// Copyright 2014 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" | |
// func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr) | |
TEXT runtime·memclrNoHeapPointers(SB), NOSPLIT, $0-8 | |
MOVL ptr+0(FP), DI | |
MOVL n+4(FP), BX | |
XORL AX, AX | |
tail: | |
TESTL BX, BX | |
JEQ _0 | |
CMPL BX, $2 | |
JBE _1or2 | |
CMPL BX, $4 | |
JB _3 | |
JE _4 | |
CMPL BX, $8 | |
JBE _5through8 | |
CMPL BX, $16 | |
JBE _9through16 | |
MOVL BX, CX | |
SHRL $2, CX | |
REP | |
STOSL | |
ANDL $3, BX | |
JNE tail | |
RET | |
_1or2: | |
MOVB AX, (DI) | |
MOVB AX, -1(DI)(BX*1) | |
RET | |
_0: | |
RET | |
_3: | |
MOVW AX, (DI) | |
MOVB AX, 2(DI) | |
RET | |
_4: | |
// We need a separate case for 4 to make sure we clear pointers atomically. | |
MOVL AX, (DI) | |
RET | |
_5through8: | |
MOVL AX, (DI) | |
MOVL AX, -4(DI)(BX*1) | |
RET | |
_9through16: | |
MOVL AX, (DI) | |
MOVL AX, 4(DI) | |
MOVL AX, -8(DI)(BX*1) | |
MOVL AX, -4(DI)(BX*1) | |
RET |