Move memset/memcpy helpers to managed impl

docs/design/coreclr/botr/guide-for-porting.md

@@ -413,12 +413,6 @@ Here is an annotated list of the stubs implemented for Unix on Arm64.
         Today use of this feature on Unix requires hand-written IL. On Windows
         this feature is commonly used by C++/CLI
 
-3.  EH Correctness. Some helpers are written in assembly to provide well known
-    locations for NullReferenceExceptions to be generated out of a SIGSEGV
-    signal.
-
-    1.  `JIT_MemSet`, and `JIT_MemCpy` have this requirement
-
 #### cgencpu.h
 
 This header is included by various code in the VM directory. It provides a large

src/coreclr/System.Private.CoreLib/src/System/Array.CoreCLR.cs

@@ -74,7 +74,7 @@ private static unsafe void CopyImpl(Array sourceArray, int sourceIndex, Array de
                 if (pMT->ContainsGCPointers)
                     Buffer.BulkMoveWithWriteBarrier(ref dst, ref src, byteCount);
                 else
-                    Buffer.Memmove(ref dst, ref src, byteCount);
+                    SpanHelpers.Memmove(ref dst, ref src, byteCount);
 
                 // GC.KeepAlive(sourceArray) not required. pMT kept alive via sourceArray
                 return;
@@ -184,7 +184,7 @@ private static unsafe void CopyImplUnBoxEachElement(Array sourceArray, int sourc
                 }
                 else
                 {
-                    Buffer.Memmove(ref dest, ref obj.GetRawData(), destSize);
+                    SpanHelpers.Memmove(ref dest, ref obj.GetRawData(), destSize);
                 }
             }
         }

src/coreclr/System.Private.CoreLib/src/System/Object.CoreCLR.cs

@@ -30,7 +30,7 @@ protected internal unsafe object MemberwiseClone()
             if (RuntimeHelpers.GetMethodTable(clone)->ContainsGCPointers)
                 Buffer.BulkMoveWithWriteBarrier(ref dst, ref src, byteCount);
             else
-                Buffer.Memmove(ref dst, ref src, byteCount);
+                SpanHelpers.Memmove(ref dst, ref src, byteCount);
 
             return clone;
         }

src/coreclr/System.Private.CoreLib/src/System/Runtime/InteropServices/Marshal.CoreCLR.cs

@@ -266,7 +266,7 @@ public static unsafe void StructureToPtr(object structure, IntPtr ptr, bool fDel
             }
             else
             {
-                Buffer.Memmove(ref *(byte*)ptr, ref structure.GetRawData(), size);
+                SpanHelpers.Memmove(ref *(byte*)ptr, ref structure.GetRawData(), size);
             }
         }
 
@@ -291,7 +291,7 @@ private static unsafe void PtrToStructureHelper(IntPtr ptr, object structure, bo
             }
             else
             {
-                Buffer.Memmove(ref structure.GetRawData(), ref *(byte*)ptr, size);
+                SpanHelpers.Memmove(ref structure.GetRawData(), ref *(byte*)ptr, size);
             }
         }
 

src/coreclr/System.Private.CoreLib/src/System/String.CoreCLR.cs

@@ -39,7 +39,7 @@ internal static unsafe void InternalCopy(string src, IntPtr dest, int len)
         {
             if (len != 0)
             {
-                Buffer.Memmove(ref *(byte*)dest, ref Unsafe.As<char, byte>(ref src.GetRawStringData()), (nuint)len);
+                SpanHelpers.Memmove(ref *(byte*)dest, ref Unsafe.As<char, byte>(ref src.GetRawStringData()), (nuint)len);
             }
         }
 

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

@@ -103,7 +103,7 @@ internal static unsafe IntPtr ConvertToNative(int flags, string strManaged, IntP
                     // + 1 for the null character from the user.  + 1 for the null character we put in.
                     pbNativeBuffer = (byte*)Marshal.AllocCoTaskMem(nb + 2);
 
-                    Buffer.Memmove(ref *pbNativeBuffer, ref MemoryMarshal.GetArrayDataReference(bytes), (nuint)nb);
+                    SpanHelpers.Memmove(ref *pbNativeBuffer, ref MemoryMarshal.GetArrayDataReference(bytes), (nuint)nb);
                 }
             }
 
@@ -360,7 +360,7 @@ internal static unsafe IntPtr ConvertToNative(string strManaged, bool fBestFit,
 
                 Debug.Assert(nbytesused >= 0 && nbytesused < nbytes, "Insufficient buffer allocated in VBByValStrMarshaler.ConvertToNative");
 
-                Buffer.Memmove(ref *pNative, ref MemoryMarshal.GetArrayDataReference(bytes), (nuint)nbytesused);
+                SpanHelpers.Memmove(ref *pNative, ref MemoryMarshal.GetArrayDataReference(bytes), (nuint)nbytesused);
 
                 pNative[nbytesused] = 0;
                 *pLength = nbytesused;
@@ -409,7 +409,7 @@ internal static unsafe IntPtr ConvertToNative(int flags, string strManaged)
             IntPtr bstr = Marshal.AllocBSTRByteLen(length);
             if (bytes != null)
             {
-                Buffer.Memmove(ref *(byte*)bstr, ref MemoryMarshal.GetArrayDataReference(bytes), length);
+                SpanHelpers.Memmove(ref *(byte*)bstr, ref MemoryMarshal.GetArrayDataReference(bytes), length);
             }
 
             return bstr;
@@ -1484,7 +1484,7 @@ internal static unsafe void FmtClassUpdateNativeInternal(object obj, byte* pNati
             }
             else
             {
-                Buffer.Memmove(ref *pNative, ref obj.GetRawData(), size);
+                SpanHelpers.Memmove(ref *pNative, ref obj.GetRawData(), size);
             }
         }
 
@@ -1503,7 +1503,7 @@ internal static unsafe void FmtClassUpdateCLRInternal(object obj, byte* pNative)
             }
             else
             {
-                Buffer.Memmove(ref obj.GetRawData(), ref *pNative, size);
+                SpanHelpers.Memmove(ref obj.GetRawData(), ref *pNative, size);
             }
         }
 

src/coreclr/inc/corinfo.h

@@ -572,7 +572,10 @@ enum CorInfoHelpFunc
     CORINFO_HELP_INIT_PINVOKE_FRAME,   // initialize an inlined PInvoke Frame for the JIT-compiler
 
     CORINFO_HELP_MEMSET,                // Init block of memory
+    CORINFO_HELP_MEMZERO,               // Init block of memory with zeroes
     CORINFO_HELP_MEMCPY,                // Copy block of memory
+    CORINFO_HELP_NATIVE_MEMSET,         // Init block of memory using native memset (not safe for pDst being null, 
+                                        // not safe for unbounded size, does not trigger GC)
 
     CORINFO_HELP_RUNTIMEHANDLE_METHOD,          // determine a type/field/method handle at run-time
     CORINFO_HELP_RUNTIMEHANDLE_METHOD_LOG,      // determine a type/field/method handle at run-time, with IBC logging

src/coreclr/inc/jiteeversionguid.h

@@ -43,11 +43,11 @@ typedef const GUID *LPCGUID;
 #define GUID_DEFINED
 #endif // !GUID_DEFINED
 
-constexpr GUID JITEEVersionIdentifier = { /* 1f30d12b-38f1-4f1e-a08a-831def882aa4 */
-    0x1f30d12b,
-    0x38f1,
-    0x4f1e,
-    {0xa0, 0x8a, 0x83, 0x1d, 0xef, 0x88, 0x2a, 0xa4}
+constexpr GUID JITEEVersionIdentifier = { /* 86eab154-5d93-4fad-bc07-e94fd9268b70 */
+    0x86eab154,
+    0x5d93,
+    0x4fad,
+    {0xbc, 0x07, 0xe9, 0x4f, 0xd9, 0x26, 0x8b, 0x70}
   };
 
 //////////////////////////////////////////////////////////////////////////////////////////////////////////

src/coreclr/inc/jithelpers.h

@@ -235,13 +235,10 @@
     DYNAMICJITHELPER(CORINFO_HELP_INIT_PINVOKE_FRAME,  NULL,        CORINFO_HELP_SIG_REG_ONLY)
 #endif
 
-#ifdef TARGET_X86
-    JITHELPER(CORINFO_HELP_MEMSET,              NULL,               CORINFO_HELP_SIG_CANNOT_USE_ALIGN_STUB)
-    JITHELPER(CORINFO_HELP_MEMCPY,              NULL,               CORINFO_HELP_SIG_CANNOT_USE_ALIGN_STUB)
-#else
-    JITHELPER(CORINFO_HELP_MEMSET,              JIT_MemSet,         CORINFO_HELP_SIG_REG_ONLY)
-    JITHELPER(CORINFO_HELP_MEMCPY,              JIT_MemCpy,         CORINFO_HELP_SIG_REG_ONLY)
-#endif
+    DYNAMICJITHELPER(CORINFO_HELP_MEMSET, NULL, CORINFO_HELP_SIG_REG_ONLY)
+    DYNAMICJITHELPER(CORINFO_HELP_MEMZERO, NULL, CORINFO_HELP_SIG_REG_ONLY)
+    DYNAMICJITHELPER(CORINFO_HELP_MEMCPY, NULL, CORINFO_HELP_SIG_REG_ONLY)
+    JITHELPER(CORINFO_HELP_NATIVE_MEMSET, Jit_NativeMemSet, CORINFO_HELP_SIG_REG_ONLY)
 
     // Generics
     JITHELPER(CORINFO_HELP_RUNTIMEHANDLE_METHOD,    JIT_GenericHandleMethod,        CORINFO_HELP_SIG_REG_ONLY)

src/coreclr/inc/readytorun.h

@@ -20,7 +20,7 @@
 // If you update this, ensure you run `git grep MINIMUM_READYTORUN_MAJOR_VERSION`
 // and handle pending work.
 #define READYTORUN_MAJOR_VERSION 0x0009
-#define READYTORUN_MINOR_VERSION 0x0001
+#define READYTORUN_MINOR_VERSION 0x0002
 
 #define MINIMUM_READYTORUN_MAJOR_VERSION 0x009
 
@@ -33,6 +33,8 @@
 // R2R Version 8.0 Changes the alignment of the Int128 type
 // R2R Version 9.0 adds support for the Vector512 type
 // R2R Version 9.1 adds new helpers to allocate objects on frozen segments
+// R2R Version 9.2 adds MemZero and NativeMemSet helpers
+
 
 struct READYTORUN_CORE_HEADER
 {
@@ -325,7 +327,9 @@ enum ReadyToRunHelper
     READYTORUN_HELPER_Stelem_Ref                = 0x38,
     READYTORUN_HELPER_Ldelema_Ref               = 0x39,
 
-    READYTORUN_HELPER_MemSet                    = 0x40,
+    READYTORUN_HELPER_MemZero                   = 0x3E,
+    READYTORUN_HELPER_MemSet                    = 0x3F,
+    READYTORUN_HELPER_NativeMemSet              = 0x40,
     READYTORUN_HELPER_MemCpy                    = 0x41,
 
     // PInvoke helpers
@@ -441,10 +445,6 @@ enum ReadyToRunHelper
     READYTORUN_HELPER_StackProbe                = 0x111,
 
     READYTORUN_HELPER_GetCurrentManagedThreadId = 0x112,
-
-    // Array helpers for use with native ints
-    READYTORUN_HELPER_Stelem_Ref_I                = 0x113,
-    READYTORUN_HELPER_Ldelema_Ref_I               = 0x114,
 };
 
 #include "readytoruninstructionset.h"

src/coreclr/inc/readytorunhelpers.h

@@ -29,6 +29,8 @@ HELPER(READYTORUN_HELPER_Stelem_Ref,                CORINFO_HELP_ARRADDR_ST,
 HELPER(READYTORUN_HELPER_Ldelema_Ref,               CORINFO_HELP_LDELEMA_REF,                       )
 
 HELPER(READYTORUN_HELPER_MemSet,                    CORINFO_HELP_MEMSET,                            )
+HELPER(READYTORUN_HELPER_MemZero,                   CORINFO_HELP_MEMZERO,                           )
+HELPER(READYTORUN_HELPER_NativeMemSet,              CORINFO_HELP_NATIVE_MEMSET,                     )
 HELPER(READYTORUN_HELPER_MemCpy,                    CORINFO_HELP_MEMCPY,                            )
 
 HELPER(READYTORUN_HELPER_LogMethodEnter,            CORINFO_HELP_BBT_FCN_ENTER,                     )

src/coreclr/jit/codegencommon.cpp

@@ -8403,7 +8403,9 @@ void CodeGen::genPoisonFrame(regMaskTP regLiveIn)
             GetEmitter()->emitIns_R_S(INS_lea, EA_PTRSIZE, REG_ARG_0, (int)varNum, 0);
             instGen_Set_Reg_To_Imm(EA_4BYTE, REG_ARG_1, static_cast<char>(poisonVal));
             instGen_Set_Reg_To_Imm(EA_PTRSIZE, REG_ARG_2, size);
-            genEmitHelperCall(CORINFO_HELP_MEMSET, 0, EA_UNKNOWN);
+
+            // Call non-managed memset
+            genEmitHelperCall(CORINFO_HELP_NATIVE_MEMSET, 0, EA_UNKNOWN);
             // May kill REG_SCRATCH, so we need to reload it.
             hasPoisonImm = false;
 #endif

src/coreclr/jit/fgbasic.cpp

@@ -1332,7 +1332,7 @@ void Compiler::fgFindJumpTargets(const BYTE* codeAddr, IL_OFFSET codeSize, Fixed
                             case NI_System_SpanHelpers_ClearWithoutReferences:
                             case NI_System_SpanHelpers_Fill:
                             case NI_System_SpanHelpers_SequenceEqual:
-                            case NI_System_Buffer_Memmove:
+                            case NI_System_SpanHelpers_Memmove:
                             {
                                 if (FgStack::IsConstArgument(pushedStack.Top(), impInlineInfo))
                                 {

src/coreclr/jit/fgprofile.cpp

@@ -1947,7 +1947,7 @@ class ValueHistogramProbeVisitor final : public GenTreeVisitor<ValueHistogramPro
         if (node->IsCall() && node->AsCall()->IsSpecialIntrinsic())
         {
             const NamedIntrinsic ni = m_compiler->lookupNamedIntrinsic(node->AsCall()->gtCallMethHnd);
-            if ((ni == NI_System_Buffer_Memmove) || (ni == NI_System_SpanHelpers_SequenceEqual))
+            if ((ni == NI_System_SpanHelpers_Memmove) || (ni == NI_System_SpanHelpers_SequenceEqual))
             {
                 m_functor(m_compiler, node);
             }
@@ -2274,7 +2274,7 @@ class ValueHistogramProbeInserter
             return;
         }
 
-        assert(node->AsCall()->IsSpecialIntrinsic(compiler, NI_System_Buffer_Memmove) ||
+        assert(node->AsCall()->IsSpecialIntrinsic(compiler, NI_System_SpanHelpers_Memmove) ||
                node->AsCall()->IsSpecialIntrinsic(compiler, NI_System_SpanHelpers_SequenceEqual));
 
         const ICorJitInfo::PgoInstrumentationSchema& countEntry = m_schema[*m_currentSchemaIndex];
@@ -2540,7 +2540,7 @@ PhaseStatus Compiler::fgPrepareToInstrumentMethod()
             // These are marked as [Intrinsic] only to be handled (unrolled) for constant inputs.
             // In other cases they have large managed implementations we want to profile.
             case NI_System_String_Equals:
-            case NI_System_Buffer_Memmove:
+            case NI_System_SpanHelpers_Memmove:
             case NI_System_MemoryExtensions_Equals:
             case NI_System_MemoryExtensions_SequenceEqual:
             case NI_System_MemoryExtensions_StartsWith:

src/coreclr/jit/importer.cpp

@@ -10295,9 +10295,9 @@ void Compiler::impImportBlockCode(BasicBlock* block)
                 }
 #endif
 
-                op3 = impPopStack().val; // Size
-                op2 = impPopStack().val; // Value / Src addr
-                op1 = impPopStack().val; // Dst addr
+                op3 = gtFoldExpr(impPopStack().val); // Size
+                op2 = gtFoldExpr(impPopStack().val); // Value / Src addr
+                op1 = impPopStack().val;             // Dst addr
 
                 if (op3->IsCnsIntOrI())
                 {
@@ -10343,18 +10343,34 @@ void Compiler::impImportBlockCode(BasicBlock* block)
 // TODO: enable for X86 as well, it currently doesn't support memset/memcpy helpers
 // Then, get rid of GT_STORE_DYN_BLK entirely.
 #ifndef TARGET_X86
-                    const unsigned helper = opcode == CEE_INITBLK ? CORINFO_HELP_MEMSET : CORINFO_HELP_MEMCPY;
+                    GenTreeCall* call;
+                    if (opcode == CEE_INITBLK)
+                    {
+                        // value is zero -> memzero, otherwise -> memset
+                        if (op2->IsIntegralConst(0))
+                        {
+                            call = gtNewHelperCallNode(CORINFO_HELP_MEMZERO, TYP_VOID, op1, op3);
+                        }
+                        else
+                        {
+                            call = gtNewHelperCallNode(CORINFO_HELP_MEMSET, TYP_VOID, op1, op2, op3);
+                        }
+                    }
+                    else
+                    {
+                        call = gtNewHelperCallNode(CORINFO_HELP_MEMCPY, TYP_VOID, op1, op2, op3);
+                    }
+
                     if (isVolatile)
                     {
                         // Wrap with memory barriers: full-barrier + call + load-barrier
                         impAppendTree(gtNewMemoryBarrier(), CHECK_SPILL_ALL, impCurStmtDI);
-                        impAppendTree(gtNewHelperCallNode(helper, TYP_VOID, op1, op2, op3), CHECK_SPILL_ALL,
-                                      impCurStmtDI);
+                        impAppendTree(call, CHECK_SPILL_ALL, impCurStmtDI);
                         op1 = gtNewMemoryBarrier(true);
                     }
                     else
                     {
-                        op1 = gtNewHelperCallNode(helper, TYP_VOID, op1, op2, op3);
+                        op1 = call;
                     }
 #else
                     if (opcode == CEE_INITBLK)

src/coreclr/jit/importercalls.cpp

@@ -1290,7 +1290,7 @@ var_types Compiler::impImportCall(OPCODE                  opcode,
             impAppendTree(call, verCurrentState.esStackDepth - 1, impCurStmtDI);
         }
         else if (JitConfig.JitProfileValues() && call->IsCall() &&
-                 call->AsCall()->IsSpecialIntrinsic(this, NI_System_Buffer_Memmove))
+                 call->AsCall()->IsSpecialIntrinsic(this, NI_System_SpanHelpers_Memmove))
         {
             if (opts.IsOptimizedWithProfile())
             {
@@ -1555,7 +1555,7 @@ GenTree* Compiler::impDuplicateWithProfiledArg(GenTreeCall* call, IL_OFFSET ilOf
         unsigned argNum   = 0;
         ssize_t  minValue = 0;
         ssize_t  maxValue = 0;
-        if (call->IsSpecialIntrinsic(this, NI_System_Buffer_Memmove))
+        if (call->IsSpecialIntrinsic(this, NI_System_SpanHelpers_Memmove))
         {
             // dst(0), src(1), len(2)
             argNum = 2;
@@ -2761,7 +2761,7 @@ GenTree* Compiler::impIntrinsic(GenTree*                newobjThis,
                 betterToExpand = true;
                 break;
 
-            case NI_System_Buffer_Memmove:
+            case NI_System_SpanHelpers_Memmove:
             case NI_System_SpanHelpers_SequenceEqual:
                 // We're going to instrument these
                 betterToExpand = opts.IsInstrumented();
@@ -3983,7 +3983,7 @@ GenTree* Compiler::impIntrinsic(GenTree*                newobjThis,
             case NI_System_Text_UTF8Encoding_UTF8EncodingSealed_ReadUtf8:
             case NI_System_SpanHelpers_SequenceEqual:
             case NI_System_SpanHelpers_ClearWithoutReferences:
-            case NI_System_Buffer_Memmove:
+            case NI_System_SpanHelpers_Memmove:
             {
                 if (sig->sigInst.methInstCount == 0)
                 {
@@ -8874,13 +8874,6 @@ NamedIntrinsic Compiler::lookupNamedIntrinsic(CORINFO_METHOD_HANDLE method)
                             result = NI_System_BitConverter_Int64BitsToDouble;
                         }
                     }
-                    else if (strcmp(className, "Buffer") == 0)
-                    {
-                        if (strcmp(methodName, "Memmove") == 0)
-                        {
-                            result = NI_System_Buffer_Memmove;
-                        }
-                    }
                     break;
                 }
 
@@ -9040,6 +9033,10 @@ NamedIntrinsic Compiler::lookupNamedIntrinsic(CORINFO_METHOD_HANDLE method)
                         {
                             result = NI_System_SpanHelpers_ClearWithoutReferences;
                         }
+                        else if (strcmp(methodName, "Memmove") == 0)
+                        {
+                            result = NI_System_SpanHelpers_Memmove;
+                        }
                     }
                     else if (strcmp(className, "String") == 0)
                     {