tsan: instruct malloc() to consume less memory



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@177393 91177308-0d34-0410-b5e6-96231b3b80d8
tsan: flush dead thread info earlier (when another thread is finished rather than new thread is created)



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@177394 91177308-0d34-0410-b5e6-96231b3b80d8