diff --git a/eng/generators.targets b/eng/generators.targets
index bcedd85243ed33..aec6e667a6efdb 100644
--- a/eng/generators.targets
+++ b/eng/generators.targets
@@ -22,7 +22,9 @@
                         and (
                           ('@(Reference)' != ''
                             and @(Reference->AnyHaveMetadataValue('Identity', 'System.Runtime.InteropServices'))
-                            and @(Reference->AnyHaveMetadataValue('Identity', 'System.Runtime.CompilerServices.Unsafe'))
+                            and (@(Reference->AnyHaveMetadataValue('Identity', 'System.Runtime.CompilerServices.Unsafe'))
+                              or ('@(ProjectReference)' != ''
+                                and @(ProjectReference->AnyHaveMetadataValue('Identity', $([MSBuild]::NormalizePath('$(LibrariesProjectRoot)', 'System.Runtime.CompilerServices.Unsafe', 'src', 'System.Runtime.CompilerServices.Unsafe.ilproj'))))))
                             and @(Reference->AnyHaveMetadataValue('Identity', 'System.Memory')))
                           or ('@(ProjectReference)' != ''
                             and @(ProjectReference->AnyHaveMetadataValue('Identity', '$(CoreLibProject)'))))" />
diff --git a/src/libraries/Common/src/Interop/Unix/Interop.Errors.cs b/src/libraries/Common/src/Interop/Unix/Interop.Errors.cs
index 4e9b16098dcadb..88af774f71912b 100644
--- a/src/libraries/Common/src/Interop/Unix/Interop.Errors.cs
+++ b/src/libraries/Common/src/Interop/Unix/Interop.Errors.cs
@@ -183,25 +183,25 @@ internal static unsafe string StrError(int platformErrno)
         }
 
 #if SERIAL_PORTS
-        [DllImport(Libraries.IOPortsNative, EntryPoint = "SystemIoPortsNative_ConvertErrorPlatformToPal")]
-        internal static extern Error ConvertErrorPlatformToPal(int platformErrno);
+        [GeneratedDllImport(Libraries.IOPortsNative, EntryPoint = "SystemIoPortsNative_ConvertErrorPlatformToPal")]
+        internal static partial Error ConvertErrorPlatformToPal(int platformErrno);
 
-        [DllImport(Libraries.IOPortsNative, EntryPoint = "SystemIoPortsNative_ConvertErrorPalToPlatform")]
-        internal static extern int ConvertErrorPalToPlatform(Error error);
+        [GeneratedDllImport(Libraries.IOPortsNative, EntryPoint = "SystemIoPortsNative_ConvertErrorPalToPlatform")]
+        internal static partial int ConvertErrorPalToPlatform(Error error);
 
-        [DllImport(Libraries.IOPortsNative, EntryPoint = "SystemIoPortsNative_StrErrorR")]
-        private static extern unsafe byte* StrErrorR(int platformErrno, byte* buffer, int bufferSize);
+        [GeneratedDllImport(Libraries.IOPortsNative, EntryPoint = "SystemIoPortsNative_StrErrorR")]
+        private static unsafe partial byte* StrErrorR(int platformErrno, byte* buffer, int bufferSize);
 #else
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_ConvertErrorPlatformToPal")]
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_ConvertErrorPlatformToPal")]
         [SuppressGCTransition]
-        internal static extern Error ConvertErrorPlatformToPal(int platformErrno);
+        internal static partial Error ConvertErrorPlatformToPal(int platformErrno);
 
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_ConvertErrorPalToPlatform")]
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_ConvertErrorPalToPlatform")]
         [SuppressGCTransition]
-        internal static extern int ConvertErrorPalToPlatform(Error error);
+        internal static partial int ConvertErrorPalToPlatform(Error error);
 
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_StrErrorR")]
-        private static extern unsafe byte* StrErrorR(int platformErrno, byte* buffer, int bufferSize);
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_StrErrorR")]
+        private static unsafe partial byte* StrErrorR(int platformErrno, byte* buffer, int bufferSize);
 #endif
     }
 }
diff --git a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetEGid.cs b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetEGid.cs
index 87aede1e85ec05..6ee390bf8b35e7 100644
--- a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetEGid.cs
+++ b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetEGid.cs
@@ -8,7 +8,7 @@ internal static partial class Interop
 {
     internal static partial class Sys
     {
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetEGid")]
-        internal static extern uint GetEGid();
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetEGid")]
+        internal static partial uint GetEGid();
     }
 }
diff --git a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetEUid.cs b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetEUid.cs
index 1b8aa005b15ffa..f11d4efd443e14 100644
--- a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetEUid.cs
+++ b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetEUid.cs
@@ -7,7 +7,7 @@ internal static partial class Interop
 {
     internal static partial class Sys
     {
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetEUid")]
-        internal static extern uint GetEUid();
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetEUid")]
+        internal static partial uint GetEUid();
     }
 }
diff --git a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetGroups.cs b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetGroups.cs
index 2fd31563f17450..0754fabbe6d98e 100644
--- a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetGroups.cs
+++ b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetGroups.cs
@@ -44,7 +44,7 @@ internal static partial class Sys
             while (true);
         }
 
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetGroups", SetLastError = true)]
-        private static extern unsafe int GetGroups(int ngroups, uint* groups);
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetGroups", SetLastError = true)]
+        private static unsafe partial int GetGroups(int ngroups, uint* groups);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetOSArchitecture.cs b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetOSArchitecture.cs
index de7b9cd37ad2b3..50bf35c2d2cd76 100644
--- a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetOSArchitecture.cs
+++ b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetOSArchitecture.cs
@@ -9,7 +9,7 @@ internal static partial class Interop
     internal static partial class Sys
     {
         [SuppressGCTransition]
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetOSArchitecture")]
-        internal static extern int GetOSArchitecture();
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetOSArchitecture")]
+        internal static partial int GetOSArchitecture();
     }
 }
diff --git a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetProcessArchitecture.cs b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetProcessArchitecture.cs
index 2dbb0b1eed13aa..2086b4a015a118 100644
--- a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetProcessArchitecture.cs
+++ b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetProcessArchitecture.cs
@@ -9,7 +9,7 @@ internal static partial class Interop
     internal static partial class Sys
     {
         [SuppressGCTransition]
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetProcessArchitecture")]
-        internal static extern int GetProcessArchitecture();
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetProcessArchitecture")]
+        internal static partial int GetProcessArchitecture();
     }
 }
diff --git a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetSid.cs b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetSid.cs
index 6137740fc0f1f0..5b20a8660a6475 100644
--- a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetSid.cs
+++ b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetSid.cs
@@ -7,7 +7,7 @@ internal static partial class Interop
 {
     internal static partial class Sys
     {
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetSid")]
-        internal static extern int GetSid(int pid);
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetSid")]
+        internal static partial int GetSid(int pid);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetUid.cs b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetUid.cs
index 0d1bec671eaf9e..e82897460d9d83 100644
--- a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetUid.cs
+++ b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.GetUid.cs
@@ -7,7 +7,7 @@ internal static partial class Interop
 {
     internal static partial class Sys
     {
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetUid")]
-        internal static extern uint GetUid();
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_GetUid")]
+        internal static partial uint GetUid();
     }
 }
diff --git a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.RegisterForSigChld.cs b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.RegisterForSigChld.cs
index e11fcfaf0e65cd..2bbac8ac392551 100644
--- a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.RegisterForSigChld.cs
+++ b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.RegisterForSigChld.cs
@@ -7,7 +7,7 @@ internal static partial class Interop
 {
     internal static partial class Sys
     {
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_RegisterForSigChld")]
-        internal static extern unsafe void RegisterForSigChld(delegate* unmanaged<int, int, int> handler);
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_RegisterForSigChld")]
+        internal static unsafe partial void RegisterForSigChld(delegate* unmanaged<int, int, int> handler);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.SetDelayedSigChildConsoleConfigurationHandler.cs b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.SetDelayedSigChildConsoleConfigurationHandler.cs
index bd09aa12abc00d..f9c6b2be289ac3 100644
--- a/src/libraries/Common/src/Interop/Unix/System.Native/Interop.SetDelayedSigChildConsoleConfigurationHandler.cs
+++ b/src/libraries/Common/src/Interop/Unix/System.Native/Interop.SetDelayedSigChildConsoleConfigurationHandler.cs
@@ -7,8 +7,8 @@ internal static partial class Interop
 {
     internal static partial class Sys
     {
-        [DllImport(Libraries.SystemNative, EntryPoint = "SystemNative_SetDelayedSigChildConsoleConfigurationHandler")]
+        [GeneratedDllImport(Libraries.SystemNative, EntryPoint = "SystemNative_SetDelayedSigChildConsoleConfigurationHandler")]
         [SuppressGCTransition]
-        internal static extern unsafe void SetDelayedSigChildConsoleConfigurationHandler(delegate* unmanaged<void> callback);
+        internal static unsafe partial void SetDelayedSigChildConsoleConfigurationHandler(delegate* unmanaged<void> callback);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetCPInfoEx.cs b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetCPInfoEx.cs
index b0c64b5c80b4d4..773f7ddb90110e 100644
--- a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetCPInfoEx.cs
+++ b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetCPInfoEx.cs
@@ -7,8 +7,8 @@ internal static partial class Interop
 {
     internal static partial class Kernel32
     {
-        [DllImport(Libraries.Kernel32, CharSet = CharSet.Unicode, EntryPoint = "GetCPInfoExW")]
-        private static extern unsafe Interop.BOOL GetCPInfoExW(uint CodePage, uint dwFlags, CPINFOEXW* lpCPInfoEx);
+        [GeneratedDllImport(Libraries.Kernel32, EntryPoint = "GetCPInfoExW", CharSet = CharSet.Unicode)]
+        private static unsafe partial Interop.BOOL GetCPInfoExW(uint CodePage, uint dwFlags, CPINFOEXW* lpCPInfoEx);
 
         [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
         private unsafe struct CPINFOEXW
diff --git a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetConsoleCP.cs b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetConsoleCP.cs
index e76c06990b4b92..33e73f8042b77b 100644
--- a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetConsoleCP.cs
+++ b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetConsoleCP.cs
@@ -7,7 +7,7 @@ internal static partial class Interop
 {
     internal static partial class Kernel32
     {
-        [DllImport(Libraries.Kernel32)]
-        internal static extern uint GetConsoleCP();
+        [GeneratedDllImport(Libraries.Kernel32)]
+        internal static partial uint GetConsoleCP();
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetConsoleOutputCP.cs b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetConsoleOutputCP.cs
index fd59f4dddf1ca2..3d8c546dce5c18 100644
--- a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetConsoleOutputCP.cs
+++ b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetConsoleOutputCP.cs
@@ -7,7 +7,7 @@ internal static partial class Interop
 {
     internal static partial class Kernel32
     {
-        [DllImport(Libraries.Kernel32)]
-        internal static extern uint GetConsoleOutputCP();
+        [GeneratedDllImport(Libraries.Kernel32)]
+        internal static partial uint GetConsoleOutputCP();
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetNativeSystemInfo.cs b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetNativeSystemInfo.cs
index 2322bdd4d7b148..076079e0bb393e 100644
--- a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetNativeSystemInfo.cs
+++ b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetNativeSystemInfo.cs
@@ -8,7 +8,7 @@ internal static partial class Interop
 {
     internal static partial class Kernel32
     {
-        [DllImport(Libraries.Kernel32)]
-        internal static unsafe extern void GetNativeSystemInfo(SYSTEM_INFO* lpSystemInfo);
+        [GeneratedDllImport(Libraries.Kernel32)]
+        internal static unsafe partial void GetNativeSystemInfo(SYSTEM_INFO* lpSystemInfo);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetStdHandle.cs b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetStdHandle.cs
index b317b13e5499a4..501c25f54e4d7a 100644
--- a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetStdHandle.cs
+++ b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetStdHandle.cs
@@ -8,10 +8,10 @@ internal static partial class Interop
 {
     internal static partial class Kernel32
     {
-        [DllImport(Libraries.Kernel32)]
+        [GeneratedDllImport(Libraries.Kernel32)]
 #if !NO_SUPPRESS_GC_TRANSITION
         [SuppressGCTransition]
 #endif
-        internal static extern IntPtr GetStdHandle(int nStdHandle);  // param is NOT a handle, but it returns one!
+        internal static partial IntPtr GetStdHandle(int nStdHandle);  // param is NOT a handle, but it returns one!
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetSystemInfo.cs b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetSystemInfo.cs
index f3872f106180ef..383a26f280d43e 100644
--- a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetSystemInfo.cs
+++ b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.GetSystemInfo.cs
@@ -7,7 +7,7 @@ internal static partial class Interop
 {
     internal static partial class Kernel32
     {
-        [DllImport(Libraries.Kernel32)]
-        internal static unsafe extern void GetSystemInfo(SYSTEM_INFO* lpSystemInfo);
+        [GeneratedDllImport(Libraries.Kernel32)]
+        internal static unsafe partial void GetSystemInfo(SYSTEM_INFO* lpSystemInfo);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.MultiByteToWideChar.cs b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.MultiByteToWideChar.cs
index 2cd6f2b58d9102..dfb7a73c521318 100644
--- a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.MultiByteToWideChar.cs
+++ b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.MultiByteToWideChar.cs
@@ -7,8 +7,8 @@ internal static partial class Interop
 {
     internal static partial class Kernel32
     {
-        [DllImport(Libraries.Kernel32)]
-        internal static extern unsafe int MultiByteToWideChar(
+        [GeneratedDllImport(Libraries.Kernel32)]
+        internal static unsafe partial int MultiByteToWideChar(
             uint CodePage, uint dwFlags,
             byte* lpMultiByteStr, int cbMultiByte,
             char* lpWideCharStr, int cchWideChar);
diff --git a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.VerLanguageName.cs b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.VerLanguageName.cs
index 6c665a47e4955c..af062f0a4f2d0c 100644
--- a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.VerLanguageName.cs
+++ b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.VerLanguageName.cs
@@ -7,7 +7,7 @@ internal static partial class Interop
 {
     internal static partial class Kernel32
     {
-        [DllImport(Libraries.Kernel32, CharSet = CharSet.Unicode, EntryPoint = "VerLanguageNameW")]
-        internal static extern unsafe int VerLanguageName(uint wLang, char* szLang, uint cchLang);
+        [GeneratedDllImport(Libraries.Kernel32, CharSet = CharSet.Unicode, EntryPoint = "VerLanguageNameW")]
+        internal static unsafe partial int VerLanguageName(uint wLang, char* szLang, uint cchLang);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.WideCharToMultiByte.cs b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.WideCharToMultiByte.cs
index ce255b45a1fcc1..ad2d77e538c921 100644
--- a/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.WideCharToMultiByte.cs
+++ b/src/libraries/Common/src/Interop/Windows/Kernel32/Interop.WideCharToMultiByte.cs
@@ -8,8 +8,8 @@ internal static partial class Interop
 {
     internal static partial class Kernel32
     {
-        [DllImport(Libraries.Kernel32)]
-        internal static extern unsafe int WideCharToMultiByte(
+        [GeneratedDllImport(Libraries.Kernel32)]
+        internal static unsafe partial int WideCharToMultiByte(
             uint CodePage, uint dwFlags,
             char* lpWideCharStr, int cchWideChar,
             byte* lpMultiByteStr, int cbMultiByte,
diff --git a/src/libraries/Common/src/Interop/Windows/NtDll/Interop.NtQuerySystemInformation.cs b/src/libraries/Common/src/Interop/Windows/NtDll/Interop.NtQuerySystemInformation.cs
index 3c556031418b7d..6e6ef56975dbf7 100644
--- a/src/libraries/Common/src/Interop/Windows/NtDll/Interop.NtQuerySystemInformation.cs
+++ b/src/libraries/Common/src/Interop/Windows/NtDll/Interop.NtQuerySystemInformation.cs
@@ -7,8 +7,8 @@ internal static partial class Interop
 {
     internal static partial class NtDll
     {
-        [DllImport(Libraries.NtDll, ExactSpelling = true)]
-        internal static extern unsafe uint NtQuerySystemInformation(int SystemInformationClass, void* SystemInformation, uint SystemInformationLength, uint* ReturnLength);
+        [GeneratedDllImport(Libraries.NtDll, ExactSpelling = true)]
+        internal static unsafe partial uint NtQuerySystemInformation(int SystemInformationClass, void* SystemInformation, uint SystemInformationLength, uint* ReturnLength);
 
         internal const uint STATUS_INFO_LENGTH_MISMATCH = 0xC0000004;
     }
diff --git a/src/libraries/Common/src/Interop/Windows/User32/Interop.EnumWindows.cs b/src/libraries/Common/src/Interop/Windows/User32/Interop.EnumWindows.cs
index eff18b1b9d4098..c5008429fac732 100644
--- a/src/libraries/Common/src/Interop/Windows/User32/Interop.EnumWindows.cs
+++ b/src/libraries/Common/src/Interop/Windows/User32/Interop.EnumWindows.cs
@@ -8,7 +8,7 @@ internal static partial class Interop
 {
     internal static partial class User32
     {
-        [DllImport(Libraries.User32)]
-        public static extern unsafe Interop.BOOL EnumWindows(delegate* unmanaged<IntPtr, IntPtr, Interop.BOOL> callback, IntPtr extraData);
+        [GeneratedDllImport(Libraries.User32)]
+        public static unsafe partial Interop.BOOL EnumWindows(delegate* unmanaged<IntPtr, IntPtr, Interop.BOOL> callback, IntPtr extraData);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/User32/Interop.GetKeyState.cs b/src/libraries/Common/src/Interop/Windows/User32/Interop.GetKeyState.cs
index bff237b379ef65..9ee51a05404fca 100644
--- a/src/libraries/Common/src/Interop/Windows/User32/Interop.GetKeyState.cs
+++ b/src/libraries/Common/src/Interop/Windows/User32/Interop.GetKeyState.cs
@@ -7,7 +7,7 @@ internal static partial class Interop
 {
     internal static partial class User32
     {
-        [DllImport(Libraries.User32)]
-        internal static extern short GetKeyState(int virtualKeyCode);
+        [GeneratedDllImport(Libraries.User32)]
+        internal static partial short GetKeyState(int virtualKeyCode);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindow.cs b/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindow.cs
index 1ece26d7fdd6a0..3091b5c58e5af8 100644
--- a/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindow.cs
+++ b/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindow.cs
@@ -8,7 +8,7 @@ internal static partial class Interop
 {
     internal static partial class User32
     {
-        [DllImport(Libraries.User32)]
-        public static extern IntPtr GetWindow(IntPtr hWnd, int uCmd);
+        [GeneratedDllImport(Libraries.User32)]
+        public static partial IntPtr GetWindow(IntPtr hWnd, int uCmd);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindowLong.cs b/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindowLong.cs
index 1a0310987f9904..9cc34ee12fbcb0 100644
--- a/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindowLong.cs
+++ b/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindowLong.cs
@@ -8,7 +8,7 @@ internal static partial class Interop
 {
     internal static partial class User32
     {
-        [DllImport(Libraries.User32, EntryPoint = "GetWindowLongW")]
-        public static extern int GetWindowLong(IntPtr hWnd, int uCmd);
+        [GeneratedDllImport(Libraries.User32, EntryPoint = "GetWindowLongW")]
+        public static partial int GetWindowLong(IntPtr hWnd, int uCmd);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindowThreadProcessId.cs b/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindowThreadProcessId.cs
index 3b145fea4cc29c..daee2bf32eb177 100644
--- a/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindowThreadProcessId.cs
+++ b/src/libraries/Common/src/Interop/Windows/User32/Interop.GetWindowThreadProcessId.cs
@@ -8,8 +8,8 @@ internal static partial class Interop
 {
     internal static partial class User32
     {
-        [DllImport(Libraries.User32, ExactSpelling = true)]
-        public static unsafe extern int GetWindowThreadProcessId(IntPtr handle, int* processId);
+        [GeneratedDllImport(Libraries.User32, ExactSpelling = true)]
+        public static unsafe partial int GetWindowThreadProcessId(IntPtr handle, int* processId);
 
         [DllImport(Libraries.User32, ExactSpelling = true)]
         public static extern int GetWindowThreadProcessId(HandleRef handle, out int processId);
diff --git a/src/libraries/Common/src/Interop/Windows/User32/Interop.IsWindowVisible.cs b/src/libraries/Common/src/Interop/Windows/User32/Interop.IsWindowVisible.cs
index 15a829a9cf5578..c09bfb716fada2 100644
--- a/src/libraries/Common/src/Interop/Windows/User32/Interop.IsWindowVisible.cs
+++ b/src/libraries/Common/src/Interop/Windows/User32/Interop.IsWindowVisible.cs
@@ -8,7 +8,7 @@ internal static partial class Interop
 {
     internal static partial class User32
     {
-        [DllImport(Libraries.User32)]
-        public static extern BOOL IsWindowVisible(IntPtr hWnd);
+        [GeneratedDllImport(Libraries.User32)]
+        public static partial BOOL IsWindowVisible(IntPtr hWnd);
     }
 }
diff --git a/src/libraries/Common/src/Interop/Windows/User32/Interop.PostMessage.cs b/src/libraries/Common/src/Interop/Windows/User32/Interop.PostMessage.cs
index eeec1ba0b518fb..962ccd2e2be1b8 100644
--- a/src/libraries/Common/src/Interop/Windows/User32/Interop.PostMessage.cs
+++ b/src/libraries/Common/src/Interop/Windows/User32/Interop.PostMessage.cs
@@ -8,8 +8,8 @@ internal static partial class Interop
 {
     internal static partial class User32
     {
-        [DllImport(Libraries.User32, CharSet = CharSet.Unicode, ExactSpelling = true)]
-        public static extern int PostMessageW(IntPtr hwnd, int msg, IntPtr wparam, IntPtr lparam);
+        [GeneratedDllImport(Libraries.User32, CharSet = CharSet.Unicode, ExactSpelling = true)]
+        public static partial int PostMessageW(IntPtr hwnd, int msg, IntPtr wparam, IntPtr lparam);
 
         [DllImport(Libraries.User32, CharSet = CharSet.Unicode, ExactSpelling = true)]
         public static extern int PostMessageW(HandleRef hwnd, int msg, IntPtr wparam, IntPtr lparam);
diff --git a/src/libraries/Common/src/Interop/Windows/User32/Interop.SendMessageTimeout.cs b/src/libraries/Common/src/Interop/Windows/User32/Interop.SendMessageTimeout.cs
index c84dfdab7378c6..d3ebb4a04a4d9d 100644
--- a/src/libraries/Common/src/Interop/Windows/User32/Interop.SendMessageTimeout.cs
+++ b/src/libraries/Common/src/Interop/Windows/User32/Interop.SendMessageTimeout.cs
@@ -8,7 +8,7 @@ internal static partial class Interop
 {
     internal static partial class User32
     {
-        [DllImport(Libraries.User32, EntryPoint = "SendMessageTimeoutW")]
-        public static unsafe extern IntPtr SendMessageTimeout(IntPtr hWnd, int msg, IntPtr wParam, IntPtr lParam, int flags, int timeout, IntPtr* pdwResult);
+        [GeneratedDllImport(Libraries.User32, EntryPoint = "SendMessageTimeoutW")]
+        public static unsafe partial IntPtr SendMessageTimeout(IntPtr hWnd, int msg, IntPtr wParam, IntPtr lParam, int flags, int timeout, IntPtr* pdwResult);
     }
 }
diff --git a/src/libraries/System.Diagnostics.FileVersionInfo/tests/System.Diagnostics.FileVersionInfo.Tests/System.Diagnostics.FileVersionInfo.Tests.csproj b/src/libraries/System.Diagnostics.FileVersionInfo/tests/System.Diagnostics.FileVersionInfo.Tests/System.Diagnostics.FileVersionInfo.Tests.csproj
index ad027e8be25474..9b99ef0ab81242 100644
--- a/src/libraries/System.Diagnostics.FileVersionInfo/tests/System.Diagnostics.FileVersionInfo.Tests/System.Diagnostics.FileVersionInfo.Tests.csproj
+++ b/src/libraries/System.Diagnostics.FileVersionInfo/tests/System.Diagnostics.FileVersionInfo.Tests/System.Diagnostics.FileVersionInfo.Tests.csproj
@@ -3,6 +3,7 @@
     <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser</TargetFrameworks>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <IgnoreForCI Condition="'$(TargetOS)' == 'Browser'">true</IgnoreForCI>
+    <EnableDllImportGenerator>true</EnableDllImportGenerator>
   </PropertyGroup>
   <ItemGroup>
     <!-- Checked in test binaries for FileVersionInfoTest -->
@@ -41,4 +42,4 @@
   <ItemGroup>
     <ProjectReference Include="..\System.Diagnostics.FileVersionInfo.TestAssembly\System.Diagnostics.FileVersionInfo.TestAssembly.csproj" />
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/libraries/System.Net.Primitives/tests/UnitTests/System.Net.Primitives.UnitTests.Tests.csproj b/src/libraries/System.Net.Primitives/tests/UnitTests/System.Net.Primitives.UnitTests.Tests.csproj
index 077938e6ceb34e..4e77239fae9052 100644
--- a/src/libraries/System.Net.Primitives/tests/UnitTests/System.Net.Primitives.UnitTests.Tests.csproj
+++ b/src/libraries/System.Net.Primitives/tests/UnitTests/System.Net.Primitives.UnitTests.Tests.csproj
@@ -4,9 +4,10 @@
     <NoWarn>169,649</NoWarn>
     <StringResourcesPath>../../src/Resources/Strings.resx</StringResourcesPath>
     <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Browser</TargetFrameworks>
+    <EnableDllImportGenerator>true</EnableDllImportGenerator>
   </PropertyGroup>
   <PropertyGroup>
-    <!-- SYSTEM_NET_PRIMITIVES_DLL is required to allow source-level code sharing for types defined within the 
+    <!-- SYSTEM_NET_PRIMITIVES_DLL is required to allow source-level code sharing for types defined within the
          System.Net.Internals namespace. -->
     <DefineConstants>$(DefineConstants);SYSTEM_NET_PRIMITIVES_DLL</DefineConstants>
   </PropertyGroup>
@@ -106,4 +107,4 @@
     <Compile Include="$(CommonPath)Interop\Unix\System.Native\Interop.InterfaceNameToIndex.cs"
              Link="ProductionCode\Common\Interop\Unix\System.Native\Interop.InterfaceNameToIndex.cs" />
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>