B3::Opcode has less than one hundred cases, so it can easily fit in one byte (from two currently) This shrinks B3::Kind from 4 bytes to 2 (by removing the byte of padding at the end). This in turns eliminate padding from B3Value, shrinking it by 8 bytes (out of 80).
Created attachment 365356 [details] Patch
Comment on attachment 365356 [details] Patch r=me.
Comment on attachment 365356 [details] Patch Clearing flags on attachment: 365356 Committed r243330: <https://trac.webkit.org/changeset/243330>
All reviewed patches have been landed. Closing bug.
<rdar://problem/49124622>