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Dropped grm-specific gdelta functions

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Yes these offered a tiny bit of typing savings, but they are used so
infrequently (really just lfsr_mdir_commit and friends) that they aren't
really worth it.

They also sort of break the object-related function pattern, since they
operated gdeltas (uint8_t[]) instead of grms (lfsr_grm_t). It's easy
enough to pass LFSR_GRM_DSIZE where needed.

This would probably only get worse if we add more gstate types.

This had no impact on code/stack. These functions were probably already
inlined.
This commit is contained in:
Christopher Haster
2024-02-09 00:06:58 -06:00
parent bd55822abc
commit 9f9653eb79
1 changed files with 21 additions and 40 deletions
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lfs.c
+21 -40
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@@ -1825,7 +1825,6 @@ static int lfsr_gdelta_xor(lfs_t *lfs,
return LFS_ERR_CORRUPT;
}
// TODO is there a way to avoid byte-level operations here?
// xor with data, this should at least be cached if on-disk
for (lfs_size_t i = 0; i < xor_size; i++) {
uint8_t x;
@@ -1865,35 +1864,6 @@ static inline bool lfsr_grm_isrm(const lfsr_grm_t *grm, lfsr_smid_t mid) {
return grm->rms[0] == mid || grm->rms[1] == mid;
}
static inline bool lfsr_grm_iszero(
const uint8_t gdelta[static LFSR_GRM_DSIZE]) {
return lfsr_gdelta_iszero(gdelta, LFSR_GRM_DSIZE);
}
static inline lfs_size_t lfsr_grm_size(
const uint8_t gdelta[static LFSR_GRM_DSIZE]) {
return lfsr_gdelta_size(gdelta, LFSR_GRM_DSIZE);
}
static inline int lfsr_grm_xor(lfs_t *lfs,
uint8_t gdelta[static LFSR_GRM_DSIZE],
lfsr_data_t xor) {
return lfsr_gdelta_xor(lfs, gdelta, LFSR_GRM_DSIZE, xor);
}
// needed by lfsr_grm_xorgrm
static lfsr_data_t lfsr_data_fromgrm(const lfsr_grm_t *grm,
uint8_t buffer[static LFSR_GRM_DSIZE]);
static inline void lfsr_grm_xorgrm(lfs_t *lfs,
uint8_t gdelta[static LFSR_GRM_DSIZE],
const lfsr_grm_t *grm) {
uint8_t buf[LFSR_GRM_DSIZE];
int err = lfsr_grm_xor(lfs, gdelta,
lfsr_data_fromgrm(grm, buf));
LFS_ASSERT(!err);
}
#define LFSR_DATA_FROMGRM(_grm, _buffer) \
lfsr_data_fromgrm(_grm, _buffer)
@@ -1915,7 +1885,18 @@ static lfsr_data_t lfsr_data_fromgrm(const lfsr_grm_t *grm,
d += d_;
}
return LFSR_DATA_BUF(buffer, lfsr_grm_size(buffer));
return LFSR_DATA_BUF(buffer, lfsr_gdelta_size(buffer, LFSR_GRM_DSIZE));
}
static inline void lfsr_gdelta_xorgrm(lfs_t *lfs,
uint8_t *gdelta, lfs_size_t size,
const lfsr_grm_t *grm) {
LFS_ASSERT(size >= LFSR_GRM_DSIZE);
uint8_t buf[LFSR_GRM_DSIZE];
int err = lfsr_gdelta_xor(lfs, gdelta, size,
lfsr_data_fromgrm(grm, buf));
LFS_ASSERT(!err);
}
// required by lfsr_data_readgrm
@@ -3581,7 +3562,7 @@ static int lfsr_rbyd_compact(lfs_t *lfs, lfsr_rbyd_t *rbyd_,
// append and consume any pending gstate
static int lfsr_rbyd_appendgdelta(lfs_t *lfs, lfsr_rbyd_t *rbyd) {
// need grm delta?
if (!lfsr_grm_iszero(lfs->grm_d)) {
if (!lfsr_gdelta_iszero(lfs->grm_d, LFSR_GRM_DSIZE)) {
uint8_t grm_[LFSR_GRM_DSIZE];
memcpy(grm_, lfs->grm_d, LFSR_GRM_DSIZE);
@@ -3593,14 +3574,14 @@ static int lfsr_rbyd_appendgdelta(lfs_t *lfs, lfsr_rbyd_t *rbyd) {
return err;
}
if (err != LFS_ERR_NOENT) {
err = lfsr_grm_xor(lfs, grm_, data);
err = lfsr_gdelta_xor(lfs, grm_, LFSR_GRM_DSIZE, data);
if (err) {
return err;
}
}
// append to our rbyd, replacing any existing delta
lfs_size_t size = lfsr_grm_size(grm_);
lfs_size_t size = lfsr_gdelta_size(grm_, LFSR_GRM_DSIZE);
err = lfsr_rbyd_appendattr(lfs, rbyd, -1,
// opportunistically remove this tag if delta is all zero
(size == 0) ? LFSR_TAG_RM(GRMDELTA) : LFSR_TAG_GRMDELTA, 0,
@@ -5434,7 +5415,7 @@ static int lfsr_fs_consumegdelta(lfs_t *lfs, const lfsr_mdir_t *mdir) {
}
if (err != LFS_ERR_NOENT) {
err = lfsr_grm_xor(lfs, lfs->grm_d, data);
err = lfsr_gdelta_xor(lfs, lfs->grm_d, LFSR_GRM_DSIZE, data);
if (err) {
return err;
}
@@ -6203,10 +6184,10 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
if (attrs[i].tag == LFSR_TAG_GRM) {
// encode to disk
lfsr_grm_t *grm = lfsr_attr_grm(&attrs[i]);
lfsr_grm_xorgrm(lfs, lfs->grm_d, grm);
lfsr_gdelta_xorgrm(lfs, lfs->grm_d, LFSR_GRM_DSIZE, grm);
// xor with our current gstate to find our initial gdelta
int err = lfsr_grm_xor(lfs, lfs->grm_d,
int err = lfsr_gdelta_xor(lfs, lfs->grm_d, LFSR_GRM_DSIZE,
LFSR_DATA_BUF(lfs->grm_g, LFSR_GRM_DSIZE));
if (err) {
return err;
@@ -6491,7 +6472,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
// gd' = gd xor (grm' xor grm)
//
lfsr_grm_t *grm = lfsr_attr_grm(&attrs[i]);
lfsr_grm_xorgrm(lfs, lfs->grm_d, grm);
lfsr_gdelta_xorgrm(lfs, lfs->grm_d, LFSR_GRM_DSIZE, grm);
// patch our grm
for (int j = 0; j < 2; j++) {
@@ -6508,7 +6489,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
}
// xor our patch into our gdelta
lfsr_grm_xorgrm(lfs, lfs->grm_d, grm);
lfsr_gdelta_xorgrm(lfs, lfs->grm_d, LFSR_GRM_DSIZE, grm);
}
}
@@ -6655,7 +6636,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
}
// gstate must have been committed by a lower-level function at this point
LFS_ASSERT(lfsr_grm_iszero(lfs->grm_d));
LFS_ASSERT(lfsr_gdelta_iszero(lfs->grm_d, LFSR_GRM_DSIZE));
// success? update in-device state, we must not error at this point