Optimize GetType with known type

src/coreclr/jit/compiler.h

@@ -4068,6 +4068,9 @@ class Compiler
                           GenTree**            clone,
                           unsigned             curLevel,
                           Statement** pAfterStmt DEBUGARG(const char* reason));
+
+    CORINFO_CLASS_HANDLE impImportHandleFromStack(bool allowShared);
+
     GenTree* impStoreStruct(GenTree*         store,
                              unsigned         curLevel,
                              Statement**      pAfterStmt = nullptr,

src/coreclr/jit/importer.cpp

@@ -2039,6 +2039,45 @@ GenTree* Compiler::impCloneExpr(GenTree*    tree,
     return gtNewLclvNode(temp, type);
 }
 
+//------------------------------------------------------------------------
+// impImportHandleFromStack: Imports the tree on the top of the stack
+//    and extracts the handle from it
+//
+// Arguments:
+//    allowShared - whether shared types are considered as valid handles
+//
+// Return Value:
+//    The extracted handle, or NO_CLASS_HANDLE if no handle could be extracted
+//
+CORINFO_CLASS_HANDLE Compiler::impImportHandleFromStack(bool allowShared)
+{
+    GenTree*             tree    = impStackTop().val;
+    bool                 isExact = false;
+    bool                 notNull = false;
+    CORINFO_CLASS_HANDLE typeHnd = gtGetClassHandle(tree, &isExact, &notNull);
+    if ((typeHnd != NO_CLASS_HANDLE) && isExact)
+    {
+        assert((info.compCompHnd->getClassAttribs(typeHnd) & CORINFO_FLG_GENERIC_TYPE_VARIABLE) == 0);
+        if (!allowShared && ((info.compCompHnd->getClassAttribs(typeHnd) & CORINFO_FLG_SHAREDINST) != 0))
+        {
+            return NO_CLASS_HANDLE;
+        }
+
+        JITDUMP("Retuning a constant handle from imported tree\n");
+        impPopStack();
+        if (!notNull && fgAddrCouldBeNull(tree))
+        {
+            impAppendTree(gtNewNullCheck(tree, compCurBB), CHECK_SPILL_ALL, impCurStmtDI);
+        }
+        else if ((tree->gtFlags & GTF_SIDE_EFFECT) != 0)
+        {
+            impAppendTree(gtUnusedValNode(tree), CHECK_SPILL_ALL, impCurStmtDI);
+        }
+        return typeHnd;
+    }
+    return NO_CLASS_HANDLE;
+}
+
 //------------------------------------------------------------------------
 // impCreateDIWithCurrentStackInfo: Create a DebugInfo instance with the
 // specified IL offset and 'is call' bit, using the current stack to determine

src/coreclr/jit/importercalls.cpp

@@ -3561,6 +3561,18 @@ GenTree* Compiler::impIntrinsic(GenTree*                newobjThis,
                     }
                 }
 
+                // Load handle directly for known types
+                if (retNode == nullptr)
+                {
+                    CORINFO_CLASS_HANDLE typeHnd = impImportHandleFromStack(false);
+                    if (typeHnd != NO_CLASS_HANDLE)
+                    {
+                        JITDUMP("Optimizing object.GetType() with known type to typeof\n");
+                        GenTree* handle = gtNewIconEmbClsHndNode(typeHnd);
+                        retNode         = gtNewHelperCallNode(CORINFO_HELP_TYPEHANDLE_TO_RUNTIMETYPE, TYP_REF, handle);
+                    }
+                }
+
 #ifdef DEBUG
                 if (retNode != nullptr)
                 {

src/tests/readytorun/tests/generics.cs

@@ -3073,13 +3073,17 @@ public static class Assert
 {
     public static bool HasAssertFired;
 
+    [MethodImplAttribute(MethodImplOptions.NoInlining)]
     public static void AreEqual(Object actual, Object expected)
     {
-        if (!(actual == null && expected == null) && !actual.Equals(expected))
+        if (ReferenceEquals(expected, actual))
+            return;
+
+        if (ReferenceEquals(expected, null) || !expected.Equals(actual))
         {
             Console.WriteLine("Not equal!");
-            Console.WriteLine("actual   = " + actual.ToString());
-            Console.WriteLine("expected = " + expected.ToString());
+            Console.WriteLine("expected = " + expected?.ToString());
+            Console.WriteLine("actual   = " + actual?.ToString());
             HasAssertFired = true;
         }
     }

src/tests/readytorun/tests/main.cs

@@ -278,7 +278,9 @@ static void TestChangingHFAStruct()
     [MethodImplAttribute(MethodImplOptions.NoInlining)]
     static void TestGetType()
     {
-        new MyClass().GetType().ToString();
+        NoInline(new MyClass()).GetType().ToString();
+        [MethodImplAttribute(MethodImplOptions.NoInlining)]
+        static object NoInline(object o) => o;
     }
 
     [MethodImplAttribute(MethodImplOptions.NoInlining)]
@@ -393,17 +395,17 @@ static void GenericLdtokenFieldsTest()
             string expectedDllField4 = "System.Collections.Generic.KeyValuePair`2[???,System.Int32] MyGeneric`2[???,???]::m_Field4".Replace("???", instArg.ToString());
             string expectedDllField5 = "System.Int32 MyGeneric`2[???,???]::m_Field5".Replace("???", instArg.ToString());
 
-            Assert.AreEqual(expectedField1, FieldFullName(getter.GetGenT_Field1()));
-            Assert.AreEqual(expectedField2, FieldFullName(getter.GetGenT_Field2()));
-            Assert.AreEqual(expectedField3, FieldFullName(getter.GetGenT_Field3()));
-            Assert.AreEqual(expectedField4, FieldFullName(getter.GetGenT_Field4()));
-            Assert.AreEqual(expectedField5, FieldFullName(getter.GetGenT_Field5()));
-
-            Assert.AreEqual(expectedDllField1, FieldFullName(getter.GetGenDllT_Field1()));
-            Assert.AreEqual(expectedDllField2, FieldFullName(getter.GetGenDllT_Field2()));
-            Assert.AreEqual(expectedDllField3, FieldFullName(getter.GetGenDllT_Field3()));
-            Assert.AreEqual(expectedDllField4, FieldFullName(getter.GetGenDllT_Field4()));
-            Assert.AreEqual(expectedDllField5, FieldFullName(getter.GetGenDllT_Field5()));
+            Assert.AreEqual(FieldFullName(getter.GetGenT_Field1()), expectedField1);
+            Assert.AreEqual(FieldFullName(getter.GetGenT_Field2()), expectedField2);
+            Assert.AreEqual(FieldFullName(getter.GetGenT_Field3()), expectedField3);
+            Assert.AreEqual(FieldFullName(getter.GetGenT_Field4()), expectedField4);
+            Assert.AreEqual(FieldFullName(getter.GetGenT_Field5()), expectedField5);
+
+            Assert.AreEqual(FieldFullName(getter.GetGenDllT_Field1()), expectedDllField1);
+            Assert.AreEqual(FieldFullName(getter.GetGenDllT_Field2()), expectedDllField2);
+            Assert.AreEqual(FieldFullName(getter.GetGenDllT_Field3()), expectedDllField3);
+            Assert.AreEqual(FieldFullName(getter.GetGenDllT_Field4()), expectedDllField4);
+            Assert.AreEqual(FieldFullName(getter.GetGenDllT_Field5()), expectedDllField5);
         }
     }
 
@@ -438,7 +440,7 @@ static void TestILBodyChange()
     {
         int actualMethodCallResult = (int)typeof(ILInliningTest).GetMethod("TestDifferentIntValue").Invoke(null, new object[]{});
         Console.WriteLine(actualMethodCallResult);
-        Assert.AreEqual(ILInliningTest.TestDifferentIntValue(), actualMethodCallResult);
+        Assert.AreEqual(actualMethodCallResult, ILInliningTest.TestDifferentIntValue());
     }
 
     static void RunAllTests()

src/tests/readytorun/tests/newarray.cs

@@ -112,13 +112,17 @@ public static class Assert
 {
     public static bool HasAssertFired;
 
+    [MethodImplAttribute(MethodImplOptions.NoInlining)]
     public static void AreEqual(Object actual, Object expected)
     {
-        if (!(actual == null && expected == null) && !actual.Equals(expected))
+        if (ReferenceEquals(expected, actual))
+            return;
+
+        if (ReferenceEquals(expected, null) || !expected.Equals(actual))
         {
             Console.WriteLine("Not equal!");
-            Console.WriteLine("actual   = " + actual.ToString());
-            Console.WriteLine("expected = " + expected.ToString());
+            Console.WriteLine("expected = " + expected?.ToString());
+            Console.WriteLine("actual   = " + actual?.ToString());
             HasAssertFired = true;
         }
     }

src/tests/readytorun/tests/test.cs

@@ -14,13 +14,17 @@ public static class Assert
 {
     public static bool HasAssertFired;
 
+    [MethodImplAttribute(MethodImplOptions.NoInlining)]
     public static void AreEqual(Object actual, Object expected)
     {
-        if (!(actual == null && expected == null) && !actual.Equals(expected))
+        if (ReferenceEquals(expected, actual))
+            return;
+
+        if (ReferenceEquals(expected, null) || !expected.Equals(actual))
         {
             Console.WriteLine("Not equal!");
-            Console.WriteLine("actual   = " + actual.ToString());
-            Console.WriteLine("expected = " + expected.ToString());
+            Console.WriteLine("expected = " + expected?.ToString());
+            Console.WriteLine("actual   = " + actual?.ToString());
             HasAssertFired = true;
         }
     }
@@ -623,8 +627,6 @@ static void TestMovedGenericVirtualMethod()
         Assert.AreEqual(o.ChangedToVirtual<WeakReference>(), typeof(List<WeakReference>).ToString());
     }
 
-
-
     [MethodImplAttribute(MethodImplOptions.NoInlining)]
     static void TestMovedGenericVirtualMethodOnNullReference()
     {
@@ -729,7 +731,9 @@ static void TestChangingHFAStruct()
     [MethodImplAttribute(MethodImplOptions.NoInlining)]
     static void TestGetType()
     {
-        new MyClass().GetType().ToString();
+        NoInline(new MyClass()).GetType().ToString();
+        [MethodImplAttribute(MethodImplOptions.NoInlining)]
+        static object NoInline(object o) => o;
     }
 
     [MethodImplAttribute(MethodImplOptions.NoInlining)]
@@ -848,17 +852,17 @@ static void TestGenericLdtokenFields()
             string expectedDllField4 = "System.Collections.Generic.KeyValuePair`2[???,System.Int32] MyGeneric`2[???,???]::m_Field4".Replace("???", instArg.ToString());
             string expectedDllField5 = "System.Int32 MyGeneric`2[???,???]::m_Field5".Replace("???", instArg.ToString());
 
-            Assert.AreEqual(expectedField1, FieldFullName(getter.GetGenT_Field1()));
-            Assert.AreEqual(expectedField2, FieldFullName(getter.GetGenT_Field2()));
-            Assert.AreEqual(expectedField3, FieldFullName(getter.GetGenT_Field3()));
-            Assert.AreEqual(expectedField4, FieldFullName(getter.GetGenT_Field4()));
-            Assert.AreEqual(expectedField5, FieldFullName(getter.GetGenT_Field5()));
-
-            Assert.AreEqual(expectedDllField1, FieldFullName(getter.GetGenDllT_Field1()));
-            Assert.AreEqual(expectedDllField2, FieldFullName(getter.GetGenDllT_Field2()));
-            Assert.AreEqual(expectedDllField3, FieldFullName(getter.GetGenDllT_Field3()));
-            Assert.AreEqual(expectedDllField4, FieldFullName(getter.GetGenDllT_Field4()));
-            Assert.AreEqual(expectedDllField5, FieldFullName(getter.GetGenDllT_Field5()));
+            Assert.AreEqual(FieldFullName(getter.GetGenT_Field1()), expectedField1);
+            Assert.AreEqual(FieldFullName(getter.GetGenT_Field2()), expectedField2);
+            Assert.AreEqual(FieldFullName(getter.GetGenT_Field3()), expectedField3);
+            Assert.AreEqual(FieldFullName(getter.GetGenT_Field4()), expectedField4);
+            Assert.AreEqual(FieldFullName(getter.GetGenT_Field5()), expectedField5);
+
+            Assert.AreEqual(FieldFullName(getter.GetGenDllT_Field1()), expectedDllField1);
+            Assert.AreEqual(FieldFullName(getter.GetGenDllT_Field2()), expectedDllField2);
+            Assert.AreEqual(FieldFullName(getter.GetGenDllT_Field3()), expectedDllField3);
+            Assert.AreEqual(FieldFullName(getter.GetGenDllT_Field4()), expectedDllField4);
+            Assert.AreEqual(FieldFullName(getter.GetGenDllT_Field5()), expectedDllField5);
         }
     }
 
@@ -888,7 +892,7 @@ private static void ValidateTestHasCrossModuleImplementation(string testName, Li
                 found = true;
         }
         Console.WriteLine($"Found:{found}");
-        Assert.AreEqual(expectedToBePresent, found);
+        Assert.AreEqual(found, expectedToBePresent);
     }
 
     public static void RunAllTests(Assembly assembly)
@@ -1012,4 +1016,4 @@ public static void RunAllTests(Assembly assembly)
     }
 
     static int s;
-}
+}