[llvm] [MC] Reduce size of MCLEBFragment (NFC) (PR #75050)

[Nikita Popov via llvm-commits]

nikic wrote:

> I suggested that we can try `MCEncodedFragmentWithFixups<10, 1>, e.g. <8, 0> <8, 1> <10, 1>.`, perhaps we can just do `<8. 0>`

Yeah, I did try these separately first. For `<10, 1>` to `<8, 1>` we get -0.7% (http://llvm-compile-time-tracker.com/compare.php?from=dd32d26a37e22a3bce15ed8c21145b17ff5e1401&to=ee3fe775b7b5818de87a157dae60af8be0f0d477&stat=max-rss&linkStats=on) and for `<8, 1>` to `<8, 0>` we get -0.5% (http://llvm-compile-time-tracker.com/compare.php?from=ee3fe775b7b5818de87a157dae60af8be0f0d477&to=b4d4aba0dfbbe405f4da3494575434710f4ec9b9&stat=max-rss&linkStats=on). So both changes seem worthwhile.

https://github.com/llvm/llvm-project/pull/75050