strlen.s revision 9a70fc3be3b1e966bf78825cdb8d509963a6f0a1
/*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Copyright (c) 2002 Advanced Micro Devices, Inc.
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the
* following conditions are met:
*
* + Redistributions of source code must retain the above
* copyright notice, this list of conditions and the
* following disclaimer.
*
* + Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the
* following disclaimer in the documentation and/or other
* materials provided with the distribution.
*
* + Neither the name of Advanced Micro Devices, Inc. nor the
* names of its contributors may be used to endorse or
* promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS AS IS AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL ADVANCED MICRO DEVICES,
* INC. OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* It is licensee's responsibility to comply with any export
* regulations applicable in licensee's jurisdiction.
*/
.file "strlen.s"
#include "SYS.h"
#include "cache.h"
#define LABEL(s) .strlen/**/s
ENTRY(strlen) /* (const char *s) */
mov %rdi, %rsi
neg %rdi
LABEL(aligntry):
mov %rsi , %r8
and $7, %r8d
jz LABEL(alignafter)
LABEL(align): /* 8-byte align */
sub $8, %r8
.p2align 4
LABEL(alignloop):
cmpb $0, (%rsi)
je LABEL(exit)
inc %rsi
inc %r8
jnz LABEL(alignloop)
.p2align 4
LABEL(alignafter):
LABEL(56try):
LABEL(56): /* 56-byte */
mov (%rsi), %rax
mov $0xfefefefefefefeff, %rcx
LABEL(56loop):
mov %rcx, %r8
add %rax, %r8
jnc LABEL(tail)
xor %rax, %r8
or %rcx, %r8
inc %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
lea 8 (%rsi), %rsi
mov %rcx, %r8
add %rax, %r8
jnc LABEL(tail)
xor %rax, %r8
or %rcx, %r8
inc %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
lea 8 (%rsi), %rsi
mov %rcx, %r8
add %rax, %r8
jnc LABEL(tail)
xor %rax, %r8
or %rcx, %r8
inc %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
lea 8 (%rsi), %rsi
mov %rcx, %r8
add %rax, %r8
jnc LABEL(tail)
xor %rax, %r8
or %rcx, %r8
inc %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
lea 8 (%rsi), %rsi
mov %rcx, %r8
add %rax, %r8
jnc LABEL(tail)
xor %rax, %r8
or %rcx, %r8
inc %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
lea 8 (%rsi), %rsi
mov %rcx, %r8
add %rax, %r8
jnc LABEL(tail)
xor %rax, %r8
or %rcx, %r8
inc %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
lea 8 (%rsi), %rsi
mov %rcx, %r8
add %rax, %r8
jnc LABEL(tail)
xor %rax, %r8
or %rcx, %r8
inc %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
lea 8 (%rsi), %rsi
LABEL(56after):
LABEL(32): /* 32-byte */
mov _sref_(.amd64cache1), %r9
.p2align 4
LABEL(32loop):
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
sub $32, %r9
mov 8 (%rsi), %rax
lea 8 (%rsi), %rsi
jbe LABEL(32loop)
LABEL(32after):
LABEL(pretry):
LABEL(pre): /* 64-byte prefetch */
.p2align 4
LABEL(preloop):
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
mov 8 (%rsi), %rax
add $8, %rsi
mov %rcx, %r8
add %rax, %r8
sbb %rdx, %rdx
xor %rax, %r8
or %rcx, %r8
sub %rdx, %r8
jnz LABEL(tail)
prefetchnta 512 (%rsi) /* 3DNow: use prefetch */
mov 8 (%rsi), %rax
add $8, %rsi
jmp LABEL(preloop)
.p2align 4
LABEL(preafter):
LABEL(tailtry):
LABEL(tail): /* 4-byte tail */
LABEL(tailloop):
test %al, %al
jz LABEL(exit)
inc %rsi
test %ah, %ah
jz LABEL(exit)
inc %rsi
test $0x00ff0000, %eax
jz LABEL(exit)
inc %rsi
test $0xff000000, %eax
jz LABEL(exit)
inc %rsi
shr $32, %rax
jmp LABEL(tailloop)
LABEL(tailafter):
.p2align 4
LABEL(exit):
lea (%rdi, %rsi), %rax
ret
SET_SIZE(strlen)