Remove the managed typemap implementation

[simonrozsival]

Description

Now that NativeAOT defaults to the trimmable typemap (#12121), the reflection-based managed typemap is no longer needed. This PR removes all traces of it. _AndroidTypeMapImplementation now accepts only llvm-ir (Mono/CoreCLR) and trimmable.

Changes

Runtime (src/Mono.Android)

• Delete ManagedTypeManager and ManagedTypeMapping.
• Remove the RuntimeFeature.ManagedTypeMap feature switch.
• Drop the managed branches in JNIEnvInit.CreateTypeManager, JNIEnv.ArrayCreateInstance, and JavaConvert (incl. their IL3050 suppression helpers).

NativeAOT host (src/Microsoft.Android.Runtime.NativeAOT)

• JreRuntime.CreateDefaultTypeManager now returns TrimmableTypeMapTypeManager unconditionally.

Generator / assembly rewriting

• Delete the ILLink TypeMappingStep (which rewrote the ManagedTypeMapping method bodies) and its registration in Microsoft.Android.Sdk.TypeMap.LlvmIr.targets.

MSBuild / SDK targets

• Remove _AndroidUseManagedTypeMap and the ManagedTypeMapRuntimeHostConfigurationOption from RuntimeConfig.targets.
• Drop managed from the _AndroidTypeMapImplementation validation in Xamarin.Android.Common.targets.
• Remove the now-dead non-trimmable NativeAOT scaffolding (ILLink-before-ILC path) from Microsoft.Android.Sdk.NativeAOT.targets.

Tests & docs

• Remove managed test cases (InstallAndRunTests, the obsolete BuildTest2.NativeAOT test).
• Update .github/copilot-instructions.md and stale comments to list only llvm-ir and trimmable.

Kept intentionally

• The llvm-ir native typemap path (TypeMapGenerator, GenerateTypeMappings, GenerateEmptyTypemapStub — the managed_to_java_map structures there are the native map's .NET→Java direction, not the managed implementation).
• XAJavaTypeScanner / XA4212 (a general IJavaObject diagnostic, not managed-specific).
• The trimmable typemap (SingleUniverseTypeMap, AggregateTypeMap, GenerateMissingTypeMapStubs, etc.).

[Copilot]

Pull request overview

This PR removes the reflection-based managed typemap implementation now that NativeAOT defaults to the trimmable typemap, and tightens _AndroidTypeMapImplementation support to only llvm-ir and trimmable. It also deletes the now-dead managed typemap ILLink step and related build/runtime plumbing.

Changes:

• Removed managed typemap runtime code (ManagedTypeManager/ManagedTypeMapping) and the RuntimeFeature.ManagedTypeMap feature switch.
• Deleted managed typemap generator/rewriter pieces (ILLink TypeMappingStep, managed marshal-method lookup table/generator, and associated MSBuild properties/targets).
• Updated targets, tests, and docs to drop managed as a supported/covered configuration.

Show a summary per file

File	Description
tests/MSBuildDeviceIntegration/Tests/InstallAndRunTests.cs	Removes managed typemap coverage and deletes a managed marshal-method lookup integration test.
src/Xamarin.Android.Build.Tasks/Xamarin.Android.Common.targets	Drops managed from _AndroidTypeMapImplementation validation; removes managed marshal-method lookup property plumbing; updates generator task parameters.
src/Xamarin.Android.Build.Tasks/Utilities/NativeCodeGenState.cs	Removes ManagedMarshalMethodsLookupInfo from build pipeline state.
src/Xamarin.Android.Build.Tasks/Utilities/MarshalMethodsNativeAssemblyGeneratorMonoVM.cs	Updates generator constructor signature after managed lookup removal.
src/Xamarin.Android.Build.Tasks/Utilities/MarshalMethodsNativeAssemblyGeneratorCoreCLR.cs	Updates generator constructor signature after managed lookup removal.
src/Xamarin.Android.Build.Tasks/Utilities/MarshalMethodsNativeAssemblyGenerator.cs	Removes managed marshal-method lookup argument path and always emits token-based get_function_pointer calls.
src/Xamarin.Android.Build.Tasks/Utilities/MarshalMethodsAssemblyRewriter.cs	Removes managed lookup generator invocation and corresponding constructor parameter.
src/Xamarin.Android.Build.Tasks/Utilities/MarshalMethodCecilAdapter.cs	Removes managed-lookup index propagation into marshal-method entry objects.
src/Xamarin.Android.Build.Tasks/Utilities/ManagedMarshalMethodsLookupInfo.cs	Deletes managed marshal-method lookup info type.
src/Xamarin.Android.Build.Tasks/Utilities/ManagedMarshalMethodsLookupGenerator.cs	Deletes managed marshal-method lookup table generator.
src/Xamarin.Android.Build.Tasks/Utilities/ApplicationConfigNativeAssemblyGeneratorCLR.cs	Removes managed marshal-method lookup flag from generated native application_config for CoreCLR.
src/Xamarin.Android.Build.Tasks/Utilities/ApplicationConfigNativeAssemblyGenerator.cs	Removes managed marshal-method lookup flag from generated native application_config for MonoVM.
src/Xamarin.Android.Build.Tasks/Utilities/ApplicationConfigCLR.cs	Removes managed marshal-method lookup field from CoreCLR application_config structure definition.
src/Xamarin.Android.Build.Tasks/Utilities/ApplicationConfig.cs	Removes managed marshal-method lookup field from MonoVM application_config structure definition.
src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/Utilities/EnvironmentHelper.cs	Updates application_config parsing field counts/cases to match native struct changes.
src/Xamarin.Android.Build.Tasks/Tasks/RewriteMarshalMethods.cs	Removes managed lookup mode/ordering logic from rewrite pipeline.
src/Xamarin.Android.Build.Tasks/Tasks/GenerateTypeMappings.cs	Updates NativeAOT comment to reflect trimmable typemap generation and skips typemap generation for NativeAOT.
src/Xamarin.Android.Build.Tasks/Tasks/GenerateNativeMarshalMethodSources.cs	Removes managed lookup task property and updates generator construction accordingly.
src/Xamarin.Android.Build.Tasks/Tasks/GenerateNativeApplicationConfigSources.cs	Removes managed marshal-method lookup option and stops emitting it into native config inputs.
src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.TypeMap.LlvmIr.targets	Removes managed-lookup task parameter and deletes the ILLink TypeMappingStep registration for managed.
src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.RuntimeConfig.targets	Removes _AndroidUseManagedTypeMap and the RuntimeFeature.ManagedTypeMap runtimeconfig option emission.
src/Xamarin.Android.Build.Tasks/Microsoft.Android.Sdk/targets/Microsoft.Android.Sdk.NativeAOT.targets	Removes non-trimmable NativeAOT scaffolding and makes the trimmable/skip-ILLink path unconditional.
src/native/mono/xamarin-app-stub/xamarin-app.hh	Removes managed marshal-method lookup flag from MonoVM application_config struct.
src/native/mono/xamarin-app-stub/application_dso_stub.cc	Removes managed marshal-method lookup flag initialization in stub config.
src/native/mono/monodroid/xamarin-android-app-context.cc	Removes placeholder get_function_pointer implementation used by the managed lookup path.
src/native/mono/monodroid/monodroid-glue.cc	Simplifies marshal-method init: always calls xamarin_app_init with startup/runtime resolver, removing managed lookup branching.
src/native/mono/monodroid/monodroid-glue-internal.hh	Removes placeholder get_function_pointer declaration.
src/native/common/include/managed-interface.hh	Removes managed marshal-method lookup flag from managed initialization args.
src/native/clr/xamarin-app-stub/application_dso_stub.cc	Removes managed marshal-method lookup flag initialization in stub config.
src/native/clr/include/xamarin-app.hh	Removes managed marshal-method lookup flag from CoreCLR application_config struct.
src/native/clr/host/host.cc	Removes passing/validation of managed marshal-method lookup enablement into managed init args.
src/Mono.Android/Mono.Android.csproj	Stops compiling managed typemap and managed marshal-method lookup table sources.
src/Mono.Android/Microsoft.Android.Runtime/RuntimeFeature.cs	Removes RuntimeFeature.ManagedTypeMap feature switch definition.
src/Mono.Android/Microsoft.Android.Runtime/ManagedTypeMapping.cs	Deletes managed typemap mapping implementation.
src/Mono.Android/Microsoft.Android.Runtime/ManagedTypeManager.cs	Deletes managed typemap type manager implementation.
src/Mono.Android/Java.Interop/ManagedMarshalMethodsLookupTable.cs	Deletes managed marshal-method lookup table entrypoint.
src/Mono.Android/Java.Interop/JavaConvert.cs	Removes managed typemap branch and its IL3050 suppression helper.
src/Mono.Android/Android.Runtime/JNIEnvInit.cs	Removes managed marshal-method lookup init path; removes managed typemap type-manager selection.
src/Mono.Android/Android.Runtime/JNIEnv.cs	Removes managed typemap dynamic array-creation fallback and suppression helper.
src/Microsoft.Android.Sdk.ILLink/TypeMappingStep.cs	Deletes the ILLink custom step that rewrote ManagedTypeMapping bodies.
src/Microsoft.Android.Runtime.NativeAOT/Java.Interop/JreRuntime.cs	Makes NativeAOT’s default type manager always TrimmableTypeMapTypeManager.
.github/copilot-instructions.md	Updates docs/examples to list only llvm-ir and trimmable.

Copilot's findings

Comments suppressed due to low confidence (1)

src/Mono.Android/Android.Runtime/JNIEnvInit.cs:151

• JnienvInitializeArgs still includes marshalMethodsEnabled, but after removing the managedMarshalMethodsLookupEnabled branch there is no longer any CoreCLR initialization path that calls xamarin_app_init to populate the generated get_function_pointer global. Repo-wide search shows xamarin_app_init(...) is only invoked from the MonoVM runtime (src/native/mono/monodroid/monodroid-glue.cc), so CoreCLR apps with marshal methods enabled will likely dereference a null function pointer in the generated marshal method stubs (or never register them correctly).

 JniRuntime.SetCurrent (androidRuntime);
RegisterTrimmableTypeMapNativeMethodsIfNeeded ();
args->propagateUncaughtExceptionFn = (IntPtr)(delegate* unmanaged<IntPtr, IntPtr, IntPtr, void>)&PropagateUncaughtException;
if (!RuntimeFeature.TrimmableTypeMap) {
args->registerJniNativesFn = GetRegisterJniNativesFnPtr ();
}

• Files reviewed: 42/42 changed files
• Comments generated: 2

[simonrozsival]

@copilot resolve the merge conflicts in this pull request

[Copilot]

@copilot resolve the merge conflicts in this pull request

Merged origin/main (commits 143d5fb59 and b367d98cd) into this branch. Two conflicts needed manual resolution:

1. GenerateNativeApplicationConfigSources.cs — kept the new AndroidEnableAssemblyStoreDecompressionCache property from main, dropped EnableManagedMarshalMethodsLookup (removed by this PR).
2. EnvironmentHelper.cs — resolved ApplicationConfigFieldCount_CoreCLR to 20 (main's 21 minus the removed managed_marshal_methods_lookup_enabled field), and fixed case 20 → case 19 for assembly_store_decompression_cache_enabled since the preceding managed marshal methods lookup field no longer exists in the struct.

Merge commit: 917a1be85.

[simonrozsival]

/review

[github-actions]

✅ Android PR Reviewer completed successfully!

[github-actions]

🤖 Code Review — Remove the managed typemap implementation

⚠️Needs Changes (one verification question) — otherwise a clean, well-scoped removal.

Summary

This PR removes the reflection-based managed typemap and the managed marshal-methods lookup table. I verified the removal is complete and internally consistent:

• No dangling references remain to ManagedTypeMap, ManagedTypeManager, ManagedTypeMapping, ManagedMarshalMethodsLookup*, managed_marshal_methods_lookup_enabled, _AndroidUseManagedTypeMap, TypeMappingStep, or get_function_pointer_placeholder across src/ and tests/.
• The managed↔native struct pairs stay in sync: the field dropped from JnienvInitializeArgs (C#) matches managed-interface.hh, and managed_marshal_methods_lookup_enabled is removed consistently from ApplicationConfig/ApplicationConfigCLR, both xamarin-app.hh headers, and both application_dso_stub.cc stubs.
• EnvironmentHelper field counts are correctly decremented (MonoVM 27→26, CoreCLR 21→20) with the trailing case branches removed and remaining cases re-indexed.
• Deleted files are removed from Mono.Android.csproj; MSBuild validation now correctly accepts only llvm-ir and trimmable.

Findings

• ⚠️1 question (inline on src/native/clr/host/host.cc): with the managed lookup gone, nothing appears to call xamarin_app_init for the CoreCLR host, so CoreCLR marshal-method function-pointer resolution may be left unwired. Please confirm CoreCLR + marshal-methods Release is covered by device-test CI. This is the only thing I'd want verified before merge.

Positives

• Excellent cleanup hygiene — dead ILLink step, feature switch, RuntimeHostConfigurationOption, and NativeAOT ILLink-before-ILC scaffolding all removed together.
• Stale comments in GenerateTypeMappings.cs updated to point at the trimmable type map instead of the deleted TypeMappingStep.
• Test matrix (InstallAndRunTests) and docs updated to drop the managed cases.

Note: GitHub combined status is currently pending/no checks reported — the Azure DevOps dotnet-android validation should be green (especially device tests) before merge.

Generated by Android PR Reviewer for #12134 · 163.4 AIC · ⌖ 18.9 AIC · ⊞ 6.8K
_{Comment /review to run again}

[github-actions]

🤖 ⚠️JNI interop — Question: how do CoreCLR marshal methods resolve their function pointer now?

Previously, for the CoreCLR host, _AndroidUseManagedMarshalMethodsLookup defaulted to true (the removed Common.targets condition enabled it for any _AndroidRuntime != 'MonoVM'), and the only thing that called xamarin_app_init for CoreCLR was the managed p/invoke in JNIEnvInit.Initialize (xamarin_app_init(args->env, &ManagedMarshalMethodsLookupTable.GetFunctionPointer)) — both removed in this PR.

The generated marshal-method bodies still go through the base MarshalMethodsNativeAssemblyGenerator.WriteBody placeholder path, which loads the get_func_ptr global set by xamarin_app_init. But unlike MonoVM (monodroid-glue.cc calls xamarin_app_init(env, get_function_pointer_at_startup)), the CoreCLR host never calls xamarin_app_init, and there is no get_function_pointer_at_startup implementation under src/native/clr/. With the managed caller gone, that callback appears to stay unset.

Can you confirm a CoreCLR + EnableMarshalMethods=true Release app is covered by device-test CI on this PR? If CoreCLR marshal methods still rely on the managed lookup, removing it here may leave the get_function_pointer callback null at runtime.

(Not blocking review approval — flagging for CI verification.)

[simonrozsival]

Marshal methods are not supported with CoreCLR (without the trimmable typemap) because there are issues with the ordering of R2R and post-trimming assembly rewriting (generating marshal methods UCO methods) in outer and inner builds...