After watching a few different people get confused about nameless blocks in llvm IR, and recalling my own confusion a few years ago, I’d like to change the syntax slightly to make it a bit clearer.
This is similar to the change made for instruction names in https://llvm.org/PR2480 a decade ago.
- Change the parsing of a numeric block label to parse as a value number rather than a string.
- When printing blocks, always print the value number as a proper label, except for the initial block.
See proposed change in https://reviews.llvm.org/D58548