Fix some contracts and a bug in args by ref introduced in a previous commit

Author: janvorli

src/coreclr/vm/callstubgenerator.cpp

@@ -543,15 +543,9 @@ extern "C" void CallJittedMethodRet4Float(PCODE *routines, int8_t*pArgs, int8_t*
 // The returned call stub header must be freed by the caller using FreeCallStub.
 CallStubHeader *CallStubGenerator::GenerateCallStub(MethodDesc *pMD)
 {
-    CONTRACTL
-    {
-        NOTHROW;
-        MODE_ANY;
-        GC_NOTRIGGER;
-        FORBID_FAULT;
-        PRECONDITION(CheckPointer(pMD));
-    }
-    CONTRACTL_END
+    STANDARD_VM_CONTRACT;
+
+    _ASSERTE(pMD != NULL);
 
     MetaSig sig(pMD);
     ArgIterator argIt(&sig);
@@ -984,20 +978,20 @@ void CallStubGenerator::ProcessArgument(ArgIterator& argIt, ArgLocDesc& argLocDe
             m_s1 = NoRange;
         }
 #endif // TARGET_APPLE && TARGET_ARM64
+    }
 
 #ifndef UNIX_AMD64_ABI
-        // Arguments passed by reference are handled separately, because the interpreter stores the value types on its stack by value.
-        // So the argument loading routine needs to load the address of the argument. To avoid explosion of number of the routines,
-        // we always process single argument passed by reference using single routine.
-        if (argIt.IsArgPassedByRef())
-        {
-            _ASSERTE(argLocDesc.m_cGenReg == 1);
-            routines[m_routineIndex++] = GetGPRegRefLoadRoutine(argLocDesc.m_idxGenReg);
-            routines[m_routineIndex++] = argIt.GetArgSize();
-            m_r1 = NoRange;
-        }
-#endif // UNIX_AMD64_ABI        
+    // Arguments passed by reference are handled separately, because the interpreter stores the value types on its stack by value.
+    // So the argument loading routine needs to load the address of the argument. To avoid explosion of number of the routines,
+    // we always process single argument passed by reference using single routine.
+    if (argIt.IsArgPassedByRef())
+    {
+        _ASSERTE(argLocDesc.m_cGenReg == 1);
+        routines[m_routineIndex++] = GetGPRegRefLoadRoutine(argLocDesc.m_idxGenReg);
+        routines[m_routineIndex++] = argIt.GetArgSize();
+        m_r1 = NoRange;
     }
+#endif // UNIX_AMD64_ABI
 }
 
 // Free the call stub header generated by GenerateCallStub.

src/coreclr/vm/interpexec.cpp

@@ -13,9 +13,7 @@ void InvokeCompiledMethod(MethodDesc *pMD, int8_t *pArgs, int8_t *pRet)
     CONTRACTL
     {
         THROWS;
-        MODE_COOPERATIVE;
-        GC_NOTRIGGER;
-        FORBID_FAULT;
+        MODE_ANY;
         PRECONDITION(CheckPointer(pMD));
         PRECONDITION(CheckPointer(pArgs));
         PRECONDITION(CheckPointer(pRet));