Pack some of IdInfo fields into a bit field

This reduces residency of compiler quite a bit on some programs.
Example stats when building T10370:

Before:

   2,871,242,832 bytes allocated in the heap
   4,693,328,008 bytes copied during GC
      33,941,448 bytes maximum residency (276 sample(s))
         375,976 bytes maximum slop
              83 MiB total memory in use (0 MB lost due to fragmentation)

After:

   2,858,897,344 bytes allocated in the heap
   4,629,255,440 bytes copied during GC
      32,616,624 bytes maximum residency (278 sample(s))
         314,400 bytes maximum slop
              80 MiB total memory in use (0 MB lost due to fragmentation)

So -3.9% residency, -1.3% bytes copied and -0.4% allocations.

Fixes #17497

Metric Decrease:
    T9233
    T9675

0 files changed, 0 insertions, 0 deletions