git: 935c26dbe3a6 - stable/14 - libkern: Drop incorrect qsort optimization

The branch stable/14 has been updated by des:

URL: https://cgit.FreeBSD.org/src/commit/?id=935c26dbe3a6ce77cda9bd802fa45cdb938610a6

commit 935c26dbe3a6ce77cda9bd802fa45cdb938610a6
Author:     Dag-Erling Smørgrav <des@FreeBSD.org>
AuthorDate: 2025-08-15 18:01:02 +0000
Commit:     Dag-Erling Smørgrav <des@FreeBSD.org>
CommitDate: 2025-08-27 18:49:58 +0000

    libkern: Drop incorrect qsort optimization
    
    See 5205b32de3fb for details.
    
    PR:             287089
    MFC after:      1 week
    Reviewed by:    jlduran
    Differential Revision:  https://reviews.freebsd.org/D51919
    
    (cherry picked from commit ef8f3e913156aa268e07ae1daa68e3bc3f1c4d29)
---
 sys/libkern/qsort.c | 14 +-------------
 1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/sys/libkern/qsort.c b/sys/libkern/qsort.c
index 2707d2ecb738..71cdceaa33dc 100644
--- a/sys/libkern/qsort.c
+++ b/sys/libkern/qsort.c
@@ -115,11 +115,10 @@ qsort(void *a, size_t n, size_t es, cmp_t *cmp)
 	char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
 	size_t d1, d2;
 	int cmp_result;
-	int swaptype_long, swaptype_int, swap_cnt;
+	int swaptype_long, swaptype_int;
 
 loop:	SWAPINIT(long, a, es);
 	SWAPINIT(int, a, es);
-	swap_cnt = 0;
 	if (n < 7) {
 		for (pm = (char *)a + es; pm < (char *)a + n * es; pm += es)
 			for (pl = pm; 
@@ -148,7 +147,6 @@ loop:	SWAPINIT(long, a, es);
 	for (;;) {
 		while (pb <= pc && (cmp_result = CMP(thunk, pb, a)) <= 0) {
 			if (cmp_result == 0) {
-				swap_cnt = 1;
 				swap(pa, pb);
 				pa += es;
 			}
@@ -156,7 +154,6 @@ loop:	SWAPINIT(long, a, es);
 		}
 		while (pb <= pc && (cmp_result = CMP(thunk, pc, a)) >= 0) {
 			if (cmp_result == 0) {
-				swap_cnt = 1;
 				swap(pc, pd);
 				pd -= es;
 			}
@@ -165,18 +162,9 @@ loop:	SWAPINIT(long, a, es);
 		if (pb > pc)
 			break;
 		swap(pb, pc);
-		swap_cnt = 1;
 		pb += es;
 		pc -= es;
 	}
-	if (swap_cnt == 0) {  /* Switch to insertion sort */
-		for (pm = (char *)a + es; pm < (char *)a + n * es; pm += es)
-			for (pl = pm; 
-			     pl > (char *)a && CMP(thunk, pl - es, pl) > 0;
-			     pl -= es)
-				swap(pl, pl - es);
-		return;
-	}
 
 	pn = (char *)a + n * es;
 	d1 = MIN(pa - (char *)a, pb - pa);