diff options
Diffstat (limited to 'sysdeps/loongarch/lp64/multiarch/strlen-aligned.S')
| -rw-r--r-- | sysdeps/loongarch/lp64/multiarch/strlen-aligned.S | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/sysdeps/loongarch/lp64/multiarch/strlen-aligned.S b/sysdeps/loongarch/lp64/multiarch/strlen-aligned.S new file mode 100644 index 0000000000..e9e1d2fc04 --- /dev/null +++ b/sysdeps/loongarch/lp64/multiarch/strlen-aligned.S @@ -0,0 +1,100 @@ +/* Optimized strlen implementation using basic Loongarch instructions. + Copyright (C) 2023 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 + <https://www.gnu.org/licenses/>. */ + +#include <sysdep.h> +#include <sys/regdef.h> +#include <sys/asm.h> + +#if IS_IN (libc) +# define STRLEN __strlen_aligned +#else +# define STRLEN strlen +#endif + +LEAF(STRLEN, 6) + move a1, a0 + bstrins.d a0, zero, 2, 0 + lu12i.w a2, 0x01010 + li.w t0, -1 + + ld.d t2, a0, 0 + andi t1, a1, 0x7 + ori a2, a2, 0x101 + slli.d t1, t1, 3 + + bstrins.d a2, a2, 63, 32 + sll.d t1, t0, t1 + slli.d t3, a2, 7 + nor a3, zero, t3 + + orn t2, t2, t1 + sub.d t0, t2, a2 + nor t1, t2, a3 + and t0, t0, t1 + + + bnez t0, L(count_pos) + addi.d a0, a0, 8 +L(loop_16_7bit): + ld.d t2, a0, 0 + sub.d t1, t2, a2 + + and t0, t1, t3 + bnez t0, L(more_check) + ld.d t2, a0, 8 + sub.d t1, t2, a2 + + and t0, t1, t3 + addi.d a0, a0, 16 + beqz t0, L(loop_16_7bit) + addi.d a0, a0, -8 + +L(more_check): + nor t0, t2, a3 + and t0, t1, t0 + bnez t0, L(count_pos) + addi.d a0, a0, 8 + + +L(loop_16_8bit): + ld.d t2, a0, 0 + sub.d t1, t2, a2 + nor t0, t2, a3 + and t0, t0, t1 + + bnez t0, L(count_pos) + ld.d t2, a0, 8 + addi.d a0, a0, 16 + sub.d t1, t2, a2 + + nor t0, t2, a3 + and t0, t0, t1 + beqz t0, L(loop_16_8bit) + addi.d a0, a0, -8 + +L(count_pos): + ctz.d t1, t0 + sub.d a0, a0, a1 + srli.d t1, t1, 3 + add.d a0, a0, t1 + + jr ra +END(STRLEN) + +libc_hidden_builtin_def (STRLEN) |