Reland "[TSan] Improve handling of stack pointer mangling in {set,long}jmp, pt.8"
Reland "[TSan] Improve handling of stack pointer mangling in {set,long}jmp, pt.8"

Fix compilation errors related to `SANITIZER_GO` `#ifdef`s.

Refine longjmp key management.  For Linux, re-implement key retrieval in
C (instead of assembly).  Removal of `InitializeGuardPtr` and a final
round of cleanups will be done in the next commit.

Reviewed By: dvyukov

Differential Revision: https://reviews.llvm.org/D64092

llvm-svn: 365513

git-svn-id: c199f293c43da69278bea8e88f92242bf3aa95f7@365560 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt,llvm-mirror/compiler-rt