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Adopted compiler friendly generalized lfs3_file_crystallize_ API

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Seeing as the generalized lfs3_file_crystallize_ API had a much lower
cost than I thought, we might as well keep it around a bit longer.

Though I at least tweaked it to hopefully be easier for compilers to
optimize: By accepting crystal_min=-1 as an alias for
crystal_min=crystal_max, compilers should always by able to const
propagate this.

---

Note sure why this still adds 8 bytes of code, it just looks like
compiler noise in lfs3_file_crystallize__? Is the LFS3_NOINLINE
attribute messing with compiler optimizations?

           code          stack          ctx
  before: 37580           2472          656
  after:  37588 (+0.0%)   2472 (+0.0%)  656 (+0.0%)
This commit is contained in:
Christopher Haster
2025-07-03 18:24:48 -05:00
parent d6f332fa9f
commit e443af800b
1 changed files with 30 additions and 9 deletions
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lfs3.c
+30 -9
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@@ -12498,18 +12498,27 @@ failed:;
}
#endif
// note the slightly unique behavior when crystal_min=-1:
// - crystal_min=-1 => crystal_min=crystal_max
// - crystal_max=-1 => crystal_max=unbounded
//
// this helps avoid duplicate arguments with tight crystal bounds, if
// you really want to crystallize as little as possible, use
// crystal_min=0
//
#if !defined(LFS3_RDONLY) && !defined(LFS3_KVONLY) && !defined(LFS3_2BONLY)
// this LFS3_NOINLINE is to force lfs3_file_crystallize__ off the stack
// hot-path
LFS3_NOINLINE
static int lfs3_file_crystallize__(lfs3_t *lfs3, lfs3_file_t *file,
lfs3_off_t block_pos, lfs3_ssize_t crystal_size,
lfs3_off_t block_pos,
lfs3_ssize_t crystal_min, lfs3_ssize_t crystal_max,
lfs3_off_t pos, const uint8_t *buffer, lfs3_size_t size) {
// align to prog_size, limit to block_size and theoretical file size
lfs3_off_t crystal_limit = lfs3_min(
block_pos + lfs3_min(
lfs3_aligndown(
(lfs3_off_t)crystal_size,
(lfs3_off_t)crystal_max,
lfs3->cfg->prog_size),
lfs3->cfg->block_size),
lfs3_max(
@@ -12607,7 +12616,10 @@ static int lfs3_file_crystallize__(lfs3_t *lfs3, lfs3_file_t *file,
// but make sure to include all of the requested
// crystal if explicit, otherwise above loops
// may never terminate
&& (lfs3_soff_t)(pos_ - block_pos) >= crystal_size) {
&& (lfs3_soff_t)(pos_ - block_pos)
>= (lfs3_soff_t)lfs3_min(
crystal_min,
crystal_max)) {
// if we hit this condition, mark as crystallized,
// attempting resume crystallization will not make
// progress
@@ -12736,15 +12748,24 @@ static int lfs3_file_crystallize__(lfs3_t *lfs3, lfs3_file_t *file,
}
#endif
// note the slightly unique behavior when crystal_min=-1:
// - crystal_min=-1 => crystal_min=crystal_max
// - crystal_max=-1 => crystal_max=unbounded
//
// this helps avoid duplicate arguments with tight crystal bounds, if
// you really want to crystallize as little as possible, use
// crystal_min=0
//
#if !defined(LFS3_RDONLY) && !defined(LFS3_KVONLY) && !defined(LFS3_2BONLY)
static int lfs3_file_crystallize_(lfs3_t *lfs3, lfs3_file_t *file,
lfs3_off_t block_pos, lfs3_ssize_t crystal_size,
lfs3_off_t block_pos,
lfs3_ssize_t crystal_min, lfs3_ssize_t crystal_max,
lfs3_off_t pos, const uint8_t *buffer, lfs3_size_t size) {
// this is split into two functions to try to minimize stack usage
// crystallize
int err = lfs3_file_crystallize__(lfs3, file,
block_pos, crystal_size,
block_pos, crystal_min, crystal_max,
pos, buffer, size);
if (err) {
goto failed;
@@ -12789,7 +12810,7 @@ static int lfs3_file_crystallize(lfs3_t *lfs3, lfs3_file_t *file) {
lfs3_alloc_ckpoint(lfs3);
// finish crystallizing
int err = lfs3_file_crystallize_(lfs3, file,
file->leaf.pos - lfs3_bptr_off(&file->leaf.bptr), -1,
file->leaf.pos - lfs3_bptr_off(&file->leaf.bptr), -1, -1,
file->cache.pos, file->cache.buffer, file->cache.size);
if (err) {
return err;
@@ -12939,7 +12960,7 @@ static int lfs3_file_flush_(lfs3_t *lfs3, lfs3_file_t *file,
file->b.o.flags |= LFS3_o_UNCRYST;
// crystallize
int err = lfs3_file_crystallize_(lfs3, file,
block_start, (pos + size) - block_start,
block_start, -1, (pos + size) - block_start,
pos, buffer, size);
if (err) {
return err;
@@ -13068,7 +13089,7 @@ static int lfs3_file_flush_(lfs3_t *lfs3, lfs3_file_t *file,
file->b.o.flags |= LFS3_o_UNCRYST;
// crystallize
int err = lfs3_file_crystallize_(lfs3, file,
block_start, crystal_end - block_start,
block_start, -1, crystal_end - block_start,
pos, buffer, size);
if (err) {
return err;
@@ -13133,7 +13154,7 @@ static int lfs3_file_flush_(lfs3_t *lfs3, lfs3_file_t *file,
//
// lfs3_file_crystallize_ handles block allocation/relocation
err = lfs3_file_crystallize_(lfs3, file,
crystal_start, crystal_end - crystal_start,
crystal_start, -1, crystal_end - crystal_start,
pos, buffer, size);
if (err) {
return err;