[PATCH] [TSan][MIPS] Adding support for MIPS64

[Alexey Samsonov]

================
Comment at: lib/tsan/rtl/tsan_interceptors.cc:661
@@ +660,3 @@
+#ifdef __mips__
+  // For mips memset gets called before a call to __cxa_guard_aquire
+  // which causes a crash in REAL(pthread_create) during initialization
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sagar wrote:
> samsonov wrote:
> > I don't understand this comment. Why does REAL(pthread_create) crash?
> As per my observation, in x86_64 first __cxa_guard_aquired() is called and its interceptor calls Initialize().
> Initialize() creates background thread.
> But in mips64 __interceptor_memset gets called before __cxa_guard_aquire() interceptor. So Initialize() is called from within __intercerptor_memset and REAL(pthread_create) emits a SIGIOT.
> 
> @dvyukov I don't know why such behaviour in mips, can you help us with this?
Why does the call to REAL(pthread_create) succeeds if it is issued from `__cxa_guard_acquired` interceptor and fails if it is issued from `memset` interceptor? I think you'd have to figure it out.

I don't see the immediate problem from your description: memset interceptor calls Initialize(), which calls InitializeIntercepotrs() (that is supposed to initialize all REAL(foo) function pointers), and only then calls internal_start_thread.

http://reviews.llvm.org/D6291