[sanitizer] [SystemZ] Enable TLS functionality.

[• koriakin]

Summary

This enables TLS knowledge for s390 in sanitizers.

[• koriakin]

I'm not too happy about the inline assembly in ThreadSelf. gcc supports __builtin_thread_pointer that returns exactly what's needed - maybe a better idea would be to add support for that in clang and use it here. WDYT?

[• koriakin]

In D18894#395283, @koriakin wrote:

I'm not too happy about the inline assembly in ThreadSelf. gcc supports __builtin_thread_pointer that returns exactly what's needed - maybe a better idea would be to add support for that in clang and use it here. WDYT?

Let's go with __builtin_thread_pointer - I have submitted the llvm bits in D19054 and will soon submit clang bits.

[• koriakin]

Whoops, accidentally created a new revision (D19594) instead of updating this one; abandoning.

lib/sanitizer_common/sanitizer_linux_libcdep.cc

 #endif  // !SANITIZER_FREEBSD && !SANITIZER_ANDROID && !SANITIZER_GO
 
 #if (defined(__x86_64__) || defined(__i386__) || defined(__mips__) \
-    || defined(__aarch64__) || defined(__powerpc64__)) \
+    || defined(__aarch64__) || defined(__powerpc64__) || defined(__s390__)) \
     && SANITIZER_LINUX && !SANITIZER_ANDROID
 // sizeof(struct pthread) from glibc.
 static atomic_uintptr_t kThreadDescriptorSize;

   val = 1776; // from glibc.ppc64le 2.20-8.fc21
   atomic_store(&kThreadDescriptorSize, val, memory_order_relaxed);
   return val;
+#elif defined(__s390__)
+  val = FIRST_32_SECOND_64(1152, 1776); // valid for glibc 2.22
+  atomic_store(&kThreadDescriptorSize, val, memory_order_relaxed);
 #endif
   return 0;
 }

   uptr thread_pointer;
   asm("addi %0,13,%1" : "=r"(thread_pointer) : "I"(-kTlsTcbOffset));
   descr_addr = thread_pointer - TlsPreTcbSize();
+# elif defined(__s390x__)
+  asm("ear %0, %%a0\n"
+      "sllg %0, %0, 32\n"
+      "ear %0, %%a1\n" : "=r"(descr_addr) :);
+# elif defined(__s390__)
+  asm("ear %0, %%a0\n" : "=r"(descr_addr) :);
 # else
 #  error "unsupported CPU arch"
 # endif

 #if !SANITIZER_GO
 static void GetTls(uptr *addr, uptr *size) {
 #if SANITIZER_LINUX && !SANITIZER_ANDROID
-# if defined(__x86_64__) || defined(__i386__)
+# if defined(__x86_64__) || defined(__i386__) || defined(__s390__)
   *addr = ThreadSelf();
   *size = GetTlsSize();
   *addr -= *size;