Add instrumentation

Track the number of comparisons, swaps, and rotations performed in each
part of the sorting algorithm.

1 files changed, 38 insertions, 0 deletions

diff --git a/counts.c b/counts.c
new file mode 100644
index 0000000..d1f3910
--- /dev/null
+++ b/counts.c
@@ -0,0 +1,38 @@
+#include <stdint.h>
+#include <stdio.h>
+
+#include "counts.h"
+
+struct counts counts[MAX_COUNTS];
+
+static void clear(struct counts *c)
+{
+	*c = (struct counts) {0};
+}
+
+void clear_all_counts(void)
+{
+	for (int i = 0; i < MAX_COUNTS; i++)
+		clear(counts+i);
+}
+
+void clear_accumulator(void)
+{
+	clear(counts);
+}
+
+void add_counts(struct counts *target, struct counts *snapshot)
+{
+	target->compare += counts[CURRENT].compare - snapshot->compare;
+	target->rotate  += counts[CURRENT].rotate  - snapshot->rotate;
+	target->swap    += counts[CURRENT].swap    - snapshot->swap;
+}
+
+void print_counts(void)
+{
+	char *labels[] = {"total", "sortnet", "overlap", "merge", "move buffer", "distribute"};
+	for (int i = 0; i < MAX_COUNTS; i++) {
+		const struct counts *c = counts+i;
+		dprintf(42, "%12s: %10lu cmp, %10lu swap, %10lu rotate\n", labels[i], c->compare, c->swap, c->rotate);
+	}
+}