diff options
Diffstat (limited to 'REORG.TODO/sysdeps/s390/ffs.c')
-rw-r--r-- | REORG.TODO/sysdeps/s390/ffs.c | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/s390/ffs.c b/REORG.TODO/sysdeps/s390/ffs.c new file mode 100644 index 0000000000..c36f60045b --- /dev/null +++ b/REORG.TODO/sysdeps/s390/ffs.c @@ -0,0 +1,70 @@ +/* ffs -- find first set bit in a word, counted from least significant end. + S/390 version. + Copyright (C) 2000-2017 Free Software Foundation, Inc. + Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com). + 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 <limits.h> +#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 (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) +libc_hidden_def (__ffs) +libc_hidden_builtin_def (ffs) +#if ULONG_MAX == UINT_MAX +#undef ffsl +weak_alias (__ffs, ffsl) +#endif |