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Prefer int for iterators where int size _really_ doesn't matter

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In theory int should always be the fastest type for simple loops.

No idea why this cost 4-bytes. Looking at the dissassembly, the int
version seems to write to the stack more often? The revision count
logic doesn't change at all... Compiler noise?

           code          stack
  before: 33438           2640
  after:  33442 (+0.0%)   2640 (+0.0%)
This commit is contained in:
Christopher Haster
2024-05-24 00:42:41 -05:00
parent 99e5fb87e0
commit dd007245a7
1 changed files with 3 additions and 3 deletions
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lfs.c
+3 -3
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@@ -6619,7 +6619,7 @@ static int lfsr_mdir_commit(lfs_t *lfs, lfsr_mdir_t *mdir,
// adjust pending grms? // adjust pending grms?
} else { } else {
for (lfs_size_t j = 0; j < 2; j++) { for (int j = 0; j < 2; j++) {
if (lfsr_mid_bid(lfs, lfs->grm.mids[j]) if (lfsr_mid_bid(lfs, lfs->grm.mids[j])
== lfsr_mid_bid(lfs, mid_) == lfsr_mid_bid(lfs, mid_)
&& lfs->grm.mids[j] >= mid_) { && lfs->grm.mids[j] >= mid_) {
@@ -8449,7 +8449,7 @@ static int lfsr_mountinited(lfs_t *lfs) {
} }
static int lfsr_formatinited(lfs_t *lfs) { static int lfsr_formatinited(lfs_t *lfs) {
for (lfs_size_t i = 0; i < 2; i++) { for (int i = 0; i < 2; i++) {
// write superblock to both rbyds in the root mroot to hopefully // write superblock to both rbyds in the root mroot to hopefully
// avoid mounting an older filesystem on disk // avoid mounting an older filesystem on disk
lfsr_rbyd_t rbyd = {.blocks[0]=i, .eoff=0, .trunk=0}; lfsr_rbyd_t rbyd = {.blocks[0]=i, .eoff=0, .trunk=0};
@@ -8463,7 +8463,7 @@ static int lfsr_formatinited(lfs_t *lfs) {
// something here to tell the initial mroot apart from btree nodes // something here to tell the initial mroot apart from btree nodes
// (rev=0), it's also useful for start with -1 and 0 in the upper // (rev=0), it's also useful for start with -1 and 0 in the upper
// bits to help test overflow/sequence comparison // bits to help test overflow/sequence comparison
uint32_t rev = ((i-1) << 28) uint32_t rev = (((uint32_t)i-1) << 28)
| (((1 << (28-lfs_smax32(lfs->recycle_bits, 0)))-1) | (((1 << (28-lfs_smax32(lfs->recycle_bits, 0)))-1)
& 0x00216968); & 0x00216968);
err = lfsr_rbyd_appendrev(lfs, &rbyd, rev); err = lfsr_rbyd_appendrev(lfs, &rbyd, rev);