JIT: Optimize "constant_string".Length

src/coreclr/src/ToolBox/superpmi/superpmi-shared/icorjitinfoimpl.h

@@ -255,6 +255,10 @@ BOOL isValidStringRef(CORINFO_MODULE_HANDLE module, /* IN  */
                       unsigned              metaTOK /* IN  */
                       );
 
+int getStringLength(CORINFO_MODULE_HANDLE module, /* IN  */
+                    unsigned              metaTOK /* IN  */
+                    );
+
 BOOL shouldEnforceCallvirtRestriction(CORINFO_MODULE_HANDLE scope);
 
 /**********************************************************************************/

src/coreclr/src/ToolBox/superpmi/superpmi-shared/lwmlist.h

@@ -147,6 +147,7 @@ LWM(IsInstantiationOfVerifiedGeneric, DWORDLONG, DWORD)
 LWM(IsSDArray, DWORDLONG, DWORD)
 LWM(IsStructRequiringStackAllocRetBuf, DWORDLONG, DWORD)
 LWM(IsValidStringRef, DLD, DWORD)
+LWM(GetStringLength, DLD, DWORD)
 LWM(IsValidToken, DLD, DWORD)
 LWM(IsValueClass, DWORDLONG, DWORD)
 LWM(IsWriteBarrierHelperRequired, DWORDLONG, DWORD)

src/coreclr/src/ToolBox/superpmi/superpmi-shared/methodcontext.cpp

@@ -4606,6 +4606,39 @@ BOOL MethodContext::repIsValidStringRef(CORINFO_MODULE_HANDLE module, unsigned m
     return value;
 }
 
+void MethodContext::recGetStringLength(CORINFO_MODULE_HANDLE module, unsigned metaTOK, int result)
+{
+    if (GetStringLength == nullptr)
+        GetStringLength = new LightWeightMap<DLD, DWORD>();
+
+    DLD key;
+    ZeroMemory(&key, sizeof(DLD)); // We use the input structs as a key and use memcmp to compare.. so we need to zero
+                                   // out padding too
+
+    key.A = (DWORDLONG)module;
+    key.B = (DWORD)metaTOK;
+
+    GetStringLength->Add(key, (DWORD)result);
+}
+
+void MethodContext::dmpGetStringLength(DLD key, DWORD value)
+{
+    printf("GetStringLength key mod-%016llX tok-%08X, value res-%u", key.A, key.B, value);
+}
+
+int MethodContext::repGetStringLength(CORINFO_MODULE_HANDLE module, unsigned metaTOK)
+{
+    DLD key;
+    ZeroMemory(&key, sizeof(DLD)); // We use the input structs as a key and use memcmp to compare.. so we need to zero
+                                   // out padding too
+
+    key.A = (DWORDLONG)module;
+    key.B = (DWORD)metaTOK;
+
+    int value = (int)GetStringLength->Get(key);
+    return value;
+}
+
 void MethodContext::recGetHelperName(CorInfoHelpFunc funcNum, const char* result)
 {
     if (GetHelperName == nullptr)

src/coreclr/src/ToolBox/superpmi/superpmi-shared/methodcontext.h

@@ -1086,6 +1086,10 @@ class MethodContext
     void dmpIsValidStringRef(DLD key, DWORD value);
     BOOL repIsValidStringRef(CORINFO_MODULE_HANDLE module, unsigned metaTOK);
 
+    void recGetStringLength(CORINFO_MODULE_HANDLE module, unsigned metaTOK, int result);
+    void dmpGetStringLength(DLD key, DWORD value);
+    int repGetStringLength(CORINFO_MODULE_HANDLE module, unsigned metaTOK);
+
     void recGetHelperName(CorInfoHelpFunc funcNum, const char* result);
     void dmpGetHelperName(DWORD key, DWORD value);
     const char* repGetHelperName(CorInfoHelpFunc funcNum);
@@ -1352,7 +1356,7 @@ class MethodContext
 };
 
 // ********************* Please keep this up-to-date to ease adding more ***************
-// Highest packet number: 174
+// Highest packet number: 175
 // *************************************************************************************
 enum mcPackets
 {
@@ -1493,6 +1497,7 @@ enum mcPackets
     Packet_IsSDArray                                     = 101,
     Packet_IsStructRequiringStackAllocRetBuf             = 102,
     Packet_IsValidStringRef                              = 103,
+    Packet_GetStringLength                               = 175, // Added 1/7/2020
     Retired6                                             = 104,
     Packet_IsValidToken                                  = 144, // Added 7/19/2013 - adjusted members to proper types
     Packet_IsValueClass                                  = 105,

src/coreclr/src/ToolBox/superpmi/superpmi-shim-collector/icorjitinfo.cpp

@@ -517,6 +517,16 @@ BOOL interceptor_ICJI::isValidStringRef(CORINFO_MODULE_HANDLE module, /* IN  */
     return temp;
 }
 
+int interceptor_ICJI::getStringLength(CORINFO_MODULE_HANDLE module, /* IN  */
+                                      unsigned              metaTOK /* IN  */
+                                      )
+{
+    mc->cr->AddCall("getStringLength");
+    int temp = original_ICorJitInfo->getStringLength(module, metaTOK);
+    mc->recGetStringLength(module, metaTOK, temp);
+    return temp;
+}
+
 BOOL interceptor_ICJI::shouldEnforceCallvirtRestriction(CORINFO_MODULE_HANDLE scope)
 {
     mc->cr->AddCall("shouldEnforceCallvirtRestriction");

src/coreclr/src/ToolBox/superpmi/superpmi-shim-counter/icorjitinfo.cpp

@@ -378,6 +378,14 @@ BOOL interceptor_ICJI::isValidStringRef(CORINFO_MODULE_HANDLE module, /* IN  */
     return original_ICorJitInfo->isValidStringRef(module, metaTOK);
 }
 
+int interceptor_ICJI::getStringLength(CORINFO_MODULE_HANDLE module, /* IN  */
+                                      unsigned              metaTOK /* IN  */
+                                      )
+{
+    mcs->AddCall("getStringLength");
+    return original_ICorJitInfo->getStringLength(module, metaTOK);
+}
+
 BOOL interceptor_ICJI::shouldEnforceCallvirtRestriction(CORINFO_MODULE_HANDLE scope)
 {
     mcs->AddCall("shouldEnforceCallvirtRestriction");

src/coreclr/src/ToolBox/superpmi/superpmi-shim-simple/icorjitinfo.cpp

@@ -340,6 +340,13 @@ BOOL interceptor_ICJI::isValidStringRef(CORINFO_MODULE_HANDLE module, /* IN  */
     return original_ICorJitInfo->isValidStringRef(module, metaTOK);
 }
 
+int interceptor_ICJI::getStringLength(CORINFO_MODULE_HANDLE module, /* IN  */
+                                      unsigned              metaTOK /* IN  */
+                                      )
+{
+    return original_ICorJitInfo->getStringLength(module, metaTOK);
+}
+
 BOOL interceptor_ICJI::shouldEnforceCallvirtRestriction(CORINFO_MODULE_HANDLE scope)
 {
     return original_ICorJitInfo->shouldEnforceCallvirtRestriction(scope);

src/coreclr/src/ToolBox/superpmi/superpmi/icorjitinfo.cpp

@@ -408,6 +408,14 @@ BOOL MyICJI::isValidStringRef(CORINFO_MODULE_HANDLE module, /* IN  */
     return jitInstance->mc->repIsValidStringRef(module, metaTOK);
 }
 
+int MyICJI::getStringLength(CORINFO_MODULE_HANDLE module, /* IN  */
+                            unsigned              metaTOK /* IN  */
+                            )
+{
+    jitInstance->mc->cr->AddCall("getStringLength");
+    return jitInstance->mc->repGetStringLength(module, metaTOK);
+}
+
 BOOL MyICJI::shouldEnforceCallvirtRestriction(CORINFO_MODULE_HANDLE scope)
 {
     jitInstance->mc->cr->AddCall("shouldEnforceCallvirtRestriction");

src/coreclr/src/inc/corinfo.h

@@ -217,11 +217,11 @@ TODO: Talk about initializing strutures before use
 #endif
 #endif
 
-SELECTANY const GUID JITEEVersionIdentifier = { /* abcf830c-56d1-4b33-a8ec-5063bb5495f1 */
-    0xabcf830c,
-    0x56d1,
-    0x4b33,
-    {0xa8, 0xec, 0x50, 0x63, 0xbb, 0x54, 0x95, 0xf1}
+SELECTANY const GUID JITEEVersionIdentifier = { /* 13028353-152c-4886-b05b-fa76ee8169cf */
+    0x13028353,
+    0x152c,
+    0x4886,
+    {0xb0, 0x5b, 0xfa, 0x76, 0xee, 0x81, 0x69, 0xcf}
 };
 
 //////////////////////////////////////////////////////////////////////////////////////////////////////////
@@ -2307,6 +2307,11 @@ class ICorStaticInfo
             unsigned                    metaTOK     /* IN  */
             ) = 0;
 
+    virtual int getStringLength (
+            CORINFO_MODULE_HANDLE       module,     /* IN  */
+            unsigned                    metaTOK     /* IN  */
+            ) = 0;
+
     virtual BOOL shouldEnforceCallvirtRestriction(
             CORINFO_MODULE_HANDLE   scope
             ) = 0;

src/coreclr/src/jit/ICorJitInfo_API_names.h

@@ -38,6 +38,7 @@ DEF_CLR_API(getTokenTypeAsHandle)
 DEF_CLR_API(canSkipVerification)
 DEF_CLR_API(isValidToken)
 DEF_CLR_API(isValidStringRef)
+DEF_CLR_API(getStringLength)
 DEF_CLR_API(shouldEnforceCallvirtRestriction)
 DEF_CLR_API(asCorInfoType)
 DEF_CLR_API(getClassName)

src/coreclr/src/jit/ICorJitInfo_API_wrapper.hpp

@@ -367,6 +367,16 @@ BOOL WrapICorJitInfo::isValidStringRef(
     return temp;
 }
 
+int WrapICorJitInfo::getStringLength(
+            CORINFO_MODULE_HANDLE       module,     /* IN  */
+            unsigned                    metaTOK     /* IN  */)
+{
+    API_ENTER(getStringLength);
+    int temp = wrapHnd->getStringLength(module, metaTOK);
+    API_LEAVE(getStringLength);
+    return temp;
+}
+
 BOOL WrapICorJitInfo::shouldEnforceCallvirtRestriction(
             CORINFO_MODULE_HANDLE   scope)
 {

src/coreclr/src/jit/importer.cpp

@@ -3632,6 +3632,18 @@ GenTree* Compiler::impIntrinsic(GenTree*                newobjThis,
             op1 = impPopStack().val;
             if (opts.OptimizationEnabled())
             {
+                if (op1->OperIs(GT_CNS_STR))
+                {
+                    // Optimize `ldstr + String::get_Length()` to CNS_INT
+                    // e.g. "Hello".Length => 5
+                    int len = info.compCompHnd->getStringLength(
+                        op1->AsStrCon()->gtScpHnd, op1->AsStrCon()->gtSconCPX);
+                    if (len >= 0)
+                    {
+                        retNode = gtNewIconNode(len);
+                        break;
+                    }
+                }
                 GenTreeArrLen* arrLen = gtNewArrLen(TYP_INT, op1, OFFSETOF__CORINFO_String__stringLen);
                 op1                   = arrLen;
             }

src/coreclr/src/tools/Common/JitInterface/CorInfoBase.cs

@@ -369,6 +369,8 @@ unsafe partial class CorInfoImpl
         delegate uint __getExpectedTargetArchitecture(IntPtr _this, IntPtr* ppException);
         [UnmanagedFunctionPointerAttribute(default(CallingConvention))]
         delegate uint __getJitFlags(IntPtr _this, IntPtr* ppException, ref CORJIT_FLAGS flags, uint sizeInBytes);
+        [UnmanagedFunctionPointerAttribute(default(CallingConvention))]
+        delegate int __getStringLength(IntPtr _this, IntPtr* ppException, CORINFO_MODULE_STRUCT_* module, uint metaTOK);
 
         static uint _getMethodAttribs(IntPtr thisHandle, IntPtr* ppException, CORINFO_METHOD_STRUCT_* ftn)
         {
@@ -2830,11 +2832,25 @@ static uint _getJitFlags(IntPtr thisHandle, IntPtr* ppException, ref CORJIT_FLAG
             }
         }
 
+        static int _getStringLength(IntPtr thisHandle, IntPtr* ppException, CORINFO_MODULE_STRUCT_* module, uint metaTOK)
+        {
+            var _this = GetThis(thisHandle);
+            try
+            {
+                return _this.getStringLength(module, metaTOK);
+            }
+            catch (Exception ex)
+            {
+                *ppException = _this.AllocException(ex);
+                return default(int);
+            }
+        }
+
 
         static IntPtr GetUnmanagedCallbacks(out Object keepAlive)
         {
-            IntPtr * callbacks = (IntPtr *)Marshal.AllocCoTaskMem(sizeof(IntPtr) * 179);
-            Object[] delegates = new Object[179];
+            IntPtr * callbacks = (IntPtr *)Marshal.AllocCoTaskMem(sizeof(IntPtr) * 180);
+            Object[] delegates = new Object[180];
 
             var d0 = new __getMethodAttribs(_getMethodAttribs);
             callbacks[0] = Marshal.GetFunctionPointerForDelegate(d0);
@@ -3373,6 +3389,9 @@ static IntPtr GetUnmanagedCallbacks(out Object keepAlive)
             var d178 = new __getJitFlags(_getJitFlags);
             callbacks[178] = Marshal.GetFunctionPointerForDelegate(d178);
             delegates[178] = d178;
+            var d179 = new __getStringLength(_getStringLength);
+            callbacks[179] = Marshal.GetFunctionPointerForDelegate(d179);
+            delegates[179] = d179;
 
             keepAlive = delegates;
             return (IntPtr)callbacks;

src/coreclr/src/tools/Common/JitInterface/CorInfoImpl.cs

@@ -1162,6 +1162,8 @@ private bool isValidToken(CORINFO_MODULE_STRUCT_* module, uint metaTOK)
         { throw new NotImplementedException("isValidToken"); }
         private bool isValidStringRef(CORINFO_MODULE_STRUCT_* module, uint metaTOK)
         { throw new NotImplementedException("isValidStringRef"); }
+        private int getStringLength(CORINFO_MODULE_STRUCT_* module, uint metaTOK)
+        { throw new NotImplementedException("getStringLength"); }
         private bool shouldEnforceCallvirtRestriction(CORINFO_MODULE_STRUCT_* scope)
         { throw new NotImplementedException("shouldEnforceCallvirtRestriction"); }
 

src/coreclr/src/tools/Common/JitInterface/ThunkGenerator/ThunkInput.txt

@@ -342,3 +342,4 @@ FUNCTIONS
     void getModuleNativeEntryPointRange(void** pStart, void** pEnd)
     DWORD getExpectedTargetArchitecture()
     DWORD getJitFlags(CORJIT_FLAGS* flags, DWORD  sizeInBytes)
+    int getStringLength(CORINFO_MODULE_HANDLE module, unsigned metaTOK)

src/coreclr/src/tools/Common/JitInterface/ThunkGenerator/gen.bat

@@ -1,2 +1,2 @@
 cd /d %~dp0
-dotnet run -- ThunkInput.txt ..\CorInfoBase.cs ..\..\..\jitinterface\jitinterface.h
+dotnet run -- ThunkInput.txt ..\CorInfoBase.cs ..\..\..\crossgen2\jitinterface\jitinterface.h

src/coreclr/src/tools/Common/JitInterface/ThunkGenerator/gen.sh

@@ -1,3 +1,3 @@
 #!/usr/bin/env bash
 cd "$(dirname ${BASH_SOURCE[0]})"
-dotnet run -- ThunkInput.txt ../CorInfoBase.cs ../../../jitinterface/jitinterface.h
+dotnet run -- ThunkInput.txt ../CorInfoBase.cs ../../../crossgen2/jitinterface/jitinterface.h

src/coreclr/src/tools/crossgen2/jitinterface/jitinterface.h

@@ -189,6 +189,7 @@ struct JitInterfaceCallbacks
     void (* getModuleNativeEntryPointRange)(void * thisHandle, CorInfoException** ppException, void** pStart, void** pEnd);
     unsigned int (* getExpectedTargetArchitecture)(void * thisHandle, CorInfoException** ppException);
     unsigned int (* getJitFlags)(void * thisHandle, CorInfoException** ppException, void* flags, unsigned int sizeInBytes);
+    int (* getStringLength)(void * thisHandle, CorInfoException** ppException, void* module, unsigned metaTOK);
 
 };
 
@@ -1729,4 +1730,13 @@ class JitInterfaceWrapper
         return _ret;
     }
 
+    virtual int getStringLength(void* module, unsigned metaTOK)
+    {
+        CorInfoException* pException = nullptr;
+        int _ret = _callbacks->getStringLength(_thisHandle, &pException, module, metaTOK);
+        if (pException != nullptr)
+            throw pException;
+        return _ret;
+    }
+
 };

src/coreclr/src/tools/crossgen2/jitinterface/jitwrapper.cpp

@@ -27,11 +27,11 @@ class CORJIT_FLAGS
     uint64_t corJitFlags;
 };
 
-static const GUID JITEEVersionIdentifier = { /* abcf830c-56d1-4b33-a8ec-5063bb5495f1 */
-    0xabcf830c,
-    0x56d1,
-    0x4b33,
-    {0xa8, 0xec, 0x50, 0x63, 0xbb, 0x54, 0x95, 0xf1}
+static const GUID JITEEVersionIdentifier = { /* 13028353-152c-4886-b05b-fa76ee8169cf */
+    0x13028353,
+    0x152c,
+    0x4886,
+    {0xb0, 0x5b, 0xfa, 0x76, 0xee, 0x81, 0x69, 0xcf}
 };
 
 class Jit

src/coreclr/src/vm/dynamicmethod.cpp

@@ -1197,6 +1197,16 @@ LCGMethodResolver::IsValidStringRef(mdToken metaTok)
     return GetStringLiteral(metaTok) != NULL;
 }
 
+int
+LCGMethodResolver::GetStringLength(mdToken metaTok)
+{
+    STANDARD_VM_CONTRACT;
+
+    GCX_COOP();
+
+    return GetStringLiteral(metaTok)->GetStringLength();
+}
+
 //---------------------------------------------------------------------------------------
 //
 STRINGREF

src/coreclr/src/vm/dynamicmethod.h

@@ -73,6 +73,7 @@ class DynamicResolver
     // jit interface api
     virtual OBJECTHANDLE ConstructStringLiteral(mdToken metaTok) = 0;
     virtual BOOL IsValidStringRef(mdToken metaTok) = 0;
+    virtual int GetStringLength(mdToken metaTok) = 0;
     virtual void ResolveToken(mdToken token, TypeHandle * pTH, MethodDesc ** ppMD, FieldDesc ** ppFD) = 0;
     virtual SigPointer ResolveSignature(mdToken token) = 0;
     virtual SigPointer ResolveSignatureForVarArg(mdToken token) = 0;
@@ -122,6 +123,7 @@ class LCGMethodResolver : public DynamicResolver
 
     OBJECTHANDLE ConstructStringLiteral(mdToken metaTok);
     BOOL IsValidStringRef(mdToken metaTok);
+    int GetStringLength(mdToken metaTok);
     void ResolveToken(mdToken token, TypeHandle * pTH, MethodDesc ** ppMD, FieldDesc ** ppFD);
     SigPointer ResolveSignature(mdToken token);
     SigPointer ResolveSignatureForVarArg(mdToken token);

src/coreclr/src/vm/ilstubresolver.cpp

@@ -140,6 +140,13 @@ BOOL ILStubResolver::IsValidStringRef(mdToken metaTok)
     return FALSE;
 }
 
+int ILStubResolver::GetStringLength(mdToken metaTok)
+{
+    STANDARD_VM_CONTRACT;
+    _ASSERTE(FALSE);
+    return -1;
+}
+
 void ILStubResolver::ResolveToken(mdToken token, TypeHandle * pTH, MethodDesc ** ppMD, FieldDesc ** ppFD)
 {
     STANDARD_VM_CONTRACT;

src/coreclr/src/vm/ilstubresolver.h

@@ -33,6 +33,7 @@ class ILStubResolver : DynamicResolver
 
     OBJECTHANDLE ConstructStringLiteral(mdToken metaTok);
     BOOL IsValidStringRef(mdToken metaTok);
+    int GetStringLength(mdToken metaTok);
     void ResolveToken(mdToken token, TypeHandle * pTH, MethodDesc ** ppMD, FieldDesc ** ppFD);
     SigPointer ResolveSignature(mdToken token);
     SigPointer ResolveSignatureForVarArg(mdToken token);