set.matched() runs a binary search.

src/vmod_re2.c

@@ -768,7 +768,7 @@ VCL_BOOL
 vmod_set_matched(VRT_CTX, struct vmod_re2_set *set, VCL_INT n)
 {
 	struct task_set_match *task;
-	unsigned i;
+	int hi, lo = 0;
 
 	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);
 	CHECK_OBJ_NOTNULL(set, VMOD_RE2_SET_MAGIC);
@@ -789,9 +789,18 @@ vmod_set_matched(VRT_CTX, struct vmod_re2_set *set, VCL_INT n)
 	WS_Assert_Allocated(ctx->ws, task->matches,
 			    task->nmatches * sizeof(int));
 	n--;
-	for (i = 0; i < task->nmatches && task->matches[i] < n; i++)
-		;
-	return task->matches[i] == n;
+	hi = task->nmatches;
+	do {
+		int m = lo + (hi - lo) / 2;
+		if (task->matches[m] == n)
+			return 1;
+		if (task->matches[m] < n)
+			lo = m + 1;
+		else
+			hi = m - 1;
+	} while (lo <= hi);
+
+	return 0;
 }
 
 VCL_INT