Pull in r356809 from upstream llvm trunk (by Eli Friedman):

Pull in r356809 from upstream llvm trunk (by Eli Friedman):

  [ARM] Don't form "ands" when it isn't scheduled correctly.

  In r322972/r323136, the iteration here was changed to catch cases at
  the beginning of a basic block... but we accidentally deleted an
  important safety check.  Restore that check to the way it was.

  Fixes https://bugs.llvm.org/show_bug.cgi?id=41116

  Differential Revision: https://reviews.llvm.org/D59680

This should fix "Assertion failed: (LiveCPSR && "CPSR liveness tracking
is wrong!"), function UpdateCPSRUse" errors when building the devel/xwpe
port for armv7.

PR:		236062, 236568
MFC after:	1 month
X-MFC-With:	r344779