| /* memset/bzero -- set memory area to CH/0 |
| Optimized version for x86-64. |
| Copyright (C) 2002-2014 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> |
| |
| .text |
| #if !defined NOT_IN_libc |
| ENTRY(__bzero) |
| movq %rdi, %rax /* Set return value. */ |
| movq %rsi, %rdx /* Set n. */ |
| pxor %xmm8, %xmm8 |
| jmp L(entry_from_bzero) |
| END(__bzero) |
| weak_alias (__bzero, bzero) |
| |
| /* Like memset but takes additional parameter with return value. */ |
| ENTRY(__memset_tail) |
| movq %rcx, %rax /* Set return value. */ |
| |
| movd %esi, %xmm8 |
| punpcklbw %xmm8, %xmm8 |
| punpcklwd %xmm8, %xmm8 |
| pshufd $0, %xmm8, %xmm8 |
| |
| jmp L(entry_from_bzero) |
| END(__memset_tail) |
| #endif |
| |
| #if defined PIC && !defined NOT_IN_libc |
| ENTRY_CHK (__memset_chk) |
| cmpq %rdx, %rcx |
| jb HIDDEN_JUMPTARGET (__chk_fail) |
| END_CHK (__memset_chk) |
| #endif |
| |
| ENTRY (memset) |
| movd %esi, %xmm8 |
| movq %rdi, %rax |
| punpcklbw %xmm8, %xmm8 |
| punpcklwd %xmm8, %xmm8 |
| pshufd $0, %xmm8, %xmm8 |
| L(entry_from_bzero): |
| cmpq $64, %rdx |
| ja L(loop_start) |
| cmpq $16, %rdx |
| jbe L(less_16_bytes) |
| cmpq $32, %rdx |
| movdqu %xmm8, (%rdi) |
| movdqu %xmm8, -16(%rdi,%rdx) |
| ja L(between_32_64_bytes) |
| L(return): |
| rep |
| ret |
| .p2align 4 |
| L(between_32_64_bytes): |
| movdqu %xmm8, 16(%rdi) |
| movdqu %xmm8, -32(%rdi,%rdx) |
| ret |
| .p2align 4 |
| L(loop_start): |
| leaq 64(%rdi), %rcx |
| movdqu %xmm8, (%rdi) |
| andq $-64, %rcx |
| movdqu %xmm8, -16(%rdi,%rdx) |
| movdqu %xmm8, 16(%rdi) |
| movdqu %xmm8, -32(%rdi,%rdx) |
| movdqu %xmm8, 32(%rdi) |
| movdqu %xmm8, -48(%rdi,%rdx) |
| movdqu %xmm8, 48(%rdi) |
| movdqu %xmm8, -64(%rdi,%rdx) |
| addq %rdi, %rdx |
| andq $-64, %rdx |
| cmpq %rdx, %rcx |
| je L(return) |
| .p2align 4 |
| L(loop): |
| movdqa %xmm8, (%rcx) |
| movdqa %xmm8, 16(%rcx) |
| movdqa %xmm8, 32(%rcx) |
| movdqa %xmm8, 48(%rcx) |
| addq $64, %rcx |
| cmpq %rcx, %rdx |
| jne L(loop) |
| rep |
| ret |
| L(less_16_bytes): |
| movq %xmm8, %rcx |
| testb $24, %dl |
| jne L(between8_16bytes) |
| testb $4, %dl |
| jne L(between4_7bytes) |
| testb $1, %dl |
| je L(odd_byte) |
| movb %cl, (%rdi) |
| L(odd_byte): |
| testb $2, %dl |
| je L(return) |
| movw %cx, -2(%rax,%rdx) |
| ret |
| L(between4_7bytes): |
| movl %ecx, (%rdi) |
| movl %ecx, -4(%rdi,%rdx) |
| ret |
| L(between8_16bytes): |
| movq %rcx, (%rdi) |
| movq %rcx, -8(%rdi,%rdx) |
| ret |
| |
| END (memset) |
| libc_hidden_builtin_def (memset) |
| |
| #if defined PIC && !defined NOT_IN_libc && !defined USE_MULTIARCH |
| strong_alias (__memset_chk, __memset_zero_constant_len_parameter) |
| .section .gnu.warning.__memset_zero_constant_len_parameter |
| .string "memset used with constant zero length parameter; this could be due to transposed parameters" |
| #endif |
