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authorRuss Cox <rsc@golang.org>2014-09-08 00:08:51 -0400
committerRuss Cox <rsc@golang.org>2014-09-08 00:08:51 -0400
commitc007ce824d9a4fccb148f9204e04c23ed2984b71 (patch)
tree7dcac257114ef5c446be5b7b68c27dea230b7c09 /src/runtime/memclr_amd64.s
parent220a6de47eced55956eb8af8d643d4f5b67fd634 (diff)
downloadgo-c007ce824d9a4fccb148f9204e04c23ed2984b71.tar.gz
go-c007ce824d9a4fccb148f9204e04c23ed2984b71.zip
build: move package sources from src/pkg to src
Preparation was in CL 134570043. This CL contains only the effect of 'hg mv src/pkg/* src'. For more about the move, see golang.org/s/go14nopkg.
Diffstat (limited to 'src/runtime/memclr_amd64.s')
-rw-r--r--src/runtime/memclr_amd64.s117
1 files changed, 117 insertions, 0 deletions
diff --git a/src/runtime/memclr_amd64.s b/src/runtime/memclr_amd64.s
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+++ b/src/runtime/memclr_amd64.s
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+// 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"
+
+// void runtime·memclr(void*, uintptr)
+TEXT runtime·memclr(SB), NOSPLIT, $0-16
+ MOVQ ptr+0(FP), DI
+ MOVQ n+8(FP), BX
+ XORQ AX, AX
+
+ // MOVOU seems always faster than REP STOSQ.
+clr_tail:
+ TESTQ BX, BX
+ JEQ clr_0
+ CMPQ BX, $2
+ JBE clr_1or2
+ CMPQ BX, $4
+ JBE clr_3or4
+ CMPQ BX, $8
+ JBE clr_5through8
+ CMPQ BX, $16
+ JBE clr_9through16
+ PXOR X0, X0
+ CMPQ BX, $32
+ JBE clr_17through32
+ CMPQ BX, $64
+ JBE clr_33through64
+ CMPQ BX, $128
+ JBE clr_65through128
+ CMPQ BX, $256
+ JBE clr_129through256
+ // TODO: use branch table and BSR to make this just a single dispatch
+ // TODO: for really big clears, use MOVNTDQ.
+
+clr_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)
+ SUBQ $256, BX
+ ADDQ $256, DI
+ CMPQ BX, $256
+ JAE clr_loop
+ JMP clr_tail
+
+clr_1or2:
+ MOVB AX, (DI)
+ MOVB AX, -1(DI)(BX*1)
+ RET
+clr_0:
+ RET
+clr_3or4:
+ MOVW AX, (DI)
+ MOVW AX, -2(DI)(BX*1)
+ RET
+clr_5through8:
+ MOVL AX, (DI)
+ MOVL AX, -4(DI)(BX*1)
+ RET
+clr_9through16:
+ MOVQ AX, (DI)
+ MOVQ AX, -8(DI)(BX*1)
+ RET
+clr_17through32:
+ MOVOU X0, (DI)
+ MOVOU X0, -16(DI)(BX*1)
+ RET
+clr_33through64:
+ MOVOU X0, (DI)
+ MOVOU X0, 16(DI)
+ MOVOU X0, -32(DI)(BX*1)
+ MOVOU X0, -16(DI)(BX*1)
+ RET
+clr_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
+clr_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