lib/sort.c optimization
Hello, I fixed and tested a small bug in lib/sort.c file, heap sort
function.
The fix avoids unnecessary swap of contents when i is 0 (saves few loads
and stores), which happens every time sort function is called. I felt the
fix is worth bringing it to your attention given the importance and
frequent use of the sort function.
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/lib/sort.c b/lib/sort.c
index 9615678..6abbaf3 100644
--- a/lib/sort.c
+++ b/lib/sort.c
@@ -67,7 +67,7 @@
}
/* sort */
- for (i = n - size; i >= 0; i -= size) {
+ for (i = n - size; i > 0; i -= size) {
swap(base, base + i, size);
for (r = 0; r * 2 + size < i; r = c) {
c = r * 2 + size;