Refactor to use llvm const types
Refactor to use llvm const types

guoyiteng/braid,cucapra/braid,cucapra/braid,cucapra/braid,cucapra/braid,guoyiteng/braid,guoyiteng/braid,guoyiteng/braid,cucapra/braid,cucapra/braid,guoyiteng/braid,guoyiteng/braid