| Keith Randall | da7cf0b | 2014-02-06 17:43:22 -0800 | [diff] [blame] | 1 | // Copyright 2014 The Go Authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style |
| 3 | // license that can be found in the LICENSE file. |
| 4 | |
| Anthony Martin | 8303a13 | 2014-03-12 18:12:25 -0700 | [diff] [blame] | 5 | // +build !plan9 |
| 6 | |
| Russ Cox | cb040d5 | 2014-09-04 23:05:18 -0400 | [diff] [blame] | 7 | #include "textflag.h" |
| Keith Randall | da7cf0b | 2014-02-06 17:43:22 -0800 | [diff] [blame] | 8 | |
| Russ Cox | ee6c6d9 | 2014-09-09 17:12:05 -0400 | [diff] [blame^] | 9 | // NOTE: Windows externalthreadhandler expects memclr to preserve DX. |
| 10 | |
| Keith Randall | da7cf0b | 2014-02-06 17:43:22 -0800 | [diff] [blame] | 11 | // void runtime·memclr(void*, uintptr) |
| 12 | TEXT runtime·memclr(SB), NOSPLIT, $0-8 |
| 13 | MOVL ptr+0(FP), DI |
| 14 | MOVL n+4(FP), BX |
| 15 | XORL AX, AX |
| 16 | |
| 17 | // MOVOU seems always faster than REP STOSL. |
| 18 | clr_tail: |
| 19 | TESTL BX, BX |
| 20 | JEQ clr_0 |
| 21 | CMPL BX, $2 |
| 22 | JBE clr_1or2 |
| 23 | CMPL BX, $4 |
| 24 | JBE clr_3or4 |
| 25 | CMPL BX, $8 |
| 26 | JBE clr_5through8 |
| 27 | CMPL BX, $16 |
| 28 | JBE clr_9through16 |
| 29 | TESTL $0x4000000, runtime·cpuid_edx(SB) // check for sse2 |
| 30 | JEQ nosse2 |
| 31 | PXOR X0, X0 |
| 32 | CMPL BX, $32 |
| 33 | JBE clr_17through32 |
| 34 | CMPL BX, $64 |
| 35 | JBE clr_33through64 |
| 36 | CMPL BX, $128 |
| 37 | JBE clr_65through128 |
| 38 | CMPL BX, $256 |
| 39 | JBE clr_129through256 |
| 40 | // TODO: use branch table and BSR to make this just a single dispatch |
| 41 | |
| 42 | clr_loop: |
| 43 | MOVOU X0, 0(DI) |
| 44 | MOVOU X0, 16(DI) |
| 45 | MOVOU X0, 32(DI) |
| 46 | MOVOU X0, 48(DI) |
| 47 | MOVOU X0, 64(DI) |
| 48 | MOVOU X0, 80(DI) |
| 49 | MOVOU X0, 96(DI) |
| 50 | MOVOU X0, 112(DI) |
| 51 | MOVOU X0, 128(DI) |
| 52 | MOVOU X0, 144(DI) |
| 53 | MOVOU X0, 160(DI) |
| 54 | MOVOU X0, 176(DI) |
| 55 | MOVOU X0, 192(DI) |
| 56 | MOVOU X0, 208(DI) |
| 57 | MOVOU X0, 224(DI) |
| 58 | MOVOU X0, 240(DI) |
| 59 | SUBL $256, BX |
| 60 | ADDL $256, DI |
| 61 | CMPL BX, $256 |
| 62 | JAE clr_loop |
| 63 | JMP clr_tail |
| 64 | |
| 65 | clr_1or2: |
| 66 | MOVB AX, (DI) |
| 67 | MOVB AX, -1(DI)(BX*1) |
| Josh Bleecher Snyder | bc9e160 | 2014-08-01 06:21:08 -0700 | [diff] [blame] | 68 | RET |
| Keith Randall | da7cf0b | 2014-02-06 17:43:22 -0800 | [diff] [blame] | 69 | clr_0: |
| 70 | RET |
| 71 | clr_3or4: |
| 72 | MOVW AX, (DI) |
| 73 | MOVW AX, -2(DI)(BX*1) |
| 74 | RET |
| 75 | clr_5through8: |
| 76 | MOVL AX, (DI) |
| 77 | MOVL AX, -4(DI)(BX*1) |
| 78 | RET |
| 79 | clr_9through16: |
| 80 | MOVL AX, (DI) |
| 81 | MOVL AX, 4(DI) |
| 82 | MOVL AX, -8(DI)(BX*1) |
| 83 | MOVL AX, -4(DI)(BX*1) |
| 84 | RET |
| 85 | clr_17through32: |
| 86 | MOVOU X0, (DI) |
| 87 | MOVOU X0, -16(DI)(BX*1) |
| 88 | RET |
| 89 | clr_33through64: |
| 90 | MOVOU X0, (DI) |
| 91 | MOVOU X0, 16(DI) |
| 92 | MOVOU X0, -32(DI)(BX*1) |
| 93 | MOVOU X0, -16(DI)(BX*1) |
| 94 | RET |
| 95 | clr_65through128: |
| 96 | MOVOU X0, (DI) |
| 97 | MOVOU X0, 16(DI) |
| 98 | MOVOU X0, 32(DI) |
| 99 | MOVOU X0, 48(DI) |
| 100 | MOVOU X0, -64(DI)(BX*1) |
| 101 | MOVOU X0, -48(DI)(BX*1) |
| 102 | MOVOU X0, -32(DI)(BX*1) |
| 103 | MOVOU X0, -16(DI)(BX*1) |
| 104 | RET |
| 105 | clr_129through256: |
| 106 | MOVOU X0, (DI) |
| 107 | MOVOU X0, 16(DI) |
| 108 | MOVOU X0, 32(DI) |
| 109 | MOVOU X0, 48(DI) |
| 110 | MOVOU X0, 64(DI) |
| 111 | MOVOU X0, 80(DI) |
| 112 | MOVOU X0, 96(DI) |
| 113 | MOVOU X0, 112(DI) |
| 114 | MOVOU X0, -128(DI)(BX*1) |
| 115 | MOVOU X0, -112(DI)(BX*1) |
| 116 | MOVOU X0, -96(DI)(BX*1) |
| 117 | MOVOU X0, -80(DI)(BX*1) |
| 118 | MOVOU X0, -64(DI)(BX*1) |
| 119 | MOVOU X0, -48(DI)(BX*1) |
| 120 | MOVOU X0, -32(DI)(BX*1) |
| 121 | MOVOU X0, -16(DI)(BX*1) |
| 122 | RET |
| 123 | nosse2: |
| 124 | MOVL BX, CX |
| 125 | SHRL $2, CX |
| 126 | REP |
| 127 | STOSL |
| 128 | ANDL $3, BX |
| 129 | JNE clr_tail |
| 130 | RET |
