1 files changed, 39 insertions, 0 deletions
diff --git a/ports/sysdeps/tile/tilepro/strlen.c b/ports/sysdeps/tile/tilepro/strlen.c
new file mode 100644
index 0000000000..8e53b51aea
--- /dev/null
+++ b/ports/sysdeps/tile/tilepro/strlen.c
@@ -0,0 +1,39 @@
+/* Copyright (C) 2011 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <string.h>
+#include <stdint.h>
+
+size_t
+strlen (const char *s)
+{
+  /* Get an aligned pointer. */
+  const uintptr_t s_int = (uintptr_t) s;
+  const uint32_t *p = (const uint32_t *) (s_int & -4);
+
+  /* Read the first word, but force bytes before the string to be nonzero.
+     This expression works because we know shift counts are taken mod 32.  */
+  uint32_t v = *p | ((1 << (s_int << 3)) - 1);
+
+  uint32_t bits;
+  while ((bits = __insn_seqb (v, 0)) == 0)
+    v = *++p;
+
+  return ((const char *) p) + (__insn_ctz (bits) >> 3) - s;
+}
+libc_hidden_builtin_def (strlen)