This is to fix the bug in https://llvm.org/bugs/show_bug.cgi?id=27612.
When spill is hoisted to a BB with landingpad successor, and if the VNI
of the spill reg lives into the landingpad successor, the spill should be
inserted before the call which may throw exception. InsertPointAnalysis
is used to compute the safe insert point.
http://reviews.llvm.org/D20027 is a preparing patch for this patch.
Differential Revision: http://reviews.llvm.org/D19884.
llvm-svn: 269249
Wei Mi