Detab

[mirror_edk2.git] / MdePkg / Library / BaseMemoryLibOptDxe / X64 / SetMem.S

#------------------------------------------------------------------------------\r
#\r
# Copyright (c) 2006, Intel Corporation\r
# All rights reserved. This program and the accompanying materials\r
# are licensed and made available under the terms and conditions of the BSD License\r
# which accompanies this distribution.  The full text of the license may be found at\r
# http://opensource.org/licenses/bsd-license.php\r
#\r
# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
#\r
# Module Name:\r
#\r
#   SetMem.S\r
#\r
# Abstract:\r
#\r
#   SetMem function\r
#\r
# Notes:\r
#\r
#------------------------------------------------------------------------------\r
#------------------------------------------------------------------------------\r
#  VOID *\r
#  EFIAPI\r
#  InternalMemSetMem (\r
#    IN VOID   *Buffer,\r
#    IN UINTN  Count,\r
#    IN UINT8  Value\r
#    )\r
#------------------------------------------------------------------------------\r
.intel_syntax noprefix\r
.globl ASM_PFX(InternalMemSetMem)\r
ASM_PFX(InternalMemZeroMem):\r
    push    rdi\r
    push    rbx\r
    push    rcx         # push Buffer\r
    mov     rax, r8     # rax = Value\r
    and     rax, 0xff   # rax = lower 8 bits of r8, upper 56 bits are 0\r
    mov     ah,  al     # ah  = al\r
    mov     bx,  ax     # bx  = ax\r
    shl     rax, 0x10   # rax = ax << 16\r
    mov     ax,  bx     # ax  = bx\r
    mov     rbx, rax    # ebx = eax\r
    shl     rax, 0x20   # rax = rax << 32\r
    or      rax, rbx    # eax = ebx\r
    mov     rdi, rcx    # rdi = Buffer\r
    mov     rcx, rdx    # rcx = Count\r
    shr     rcx, 3      # rcx = rcx / 8\r
    cld\r
    rep     stosq \r
    mov     rcx, rdx    # rcx = rdx\r
    and     rcx, 7      # rcx = rcx & 7\r
    rep     stosb \r
    pop     rax         # rax = Buffer\r
    pop     rbx\r
    pop     rdi\r
    ret\r