[Bug sanitizer/64265] [5 Regression] r217669 broke tsan

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64265

--- Comment #12 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 34271
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34271&action=edit
gcc5-pr64265-2.patch

Incremental patch to handle the exceptions, completely untested (don't have
spare cycles for that right now), can just throw it into bootstrap/regtest.
The only complication has been in the optimization that we actually don't want
any __tsan_func_{entry,exit} calls if there are no memory accesses in the
function.