diff options
Diffstat (limited to 'lib/libc/powerpc64/string/memcpy.S')
| -rw-r--r-- | lib/libc/powerpc64/string/memcpy.S | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/lib/libc/powerpc64/string/memcpy.S b/lib/libc/powerpc64/string/memcpy.S new file mode 100644 index 000000000000..28f3f2bb0ab4 --- /dev/null +++ b/lib/libc/powerpc64/string/memcpy.S @@ -0,0 +1,131 @@ +/*- + * Copyright (c) 2018 Instituto de Pesquisas Eldorado + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the author nor the names of its contributors may + * be used to endorse or promote products derived from this software + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + */ + +#include <machine/asm.h> +#ifndef FN_NAME +#define FN_NAME __memcpy +WEAK_REFERENCE(__memcpy, memcpy); +#define BLOCK_BITS 4 +#endif + +#define BLOCK_BYTES (1 << BLOCK_BITS) +#define BLOCK_MASK (BLOCK_BYTES - 1) + +/* Minimum 8 byte alignment, to avoid cache-inhibited alignment faults. */ +#ifndef ALIGN_MASK +#define ALIGN_MASK 0x7 +#endif + +/* + * r3: dst + * r4: src + * r5: len + */ +ENTRY(FN_NAME) + cmpdi %r5, 0 /* len == 0? nothing to do */ + beqlr- + + /* If src and dst are relatively misaligned, do byte copies. */ + andi. %r8, %r3, ALIGN_MASK + andi. %r7, %r4, ALIGN_MASK + cmpd %r8, %r7 + mr %r7, %r5 + mr %r8, %r3 /* save dst */ + bne .Lcopy_remaining_fix_index_byte + + /* align src */ +.Lalignment_loop: + lbz %r6, 0(%r4) + stb %r6, 0(%r3) + addi %r3, %r3, 1 + addi %r4, %r4, 1 + addi %r5, %r5, -1 + cmpdi %r5, 0 + beq .Lexit + andi. %r0, %r4, BLOCK_MASK + bne .Lalignment_loop + + /* r7 = remaining, non-block, bytes */ + andi. %r7, %r5, BLOCK_MASK + + /* Check if there are blocks of BLOCK_BYTES to be copied */ + xor. %r5, %r5, %r7 + beq .Lcopy_remaining_fix_index_byte + +#ifdef FN_COPY_LOOP +FN_COPY_LOOP +#else + /* Setup to copy word with ldu and stdu */ + ld %r6, 0(%r4) + ld %r9, 8(%r4) + std %r6, 0(%r3) + std %r9, 8(%r3) + addi %r5, %r5, -BLOCK_BYTES + cmpd %r5, 0 + beq .Lcopy_remaining_fix_index_word + + srdi %r5, %r5, BLOCK_BITS + mtctr %r5 +.Lcopy_word: + ldu %r6, 16(%r4) + ld %r9, 8(%r4) + stdu %r6, 16(%r3) + std %r9, 8(%r3) + bdnz .Lcopy_word + +.Lcopy_remaining_fix_index_word: + /* Check if there are remaining bytes */ + cmpd %r7, 0 + beq .Lexit + addi %r3, %r3, BLOCK_MASK + addi %r4, %r4, BLOCK_MASK + b .Lcopy_remaining +#endif + +.Lcopy_remaining_fix_index_byte: + addi %r4, %r4, -1 + addi %r3, %r3, -1 + + /* Copy remaining bytes */ +.Lcopy_remaining: + mtctr %r7 +.Lcopy_remaining_loop: + lbzu %r6, 1(%r4) + stbu %r6, 1(%r3) + bdnz .Lcopy_remaining_loop + +.Lexit: + /* Restore dst */ + mr %r3, %r8 + blr + +END(FN_NAME) + + .section .note.GNU-stack,"",%progbits + |