Commit Graph

4 Commits

Author SHA1 Message Date
Vedant Kumar 57faf2d208 [tsan] Don't instrument __llvm_gcov_global_state_pred or __llvm_gcda*
r274801 did not go far enough to allow gcov+tsan to cooperate. With this
commit it's possible to run the following code without false positives:

  std::thread T1(fib), T2(fib);
  T1.join(); T2.join();

llvm-svn: 276015
2016-07-19 20:16:08 +00:00
Vedant Kumar 0fdffd3709 [tsan] Try harder to not instrument gcov counters
GCOVProfiler::emitProfileArcs() can create many variables with names
starting with "__llvm_gcov_ctr", so llvm appends a numeric suffix to
most of them. Teach tsan about this.

llvm-svn: 274801
2016-07-07 22:45:28 +00:00
Vedant Kumar 0222adbcd2 [tsan] Do not instrument accesses to the gcov counters array
There is a known intended race here. This is a follow-up to r264805,
which disabled tsan instrumentation for updates to instrprof counters.
For more background on this please see the discussion in D18164.

llvm-svn: 273202
2016-06-20 21:24:26 +00:00
Anna Zaks 1a470b6f7c [tsan] Do not instrument reads/writes to instruction profile counters.
We have known races on profile counters, which can be reproduced by enabling
-fsanitize=thread and -fprofile-instr-generate simultaneously on a
multi-threaded program. This patch avoids reporting those races by not
instrumenting the reads and writes coming from the instruction profiler.

llvm-svn: 264805
2016-03-29 23:19:40 +00:00