[PATCH] D11484: [compiler] [tsan] Enable tsan for aarch64

[Adhemerval Zanella]

Hi Evgeniy,

Thanks for the review.

On 24-07-2015 14:50, Evgeniy Stepanov wrote:
> eugenis added a comment.
> 
> Great job! I'll leave the real review to Dmitry. Just a few comments inline.
> 
> 
> ================
> Comment at: lib/sanitizer_common/sanitizer_linux_libcdep.cc:267
> @@ +266,3 @@
> +  val = 1776;
> +  if (val)
> +    atomic_store(&kThreadDescriptorSize, val, memory_order_relaxed);
> ----------------
> Looks like this if() is unnecessary, here and above.

Right, I will change it.

> 
> 
> ================
> Comment at: lib/sanitizer_common/sanitizer_linux_libcdep.cc:300
> @@ -288,1 +299,3 @@
> +# elif defined(__aarch64__)
> +  descr_addr = reinterpret_cast<uptr>(__builtin_thread_pointer());
>  # else
> ----------------
> Clang does not recognize this builtin on aarch64. It looks like it only exists on arm. Are you building with gcc?
> 

Yes and my mistake here (I though I have set my build to use clang). I will rebuild and
test with clang itself.  About this, it would be easier to use a asm statement, but as
pointed out clang now has the option to read  some register directly. Would be better
to add this builtin to clang instead?