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mdbx: микро-оптимизация cursor_set().

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Леонид Юрьев (Leonid Yuriev) 2023-11-13 20:52:35 +03:00
parent 6cef39c32f
commit 7f21515940
1 changed files with 17 additions and 18 deletions
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35
src/core.c
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@ -16818,7 +16818,7 @@ cursor_set(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data, MDBX_cursor_op op) {
}
MDBX_val aligned_key = *key;
uint64_t aligned_keybytes;
uint64_t aligned_key_buf;
if (mc->mc_db->md_flags & MDBX_INTEGERKEY) {
switch (aligned_key.iov_len) {
default:
@ -16829,13 +16829,13 @@ cursor_set(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data, MDBX_cursor_op op) {
if (unlikely(3 & (uintptr_t)aligned_key.iov_base))
/* copy instead of return error to avoid break compatibility */
aligned_key.iov_base =
memcpy(&aligned_keybytes, aligned_key.iov_base, 4);
memcpy(&aligned_key_buf, aligned_key.iov_base, 4);
break;
case 8:
if (unlikely(7 & (uintptr_t)aligned_key.iov_base))
/* copy instead of return error to avoid break compatibility */
aligned_key.iov_base =
memcpy(&aligned_keybytes, aligned_key.iov_base, 8);
memcpy(&aligned_key_buf, aligned_key.iov_base, 8);
break;
}
}
@ -16874,7 +16874,7 @@ cursor_set(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data, MDBX_cursor_op op) {
}
if (cmp > 0) {
const size_t nkeys = page_numkeys(mp);
if (nkeys > 1) {
if (likely(nkeys > 1)) {
if (IS_LEAF2(mp)) {
nodekey.iov_base = page_leaf2key(mp, nkeys - 1, nodekey.iov_len);
} else {
@ -16918,23 +16918,22 @@ cursor_set(MDBX_cursor *mc, MDBX_val *key, MDBX_val *data, MDBX_cursor_op op) {
}
/* If any parents have right-sibs, search.
* Otherwise, there's nothing further. */
size_t i;
for (i = 0; i < mc->mc_top; i++)
for (size_t i = 0; i < mc->mc_top; i++)
if (mc->mc_ki[i] < page_numkeys(mc->mc_pg[i]) - 1)
break;
if (i == mc->mc_top) {
/* There are no other pages */
cASSERT(mc, nkeys <= UINT16_MAX);
mc->mc_ki[mc->mc_top] = (uint16_t)nkeys;
mc->mc_flags |= C_EOF;
ret.err = MDBX_NOTFOUND;
return ret;
}
goto continue_other_pages;
/* There are no other pages */
cASSERT(mc, nkeys <= UINT16_MAX);
mc->mc_ki[mc->mc_top] = (uint16_t)nkeys;
mc->mc_flags |= C_EOF;
ret.err = MDBX_NOTFOUND;
return ret;
}
continue_other_pages:
if (!mc->mc_top) {
/* There are no other pages */
mc->mc_ki[mc->mc_top] = 0;
if (op == MDBX_SET_RANGE)
if (op >= MDBX_SET_RANGE)
goto got_node;
cASSERT(mc, mc->mc_ki[mc->mc_top] < page_numkeys(mc->mc_pg[mc->mc_top]) ||
@ -16996,7 +16995,7 @@ got_node:
}
if (IS_LEAF2(mp)) {
if (op == MDBX_SET_RANGE || op == MDBX_SET_KEY) {
if (op >= MDBX_SET_KEY) {
key->iov_len = mc->mc_db->md_xsize;
key->iov_base = page_leaf2key(mp, mc->mc_ki[mc->mc_top], key->iov_len);
}
@ -17076,7 +17075,7 @@ got_node:
}
/* The key already matches in all other cases */
if (op == MDBX_SET_RANGE || op == MDBX_SET_KEY)
if (op >= MDBX_SET_KEY)
get_key_optional(node, key);
DEBUG("==> cursor placed on key [%s], data [%s]", DKEY_DEBUG(key),