Revert "Inject IJW Copy Constructor calls in the JIT instead of in th…

…e IL stubs (dotnet#106000)"

This reverts commit ec067c8.

Just being cautions -- the PR was merged before all tests had run.

src/coreclr/System.Private.CoreLib/src/System/Runtime/CompilerServices/RuntimeHelpers.CoreCLR.cs

@@ -344,12 +344,6 @@ internal static int EnumCompareTo<T>(T x, T y) where T : struct, Enum
             return x.CompareTo(y);
         }
 
-
-        // The body of this function will be created by the EE for the specific type.
-        // See getILIntrinsicImplementation for how this happens.
-        [Intrinsic]
-        internal static extern unsafe void CopyConstruct<T>(T* dest, T* src) where T : unmanaged;
-
         internal static ref byte GetRawData(this object obj) =>
             ref Unsafe.As<RawData>(obj).Data;
 

src/coreclr/System.Private.CoreLib/src/System/StubHelpers.cs

@@ -1315,6 +1315,75 @@ public IntPtr AddRef()
         }
     }  // class CleanupWorkListElement
 
+    internal unsafe struct CopyConstructorCookie
+    {
+        private void* m_source;
+
+        private nuint m_destinationOffset;
+
+        public delegate*<void*, void*, void> m_copyConstructor;
+
+        public delegate*<void*, void> m_destructor;
+
+        public CopyConstructorCookie* m_next;
+
+        [StackTraceHidden]
+        public void ExecuteCopy(void* destinationBase)
+        {
+            if (m_copyConstructor != null)
+            {
+                m_copyConstructor((byte*)destinationBase + m_destinationOffset, m_source);
+            }
+
+            if (m_destructor != null)
+            {
+                m_destructor(m_source);
+            }
+        }
+    }
+
+    internal unsafe struct CopyConstructorChain
+    {
+        public void* m_realTarget;
+        public CopyConstructorCookie* m_head;
+
+        public void Add(CopyConstructorCookie* cookie)
+        {
+            cookie->m_next = m_head;
+            m_head = cookie;
+        }
+
+        [ThreadStatic]
+        private static CopyConstructorChain s_copyConstructorChain;
+
+        public void Install(void* realTarget)
+        {
+            m_realTarget = realTarget;
+            s_copyConstructorChain = this;
+        }
+
+        [StackTraceHidden]
+        private void ExecuteCopies(void* destinationBase)
+        {
+            for (CopyConstructorCookie* current = m_head; current != null; current = current->m_next)
+            {
+                current->ExecuteCopy(destinationBase);
+            }
+        }
+
+        [UnmanagedCallersOnly]
+        [StackTraceHidden]
+        public static void* ExecuteCurrentCopiesAndGetTarget(void* destinationBase)
+        {
+            void* target = s_copyConstructorChain.m_realTarget;
+            s_copyConstructorChain.ExecuteCopies(destinationBase);
+            // Reset this instance to ensure we don't accidentally execute the copies again.
+            // All of the pointers point to the stack, so we don't need to free any memory.
+            s_copyConstructorChain = default;
+            return target;
+        }
+    }
+
     internal static partial class StubHelpers
     {
         [MethodImpl(MethodImplOptions.InternalCall)]

src/coreclr/inc/corinfo.h

@@ -644,7 +644,6 @@ enum CorInfoTypeWithMod
 {
     CORINFO_TYPE_MASK            = 0x3F,        // lower 6 bits are type mask
     CORINFO_TYPE_MOD_PINNED      = 0x40,        // can be applied to CLASS, or BYREF to indicate pinned
-    CORINFO_TYPE_MOD_COPY_WITH_HELPER = 0x80    // can be applied to VALUECLASS to indicate 'needs helper to copy'
 };
 
 inline CorInfoType strip(CorInfoTypeWithMod val) {
@@ -3326,8 +3325,6 @@ class ICorDynamicInfo : public ICorStaticInfo
     // but for tailcalls, the contract is that JIT leaves the indirection cell in
     // a register during tailcall.
     virtual void updateEntryPointForTailCall(CORINFO_CONST_LOOKUP* entryPoint) = 0;
-
-    virtual CORINFO_METHOD_HANDLE getSpecialCopyHelper(CORINFO_CLASS_HANDLE type) = 0;
 };
 
 /**********************************************************************************/

src/coreclr/inc/icorjitinfoimpl_generated.h

@@ -742,9 +742,6 @@ uint32_t getJitFlags(
           CORJIT_FLAGS* flags,
           uint32_t sizeInBytes) override;
 
-CORINFO_METHOD_HANDLE getSpecialCopyHelper(
-          CORINFO_CLASS_HANDLE type) override;
-
 /**********************************************************************************/
 // clang-format on
 /**********************************************************************************/

src/coreclr/inc/jiteeversionguid.h

@@ -43,11 +43,11 @@ typedef const GUID *LPCGUID;
 #define GUID_DEFINED
 #endif // !GUID_DEFINED
 
-constexpr GUID JITEEVersionIdentifier = { /* 62865a69-7c84-4ba5-8636-a7dec55c05a7 */
-    0x62865a69,
-    0x7c84,
-    0x4ba5,
-    {0x86, 0x36, 0xa7, 0xde, 0xc5, 0x5c, 0x05, 0xa7}
+constexpr GUID JITEEVersionIdentifier = { /* f43f9022-8795-4791-ba55-c450d76cfeb9 */
+    0xf43f9022,
+    0x8795,
+    0x4791,
+    {0xba, 0x55, 0xc4, 0x50, 0xd7, 0x6c, 0xfe, 0xb9}
   };
 
 //////////////////////////////////////////////////////////////////////////////////////////////////////////

src/coreclr/jit/ICorJitInfo_names_generated.h

@@ -180,6 +180,5 @@ DEF_CLR_API(recordRelocation)
 DEF_CLR_API(getRelocTypeHint)
 DEF_CLR_API(getExpectedTargetArchitecture)
 DEF_CLR_API(getJitFlags)
-DEF_CLR_API(getSpecialCopyHelper)
 
 #undef DEF_CLR_API

src/coreclr/jit/ICorJitInfo_wrapper_generated.hpp

@@ -1742,15 +1742,6 @@ uint32_t WrapICorJitInfo::getJitFlags(
     return temp;
 }
 
-CORINFO_METHOD_HANDLE WrapICorJitInfo::getSpecialCopyHelper(
-          CORINFO_CLASS_HANDLE type)
-{
-    API_ENTER(getSpecialCopyHelper);
-    CORINFO_METHOD_HANDLE temp = wrapHnd->getSpecialCopyHelper(type);
-    API_LEAVE(getSpecialCopyHelper);
-    return temp;
-}
-
 /**********************************************************************************/
 // clang-format on
 /**********************************************************************************/

src/coreclr/jit/compiler.cpp

@@ -1989,10 +1989,6 @@ void Compiler::compInit(ArenaAllocator*       pAlloc,
     m_fpStructLoweringCache = nullptr;
 #endif
 
-#if defined(TARGET_X86) && defined(FEATURE_IJW)
-    m_specialCopyArgs = nullptr;
-#endif
-
     // check that HelperCallProperties are initialized
 
     assert(s_helperCallProperties.IsPure(CORINFO_HELP_GET_GCSTATIC_BASE));

src/coreclr/jit/compiler.h

@@ -5703,36 +5703,6 @@ class Compiler
     const CORINFO_SWIFT_LOWERING* GetSwiftLowering(CORINFO_CLASS_HANDLE clsHnd);
 #endif
 
-#if defined(TARGET_X86) && defined(FEATURE_IJW)
-    bool* m_specialCopyArgs;
-    bool recordArgRequiresSpecialCopy(unsigned argNum)
-    {
-        if (argNum >= info.compArgsCount)
-        {
-            return false;
-        }
-
-        if (m_specialCopyArgs == nullptr)
-        {
-            m_specialCopyArgs = new (getAllocator()) bool[info.compArgsCount];
-            memset(m_specialCopyArgs, 0, info.compArgsCount * sizeof(bool));
-        }
-
-        m_specialCopyArgs[argNum] = true;
-        return true;
-    }
-
-    bool argRequiresSpecialCopy(unsigned argNum)
-    {
-        return argNum < info.compArgsCount && m_specialCopyArgs != nullptr && m_specialCopyArgs[argNum];
-    }
-
-    bool compHasSpecialCopyArgs()
-    {
-        return m_specialCopyArgs != nullptr;
-    }
-#endif
-
     void optRecordLoopMemoryDependence(GenTree* tree, BasicBlock* block, ValueNum memoryVN);
     void optCopyLoopMemoryDependence(GenTree* fromTree, GenTree* toTree);
 

src/coreclr/jit/gentree.cpp

@@ -16599,7 +16599,6 @@ GenTree* Compiler::gtNewTempStore(
         valTyp      = lvaGetRealType(val->AsLclVar()->GetLclNum());
         val->gtType = valTyp;
     }
-
     var_types dstTyp = varDsc->TypeGet();
 
     /* If the variable's lvType is not yet set then set it here */

src/coreclr/jit/gschecks.cpp

@@ -516,59 +516,13 @@ void Compiler::gsParamsToShadows()
             continue;
         }
 
-#if defined(TARGET_X86) && defined(FEATURE_IJW)
-        if (lclNum < info.compArgsCount && argRequiresSpecialCopy(lclNum) && (varDsc->TypeGet() == TYP_STRUCT))
-        {
-            JITDUMP("arg%02u requires special copy, using special copy helper to copy to shadow var V%02u\n", lclNum,
-                    shadowVarNum);
-            CORINFO_METHOD_HANDLE copyHelper =
-                info.compCompHnd->getSpecialCopyHelper(varDsc->GetLayout()->GetClassHandle());
-            GenTreeCall* call = gtNewCallNode(CT_USER_FUNC, copyHelper, TYP_VOID);
-
-            GenTree* src = gtNewLclVarAddrNode(lclNum);
-            GenTree* dst = gtNewLclVarAddrNode(shadowVarNum);
-
-            call->gtArgs.PushBack(this, NewCallArg::Primitive(dst));
-            call->gtArgs.PushBack(this, NewCallArg::Primitive(src));
-
-            fgEnsureFirstBBisScratch();
-            compCurBB = fgFirstBB; // Needed by some morphing
-            if (opts.IsReversePInvoke())
-            {
-                JITDUMP(
-                    "Inserting special copy helper call at the end of the first block after Reverse P/Invoke transition\n");
-
-#ifdef DEBUG
-                // assert that we don't have any uses of the local variable in the first block
-                // before we insert the shadow copy statement.
-                for (Statement* const stmt : fgFirstBB->Statements())
-                {
-                    assert(!gtHasRef(stmt->GetRootNode(), lclNum));
-                }
-#endif
-                // If we are in a reverse P/Invoke, then we need to insert
-                // the call at the end of the first block as we need to do the GC transition
-                // before we can call the helper.
-                (void)fgNewStmtAtEnd(fgFirstBB, fgMorphTree(call));
-            }
-            else
-            {
-                JITDUMP("Inserting special copy helper call at the beginning of the first block\n");
-                (void)fgNewStmtAtBeg(fgFirstBB, fgMorphTree(call));
-            }
-        }
-        else
-#endif // TARGET_X86 && FEATURE_IJW
-        {
-            GenTree* src = gtNewLclvNode(lclNum, varDsc->TypeGet());
-            src->gtFlags |= GTF_DONT_CSE;
+        GenTree* src = gtNewLclvNode(lclNum, varDsc->TypeGet());
+        src->gtFlags |= GTF_DONT_CSE;
+        GenTree* store = gtNewStoreLclVarNode(shadowVarNum, src);
 
-            GenTree* store = gtNewStoreLclVarNode(shadowVarNum, src);
-
-            fgEnsureFirstBBisScratch();
-            compCurBB = fgFirstBB; // Needed by some morphing
-            (void)fgNewStmtAtBeg(fgFirstBB, fgMorphTree(store));
-        }
+        fgEnsureFirstBBisScratch();
+        compCurBB = fgFirstBB; // Needed by some morphing
+        (void)fgNewStmtAtBeg(fgFirstBB, fgMorphTree(store));
     }
     compCurBB = nullptr;
 

src/coreclr/jit/lclvars.cpp

@@ -653,19 +653,6 @@ void Compiler::lvaInitUserArgs(InitVarDscInfo* varDscInfo, unsigned skipArgs, un
         CorInfoTypeWithMod corInfoType = info.compCompHnd->getArgType(&info.compMethodInfo->args, argLst, &typeHnd);
         varDsc->lvIsParam              = 1;
 
-#if defined(TARGET_X86) && defined(FEATURE_IJW)
-        if ((corInfoType & CORINFO_TYPE_MOD_COPY_WITH_HELPER) != 0)
-        {
-            CorInfoType typeWithoutMod = strip(corInfoType);
-            if (typeWithoutMod == CORINFO_TYPE_VALUECLASS || typeWithoutMod == CORINFO_TYPE_PTR ||
-                typeWithoutMod == CORINFO_TYPE_BYREF)
-            {
-                JITDUMP("Marking user arg%02u as requiring special copy semantics\n", i);
-                recordArgRequiresSpecialCopy(i);
-            }
-        }
-#endif // TARGET_X86 && FEATURE_IJW
-
         lvaInitVarDsc(varDsc, varDscInfo->varNum, strip(corInfoType), typeHnd, argLst, &info.compMethodInfo->args);
 
         if (strip(corInfoType) == CORINFO_TYPE_CLASS)