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-rw-r--r--REORG.TODO/sysdeps/x86_64/ffs.c39
1 files changed, 39 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/x86_64/ffs.c b/REORG.TODO/sysdeps/x86_64/ffs.c
new file mode 100644
index 0000000000..132812c488
--- /dev/null
+++ b/REORG.TODO/sysdeps/x86_64/ffs.c
@@ -0,0 +1,39 @@
+/* ffs -- find first set bit in a word, counted from least significant end.
+ For AMD x86-64.
+ This file is part of the GNU C Library.
+ Copyright (C) 1991-2017 Free Software Foundation, Inc.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>.
+
+ 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>
+
+#undef ffs
+
+int
+__ffs (int x)
+{
+ int cnt;
+ int tmp;
+
+ asm ("bsfl %2,%0\n" /* Count low bits in X and store in %1. */
+ "cmovel %1,%0\n" /* If number was zero, use -1 as result. */
+ : "=&r" (cnt), "=r" (tmp) : "rm" (x), "1" (-1));
+
+ return cnt + 1;
+}
+weak_alias (__ffs, ffs)
+libc_hidden_def (__ffs)
+libc_hidden_builtin_def (ffs)