diff options
Diffstat (limited to 'sysdeps/csky/abiv2/strcmp.S')
-rw-r--r-- | sysdeps/csky/abiv2/strcmp.S | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/sysdeps/csky/abiv2/strcmp.S b/sysdeps/csky/abiv2/strcmp.S new file mode 100644 index 0000000000..b0fee81b43 --- /dev/null +++ b/sysdeps/csky/abiv2/strcmp.S @@ -0,0 +1,156 @@ +/* The assembly function for string compare. 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 (strcmp) + mov a3, a0 + /* Check if the s1 addr is aligned. */ + xor a2, a3, a1 + andi a2, 0x3 + bnez a2, 7f + andi t1, a0, 0x3 + bnez t1, 5f + +1: + /* If aligned, load word each time. */ + ldw t0, (a3, 0) + ldw t1, (a1, 0) + /* If s1[i] != s2[i], goto 2f. */ + cmpne t0, t1 + bt 2f + /* If s1[i] == s2[i], check if s1 or s2 is at the end. */ + tstnbz t0 + /* If at the end, goto 3f (finish comparing). */ + bf 3f + + ldw t0, (a3, 4) + ldw t1, (a1, 4) + cmpne t0, t1 + bt 2f + tstnbz t0 + bf 3f + + ldw t0, (a3, 8) + ldw t1, (a1, 8) + cmpne t0, t1 + bt 2f + tstnbz t0 + bf 3f + + ldw t0, (a3, 12) + ldw t1, (a1, 12) + cmpne t0, t1 + bt 2f + tstnbz t0 + bf 3f + + ldw t0, (a3, 16) + ldw t1, (a1, 16) + cmpne t0, t1 + bt 2f + tstnbz t0 + bf 3f + + ldw t0, (a3, 20) + ldw t1, (a1, 20) + cmpne t0, t1 + bt 2f + tstnbz t0 + bf 3f + + ldw t0, (a3, 24) + ldw t1, (a1, 24) + cmpne t0, t1 + bt 2f + tstnbz t0 + bf 3f + + ldw t0, (a3, 28) + ldw t1, (a1, 28) + cmpne t0, t1 + bt 2f + tstnbz t0 + bf 3f + + addi a3, 32 + addi a1, 32 + + br 1b + + /* s1[i] != s2[i] in word, so we check byte 3. */ +2: + xtrb3 a0, t0 + xtrb3 a2, t1 + subu a0, a2 + bez a2, 4f + bnez a0, 4f + + /* Check byte 2. */ + xtrb2 a0, t0 + xtrb2 a2, t1 + subu a0, a2 + bez a2, 4f + bnez a0, 4f + + /* Check byte 1. */ + xtrb1 a0, t0 + xtrb1 a2, t1 + subu a0, a2 + bez a2, 4f + bnez a0, 4f + + /* Check byte 0. */ + xtrb0 a0, t0 + xtrb0 a2, t1 + subu a0, a2 + + jmp lr +3: + movi a0, 0 +4: + jmp lr + + /* Compare when s1 or s2 is not aligned. */ +5: + subi t1, 4 +6: + ldb a0, (a3, 0) + ldb a2, (a1, 0) + subu a0, a2 + bnez a0, 4b + addi t1, 1 + bez a2, 4b + addi a1, 1 + addi a3, 1 + bez t1, 1b + br 6b + +7: + ldb a0, (a3, 0) + addi a3, 1 + ldb a2, (a1, 0) + addi a1, 1 + subu a0, a2 + bnez a0, 4b + bnez a2, 7b + jmp r15 +END (strcmp) + +libc_hidden_def (strcmp) +.weak strcmp |