| // 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. | |
| // +build !plan9 | |
| #include "textflag.h" | |
| // NOTE: Windows externalthreadhandler expects memclr to preserve DX. | |
| // 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 | |
| // MOVOU seems always faster than REP STOSL. | |
| tail: | |
| // BSR+branch table make almost all memmove/memclr benchmarks worse. Not worth doing. | |
| 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 | |
| CMPB runtime·support_sse2(SB), $1 | |
| JNE nosse2 | |
| PXOR X0, X0 | |
| CMPL BX, $32 | |
| JBE _17through32 | |
| CMPL BX, $64 | |
| JBE _33through64 | |
| CMPL BX, $128 | |
| JBE _65through128 | |
| CMPL BX, $256 | |
| JBE _129through256 | |
| loop: | |
| MOVOU X0, 0(DI) | |
| MOVOU X0, 16(DI) | |
| MOVOU X0, 32(DI) | |
| MOVOU X0, 48(DI) | |
| MOVOU X0, 64(DI) | |
| MOVOU X0, 80(DI) | |
| MOVOU X0, 96(DI) | |
| MOVOU X0, 112(DI) | |
| MOVOU X0, 128(DI) | |
| MOVOU X0, 144(DI) | |
| MOVOU X0, 160(DI) | |
| MOVOU X0, 176(DI) | |
| MOVOU X0, 192(DI) | |
| MOVOU X0, 208(DI) | |
| MOVOU X0, 224(DI) | |
| MOVOU X0, 240(DI) | |
| SUBL $256, BX | |
| ADDL $256, DI | |
| CMPL BX, $256 | |
| JAE loop | |
| JMP tail | |
| _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 | |
| _17through32: | |
| MOVOU X0, (DI) | |
| MOVOU X0, -16(DI)(BX*1) | |
| RET | |
| _33through64: | |
| MOVOU X0, (DI) | |
| MOVOU X0, 16(DI) | |
| MOVOU X0, -32(DI)(BX*1) | |
| MOVOU X0, -16(DI)(BX*1) | |
| RET | |
| _65through128: | |
| MOVOU X0, (DI) | |
| MOVOU X0, 16(DI) | |
| MOVOU X0, 32(DI) | |
| MOVOU X0, 48(DI) | |
| MOVOU X0, -64(DI)(BX*1) | |
| MOVOU X0, -48(DI)(BX*1) | |
| MOVOU X0, -32(DI)(BX*1) | |
| MOVOU X0, -16(DI)(BX*1) | |
| RET | |
| _129through256: | |
| MOVOU X0, (DI) | |
| MOVOU X0, 16(DI) | |
| MOVOU X0, 32(DI) | |
| MOVOU X0, 48(DI) | |
| MOVOU X0, 64(DI) | |
| MOVOU X0, 80(DI) | |
| MOVOU X0, 96(DI) | |
| MOVOU X0, 112(DI) | |
| MOVOU X0, -128(DI)(BX*1) | |
| MOVOU X0, -112(DI)(BX*1) | |
| MOVOU X0, -96(DI)(BX*1) | |
| MOVOU X0, -80(DI)(BX*1) | |
| MOVOU X0, -64(DI)(BX*1) | |
| MOVOU X0, -48(DI)(BX*1) | |
| MOVOU X0, -32(DI)(BX*1) | |
| MOVOU X0, -16(DI)(BX*1) | |
| RET | |
| nosse2: | |
| MOVL BX, CX | |
| SHRL $2, CX | |
| REP | |
| STOSL | |
| ANDL $3, BX | |
| JNE tail | |
| RET |