cmd/compile/internal/ir: reduce size of miniExpr by 8 bytes
By moving the bit field, we can reduce the miniExpr size by
8 bytes, reducing the sizes of Exprs embedding this type.
Hopefully we get a few types to a lower memory size class.
Change-Id: I4b1d4471cf905f998b26d235980e40ca91446f45
GitHub-Last-Rev:
6dea0bd27c38d9118d13d55052efcb4070b26751
GitHub-Pull-Request: golang/go#71823
Reviewed-on: https://go-review.googlesource.com/c/go/+/650435
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>