llvm-project

04107209 - [LoopSimplifyCFG] Add check for missing loop preheader (#149743)

[LoopSimplifyCFG] Add check for missing loop preheader (#149743) Closes #147869 Closes #149679 Adds a check for a missing loop preheader during analysis. This fixes a nullptr dereference that happened whenever LoopSimplify was unable to generate a preheader because the loop was entered by an indirectbr instruction (as stated in the LoopSimplify.cpp doc comment).