HAOUAS Elyes has uploaded this change for review.
payloads/libpayload/libc: uppgrade qsort.c to v1.15
Change-Id: I3ab8d4b2c5ac782b949e244749ca285ed4700283
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
---
M payloads/libpayload/libc/qsort.c
1 file changed, 42 insertions(+), 37 deletions(-)
git pull ssh://review.coreboot.org:29418/coreboot refs/changes/17/43717/1
diff --git a/payloads/libpayload/libc/qsort.c b/payloads/libpayload/libc/qsort.c
index aad2aa3..51d67bc 100644
--- a/payloads/libpayload/libc/qsort.c
+++ b/payloads/libpayload/libc/qsort.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: qsort.c,v 1.11 2010/02/08 11:04:07 otto Exp $ */
+/* $OpenBSD: qsort.c,v 1.15 2017/05/17 16:58:20 millert Exp $ */
/*-
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
@@ -39,11 +39,11 @@
/*
* Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
*/
-#define swapcode(TYPE, parmi, parmj, n) { \
- size_t i = (n) / sizeof (TYPE); \
- TYPE *pi = (TYPE *) (parmi); \
- TYPE *pj = (TYPE *) (parmj); \
- do { \
+#define swapcode(TYPE, parmi, parmj, n) { \
+ size_t i = (n) / sizeof(TYPE); \
+ TYPE *pi = (TYPE *) (parmi); \
+ TYPE *pj = (TYPE *) (parmj); \
+ do { \
TYPE t = *pi; \
*pi++ = *pj; \
*pj++ = t; \
@@ -70,7 +70,7 @@
} else \
swapfunc(a, b, es, swaptype)
-#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype)
+#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype)
static __inline char *
med3(char *a, char *b, char *c, int (*cmp)(const void *, const void *))
@@ -84,23 +84,22 @@
qsort(void *aa, size_t n, size_t es, int (*cmp)(const void *, const void *))
{
char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
- int cmp_result, swaptype, swap_cnt;
- size_t d, r;
+ int cmp_result, swaptype;
+ size_t d, r, s;
char *a = aa;
loop: SWAPINIT(a, es);
- swap_cnt = 0;
if (n < 7) {
- for (pm = (char *)a + es; pm < (char *) a + n * es; pm += es)
- for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
+ for (pm = a + es; pm < a + n * es; pm += es)
+ for (pl = pm; pl > a && cmp(pl - es, pl) > 0;
pl -= es)
swap(pl, pl - es);
return;
}
- pm = (char *)a + (n / 2) * es;
+ pm = a + (n / 2) * es;
if (n > 7) {
- pl = (char *)a;
- pn = (char *)a + (n - 1) * es;
+ pl = a;
+ pn = a + (n - 1) * es;
if (n > 40) {
d = (n / 8) * es;
pl = med3(pl, pl + d, pl + 2 * d, cmp);
@@ -110,13 +109,12 @@
pm = med3(pl, pm, pn, cmp);
}
swap(a, pm);
- pa = pb = (char *)a + es;
+ pa = pb = a + es;
- pc = pd = (char *)a + (n - 1) * es;
+ pc = pd = a + (n - 1) * es;
for (;;) {
while (pb <= pc && (cmp_result = cmp(pb, a)) <= 0) {
if (cmp_result == 0) {
- swap_cnt = 1;
swap(pa, pb);
pa += es;
}
@@ -124,7 +122,6 @@
}
while (pb <= pc && (cmp_result = cmp(pc, a)) >= 0) {
if (cmp_result == 0) {
- swap_cnt = 1;
swap(pc, pd);
pd -= es;
}
@@ -133,30 +130,38 @@
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(pl - es, pl) > 0;
- pl -= es)
- swap(pl, pl - es);
- return;
- }
- pn = (char *)a + n * es;
- r = min(pa - (char *)a, pb - pa);
+ pn = a + n * es;
+ r = min(pa - a, pb - pa);
vecswap(a, pb - r, r);
r = min(pd - pc, pn - pd - es);
vecswap(pb, pn - r, r);
- if ((r = pb - pa) > es)
- qsort(a, r / es, es, cmp);
- if ((r = pd - pc) > es) {
- /* Iterate rather than recurse to save stack space */
- a = pn - r;
- n = r / es;
- goto loop;
+ /*
+ * To save stack space we sort the smaller side of the partition first
+ * using recursion and eliminate tail recursion for the larger side.
+ */
+ r = pb - pa;
+ s = pd - pc;
+ if (r < s) {
+ /* Recurse for 1st side, iterate for 2nd side. */
+ if (s > es) {
+ if (r > es)
+ qsort(a, r / es, es, cmp);
+ a = pn - s;
+ n = s / es;
+ goto loop;
+ }
+ } else {
+ /* Recurse for 2nd side, iterate for 1st side. */
+ if (r > es) {
+ if (s > es)
+ qsort(pn - s, s / es, es, cmp);
+ n = r / es;
+ goto loop;
+ }
}
-/* qsort(pn - r, r / es, es, cmp);*/
}
+DEF_STRONG(qsort);
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