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|
/*
Optimized memcpy for x86-64.
Copyright (C) 2007 Free Software Foundation, Inc.
Contributed by Evandro Menezes <evandro.menezes@amd.com>, 2007.
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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.
*/
#include <sysdep.h>
#include "asm-syntax.h"
/* Stack slots in the red-zone. */
#ifdef USE_AS_MEMPCPY
# define RETVAL (0)
#else
# define RETVAL (-8)
#endif
#define SAVE0 (RETVAL - 8)
#define SAVE1 (SAVE0 - 8)
#define SAVE2 (SAVE1 - 8)
#define SAVE3 (SAVE2 - 8)
.text
#if defined PIC && !defined NOT_IN_libc
ENTRY (__memcpy_chk)
cmpq %rdx, %rcx
jb HIDDEN_JUMPTARGET (__chk_fail)
END (__memcpy_chk)
#endif
ENTRY(memcpy) /* (void *, const void*, size_t) */
/* Handle tiny blocks. */
L(1try): /* up to 32B */
cmpq $32, %rdx
#ifndef USE_AS_MEMPCPY
movq %rdi, %rax /* save return value */
#endif
jae L(1after)
L(1): /* 1-byte once */
testb $1, %dl
jz L(1a)
movzbl (%rsi), %ecx
movb %cl, (%rdi)
incq %rsi
incq %rdi
.p2align 4,, 4
L(1a): /* 2-byte once */
testb $2, %dl
jz L(1b)
movzwl (%rsi), %ecx
movw %cx, (%rdi)
addq $2, %rsi
addq $2, %rdi
.p2align 4,, 4
L(1b): /* 4-byte once */
testb $4, %dl
jz L(1c)
movl (%rsi), %ecx
movl %ecx, (%rdi)
addq $4, %rsi
addq $4, %rdi
.p2align 4,, 4
L(1c): /* 8-byte once */
testb $8, %dl
jz L(1d)
movq (%rsi), %rcx
movq %rcx, (%rdi)
addq $8, %rsi
addq $8, %rdi
.p2align 4,, 4
L(1d): /* 16-byte loop */
andl $0xf0, %edx
jz L(exit)
.p2align 4
L(1loop):
movq (%rsi), %rcx
movq 8(%rsi), %r8
movq %rcx, (%rdi)
movq %r8, 8(%rdi)
subl $16, %edx
leaq 16(%rsi), %rsi
leaq 16(%rdi), %rdi
jnz L(1loop)
.p2align 4,, 4
L(exit): /* exit */
#ifdef USE_AS_MEMPCPY
movq %rdi, %rax /* return value */
#else
rep
#endif
retq
.p2align 4
L(1after):
#ifndef USE_AS_MEMPCPY
movq %rax, RETVAL(%rsp) /* save return value */
#endif
/* Align to the natural word size. */
L(aligntry):
movl %esi, %ecx /* align by source */
andl $7, %ecx
jz L(alignafter) /* already aligned */
L(align): /* align */
leaq -8(%rcx, %rdx), %rdx /* calculate remaining bytes */
subl $8, %ecx
.p2align 4
L(alignloop): /* 1-byte alignment loop */
movzbl (%rsi), %eax
movb %al, (%rdi)
incl %ecx
leaq 1(%rsi), %rsi
leaq 1(%rdi), %rdi
jnz L(alignloop)
.p2align 4
L(alignafter):
/* Handle mid-sized blocks. */
L(32try): /* up to 1KB */
cmpq $1024, %rdx
ja L(32after)
L(32): /* 32-byte loop */
movl %edx, %ecx
shrl $5, %ecx
jz L(32skip)
.p2align 4
L(32loop):
decl %ecx
movq (%rsi), %rax
movq 8(%rsi), %r8
movq 16(%rsi), %r9
movq 24(%rsi), %r10
movq %rax, (%rdi)
movq %r8, 8(%rdi)
movq %r9, 16(%rdi)
movq %r10, 24(%rdi)
leaq 32(%rsi), %rsi
leaq 32(%rdi), %rdi
jz L(32skip) /* help out smaller blocks */
decl %ecx
movq (%rsi), %rax
movq 8(%rsi), %r8
movq 16(%rsi), %r9
movq 24(%rsi), %r10
movq %rax, (%rdi)
movq %r8, 8(%rdi)
movq %r9, 16(%rdi)
movq %r10, 24(%rdi)
leaq 32(%rsi), %rsi
leaq 32(%rdi), %rdi
jnz L(32loop)
.p2align 4
L(32skip):
andl $31, %edx /* check for left overs */
#ifdef USE_AS_MEMPCPY
jnz L(1)
movq %rdi, %rax
#else
movq RETVAL(%rsp), %rax
jnz L(1)
rep
#endif
retq /* exit */
.p2align 4
L(32after):
/*
In order to minimize code-size in RTLD, algorithms specific for
larger blocks are excluded when building for RTLD.
*/
/* Handle blocks smaller than 1/2 L1. */
L(fasttry): /* first 1/2 L1 */
#ifndef NOT_IN_libc /* only up to this algorithm outside of libc.so */
movq __x86_64_data_cache_size_half(%rip), %r11
cmpq %rdx, %r11 /* calculate the smaller of */
cmovaq %rdx, %r11 /* remaining bytes and 1/2 L1 */
#endif
L(fast): /* good ol' MOVS */
#ifndef NOT_IN_libc
movq %r11, %rcx
andq $-8, %r11
#else
movq %rdx, %rcx
#endif
shrq $3, %rcx
jz L(fastskip)
rep
movsq
.p2align 4,, 4
L(fastskip):
#ifndef NOT_IN_libc
subq %r11, %rdx /* check for more */
testq $-8, %rdx
jnz L(fastafter)
#endif
andl $7, %edx /* check for left overs */
#ifdef USE_AS_MEMPCPY
jnz L(1)
movq %rdi, %rax
#else
movq RETVAL(%rsp), %rax
jnz L(1)
rep
#endif
retq /* exit */
#ifndef NOT_IN_libc /* none of the algorithms below for RTLD */
.p2align 4
L(fastafter):
/* Handle large blocks smaller than 1/2 L2. */
L(pretry): /* first 1/2 L2 */
movq __x86_64_shared_cache_size_half (%rip), %r8
cmpq %rdx, %r8 /* calculate the lesser of */
cmovaq %rdx, %r8 /* remaining bytes and 1/2 L2 */
L(pre): /* 64-byte with prefetching */
movq %r8, %rcx
andq $-64, %r8
shrq $6, %rcx
jz L(preskip)
movq %r14, SAVE0(%rsp)
cfi_rel_offset (%r14, SAVE0)
movq %r13, SAVE1(%rsp)
cfi_rel_offset (%r13, SAVE1)
movq %r12, SAVE2(%rsp)
cfi_rel_offset (%r12, SAVE2)
movq %rbx, SAVE3(%rsp)
cfi_rel_offset (%rbx, SAVE3)
cmpl $0, __x86_64_prefetchw(%rip)
jz L(preloop) /* check if PREFETCHW OK */
.p2align 4
/* ... when PREFETCHW is available (less cache-probe traffic in MP systems). */
L(prewloop): /* cache-line in state M */
decq %rcx
movq (%rsi), %rax
movq 8 (%rsi), %rbx
movq 16 (%rsi), %r9
movq 24 (%rsi), %r10
movq 32 (%rsi), %r11
movq 40 (%rsi), %r12
movq 48 (%rsi), %r13
movq 56 (%rsi), %r14
prefetcht0 0 + 896 (%rsi)
prefetcht0 64 + 896 (%rsi)
movq %rax, (%rdi)
movq %rbx, 8(%rdi)
movq %r9, 16(%rdi)
movq %r10, 24(%rdi)
movq %r11, 32(%rdi)
movq %r12, 40(%rdi)
movq %r13, 48(%rdi)
movq %r14, 56(%rdi)
leaq 64(%rsi), %rsi
leaq 64(%rdi), %rdi
jz L(prebail)
decq %rcx
movq (%rsi), %rax
movq 8(%rsi), %rbx
movq 16(%rsi), %r9
movq 24(%rsi), %r10
movq 32(%rsi), %r11
movq 40(%rsi), %r12
movq 48(%rsi), %r13
movq 56(%rsi), %r14
movq %rax, (%rdi)
movq %rbx, 8(%rdi)
movq %r9, 16(%rdi)
movq %r10, 24(%rdi)
movq %r11, 32(%rdi)
movq %r12, 40(%rdi)
movq %r13, 48(%rdi)
movq %r14, 56(%rdi)
prefetchw 896 - 64(%rdi)
prefetchw 896 - 0(%rdi)
leaq 64(%rsi), %rsi
leaq 64(%rdi), %rdi
jnz L(prewloop)
jmp L(prebail)
.p2align 4
/* ... when PREFETCHW is not available. */
L(preloop): /* cache-line in state E */
decq %rcx
movq (%rsi), %rax
movq 8(%rsi), %rbx
movq 16(%rsi), %r9
movq 24(%rsi), %r10
movq 32(%rsi), %r11
movq 40(%rsi), %r12
movq 48(%rsi), %r13
movq 56(%rsi), %r14
prefetcht0 896 + 0(%rsi)
prefetcht0 896 + 64(%rsi)
movq %rax, (%rdi)
movq %rbx, 8(%rdi)
movq %r9, 16(%rdi)
movq %r10, 24(%rdi)
movq %r11, 32(%rdi)
movq %r12, 40(%rdi)
movq %r13, 48(%rdi)
movq %r14, 56(%rdi)
leaq 64 (%rsi), %rsi
leaq 64 (%rdi), %rdi
jz L(prebail)
decq %rcx
movq (%rsi), %rax
movq 8(%rsi), %rbx
movq 16(%rsi), %r9
movq 24(%rsi), %r10
movq 32(%rsi), %r11
movq 40(%rsi), %r12
movq 48(%rsi), %r13
movq 56(%rsi), %r14
prefetcht0 896 - 64(%rdi)
prefetcht0 896 - 0(%rdi)
movq %rax, (%rdi)
movq %rbx, 8(%rdi)
movq %r9, 16(%rdi)
movq %r10, 24(%rdi)
movq %r11, 32(%rdi)
movq %r12, 40(%rdi)
movq %r13, 48(%rdi)
movq %r14, 56(%rdi)
leaq 64(%rsi), %rsi
leaq 64(%rdi), %rdi
jnz L(preloop)
L(prebail):
movq SAVE3(%rsp), %rbx
cfi_restore (%rbx)
movq SAVE2(%rsp), %r12
cfi_restore (%r12)
movq SAVE1(%rsp), %r13
cfi_restore (%r13)
movq SAVE0(%rsp), %r14
cfi_restore (%r14)
/* .p2align 4 */
L(preskip):
subq %r8, %rdx /* check for more */
testq $-64, %rdx
jnz L(preafter)
andl $63, %edx /* check for left overs */
#ifdef USE_AS_MEMPCPY
jnz L(1)
movq %rdi, %rax
#else
movq RETVAL(%rsp), %rax
jnz L(1)
rep
#endif
retq /* exit */
.p2align 4
L(preafter):
/* Handle huge blocks. */
L(NTtry):
L(NT): /* non-temporal 128-byte */
movq %rdx, %rcx
shrq $7, %rcx
jz L(NTskip)
movq %r14, SAVE0(%rsp)
cfi_rel_offset (%r14, SAVE0)
movq %r13, SAVE1(%rsp)
cfi_rel_offset (%r13, SAVE1)
movq %r12, SAVE2(%rsp)
cfi_rel_offset (%r12, SAVE2)
.p2align 4
L(NTloop):
prefetchnta 768(%rsi)
prefetchnta 832(%rsi)
decq %rcx
movq (%rsi), %rax
movq 8(%rsi), %r8
movq 16(%rsi), %r9
movq 24(%rsi), %r10
movq 32(%rsi), %r11
movq 40(%rsi), %r12
movq 48(%rsi), %r13
movq 56(%rsi), %r14
movntiq %rax, (%rdi)
movntiq %r8, 8(%rdi)
movntiq %r9, 16(%rdi)
movntiq %r10, 24(%rdi)
movntiq %r11, 32(%rdi)
movntiq %r12, 40(%rdi)
movntiq %r13, 48(%rdi)
movntiq %r14, 56(%rdi)
movq 64(%rsi), %rax
movq 72(%rsi), %r8
movq 80(%rsi), %r9
movq 88(%rsi), %r10
movq 96(%rsi), %r11
movq 104(%rsi), %r12
movq 112(%rsi), %r13
movq 120(%rsi), %r14
movntiq %rax, 64(%rdi)
movntiq %r8, 72(%rdi)
movntiq %r9, 80(%rdi)
movntiq %r10, 88(%rdi)
movntiq %r11, 96(%rdi)
movntiq %r12, 104(%rdi)
movntiq %r13, 112(%rdi)
movntiq %r14, 120(%rdi)
leaq 128(%rsi), %rsi
leaq 128(%rdi), %rdi
jnz L(NTloop)
sfence /* serialize memory stores */
movq SAVE2(%rsp), %r12
cfi_restore (%r12)
movq SAVE1(%rsp), %r13
cfi_restore (%r13)
movq SAVE0(%rsp), %r14
cfi_restore (%r14)
L(NTskip):
andl $127, %edx /* check for left overs */
#ifdef USE_AS_MEMPCPY
jnz L(1)
movq %rdi, %rax
#else
movq RETVAL(%rsp), %rax
jnz L(1)
rep
#endif
retq /* exit */
#endif /* !NOT_IN_libc */
END(memcpy)
#ifndef USE_AS_MEMPCPY
libc_hidden_builtin_def (memcpy)
#endif
|
