[PATCH] [dfsan] Introduce dfsan_read_label runtime function.

[Evgeniy Stepanov]

================
Comment at: lib/dfsan/lit_tests/basic.c:16
@@ -15,1 +15,3 @@
 
+  dfsan_label read_label = dfsan_read_label(&i, sizeof(i));
+  assert(i_label == read_label);
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Please add a test for union behavior of dfsan_read_label (i.e. a memory range with different labels).


http://llvm-reviews.chandlerc.com/D1349