrstSyncHashLock = 101,
-    CrstSystemBaseDomain = 102,
-    CrstSystemDomain = 103,
-    CrstSystemDomainDelayedUnloadList = 104,
-    CrstThreadIdDispenser = 105,
-    CrstThreadStore = 106,
-    CrstTieredCompilation = 107,
-    CrstTypeEquivalenceMap = 108,
-    CrstTypeIDMap = 109,
-    CrstUMEntryThunkCache = 110,
-    CrstUMEntryThunkFreeListLock = 111,
-    CrstUniqueStack = 112,
-    CrstUnresolvedClassLock = 113,
-    CrstUnwindInfoTableLock = 114,
-    CrstVSDIndirectionCellLock = 115,
-    CrstWrapperTemplate = 116,
-    kNumberOfCrstTypes = 117
+    CrstMethodTableExposedObject = 66,
+    CrstModule = 67,
+    CrstModuleFixup = 68,
+    CrstModuleLookupTable = 69,
+    CrstMulticoreJitHash = 70,
+    CrstMulticoreJitManager = 71,
+    CrstNativeImageEagerFixups = 72,
+    CrstNativeImageLoad = 73,
+    CrstNls = 74,
+    CrstNotifyGdb = 75,
+    CrstObjectList = 76,
+    CrstPEImage = 77,
+    CrstPendingTypeLoadEntry = 78,
+    CrstPgoData = 79,
+    CrstPinnedByrefValidation = 80,
+    CrstPinnedHeapHandleTable = 81,
+    CrstProfilerGCRefDataFreeList = 82,
+    CrstProfilingAPIStatus = 83,
+    CrstRCWCache = 84,
+    CrstRCWCleanupList = 85,
+    CrstReadyToRunEntryPointToMethodDescMap = 86,
+    CrstReflection = 87,
+    CrstReJITGlobalRequest = 88,
+    CrstRetThunkCache = 89,
+    CrstSavedExceptionInfo = 90,
+    CrstSaveModuleProfileData = 91,
+    CrstSecurityStackwalkCache = 92,
+    CrstSigConvert = 93,
+    CrstSingleUseLock = 94,
+    CrstSpecialStatics = 95,
+    CrstStackSampler = 96,
+    CrstStressLog = 97,
+    CrstStubCache = 98,
+    CrstStubDispatchCache = 99,
+    CrstStubUnwindInfoHeapSegments = 100,
+    CrstSyncBlockCache = 101,
+    CrstSyncHashLock = 102,
+    CrstSystemBaseDomain = 103,
+    CrstSystemDomain = 104,
+    CrstSystemDomainDelayedUnloadList = 105,
+    CrstThreadIdDispenser = 106,
+    CrstThreadStore = 107,
+    CrstTieredCompilation = 108,
+    CrstTypeEquivalenceMap = 109,
+    CrstTypeIDMap = 110,
+    CrstUMEntryThunkCache = 111,
+    CrstUMEntryThunkFreeListLock = 112,
+    CrstUniqueStack = 113,
+    CrstUnresolvedClassLock = 114,
+    CrstUnwindInfoTableLock = 115,
+    CrstVSDIndirectionCellLock = 116,
+    CrstWrapperTemplate = 117,
+    kNumberOfCrstTypes = 118
 };
 
 #endif // __CRST_TYPES_INCLUDED
@@ -180,7 +181,7 @@ int g_rgCrstLevelMap[] =
     0,          // CrstExecuteManRangeLock
     0,          // CrstExternalObjectContextCache
     4,          // CrstFCall
-    0,          // CrstFrozenObjectHeap
+    -1,         // CrstFrozenObjectHeap
     7,          // CrstFuncPtrStubs
     10,         // CrstFusionAppCtx
     10,         // CrstGCCover
@@ -209,6 +210,7 @@ int g_rgCrstLevelMap[] =
     3,          // CrstLoaderHeap
     3,          // CrstManagedObjectWrapperMap
     10,         // CrstMethodDescBackpatchInfoTracker
+    -1,         // CrstMethodTableExposedObject
     5,          // CrstModule
     16,         // CrstModuleFixup
     4,          // CrstModuleLookupTable
@@ -331,6 +333,7 @@ LPCSTR g_rgCrstNameMap[] =
     "CrstLoaderHeap",
     "CrstManagedObjectWrapperMap",
     "CrstMethodDescBackpatchInfoTracker",
+    "CrstMethodTableExposedObject",
     "CrstModule",
     "CrstModuleFixup",
     "CrstModuleLookupTable",

src/coreclr/inc/icorjitinfoimpl_generated.h

@@ -175,6 +175,12 @@ int getStringLiteral(
           char16_t* buffer,
           int bufferSize) override;
 
+size_t printObjectDescription(
+          void* handle,
+          char* buffer,
+          size_t bufferSize,
+          size_t* pRequiredBufferSize) override;
+
 CorInfoType asCorInfoType(
           CORINFO_CLASS_HANDLE cls) override;
 
@@ -280,6 +286,9 @@ CorInfoHelpFunc getBoxHelper(
 CorInfoHelpFunc getUnBoxHelper(
           CORINFO_CLASS_HANDLE cls) override;
 
+void* getRuntimeTypePointer(
+          CORINFO_CLASS_HANDLE cls) override;
+
 bool getReadyToRunHelper(
           CORINFO_RESOLVED_TOKEN* pResolvedToken,
           CORINFO_LOOKUP_KIND* pGenericLookupKind,

src/coreclr/inc/jiteeversionguid.h

@@ -43,11 +43,11 @@ typedef const GUID *LPCGUID;
 #define GUID_DEFINED
 #endif // !GUID_DEFINED
 
-constexpr GUID JITEEVersionIdentifier = { /* eb8352bd-0a13-4b5b-badb-58f9ecc40c44 */
-    0xeb8352bd,
-    0x0a13,
-    0x4b5b,
-    {0xba, 0xdb, 0x58, 0xf9, 0xec, 0xc4, 0x0c, 0x44}
+constexpr GUID JITEEVersionIdentifier = { /* 3f5e4630-b29a-4aeb-bab7-07bdff43a156 */
+    0x3f5e4630,
+    0xb29a,
+    0x4aeb,
+    {0xba, 0xb7, 0x7, 0xbd, 0xff, 0x43, 0xa1, 0x56}
   };
 
 //////////////////////////////////////////////////////////////////////////////////////////////////////////

src/coreclr/jit/ICorJitInfo_API_names.h

@@ -41,6 +41,7 @@ DEF_CLR_API(getTokenTypeAsHandle)
 DEF_CLR_API(isValidToken)
 DEF_CLR_API(isValidStringRef)
 DEF_CLR_API(getStringLiteral)
+DEF_CLR_API(printObjectDescription)
 DEF_CLR_API(asCorInfoType)
 DEF_CLR_API(getClassName)
 DEF_CLR_API(getClassNameFromMetadata)
@@ -70,6 +71,7 @@ DEF_CLR_API(getSharedCCtorHelper)
 DEF_CLR_API(getTypeForBox)
 DEF_CLR_API(getBoxHelper)
 DEF_CLR_API(getUnBoxHelper)
+DEF_CLR_API(getRuntimeTypePointer)
 DEF_CLR_API(getReadyToRunHelper)
 DEF_CLR_API(getReadyToRunDelegateCtorHelper)
 DEF_CLR_API(getHelperName)

src/coreclr/jit/ICorJitInfo_API_wrapper.hpp

@@ -374,6 +374,18 @@ int WrapICorJitInfo::getStringLiteral(
     return temp;
 }
 
+size_t WrapICorJitInfo::printObjectDescription(
+          void* handle,
+          char* buffer,
+          size_t bufferSize,
+          size_t* pRequiredBufferSize)
+{
+    API_ENTER(printObjectDescription);
+    size_t temp = wrapHnd->printObjectDescription(handle, buffer, bufferSize, pRequiredBufferSize);
+    API_LEAVE(printObjectDescription);
+    return temp;
+}
+
 CorInfoType WrapICorJitInfo::asCorInfoType(
           CORINFO_CLASS_HANDLE cls)
 {
@@ -652,6 +664,15 @@ CorInfoHelpFunc WrapICorJitInfo::getUnBoxHelper(
     return temp;
 }
 
+void* WrapICorJitInfo::getRuntimeTypePointer(
+          CORINFO_CLASS_HANDLE cls)
+{
+    API_ENTER(getRuntimeTypePointer);
+    void* temp = wrapHnd->getRuntimeTypePointer(cls);
+    API_LEAVE(getRuntimeTypePointer);
+    return temp;
+}
+
 bool WrapICorJitInfo::getReadyToRunHelper(
           CORINFO_RESOLVED_TOKEN* pResolvedToken,
           CORINFO_LOOKUP_KIND* pGenericLookupKind,

src/coreclr/jit/assertionprop.cpp

@@ -2134,7 +2134,7 @@ void Compiler::optDebugCheckAssertion(AssertionDsc* assertion)
                     break;
                 case O1K_LCLVAR:
                     assert((lvaGetDesc(assertion->op1.lcl.lclNum)->lvType != TYP_REF) ||
-                           (assertion->op2.u1.iconVal == 0) || doesMethodHaveFrozenString());
+                           (assertion->op2.u1.iconVal == 0) || doesMethodHaveFrozenObjects());
                     break;
                 case O1K_VALUE_NUMBER:
                     assert((vnStore->TypeOfVN(assertion->op1.vn) != TYP_REF) || (assertion->op2.u1.iconVal == 0));
@@ -3408,7 +3408,7 @@ GenTree* Compiler::optConstantAssertionProp(AssertionDsc*        curAssertion,
 
                 // Make sure we don't retype const gc handles to TYP_I_IMPL
                 // Although, it's possible for e.g. GTF_ICON_STATIC_HDL
-                if (!newTree->IsIntegralConst(0) && newTree->IsIconHandle(GTF_ICON_STR_HDL))
+                if (!newTree->IsIntegralConst(0) && newTree->IsIconHandle(GTF_ICON_OBJ_HDL))
                 {
                     if (tree->TypeIs(TYP_BYREF))
                     {

src/coreclr/jit/compiler.cpp

@@ -9415,6 +9415,11 @@ void cTreeFlags(Compiler* comp, GenTree* tree)
                         chars += printf("[ICON_STR_HDL]");
                         break;
 
+                    case GTF_ICON_OBJ_HDL:
+
+                        chars += printf("[ICON_OBJ_HDL]");
+                        break;
+
                     case GTF_ICON_CONST_PTR:
 
                         chars += printf("[ICON_CONST_PTR]");