[SelectionDAG] add ISD::BITCAST handling for isGuaranteedNotToBeUndefOrPoison#161745

yichi170 wants to merge 2 commits intollvm:mainllvm/llvm-project:mainfrom

yichi170:dag-isguaranteednottobeundef-bitcastyichi170/llvm-project:dag-isguaranteednottobeundef-bitcastCopy head branch name to clipboard