mirror of
https://github.com/golang/go
synced 2024-11-06 05:26:11 -07:00
f2cde55cd6
The function signatures in the comments used a C-like style. Using Go function signatures is cleaner. Change-Id: I1a093ed8fe5df59f3697c613cf3fce58bba4f5c1 Reviewed-on: https://go-review.googlesource.com/113876 Run-TryBot: Michael Munday <mike.munday@ibm.com> TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
54 lines
984 B
ArmAsm
54 lines
984 B
ArmAsm
// Copyright 2013 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
#include "textflag.h"
|
|
|
|
// This could use MOVSQ, but we use MOVSL so that if an object ends in
|
|
// a 4 byte pointer, we copy it as a unit instead of byte by byte.
|
|
|
|
// func memmove(to, from unsafe.Pointer, n uintptr)
|
|
TEXT runtime·memmove(SB), NOSPLIT, $0-12
|
|
MOVL to+0(FP), DI
|
|
MOVL from+4(FP), SI
|
|
MOVL n+8(FP), BX
|
|
|
|
CMPL SI, DI
|
|
JLS back
|
|
|
|
forward:
|
|
MOVL BX, CX
|
|
SHRL $2, CX
|
|
ANDL $3, BX
|
|
REP; MOVSL
|
|
MOVL BX, CX
|
|
REP; MOVSB
|
|
RET
|
|
|
|
back:
|
|
MOVL SI, CX
|
|
ADDL BX, CX
|
|
CMPL CX, DI
|
|
JLS forward
|
|
|
|
ADDL BX, DI
|
|
ADDL BX, SI
|
|
STD
|
|
|
|
MOVL BX, CX
|
|
SHRL $2, CX
|
|
ANDL $3, BX
|
|
SUBL $4, DI
|
|
SUBL $4, SI
|
|
REP; MOVSL
|
|
ADDL $3, DI
|
|
ADDL $3, SI
|
|
MOVL BX, CX
|
|
REP; MOVSB
|
|
CLD
|
|
|
|
// Note: we copy only 4 bytes at a time so that the tail is at most
|
|
// 3 bytes. That guarantees that we aren't copying pointers with MOVSB.
|
|
// See issue 13160.
|
|
RET
|