* Add the possibility to bisect the individual transforms of SILCombine and SimplifyCFG.
To do so, the `-sil-opt-pass-count` option now accepts the format `<n>.<m>`, where `m` is the sub-pass number.
The sub-pass number limits the number of individual transforms in SILCombine or SimplifyCFG.
* Add an option `-sil-print-last` to print the SIL of the currently optimized function before and after the last pass, which is specified with `-sil-opt-pass-count`.
- If any of the `-g<kind>` flag is given -- except `-gnone`, debug
info will be printed into every generated SIL files.
- The `-gsil` is deprecated in favor of `-sil-based-debuginfo`. The
SILDebugInfoGenerator Pass now generates intermediate SIL file with
name "<output file>.sil_dbg_<n>.sil". Other functionalities of that
Pass remain the same.
* rename -sil-print-only-function to -sil-print-function and -sil-print-only-functions to -sil-print-functions
* to print single functions, don't require -Xllvm -sil-print-all. It's now sufficient to use e.g. -Xllvm -sil-print-function=<f>
But it's still possible to select functions with -sil-print-function(s) for other print options, -sil-print-after.