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rattrs: Reverted attempt at merged mtree split commits

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See previous commit for why.

The merged commits surprisingly cost more than separate commit
functions. I guess because the compiler is smart enough to deduplicate
the two logic paths here:

                 code          stack          ctx
  before:       35324           2176          660
  after:        35316 (-0.0%)   2176 (+0.0%)  660 (+0.0%)

                 code          stack          ctx
  gbmap before: 38172           2192          772
  gbmap after:  38168 (-0.0%)   2192 (+0.0%)  772 (+0.0%)

The good news is this is a win for readability, I think the separate
conditions are easier to understand than a merged commit muddied with a
bunch of lfs3->mtree.r.weight == 0 checks.
This commit is contained in:
Christopher Haster
2025-12-01 15:17:28 -06:00
parent 90ba24787f
commit e29cc23acd
1 changed files with 48 additions and 35 deletions
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lfs3.c
+48 -35
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@@ -9143,28 +9143,37 @@ static int lfs3_mdir_commit_(lfs3_t *lfs3, lfs3_mdir_t *mdir,
// new mtree? // new mtree?
if (lfs3->mtree.r.weight == 0) { if (lfs3->mtree.r.weight == 0) {
lfs3_btree_init(&mtree_); lfs3_btree_init(&mtree_);
}
err = lfs3_mtree_commit(lfs3, &mtree_,
0, LFS3_RATTRS(
LFS3_RATTR(3, LFS3_TAG_MDIR, -2, LFS3_FROM_MPTR),
LFS3_RATTR_WEIGHT(+(1 << lfs3->mbits)),
LFS3_RATTR_ARG(mdir_[0].r.blocks),
LFS3_RATTR(3, LFS3_TAG_MNAME, -2, LFS3_FROM_CAT, 1),
LFS3_RATTR_WEIGHT(+(1 << lfs3->mbits)),
LFS3_RATTR_ARG(&split_name),
LFS3_RATTR(2, LFS3_TAG_MDIR, 0, LFS3_FROM_MPTR),
LFS3_RATTR_ARG(mdir_[1].r.blocks),
LFS3_RATTR_NULL));
if (err) {
goto failed;
}
// update our mtree // update our mtree
err = lfs3_mtree_commit(lfs3, &mtree_, } else {
(lfs3->mtree.r.weight == 0) err = lfs3_mtree_commit(lfs3, &mtree_,
? 0 lfs3_mbid(lfs3, mdir->mid), LFS3_RATTRS(
: lfs3_mbid(lfs3, mdir->mid), LFS3_RATTR(2, LFS3_TAG_MDIR, 0, LFS3_FROM_MPTR),
LFS3_RATTRS( LFS3_RATTR_ARG(mdir_[0].r.blocks),
LFS3_RATTR(3, LFS3_TAG_MDIR, -2, LFS3_FROM_MPTR), LFS3_RATTR(3, LFS3_TAG_MNAME, -2, LFS3_FROM_CAT, 1),
LFS3_RATTR_WEIGHT( LFS3_RATTR_WEIGHT(+(1 << lfs3->mbits)),
(lfs3->mtree.r.weight == 0) LFS3_RATTR_ARG(&split_name),
? +(1 << lfs3->mbits) LFS3_RATTR(2, LFS3_TAG_MDIR, 0, LFS3_FROM_MPTR),
: 0), LFS3_RATTR_ARG(mdir_[1].r.blocks),
LFS3_RATTR_ARG(mdir_[0].r.blocks), LFS3_RATTR_NULL));
LFS3_RATTR(3, LFS3_TAG_MNAME, -2, LFS3_FROM_CAT, 1), if (err) {
LFS3_RATTR_WEIGHT(+(1 << lfs3->mbits)), goto failed;
LFS3_RATTR_ARG(&split_name), }
LFS3_RATTR(2, LFS3_TAG_MDIR, 0, LFS3_FROM_MPTR),
LFS3_RATTR_ARG(mdir_[1].r.blocks),
LFS3_RATTR_NULL));
if (err) {
goto failed;
} }
// need to drop? // need to drop?
@@ -9210,23 +9219,27 @@ static int lfs3_mdir_commit_(lfs3_t *lfs3, lfs3_mdir_t *mdir,
// new mtree? // new mtree?
if (lfs3->mtree.r.weight == 0) { if (lfs3->mtree.r.weight == 0) {
lfs3_btree_init(&mtree_); lfs3_btree_init(&mtree_);
}
err = lfs3_mtree_commit(lfs3, &mtree_,
0, LFS3_RATTRS(
LFS3_RATTR(3, LFS3_TAG_MDIR, -2, LFS3_FROM_MPTR),
LFS3_RATTR_WEIGHT(+(1 << lfs3->mbits)),
LFS3_RATTR_ARG(mdir_[0].r.blocks),
LFS3_RATTR_NULL));
if (err) {
goto failed;
}
// update our mtree // update our mtree
err = lfs3_mtree_commit(lfs3, &mtree_, } else {
(lfs3->mtree.r.weight == 0) err = lfs3_mtree_commit(lfs3, &mtree_,
? 0 lfs3_mbid(lfs3, mdir->mid), LFS3_RATTRS(
: lfs3_mbid(lfs3, mdir->mid), LFS3_RATTR(2, LFS3_TAG_MDIR, 0, LFS3_FROM_MPTR),
LFS3_RATTRS( LFS3_RATTR_ARG(mdir_[0].r.blocks),
LFS3_RATTR(3, LFS3_TAG_MDIR, -2, LFS3_FROM_MPTR), LFS3_RATTR_NULL));
LFS3_RATTR_WEIGHT( if (err) {
(lfs3->mtree.r.weight == 0) goto failed;
? +(1 << lfs3->mbits) }
: 0),
LFS3_RATTR_ARG(mdir_[0].r.blocks),
LFS3_RATTR_NULL));
if (err) {
goto failed;
} }
} }