Reduce nesting in phn_merge_siblings using an early return.

This commit is contained in:
Amaury Séchet 2023-10-25 00:36:08 +00:00 committed by Qi Wang
parent 10d713151d
commit 92aa52c062

View file

@ -162,6 +162,10 @@ phn_merge_siblings(void *phn, size_t offset, ph_cmp_t cmp) {
void *phn0 = phn;
void *phn1 = phn_next_get(phn0, offset);
if (phn1 == NULL) {
return phn0;
}
/*
* Multipass merge, wherein the first two elements of a FIFO
* are repeatedly merged, and each result is appended to the
@ -170,62 +174,61 @@ phn_merge_siblings(void *phn, size_t offset, ph_cmp_t cmp) {
* its tail, so we do a single pass over the sibling list to
* populate the FIFO.
*/
if (phn1 != NULL) {
void *phnrest = phn_next_get(phn1, offset);
if (phnrest != NULL) {
phn_prev_set(phnrest, NULL, offset);
}
phn_prev_set(phn0, NULL, offset);
phn_next_set(phn0, NULL, offset);
phn_prev_set(phn1, NULL, offset);
phn_next_set(phn1, NULL, offset);
phn0 = phn_merge(phn0, phn1, offset, cmp);
head = tail = phn0;
phn0 = phnrest;
while (phn0 != NULL) {
phn1 = phn_next_get(phn0, offset);
if (phn1 != NULL) {
phnrest = phn_next_get(phn1, offset);
if (phnrest != NULL) {
phn_prev_set(phnrest, NULL, offset);
}
phn_prev_set(phn0, NULL, offset);
phn_next_set(phn0, NULL, offset);
phn_prev_set(phn1, NULL, offset);
phn_next_set(phn1, NULL, offset);
phn0 = phn_merge(phn0, phn1, offset, cmp);
/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
phn_next_set(tail, phn0, offset);
tail = phn0;
phn0 = phnrest;
} else {
/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
phn_next_set(tail, phn0, offset);
tail = phn0;
phn0 = NULL;
}
}
phn0 = head;
void *phnrest = phn_next_get(phn1, offset);
if (phnrest != NULL) {
phn_prev_set(phnrest, NULL, offset);
}
phn_prev_set(phn0, NULL, offset);
phn_next_set(phn0, NULL, offset);
phn_prev_set(phn1, NULL, offset);
phn_next_set(phn1, NULL, offset);
phn0 = phn_merge(phn0, phn1, offset, cmp);
head = tail = phn0;
phn0 = phnrest;
while (phn0 != NULL) {
phn1 = phn_next_get(phn0, offset);
if (phn1 != NULL) {
while (true) {
head = phn_next_get(phn1, offset);
assert(phn_prev_get(phn0, offset) == NULL);
phn_next_set(phn0, NULL, offset);
assert(phn_prev_get(phn1, offset) == NULL);
phn_next_set(phn1, NULL, offset);
phn0 = phn_merge(phn0, phn1, offset, cmp);
if (head == NULL) {
break;
}
/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
phn_next_set(tail, phn0, offset);
tail = phn0;
phn0 = head;
phn1 = phn_next_get(phn0, offset);
phnrest = phn_next_get(phn1, offset);
if (phnrest != NULL) {
phn_prev_set(phnrest, NULL, offset);
}
phn_prev_set(phn0, NULL, offset);
phn_next_set(phn0, NULL, offset);
phn_prev_set(phn1, NULL, offset);
phn_next_set(phn1, NULL, offset);
phn0 = phn_merge(phn0, phn1, offset, cmp);
/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
phn_next_set(tail, phn0, offset);
tail = phn0;
phn0 = phnrest;
} else {
/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
phn_next_set(tail, phn0, offset);
tail = phn0;
phn0 = NULL;
}
}
phn0 = head;
phn1 = phn_next_get(phn0, offset);
if (phn1 != NULL) {
while (true) {
head = phn_next_get(phn1, offset);
assert(phn_prev_get(phn0, offset) == NULL);
phn_next_set(phn0, NULL, offset);
assert(phn_prev_get(phn1, offset) == NULL);
phn_next_set(phn1, NULL, offset);
phn0 = phn_merge(phn0, phn1, offset, cmp);
if (head == NULL) {
break;
}
/* NOLINTNEXTLINE(readability-suspicious-call-argument) */
phn_next_set(tail, phn0, offset);
tail = phn0;
phn0 = head;
phn1 = phn_next_get(phn0, offset);
}
}
return phn0;
}