/* Optimized memset for PowerPC476 (128-byte cacheline).

   Copyright (C) 2010-2018 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>

/* memset

       r3:destination address and return address

       r4:source integer to copy

       r5:byte count

       r11:sources integer to copy in all 32 bits of reg

       r12:temp return address

       Save return address in r12

       If destinationn is unaligned and count is greater tha 255 bytes

       set 0-3 bytes to make destination aligned

       If count is greater tha 255 bytes and setting zero to memory

       use dbcz to set memeory when we can

       otherwsie do the follwoing

       If 16 or more words to set we use 16 word copy loop.

       Finaly we set 0-15 extra bytes with string store. */

EALIGN (memset, 5, 0)

       rlwinm  r11,r4,0,24,31

       rlwimi  r11,r4,8,16,23

       rlwimi  r11,r11,16,0,15

       addi    r12,r3,0

       cmpwi   r5,0x00FF

       ble     L(preword8_count_loop)

       cmpwi   r4,0x00

       beq     L(use_dcbz)

       neg     r6,r3

       clrlwi. r6,r6,30

       beq     L(preword8_count_loop)

       addi    r8,0,1

       mtctr   r6

       subi    r3,r3,1

L(unaligned_bytecopy_loop):

       stbu    r11,0x1(r3)

       subf.   r5,r8,r5

       beq     L(end_memset)

       bdnz    L(unaligned_bytecopy_loop)

       addi    r3,r3,1

L(preword8_count_loop):

       srwi.   r6,r5,4

       beq     L(preword2_count_loop)

       mtctr   r6

       addi    r3,r3,-4

       mr      r8,r11

       mr      r9,r11

       mr      r10,r11

L(word8_count_loop_no_dcbt):

       stwu    r8,4(r3)

       stwu    r9,4(r3)

       subi    r5,r5,0x10

       stwu    r10,4(r3)

       stwu    r11,4(r3)

       bdnz    L(word8_count_loop_no_dcbt)

       addi    r3,r3,4

L(preword2_count_loop):

       clrlwi. r7,r5,28

       beq     L(end_memset)

       mr      r8,r11

       mr      r9,r11

       mr      r10,r11

       mtxer   r7

       stswx   r8,0,r3

L(end_memset):

       addi    r3,r12,0

       blr

L(use_dcbz):

       neg     r6,r3

       clrlwi. r7,r6,28

       beq     L(skip_string_loop)

       mr      r8,r11

       mr      r9,r11

       mr      r10,r11

       subf    r5,r7,r5

       mtxer   r7

       stswx   r8,0,r3

       add     r3,r3,r7

L(skip_string_loop):

       clrlwi  r8,r6,25

       srwi.   r8,r8,4

       beq     L(dcbz_pre_loop)

       mtctr   r8

L(word_loop):

       stw     r11,0(r3)

       subi    r5,r5,0x10

       stw     r11,4(r3)

       stw     r11,8(r3)

       stw     r11,12(r3)

       addi    r3,r3,0x10

       bdnz    L(word_loop)

L(dcbz_pre_loop):

       srwi    r6,r5,7

       mtctr   r6

       addi    r7,0,0

L(dcbz_loop):

       dcbz    r3,r7

       addi    r3,r3,0x80

       subi    r5,r5,0x80

       bdnz    L(dcbz_loop)

       srwi.   r6,r5,4

       beq     L(postword2_count_loop)

       mtctr   r6

L(postword8_count_loop):

       stw     r11,0(r3)

       subi    r5,r5,0x10

       stw     r11,4(r3)

       stw     r11,8(r3)

       stw     r11,12(r3)

       addi    r3,r3,0x10

       bdnz    L(postword8_count_loop)

L(postword2_count_loop):

       clrlwi. r7,r5,28

       beq     L(end_memset)

       mr      r8,r11

       mr      r9,r11

       mr      r10,r11

       mtxer   r7

       stswx   r8,0,r3

       b       L(end_memset)

END (memset)

libc_hidden_builtin_def (memset)