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Dropped LFSR_DATA_* macros with implicit buffers

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This was a disappointing failure of compount-literals.

These macros protect against mismatched buffer sizes, which is great for
preventing bugs caused by simple typos, but the overhead of compound-
literals requiring initialization make them simply unusable.

This commit leaves only a couple macros with implicit buffers:
LFSR_DATA_LEB128, and the LFSR_RAT_CAT/LFSR_RATS macros.

Even the tiny cleanup of the one remaining implicit-buffer macro still
in use, LFSR_DATA_GEOMETRY, saved some code:

           code          stack          ctx
  before: 38084           2608          752
  after:  38060 (-0.1%)   2608 (+0.0%)  752 (+0.0%)
This commit is contained in:
Christopher Haster
2025-01-05 00:54:07 -06:00
parent 1746819c7c
commit 80f4e0b825
3 changed files with 62 additions and 71 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lfs.c
+46 -64
View File
@@ -2341,12 +2341,9 @@ typedef struct lfsr_ecksum {
//
#define LFSR_ECKSUM_DSIZE (4+4)
#define LFSR_DATA_ECKSUM_(_ecksum, _buffer) \
#define LFSR_DATA_ECKSUM(_ecksum, _buffer) \
((struct {lfsr_data_t d;}){lfsr_data_fromecksum(_ecksum, _buffer)}.d)
#define LFSR_DATA_ECKSUM(_ecksum) \
LFSR_DATA_ECKSUM_(_ecksum, (uint8_t[LFSR_ECKSUM_DSIZE]){0})
static lfsr_data_t lfsr_data_fromecksum(const lfsr_ecksum_t *ecksum,
uint8_t buffer[static LFSR_ECKSUM_DSIZE]) {
// you shouldn't try to encode a not-ecksum, that doesn't make sense
@@ -2400,12 +2397,9 @@ static int lfsr_data_readecksum(lfs_t *lfs, lfsr_data_t *data,
//
#define LFSR_BPTR_DSIZE (4+5+4+4+4)
#define LFSR_DATA_BPTR_(_bptr, _buffer) \
#define LFSR_DATA_BPTR(_bptr, _buffer) \
((struct {lfsr_data_t d;}){lfsr_data_frombptr(_bptr, _buffer)}.d)
#define LFSR_DATA_BPTR(_bptr) \
LFSR_DATA_BPTR_(_bptr, (uint8_t[LFSR_BPTR_DSIZE]){0})
// checked reads adds ck info to lfsr_data_t that we don't want to
// unnecessarily duplicate, this makes accessing ck info annoyingly
// messy...
@@ -4024,7 +4018,7 @@ static int lfsr_rbyd_appendcksum(lfs_t *lfs, lfsr_rbyd_t *rbyd) {
uint8_t ecksum_buf[LFSR_ECKSUM_DSIZE];
err = lfsr_rbyd_appendrat_(lfs, rbyd, LFSR_RAT(
LFSR_TAG_ECKSUM, 0, LFSR_DATA_ECKSUM_(
LFSR_TAG_ECKSUM, 0, LFSR_DATA_ECKSUM(
(&(lfsr_ecksum_t){
.cksize=lfs->cfg->prog_size,
.cksum=ecksum}),
@@ -4612,12 +4606,9 @@ static inline int lfsr_btree_cmp(
//
#define LFSR_BRANCH_DSIZE (5+4+4)
#define LFSR_DATA_BRANCH_(_branch, _buffer) \
#define LFSR_DATA_BRANCH(_branch, _buffer) \
((struct {lfsr_data_t d;}){lfsr_data_frombranch(_branch, _buffer)}.d)
#define LFSR_DATA_BRANCH(_branch) \
LFSR_DATA_BRANCH_(_branch, (uint8_t[LFSR_BRANCH_DSIZE]){0})
static lfsr_data_t lfsr_data_frombranch(const lfsr_rbyd_t *branch,
uint8_t buffer[static LFSR_BRANCH_DSIZE]) {
// block should not exceed 31-bits
@@ -4735,12 +4726,9 @@ static int lfsr_data_fetchbranch(lfs_t *lfs,
//
#define LFSR_BTREE_DSIZE (5+LFSR_BRANCH_DSIZE)
#define LFSR_DATA_BTREE_(_btree, _buffer) \
#define LFSR_DATA_BTREE(_btree, _buffer) \
((struct {lfsr_data_t d;}){lfsr_data_frombtree(_btree, _buffer)}.d)
#define LFSR_DATA_BTREE(_btree) \
LFSR_DATA_BTREE_(_btree, (uint8_t[LFSR_BTREE_DSIZE]){0})
static lfsr_data_t lfsr_data_frombtree(const lfsr_btree_t *btree,
uint8_t buffer[static LFSR_BTREE_DSIZE]) {
// weight should not exceed 31-bits
@@ -5361,12 +5349,12 @@ static int lfsr_btree_commit__(lfs_t *lfs, lfsr_btree_t *btree,
if (!lfsr_rbyd_trunk(&parent)) {
bscratch->rats[rat_count_++] = LFSR_RAT(
LFSR_TAG_BRANCH, +rbyd__.weight,
LFSR_DATA_BRANCH_(
LFSR_DATA_BRANCH(
&rbyd__,
&bscratch->buf[0*LFSR_BRANCH_DSIZE]));
bscratch->rats[rat_count_++] = LFSR_RAT(
LFSR_TAG_BRANCH, +sibling.weight,
LFSR_DATA_BRANCH_(
LFSR_DATA_BRANCH(
&sibling,
&bscratch->buf[1*LFSR_BRANCH_DSIZE]));
if (lfsr_tag_suptype(split_tag) == LFSR_TAG_NAME) {
@@ -5379,7 +5367,7 @@ static int lfsr_btree_commit__(lfs_t *lfs, lfsr_btree_t *btree,
bid_ -= pid - (rbyd_.weight-1);
bscratch->rats[rat_count_++] = LFSR_RAT(
LFSR_TAG_BRANCH, 0,
LFSR_DATA_BRANCH_(
LFSR_DATA_BRANCH(
&rbyd__,
&bscratch->buf[0*LFSR_BRANCH_DSIZE]));
if (rbyd__.weight != rbyd_.weight) {
@@ -5389,7 +5377,7 @@ static int lfsr_btree_commit__(lfs_t *lfs, lfsr_btree_t *btree,
}
bscratch->rats[rat_count_++] = LFSR_RAT(
LFSR_TAG_BRANCH, +sibling.weight,
LFSR_DATA_BRANCH_(
LFSR_DATA_BRANCH(
&sibling,
&bscratch->buf[1*LFSR_BRANCH_DSIZE]));
if (lfsr_tag_suptype(split_tag) == LFSR_TAG_NAME) {
@@ -5474,7 +5462,7 @@ static int lfsr_btree_commit__(lfs_t *lfs, lfsr_btree_t *btree,
LFSR_TAG_RM, -sibling.weight, LFSR_DATA_NULL());
bscratch->rats[rat_count_++] = LFSR_RAT(
LFSR_TAG_BRANCH, 0,
LFSR_DATA_BRANCH_(&rbyd__, bscratch->buf));
LFSR_DATA_BRANCH(&rbyd__, bscratch->buf));
if (rbyd__.weight != rbyd_.weight) {
bscratch->rats[rat_count_++] = LFSR_RAT(
LFSR_TAG_GROW, -rbyd_.weight + rbyd__.weight,
@@ -5514,7 +5502,7 @@ static int lfsr_btree_commit__(lfs_t *lfs, lfsr_btree_t *btree,
} else {
bscratch->rats[rat_count_++] = LFSR_RAT(
LFSR_TAG_BRANCH, 0,
LFSR_DATA_BRANCH_(&rbyd__, bscratch->buf));
LFSR_DATA_BRANCH(&rbyd__, bscratch->buf));
if (rbyd__.weight != rbyd_.weight) {
bscratch->rats[rat_count_++] = LFSR_RAT(
LFSR_TAG_GROW, -rbyd_.weight + rbyd__.weight,
@@ -5927,12 +5915,9 @@ static inline int lfsr_shrub_cmp(
//
#define LFSR_SHRUB_DSIZE (5+4)
#define LFSR_DATA_SHRUB_(_rbyd, _buffer) \
#define LFSR_DATA_SHRUB(_rbyd, _buffer) \
((struct {lfsr_data_t d;}){lfsr_data_fromshrub(_rbyd, _buffer)}.d)
#define LFSR_DATA_SHRUB(_rbyd) \
LFSR_DATA_SHRUB_(_rbyd, (uint8_t[LFSR_SHRUB_DSIZE]){0})
static lfsr_data_t lfsr_data_fromshrub(const lfsr_shrub_t *shrub,
uint8_t buffer[static LFSR_SHRUB_DSIZE]) {
// shrub trunks should never be null
@@ -6522,12 +6507,9 @@ static inline bool lfsr_mptr_ismrootanchor(
//
#define LFSR_MPTR_DSIZE (5+5)
#define LFSR_DATA_MPTR_(_mptr, _buffer) \
#define LFSR_DATA_MPTR(_mptr, _buffer) \
((struct {lfsr_data_t d;}){lfsr_data_frommptr(_mptr, _buffer)}.d)
#define LFSR_DATA_MPTR(_mptr) \
LFSR_DATA_MPTR_(_mptr, (uint8_t[LFSR_MPTR_DSIZE]){0})
static lfsr_data_t lfsr_data_frommptr(const lfs_block_t mptr[static 2],
uint8_t buffer[static LFSR_MPTR_DSIZE]) {
// blocks should not exceed 31-bits
@@ -6895,12 +6877,9 @@ static inline bool lfsr_grm_ismidrm(const lfs_t *lfs, lfsr_smid_t mid) {
return lfs->grm.mids[0] == mid || lfs->grm.mids[1] == mid;
}
#define LFSR_DATA_GRM_(_grm, _buffer) \
#define LFSR_DATA_GRM(_grm, _buffer) \
((struct {lfsr_data_t d;}){lfsr_data_fromgrm(_grm, _buffer)}.d)
#define LFSR_DATA_GRM(_grm) \
LFSR_DATA_GRM_(_grm, (uint8_t[LFSR_GRM_DSIZE]){0})
static lfsr_data_t lfsr_data_fromgrm(const lfsr_grm_t *grm,
uint8_t buffer[static LFSR_GRM_DSIZE]) {
// make sure to zero so we don't leak any info
@@ -7534,7 +7513,7 @@ static int lfsr_mdir_commit__(lfs_t *lfs, lfsr_mdir_t *mdir,
lfsr_tag_mode(rats[i].tag) | LFSR_TAG_BSHRUB,
rats[i].weight,
// note we use the staged trunk here
LFSR_DATA_SHRUB_(shrub_, shrub_buf)));
LFSR_DATA_SHRUB(shrub_, shrub_buf)));
if (err) {
return err;
}
@@ -7599,7 +7578,7 @@ static int lfsr_mdir_commit__(lfs_t *lfs, lfsr_mdir_t *mdir,
rid - lfs_smax(start_rid, 0),
LFSR_RAT(
LFSR_TAG_BSHRUB, 0,
LFSR_DATA_SHRUB_(&shrub, shrub_buf)));
LFSR_DATA_SHRUB(&shrub, shrub_buf)));
if (err) {
return err;
}
@@ -7978,7 +7957,7 @@ static int lfsr_mdir_compact__(lfs_t *lfs, lfsr_mdir_t *mdir_,
err = lfsr_rbyd_appendcompactrat(lfs, &mdir_->rbyd,
LFSR_RAT(
tag, weight,
LFSR_DATA_SHRUB_(&shrub, shrub_buf)));
LFSR_DATA_SHRUB(&shrub, shrub_buf)));
if (err) {
LFS_ASSERT(err != LFS_ERR_RANGE);
return err;
@@ -8427,7 +8406,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
0, LFSR_RATS(
LFSR_RAT(
LFSR_TAG_MDIR, +(1 << lfs->mdir_bits),
LFSR_DATA_MPTR_(
LFSR_DATA_MPTR(
mdir_[0].rbyd.blocks,
&mdir_buf[0*LFSR_MPTR_DSIZE])),
LFSR_RAT_CAT_(
@@ -8435,7 +8414,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
&split_data, 1),
LFSR_RAT(
LFSR_TAG_MDIR, 0,
LFSR_DATA_MPTR_(
LFSR_DATA_MPTR(
mdir_[1].rbyd.blocks,
&mdir_buf[1*LFSR_MPTR_DSIZE]))));
if (err) {
@@ -8452,7 +8431,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
lfsr_mid_bid(lfs, mdir->mid), LFSR_RATS(
LFSR_RAT(
LFSR_TAG_MDIR, 0,
LFSR_DATA_MPTR_(
LFSR_DATA_MPTR(
mdir_[0].rbyd.blocks,
&mdir_buf[0*LFSR_MPTR_DSIZE])),
LFSR_RAT_CAT_(
@@ -8460,7 +8439,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
&split_data, 1),
LFSR_RAT(
LFSR_TAG_MDIR, 0,
LFSR_DATA_MPTR_(
LFSR_DATA_MPTR(
mdir_[1].rbyd.blocks,
&mdir_buf[1*LFSR_MPTR_DSIZE]))));
if (err) {
@@ -8530,7 +8509,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
lfsr_mid_bid(lfs, mdir->mid), LFSR_RATS(
LFSR_RAT(
LFSR_TAG_MDIR, 0,
LFSR_DATA_MPTR_(
LFSR_DATA_MPTR(
mdir_[0].rbyd.blocks,
mdir_buf))));
if (err) {
@@ -8601,10 +8580,10 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
(lfsr_mtree_ismptr(&mtree_))
? LFSR_RAT(
LFSR_TAG_SUB | LFSR_TAG_MDIR, 0,
LFSR_DATA_MPTR_(mtree_.u.mptr.blocks, mtree_buf))
LFSR_DATA_MPTR(mtree_.u.mptr.blocks, mtree_buf))
: LFSR_RAT(
LFSR_TAG_SUB | LFSR_TAG_MTREE, 0,
LFSR_DATA_BTREE_(&mtree_.u.btree, mtree_buf)),
LFSR_DATA_BTREE(&mtree_.u.btree, mtree_buf)),
// were we committing to the mroot? include any -1 rats
(mdir->mid == -1)
? LFSR_RAT_RATS(
@@ -8653,7 +8632,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
-1, LFSR_RATS(
LFSR_RAT(
LFSR_TAG_MROOT, 0,
LFSR_DATA_MPTR_(
LFSR_DATA_MPTR(
mrootchild_.rbyd.blocks,
mrootchild_buf))));
if (err) {
@@ -8705,7 +8684,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
LFSR_DATA_BUF("littlefs", 8)),
LFSR_RAT(
LFSR_TAG_MROOT, 0,
LFSR_DATA_MPTR_(
LFSR_DATA_MPTR(
mrootchild_.rbyd.blocks,
mrootchild_buf))));
if (err) {
@@ -11456,7 +11435,7 @@ static int lfsr_file_carve(lfs_t *lfs, lfsr_file_t *file,
} else if (lfsr_bshrub_isbptr(&file->o.o.mdir, &file->o.bshrub)) {
rats[rat_count++] = LFSR_RAT(
LFSR_TAG_BLOCK, +lfsr_bshrub_size(&file->o.bshrub),
LFSR_DATA_BPTR_(&file->o.bshrub.u.bptr, left.buf));
LFSR_DATA_BPTR(&file->o.bshrub.u.bptr, left.buf));
}
file->o.bshrub.u.bshrub = LFSR_SHRUB_NULL(
@@ -11543,7 +11522,7 @@ static int lfsr_file_carve(lfs_t *lfs, lfsr_file_t *file,
LFSR_RAT(
LFSR_TAG_BLOCK,
+(weight_ - lfs->cfg->fragment_size),
LFSR_DATA_BPTR_(&bptr_, left.buf))));
LFSR_DATA_BPTR(&bptr_, left.buf))));
if (err) {
return err;
}
@@ -11567,7 +11546,7 @@ static int lfsr_file_carve(lfs_t *lfs, lfsr_file_t *file,
LFSR_RAT(
LFSR_TAG_GROW | LFSR_TAG_SUB | LFSR_TAG_BLOCK,
-(weight_ - lfsr_data_size(bptr_.data)),
LFSR_DATA_BPTR_(&bptr_, right.buf)),
LFSR_DATA_BPTR(&bptr_, right.buf)),
LFSR_RAT_CAT(
LFSR_TAG_DATA,
+(weight_ - lfsr_data_size(bptr_.data)),
@@ -11604,7 +11583,7 @@ static int lfsr_file_carve(lfs_t *lfs, lfsr_file_t *file,
rats[rat_count++] = LFSR_RAT(
LFSR_TAG_GROW | LFSR_TAG_SUB | LFSR_TAG_BLOCK,
-(bid+1 - pos),
LFSR_DATA_BPTR_(
LFSR_DATA_BPTR(
LFS_IFDEF_CKDATACKSUMS(
(&(lfsr_bptr_t){
.data=left_slice_}),
@@ -11661,7 +11640,7 @@ static int lfsr_file_carve(lfs_t *lfs, lfsr_file_t *file,
right_rat_ = LFSR_RAT(
tag_,
bid+1 - (pos+weight),
LFSR_DATA_BPTR_(
LFSR_DATA_BPTR(
LFS_IFDEF_CKDATACKSUMS(
(&(lfsr_bptr_t){
.data=right_slice_}),
@@ -12100,7 +12079,7 @@ static int lfsr_file_flush_(lfs_t *lfs, lfsr_file_t *file,
block_start, block_end - block_start,
LFSR_RAT(
LFSR_TAG_BLOCK, 0,
LFSR_DATA_BPTR_(&bptr, bptr_buf)));
LFSR_DATA_BPTR(&bptr, bptr_buf)));
if (err) {
return err;
}
@@ -12553,7 +12532,7 @@ int lfsr_file_sync(lfs_t *lfs, lfsr_file_t *file) {
} else if (lfsr_bshrub_isbtree(&file->o.o.mdir, &file->o.bshrub)) {
rats[rat_count++] = LFSR_RAT(
LFSR_TAG_SUB | LFSR_TAG_BTREE, 0,
LFSR_DATA_BTREE_(&file->o.bshrub.u.btree, buf));
LFSR_DATA_BTREE(&file->o.bshrub.u.btree, buf));
} else {
LFS_UNREACHABLE();
}
@@ -13525,12 +13504,9 @@ typedef struct lfsr_geometry {
// '---+- -+- -+- -+- -'
#define LFSR_GEOMETRY_DSIZE (4+5)
#define LFSR_DATA_GEOMETRY_(_geometry, _buffer) \
#define LFSR_DATA_GEOMETRY(_geometry, _buffer) \
((struct {lfsr_data_t d;}){lfsr_data_fromgeometry(_geometry, _buffer)}.d)
#define LFSR_DATA_GEOMETRY(_geometry) \
LFSR_DATA_GEOMETRY_(_geometry, (uint8_t[LFSR_GEOMETRY_DSIZE]){0})
static lfsr_data_t lfsr_data_fromgeometry(const lfsr_geometry_t *geometry,
uint8_t buffer[static LFSR_GEOMETRY_DSIZE]) {
lfs_ssize_t d = 0;
@@ -14019,6 +13995,7 @@ static int lfsr_formatinited(lfs_t *lfs) {
// - our magic string, "littlefs"
// - any format-time configuration
// - the root's bookmark tag, which reserves did = 0 for the root
uint8_t geometry_buf[LFSR_GEOMETRY_DSIZE];
err = lfsr_rbyd_commit(lfs, &rbyd, -1, LFSR_RATS(
LFSR_RAT(
LFSR_TAG_MAGIC, 0,
@@ -14033,9 +14010,11 @@ static int lfsr_formatinited(lfs_t *lfs) {
LFSR_DATA_RCOMPAT(LFSR_RCOMPAT_COMPAT)),
LFSR_RAT(
LFSR_TAG_GEOMETRY, 0,
LFSR_DATA_GEOMETRY((&(lfsr_geometry_t){
lfs->cfg->block_size,
lfs->cfg->block_count}))),
LFSR_DATA_GEOMETRY(
(&(lfsr_geometry_t){
lfs->cfg->block_size,
lfs->cfg->block_count}),
geometry_buf)),
LFSR_RAT(
LFSR_TAG_NAMELIMIT, 0,
LFSR_DATA_LLEB128(lfs->name_limit)),
@@ -14523,12 +14502,15 @@ int lfsr_fs_grow(lfs_t *lfs, lfs_size_t block_count_) {
// update our on-disk config
lfs_alloc_ckpoint(lfs);
uint8_t geometry_buf[LFSR_GEOMETRY_DSIZE];
int err = lfsr_mdir_commit(lfs, &lfs->mroot, LFSR_RATS(
LFSR_RAT(
LFSR_TAG_GEOMETRY, 0,
LFSR_DATA_GEOMETRY((&(lfsr_geometry_t){
lfs->cfg->block_size,
block_count_})))));
LFSR_DATA_GEOMETRY(
(&(lfsr_geometry_t){
lfs->cfg->block_size,
block_count_}),
geometry_buf))));
if (err) {
goto failed;
}
tests/test_mount.toml
+12 -6
View File
@@ -908,12 +908,15 @@ code = '''
// note we're messing around with internals to do this! this
// is not a user API
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
uint8_t geometry_buf[LFSR_GEOMETRY_DSIZE];
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_RATS(
LFSR_RAT(
LFSR_TAG_GEOMETRY, 0,
LFSR_DATA_GEOMETRY((&(lfsr_geometry_t){
INC_BLOCK_SIZE,
BLOCK_COUNT}))))) => 0;
LFSR_DATA_GEOMETRY(
(&(lfsr_geometry_t){
INC_BLOCK_SIZE,
BLOCK_COUNT}),
geometry_buf)))) => 0;
lfsr_unmount(&lfs) => 0;
// mount should now fail
@@ -935,12 +938,15 @@ code = '''
// note we're messing around with internals to do this! this
// is not a user API
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
uint8_t geometry_buf[LFSR_GEOMETRY_DSIZE];
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_RATS(
LFSR_RAT(
LFSR_TAG_GEOMETRY, 0,
LFSR_DATA_GEOMETRY((&(lfsr_geometry_t){
BLOCK_SIZE,
INC_BLOCK_COUNT}))))) => 0;
LFSR_DATA_GEOMETRY(
(&(lfsr_geometry_t){
BLOCK_SIZE,
INC_BLOCK_COUNT}),
geometry_buf)))) => 0;
lfsr_unmount(&lfs) => 0;
// mount should now fail
tests/test_mtree.toml
+4 -1
View File
@@ -4323,10 +4323,13 @@ code = '''
lfsr_mount(&lfs, LFS_M_RDWR, CFG) => 0;
lfs_alloc_ckpoint(&lfs);
uint8_t mptr_buf[LFSR_MPTR_DSIZE];
lfsr_mdir_commit(&lfs, &lfs.mroot, LFSR_RATS(
LFSR_RAT(
LFSR_TAG_MROOT, 0,
LFSR_DATA_MPTR(LFSR_MPTR_MROOTANCHOR())))) => 0;
LFSR_DATA_MPTR(
LFSR_MPTR_MROOTANCHOR(),
mptr_buf)))) => 0;
// technically, cycle detection only needs to work when we're validating
lfsr_traversal_t t = LFSR_TRAVERSAL(