[clang] [Clang][AArch64] Fix crash with large arguments to MTE built-ins (PR #197620)

[Igor Kudrin via cfe-commits]

igorkudrin wrote:

> Doesn't CheckImplicitConversions() normally get called later through CheckCompletedExpr()?

Maybe it doesn't walk through all the parameters of `CallExpr`. The diagnostic is only produced for the return type, unless I add `CheckImplicitConversion()` explicitly in `SemaARM::BuiltinARMMemoryTaggingCall()`.

> Anyway, the helper you want is probably convertArgumentToType().

This is a static function in `clang/lib/Sema/SemaChecking.cpp` and is not available in `clang/lib/Sema/SemaARM.cpp`. And while it does add all the required implicit conversions, it still does not produce the diagnostics.

https://github.com/llvm/llvm-project/pull/197620