e3e06135eb
After internal intrinsic 'spv_switch' is processed we need to delete G_BLOCK_ADDR instructions that were generated to keep track of the corresponding basic blocks. If we just delete G_BLOCK_ADDR instructions with BlockAddress operands, this leaves their BasicBlock counterparts in a "address taken" status. This would make AsmPrinter to generate a series of unneeded labels of a `"Address of block that was removed by CodeGen"` kind. This PR is to ensure that we don't have a dangling BlockAddress constants by zapping the BlockAddress nodes, and only after that proceed with erasing G_BLOCK_ADDR instructions. See also https://github.com/llvm/llvm-project/pull/87823 for more details.