1 files changed, 48 insertions, 0 deletions
diff --git a/src/pkg/runtime/memclr_plan9_amd64.s b/src/pkg/runtime/memclr_plan9_amd64.s
new file mode 100644
index 000000000..6b33054f5
--- /dev/null
+++ b/src/pkg/runtime/memclr_plan9_amd64.s
@@ -0,0 +1,48 @@
+// 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 "../../cmd/ld/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
+
+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
+	MOVQ	BX, CX
+	SHRQ	$2, CX
+	REP
+	STOSQ
+	ANDQ	$3, BX
+	JNE	clr_tail
+	RET
+
+clr_1or2:
+	MOVB	AX, (DI)
+	MOVB	AX, -1(DI)(BX*1)
+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