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+// Copyright 2016 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"
+
+// See memclrNoHeapPointers Go doc for important implementation constraints.
+
+// void runtime·memclrNoHeapPointers(void*, uintptr)
+TEXT runtime·memclrNoHeapPointers(SB),NOSPLIT,$0-16
+ MOV ptr+0(FP), T1
+ MOV n+8(FP), T2
+ ADD T1, T2, T4
+
+ // If less than eight bytes, do one byte at a time.
+ SLTU $8, T2, T3
+ BNE T3, ZERO, outcheck
+
+ // Do one byte at a time until eight-aligned.
+ JMP aligncheck
+align:
+ MOVB ZERO, (T1)
+ ADD $1, T1
+aligncheck:
+ AND $7, T1, T3
+ BNE T3, ZERO, align
+
+ // Do eight bytes at a time as long as there is room.
+ ADD $-7, T4, T5
+ JMP wordscheck
+words:
+ MOV ZERO, (T1)
+ ADD $8, T1
+wordscheck:
+ SLTU T5, T1, T3
+ BNE T3, ZERO, words
+
+ JMP outcheck
+out:
+ MOVB ZERO, (T1)
+ ADD $1, T1
+outcheck:
+ BNE T1, T4, out
+
+done:
+ RET