1 files changed, 34 insertions, 0 deletions
diff --git a/bits.c b/bits.c
new file mode 100644
index 0000000..bde2e71
--- /dev/null
+++ b/bits.c
@@ -0,0 +1,34 @@
+/*
+ * This file is part of ltrace.
+ * Copyright (C) 2013 Petr Machata, Red Hat Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include "bits.h"
+
+/* This is called rarely, and any overhead will be lost in ptrace
+ * noise, so the algorithm doesn't need to be terribly clever.  For
+ * the same reason we don't bother defining the corresponding _32
+ * variant.  */
+unsigned
+bitcount(uint64_t u)
+{
+	int c = 0;
+	for (; u > 0; u &= u - 1)
+		c++;
+	return c;
+}