Implements bar.red.and.pred and bar.red.or.pred, using the undocument __ockl_wgred functions. Doesn't yet add support for numbered barriers and threadcount, as these are not needed for llm.c.
The current implementation using `winnow`'s `opt` does not work for optional arguments that are in the middle of the command. For example, `bar{.cta}.red.op.pred p, a{, b}, {!}c;`. This is because `opt` is greedy, and will always match `{, b}` instead of `,{!} c`. This change switches to using a custom combinator that handles this properly
The overarching goal is to refactor all passes so they are module-scoped and not function-scoped. Additionally, make improvements to the most egregiously buggy/unfit passes (so the code is ready for the next major features: linking, ftz handling) and continue adding more code to the LLVM backend
Replaces traditional LALRPOP-based parser with winnow-based parser to handle out-of-order instruction modifer. Generate instruction type and instruction visitor from a macro instead of writing by hand. Add separate compilation path using the new parser that only works in tests for now
