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-rw-r--r--ports/sysdeps/arm/armv6t2/ffs.S35
1 files changed, 35 insertions, 0 deletions
diff --git a/ports/sysdeps/arm/armv6t2/ffs.S b/ports/sysdeps/arm/armv6t2/ffs.S
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--- /dev/null
+++ b/ports/sysdeps/arm/armv6t2/ffs.S
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+/* ffs -- find first set bit in an int, from least significant end.
+   Copyright (C) 2013 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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 <sysdep.h>
+
+	.syntax unified
+	.text
+
+ENTRY (__ffs)
+	cmp	r0, #0
+	rbit	r0, r0
+	itt	ne
+	clzne	r0, r0
+	addne	r0, r0, #1
+	bx	lr
+END (__ffs)
+
+weak_alias (__ffs, ffs)
+weak_alias (__ffs, ffsl)
+libc_hidden_builtin_def (ffs)