Reapply asan coverage changes 194702-194704.

I still don't know what is causing our bootstrapped LTO buildbots to fail,
but llvm r194701 seems to be OK and I can't imagine that these changes could
cause the problem.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@194790 91177308-0d34-0410-b5e6-96231b3b80d8
Don't build unsupported compiler-rt pieces on Windows

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@194796 91177308-0d34-0410-b5e6-96231b3b80d8
LLVM's GoogleTest copy has moved its source code back to the default
location, update this reference to reflect that.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@194802 91177308-0d34-0410-b5e6-96231b3b80d8
tsan: add proper cfi directives to assembly code
this allows gdb to unwind through our hacky call



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@194803 91177308-0d34-0410-b5e6-96231b3b80d8
[Sanitizer] Make slow unwinder on Linux more robust

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@194805 91177308-0d34-0410-b5e6-96231b3b80d8
[asan] helper script to dump/merge coverage data

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@194809 91177308-0d34-0410-b5e6-96231b3b80d8
[ASan] Add the configure+make rules for building the ASan runtime for iOS simulator.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@194813 91177308-0d34-0410-b5e6-96231b3b80d8