/* Optimized memset implementation using LoongArch LASX instructions.
   Copyright (C) 2023-2026 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
   <https://www.gnu.org/licenses/>.  */

#include <sysdep.h>
#include <sys/regdef.h>
#include <sys/asm.h>

#if IS_IN (libc) && !defined __loongarch_soft_float

# define MEMSET __memset_lasx

LEAF(MEMSET, 6)
    li.d            t1, 32
    move            a3, a0
    xvreplgr2vr.b   xr0, a1
    add.d           a4, a0, a2

    bgeu            t1, a2, L(less_32bytes)
    li.d            t3, 128
    li.d            t2, 64
    blt             t3, a2, L(long_bytes)

L(less_128bytes):
    bgeu            t2, a2, L(less_64bytes)
    xvst            xr0, a3, 0
    xvst            xr0, a3, 32
    xvst            xr0, a4, -32

    xvst            xr0, a4, -64
    jr              ra
L(less_64bytes):
    xvst            xr0, a3, 0
    xvst            xr0, a4, -32


    jr              ra
L(less_32bytes):
    srli.d          t0, a2, 4
    beqz            t0, L(less_16bytes)
    vst             vr0, a3, 0

    vst             vr0, a4, -16
    jr              ra
L(less_16bytes):
    srli.d          t0, a2, 3
    beqz            t0, L(less_8bytes)

    vstelm.d        vr0, a3, 0, 0
    vstelm.d        vr0, a4, -8, 0
    jr              ra
L(less_8bytes):
    srli.d          t0, a2, 2

    beqz            t0, L(less_4bytes)
    vstelm.w        vr0, a3, 0, 0
    vstelm.w        vr0, a4, -4, 0
    jr              ra


L(less_4bytes):
    srli.d          t0, a2, 1
    beqz            t0, L(less_2bytes)
    vstelm.h        vr0, a3, 0, 0
    vstelm.h        vr0, a4, -2, 0

    jr              ra
L(less_2bytes):
    beqz            a2, L(less_1bytes)
    st.b            a1, a3, 0
L(less_1bytes):
    jr              ra

L(long_bytes):
    xvst            xr0, a3, 0
    bstrins.d       a3, zero, 4, 0
    addi.d          a3, a3, 32
    sub.d           a2, a4, a3

    andi            t0, a2, 0xff
    beq             t0, a2, L(long_end)
    move            a2, t0
    sub.d           t0, a4, t0


L(loop_256):
    xvst            xr0, a3, 0
    xvst            xr0, a3, 32
    xvst            xr0, a3, 64
    xvst            xr0, a3, 96

    xvst            xr0, a3, 128
    xvst            xr0, a3, 160
    xvst            xr0, a3, 192
    xvst            xr0, a3, 224

    addi.d          a3, a3, 256
    bne             a3, t0, L(loop_256)
L(long_end):
    bltu            a2, t3, L(end_less_128)
    addi.d          a2, a2, -128

    xvst            xr0, a3, 0
    xvst            xr0, a3, 32
    xvst            xr0, a3, 64
    xvst            xr0, a3, 96


    addi.d          a3, a3, 128
L(end_less_128):
    bltu            a2, t2, L(end_less_64)
    addi.d          a2, a2, -64
    xvst            xr0, a3, 0

    xvst            xr0, a3, 32
    addi.d          a3, a3, 64
L(end_less_64):
    bltu            a2, t1, L(end_less_32)
    xvst            xr0, a3, 0

L(end_less_32):
    xvst            xr0, a4, -32
    jr              ra
END(MEMSET)

libc_hidden_builtin_def (MEMSET)
#endif
