[interp] Implement pinned IL locals (#118975)

Implements pinned IL locals in the interpreter

Author: kg

src/coreclr/interpreter/compiler.cpp

@@ -1111,6 +1111,9 @@ void InterpCompiler::BuildGCInfo(InterpMethod *pInterpMethod)
                     continue;
             }
 
+            if (pVar->pinned)
+                flags = (GcSlotFlags)(flags | GC_SLOT_PINNED);
+
             if (pass == 0)
                 slotAllocator.AllocateOrReuseGcSlot(pVar->offset, flags);
             else
@@ -1520,9 +1523,11 @@ void InterpCompiler::CreateILVars()
 
     for (int i = 0; i < numILLocals; i++) {
         CORINFO_CLASS_HANDLE argClass;
-        CorInfoType argCorType = strip(m_compHnd->getArgType(&m_methodInfo->locals, sigArg, &argClass));
+        CorInfoTypeWithMod argCorTypeWithFlags = m_compHnd->getArgType(&m_methodInfo->locals, sigArg, &argClass);
+        CorInfoType argCorType = strip(argCorTypeWithFlags);
+        bool pinned = (argCorTypeWithFlags & CORINFO_TYPE_MOD_PINNED) == CORINFO_TYPE_MOD_PINNED;
         InterpType interpType = GetInterpType(argCorType);
-        CreateNextLocalVar(index, argClass, interpType, &offset);
+        CreateNextLocalVar(index, argClass, interpType, &offset, pinned);
         sigArg = m_compHnd->getArgNext(sigArg);
         index++;
     }
@@ -1550,7 +1555,7 @@ void InterpCompiler::CreateILVars()
     m_totalVarsStackSize = offset;
 }
 
-void InterpCompiler::CreateNextLocalVar(int iArgToSet, CORINFO_CLASS_HANDLE argClass, InterpType interpType, int32_t *pOffset)
+void InterpCompiler::CreateNextLocalVar(int iArgToSet, CORINFO_CLASS_HANDLE argClass, InterpType interpType, int32_t *pOffset, bool pinned)
 {
     int32_t align;
     int32_t size = GetInterpTypeStackSize(argClass, interpType, &align);
@@ -1562,6 +1567,7 @@ void InterpCompiler::CreateNextLocalVar(int iArgToSet, CORINFO_CLASS_HANDLE argC
     m_pVars[iArgToSet].size = size;
     *pOffset = ALIGN_UP_TO(*pOffset, align);
     m_pVars[iArgToSet].offset = *pOffset;
+    m_pVars[iArgToSet].pinned = pinned;
     INTERP_DUMP("alloc arg var %d to offset %d\n", iArgToSet, *pOffset);
     *pOffset += size;
 }
@@ -5315,7 +5321,7 @@ void InterpCompiler::GenerateCode(CORINFO_METHOD_INFO* methodInfo)
                 int byrefOfTypedRefVar = m_pStackPointer[-1].var;
                 m_pLastNewIns->SetDVar(byrefOfTypedRefVar);
                 m_pStackPointer--;
-                
+
                 AddIns(GetStindForType(InterpTypeByRef));
                 m_pLastNewIns->data[0] = OFFSETOF__CORINFO_TypedReference__dataPtr;
                 m_pLastNewIns->SetSVars2(byrefOfTypedRefVar, addressVar);
@@ -5380,7 +5386,7 @@ void InterpCompiler::GenerateCode(CORINFO_METHOD_INFO* methodInfo)
                         m_pLastNewIns->data[2] = 0;
                         m_pLastNewIns->SetSVar(typedByRefVar);
                         m_pLastNewIns->SetDVar(classHandleVar);
-                        
+
                         AddIns(INTOP_CALL_HELPER_P_S);
                         m_pLastNewIns->data[0] = GetDataForHelperFtn(CORINFO_HELP_TYPEHANDLE_TO_RUNTIMETYPEHANDLE_MAYBENULL);
                         m_pLastNewIns->SetSVar(classHandleVar);

src/coreclr/interpreter/compiler.h

@@ -359,6 +359,7 @@ struct InterpVar
     unsigned int global : 1; // Dedicated stack offset throughout method execution
     unsigned int ILGlobal : 1; // Args and IL locals
     unsigned int alive : 1; // Used internally by the var offset allocator
+    unsigned int pinned : 1; // Indicates that the var had the 'pinned' modifier in IL
 
     InterpVar(InterpType interpType, CORINFO_CLASS_HANDLE clsHnd, int size)
     {
@@ -374,6 +375,7 @@ struct InterpVar
         global = false;
         ILGlobal = false;
         alive = false;
+        pinned = false;
     }
 };
 
@@ -683,7 +685,7 @@ class InterpCompiler
     int32_t GetInterpTypeStackSize(CORINFO_CLASS_HANDLE clsHnd, InterpType interpType, int32_t *pAlign);
     void    CreateILVars();
 
-    void CreateNextLocalVar(int iArgToSet, CORINFO_CLASS_HANDLE argClass, InterpType interpType, int32_t *pOffset);
+    void CreateNextLocalVar(int iArgToSet, CORINFO_CLASS_HANDLE argClass, InterpType interpType, int32_t *pOffset, bool pinned = false);
 
     // Stack
     StackInfo *m_pStackPointer, *m_pStackBase;