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/*
* ====================================================
* Copyright (C) 2007 by Ellips BV. All rights reserved.
*
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#include "x86_64mach.h"
.global SYM (memset)
SOTYPE_FUNCTION(memset)
SYM (memset):
movq rdi, r9 /* Save return value */
movq rsi, rax
movq rdx, rcx
cmpq $16, rdx
jb byte_set
movq rdi, r8 /* Align on quad word boundary */
andq $7, r8
jz quadword_aligned
movq $8, rcx
subq r8, rcx
subq rcx, rdx
rep stosb
movq rdx, rcx
quadword_aligned:
movabs $0x0101010101010101, r8
movzbl sil, eax
imul r8, rax
cmpq $256, rdx
jb quadword_set
shrq $7, rcx /* Store 128 bytes at a time with minimum cache polution */
.p2align 4
loop:
movntiq rax, (rdi)
movntiq rax, 8 (rdi)
movntiq rax, 16 (rdi)
movntiq rax, 24 (rdi)
movntiq rax, 32 (rdi)
movntiq rax, 40 (rdi)
movntiq rax, 48 (rdi)
movntiq rax, 56 (rdi)
movntiq rax, 64 (rdi)
movntiq rax, 72 (rdi)
movntiq rax, 80 (rdi)
movntiq rax, 88 (rdi)
movntiq rax, 96 (rdi)
movntiq rax, 104 (rdi)
movntiq rax, 112 (rdi)
movntiq rax, 120 (rdi)
leaq 128 (rdi), rdi
dec rcx
jnz loop
sfence
movq rdx, rcx
andq $127, rcx
rep stosb
movq r9, rax
ret
byte_set:
rep stosb
movq r9, rax
ret
quadword_set:
shrq $3, rcx
.p2align 4
rep stosq
movq rdx, rcx
andq $7, rcx
rep stosb /* Store the remaining bytes */
movq r9, rax
ret
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