diff options
Diffstat (limited to 'sysdeps/csky/abiv2/memset.S')
| -rw-r--r-- | sysdeps/csky/abiv2/memset.S | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/sysdeps/csky/abiv2/memset.S b/sysdeps/csky/abiv2/memset.S new file mode 100644 index 0000000000..dd54a4e99b --- /dev/null +++ b/sysdeps/csky/abiv2/memset.S @@ -0,0 +1,98 @@ +/* The assembly function for memset. C-SKY ABIV2 version. + Copyright (C) 2018 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> + +ENTRY (memset) + /* Test if len less than 4 bytes. */ + mov r12, r0 + cmplti r2, 8 + bt .L_set_by_byte + + andi r13, r0, 3 + movi r19, 4 + /* Test if dest is not 4 bytes aligned. */ + bnez r13, .L_dest_not_aligned + /* Hardware can handle unaligned access directly. */ +.L_dest_aligned: + zextb r1, r1 + mov r3, r1 + lsli r1, 8 + or r1, r3 + lsli r3, r1, 16 + or r3, r1 + + /* If dest is aligned, then copy. */ + zext r18, r2, 31, 4 + /* Test if len less than 16 bytes. */ + bez r18, .L_len_less_16bytes + + LABLE_ALIGN +.L_len_larger_16bytes: + stw r3, (r0, 0) + stw r3, (r0, 4) + stw r3, (r0, 8) + stw r3, (r0, 12) + PRE_BNEZAD (r18) + addi r0, 16 + BNEZAD (r18, .L_len_larger_16bytes) + +.L_len_less_16bytes: + zext r18, r2, 3, 2 + andi r2, 3 + bez r18, .L_set_by_byte +.L_len_less_16bytes_loop: + stw r3, (r0, 0) + PRE_BNEZAD (r18) + addi r0, 4 + BNEZAD (r18, .L_len_less_16bytes_loop) + + /* Test if len less than 4 bytes. */ +.L_set_by_byte: + zext r18, r2, 2, 0 + bez r18, .L_return +.L_set_by_byte_loop: + stb r1, (r0, 0) + PRE_BNEZAD (r18) + addi r0, 1 + BNEZAD (r18, .L_set_by_byte_loop) + +.L_return: + mov r0, r12 + rts + + /* If dest is not aligned, just set some bytes makes the dest + align. */ + +.L_dest_not_aligned: + sub r13, r19, r13 + sub r2, r13 +.L_dest_not_aligned_loop: + /* Makes the dest align. */ + stb r1, (r0, 0) + PRE_BNEZAD (r13) + addi r0, 1 + BNEZAD (r13, .L_dest_not_aligned_loop) + cmplti r2, 8 + bt .L_set_by_byte + /* Check whether the src is aligned. */ + br .L_dest_aligned +END (memset) + +libc_hidden_builtin_def (memset) +.weak memset |