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>

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>
Subbaiah Venkata · Linus Torvalds
1 parent e30618cbd1
Showing 1 changed file with 1 additions and 1 deletions Side-by-side Diff
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;
...	...	@@ -67,7 +67,7 @@
67	67	}
68	68
69	69	/* sort */
70		- for (i = n - size; i >= 0; i -= size) {
	70	+ for (i = n - size; i > 0; i -= size) {
71	71	swap(base, base + i, size);
72	72	for (r = 0; r * 2 + size < i; r = c) {
73	73	c = r * 2 + size;