[CoreCLR] Remove robin-map from p/invoke override

[simonrozsival]

Summary

Removes the CoreCLR native p/invoke override dependency on external/robin-map.

The motivation is primarily dependency and code simplification, not size or startup wins. After #11537, CoreCLR no longer needs a hand-maintained BCL p/invoke table or a custom p/invoke cache in the precompiled override. CoreCLR already caches resolved p/invokes at the runtime/call-site level, and arbitrary fallback libraries can be resolved directly through the existing dotnet/android loader path.

CoreCLR now:

• has no tsl::robin_map / external/robin-map dependency
• has no custom p/invoke cache in the override
• has no generated precompiled p/invoke table or CoreCLR p/invoke-table generator
• resolves the small internal symbol set explicitly for java-interop, xa-internal-api, and liblog
• returns nullptr for BCL native libraries so CoreCLR's own resolver handles them
• falls back directly through MonodroidDl::monodroid_dlopen + monodroid_dlsym for other libraries

NativeAOT remains free of robin-map references. MonoVM keeps its existing robin-map usage.

Size impact

This is not a major app-size change. The size reduction is small but in the expected direction.

Scenario	APK/package delta	Main native payload delta
CI BuildReleaseArm64SimpleDotNet.CoreCLR.apkdesc	-32,768 bytes	shared libraries -212,128 bytes
dotnet new maui --sample-content Release/CoreCLR/R2R android-arm64	-4,096 bytes	libmonodroid.so -17,400 raw / -3,584 ZIP

The committed BuildReleaseArm64SimpleDotNet.CoreCLR.apkdesc update reflects the expected CI size-reference change.

Startup performance

No measurable startup-time difference.

Device: Samsung Galaxy A16 (SM-A165F, arm64-v8a, API 36). Method: 30 interleaved cold-start pairs using am start -W, comparing default Release/CoreCLR/R2R dotnet new maui --sample-content APKs built from main and this PR.

Variant	n	TotalTime mean	TotalTime median	p90	stdev
main	31	2289.4 ms	2272.0 ms	2312.0 ms	119.8 ms
this PR	31	2269.4 ms	2262.0 ms	2318.0 ms	35.4 ms

Paired current - main TotalTime delta across the 30 measured pairs:

n	mean	median	p90	stdev
30	+0.1 ms	-0.5 ms	+60.2 ms	51.0 ms

Conclusion: startup is unchanged within measurement noise.

Validation

• make prepare && make all on this PR
• make prepare && make all on origin/main
• dotnet new maui --sample-content Release/CoreCLR/R2R APK build on both local SDKs
• 30x interleaved startup comparison on Samsung A16 (SM-A165F, API 36)
• Earlier targeted native validation:
  • dotnet build src/native/native-clr.csproj --nologo -v:minimal -p:AndroidSupportedTargetJitAbis=arm64-v8a -p:AndroidSupportedTargetAotAbis=arm64 -p:EnableNativeAnalyzers=false
  • dotnet build src/native/native-nativeaot.csproj --nologo -v:minimal -p:AndroidSupportedTargetJitAbis=arm64-v8a -p:AndroidSupportedTargetAotAbis=arm64 -p:EnableNativeAnalyzers=false

[simonrozsival]

/review

[github-actions]

✅ Android PR Reviewer completed successfully!

[github-actions]

🤖 Android PR Review

Independent pass over the native CoreCLR p/invoke-override changes — I verified the mechanics before reading the description. The core rewrite is correct.

Verified ✅

• Symbol completeness — load_internal_symbol covers all 28 entries from the removed generated internal_pinvokes table and matches the extern "C" set in internal-pinvokes.hh; every string literal matches its identifier, nothing dropped.
• Library-name matching — the new == "java-interop" / "xa-internal-api" / "liblog" / "libSystem.*" comparisons are exactly the strings the deleted generator hashed into the old *_hash constants. Behavior-equivalent.
• handle_jni_on_load removal — dead code on the CLR path (no callers; Java_JNI_OnLoad in clr/host/host.cc never used it). NativeAOT keeps its own live copy. Clean.
• robin-map removal — every remaining ROBIN_MAP_DIR / tsl:: reference is confined to src/native/mono/ under the new if(IS_MONO_RUNTIME) guard; no dangling references anywhere in src/native/clr/.
• Cache removal — relying on CoreCLR's per-method p/invoke caching is sound, and build-time-known DSOs are still handle-cached inside monodroid_dlopen, so dropping other_pinvoke_map causes no meaningful dlopen refcount regression.
• Tabs/formatting, added includes, and inline macros all look correct.

Non-blocking suggestions 💡 (inline)

1. load_internal_symbol reintroduces a hand-maintained table with the same drift → abort_application failure mode this PR removes for the BCL libs (#11530). Worth a static_assert/cross-reference guard.
2. Test coverage gap — the only test targets libmonosgen-2.0 (MonoVM-only), so the rewritten CoreCLR fallback path has no on-device coverage.

CI

Checks are still pending on 00428d9 (draft PR) — I could not confirm green. Please make sure the CoreCLR and NativeAOT native builds plus the on-device p/invoke tests pass before merging.

---

Verdict: No blocking code issues found — 2 optional suggestions above. Nice cleanup: −633/+143 and one fewer external dependency on the CoreCLR path. 👍 (Confirm CI is green before un-drafting.)

Generated by Android PR Reviewer for #12010 · 383.9 AIC · ⌖ 27.3 AIC · ⊞ 6.8K
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[Copilot]

Pull request overview

This PR simplifies the CoreCLR native p/invoke override by removing the robin-map dependency and the custom p/invoke cache/table, relying instead on explicit handling for a small set of internal symbols plus the existing dotnet/android loader fallback for other libraries.

Changes:

• Remove CoreCLR’s robin-map-based p/invoke cache and associated include/compile plumbing.
• Replace the CoreCLR precompiled override’s generated internal table with explicit per-library symbol resolution, and route “other” libraries through MonodroidDl::monodroid_dlopen/monodroid_dlsym.
• Update size reference (*.apkdesc) and adjust test commentary accordingly.

Show a summary per file

File	Description
tests/Mono.Android-Tests/Mono.Android-Tests/Android.Runtime/PInvokeOverrideTests.cs	Updates test commentary to reflect new fallback resolution (no robin-map cache).
src/Xamarin.Android.Build.Tasks/Tests/Xamarin.ProjectTools/Resources/Base/BuildReleaseArm64SimpleDotNet.CoreCLR.apkdesc	Updates expected size baselines for CoreCLR build artifacts.
src/native/CMakeLists.txt	Makes ROBIN_MAP_DIR conditional on Mono runtime builds only.
src/native/clr/pinvoke-override/precompiled.cc	Reworks precompiled CoreCLR override to explicit symbol handling + loader fallback; removes generated include usage.
src/native/clr/pinvoke-override/pinvoke-tables.include	Deletes the generated CoreCLR internal-pinvoke table include.
src/native/clr/pinvoke-override/generate-pinvoke-tables.cc	Removes the CoreCLR pinvoke table generator source.
src/native/clr/pinvoke-override/dynamic.cc	Simplifies dynamic override path and routes unknown libraries via load_library_symbol.
src/native/clr/pinvoke-override/CMakeLists.txt	Removes robin-map include paths and compile definitions.
src/native/clr/include/host/pinvoke-override.hh	Removes robin-map types/caching and narrows the public API to load_library_symbol + override entrypoint.
src/native/clr/include/host/pinvoke-override-impl.hh	Removes robin-map caching logic; keeps direct dlopen/dlsym-based resolution via MonodroidDl.
src/native/clr/host/CMakeLists.txt	Drops robin-map include directories from CoreCLR host build.
.gitignore	Removes ignore entries for deleted CoreCLR pinvoke generator artifacts.

Copilot's findings

• Files reviewed: 11/12 changed files
• Comments generated: 1