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- /*
- * Copyright (C) 2016 Andes Technology, Inc.
- * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
- */
- #include <sysdep.h>
- !==========================================================
- ! void *memcpy(void *dst, const void *src, int n);
- !
- ! dst: $r0
- ! src: $r1
- ! n : $r2
- ! ret: $r0 - pointer to the memory area dst.
- !==========================================================
- .weak memcpy
- ENTRY(memcpy)
- move $r5, $r0
- beq $r0, $r1, .Lquit_memcpy
- beqz $r2, .Lquit_memcpy
- srli $r3, $r2, #5 ! check if len < cache-line size 32
- beqz $r3, .Lword_copy_entry
- andi $r4, $r0, #0x3 ! check byte-align
- beqz $r4, .Lunalign_word_copy_entry
- addi $r4, $r4, #-4
- abs $r4, $r4 ! check how many un-align byte to copy
- sub $r2, $r2, $r4 ! update $R2
- .Lunalign_byte_copy:
- lbi.bi $r3, [$r1], #1
- addi $r4, $r4, #-1
- sbi.bi $r3, [$r0], #1
- bnez $r4, .Lunalign_byte_copy
- beqz $r2, .Lquit_memcpy
- .Lunalign_word_copy_entry:
- andi $r3, $r0, 0x1f ! check cache-line unaligncount
- beqz $r3, .Lcache_copy
- addi $r3, $r3, #-32
- abs $r3, $r3
- sub $r2, $r2, $r3 ! update $R2
- .Lunalign_word_copy:
- lmw.bim $r4, [$r1], $r4
- addi $r3, $r3, #-4
- smw.bim $r4, [$r0], $r4
- bnez $r3, .Lunalign_word_copy
- beqz $r2, .Lquit_memcpy
- addi $r3, $r2, #-32 ! to check $r2 < cache_line, than go to .Lword_copy
- bltz $r3, .Lword_copy_entry
- .Lcache_copy:
- srli $r3, $r2, #5
- beqz $r3, .Lword_copy_entry
- pushm $r6, $r13
- .L3:
- lmw.bim $r6, [$r1], $r13
- addi $r3, $r3, #-1
- smw.bim $r6, [$r0], $r13
- bnez $r3, .L3
- popm $r6, $r13
- .Lword_copy_entry:
- andi $r2, $r2, #31
- beqz $r2, .Lquit_memcpy
- srli $r3, $r2, #2
- beqz $r3, .Lbyte_copy
- .Lword_copy:
- lmw.bim $r4, [$r1], $r4
- addi $r3, $r3, #-1
- smw.bim $r4, [$r0], $r4
- bnez $r3, .Lword_copy
- andi $r2, $r2, #3
- beqz $r2, .Lquit_memcpy
- .Lbyte_copy:
- lbi.bi $r3, [$r1], #1
- addi $r2, $r2, #-1
- sbi.bi $r3, [$r0], #1
- bnez $r2, .Lbyte_copy
- .Lquit_memcpy:
- move $r0, $r5
- ret
- END(memcpy)
- libc_hidden_def(memcpy)
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