Thanks for the review!

Reword warnings.

Fix commit messages.

Remove accidental trailing backslash.

Thanks for the review!

Add test.

With #1, it seems unfortunate to not be able to distinguish between a sanitize inserted __builtin_trap and code manually calling it. (Would there be an -fsanitize-trap=trap? :-)
With #2, we're worried about the generated code being noticeably worse in the unexceptional case than running without the sanitizers.

Ping, I think @samsonov was waiting on @rsmith's feedback on the following:

Remove more \briefs

clang-format, remove \brief from modified doxygen comments.

Make methods private

Doc fix, 80 col

Make option fit in 80 cols

In D12181#229467, @rsmith wrote:

In D12181#229358, @rsmith wrote:

Can you please give a brief description of the motivation for this change? When would it be appropriate to use this rather than -ftrap-function?

I'd still like an answer to this. It's not clear to me what the purpose of this is, and why you'd want a custom runtime hook for sanitizer traps but not other traps. The only time we emit a trap using -ftrap-function where there is no corresponding sanitizer is for __builtin_trap(); is the intention that you still want a normal trap for that builtin?

Use DEFINE_COMPILERRT_PRIVATE_FUNCTION in call_apsr.S, file headers.

In D12089#228583, @compnerd wrote:

Please use the DEFINE_COMPILERRT_PRIVATE_FUNCTION macros for call_apr_{d,f}.

Improve comment

Address comments

Uploading diff with arcanist.

Address most of the comments

Add and use an FNALIAS macro

In D12089#226545, @rengolin wrote:

Also, avoid using push lr / pop pc, since this behaviour doesn't work across all ARM cores. There's a macro for returning that should be used.

In D12088#226767, @danalbert wrote:

Do we need to do anything for make?

Added new files to CMakeLists.txt

Oops, I somehow managed to overlook the Done checkbox in Phabricator.

Thanks for the comments, I'll fix them up and have an updated patch shortly

In D12088#226292, @compnerd wrote:

Is there a reason to not add them to the files where the FIXME were?