1 files changed, 68 insertions, 0 deletions
diff --git a/sysdeps/s390/ffs.c b/sysdeps/s390/ffs.c
new file mode 100644
index 0000000000..b6ed821e58
--- /dev/null
+++ b/sysdeps/s390/ffs.c
@@ -0,0 +1,68 @@
+/* ffs -- find first set bit in a word, counted from least significant end.
+   This file is part of the GNU C Library.
+   Copyright (C) 2000 Free Software Foundation, Inc.
+   Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#define ffsl __something_else
+#include <string.h>
+
+#undef	ffs
+
+/*
+ * ffs: find first bit set. This is defined the same way as
+ * the libc and compiler builtin ffs routines, therefore
+ * differs in spirit from the above ffz (man ffs).
+ */
+
+int
+__ffs (x)
+     int x;
+{
+  int r;
+
+  if (x == 0)
+    return 0;
+  __asm__("    lr   %%r1,%1\n"
+	  "    sr   %0,%0\n"
+	  "    tml  %%r1,0xFFFF\n"
+	  "    jnz  0f\n"
+	  "    ahi  %0,16\n"
+	  "    srl  %%r1,16\n"
+	  "0:  tml  %%r1,0x00FF\n"
+	  "    jnz  1f\n"
+	  "    ahi  %0,8\n"
+	  "    srl  %%r1,8\n"
+	  "1:  tml  %%r1,0x000F\n"
+	  "    jnz  2f\n"
+	  "    ahi  %0,4\n"
+	  "    srl  %%r1,4\n"
+	  "2:  tml  %%r1,0x0003\n"
+	  "    jnz  3f\n"
+	  "    ahi  %0,2\n"
+	  "    srl  %%r1,2\n"
+	  "3:  tml  %%r1,0x0001\n"
+	  "    jnz  4f\n"
+	  "    ahi  %0,1\n"
+	  "4:"
+	  : "=&d" (r) : "d" (x) : "cc", "1" );
+  return r+1;
+}
+
+weak_alias (__ffs, ffs)
+#undef ffsl
+weak_alias (__ffs, ffsl)