mirror of https://github.com/golang/go.git
24 lines
457 B
ArmAsm
24 lines
457 B
ArmAsm
// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// func cas(val *int32, old, new int32) bool
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// Atomically:
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// if *val == old {
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// *val = new;
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// return true;
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// }else
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// return false;
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TEXT sync·cas(SB), 7, $0
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MOVQ 8(SP), BX
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MOVL 16(SP), AX
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MOVL 20(SP), CX
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LOCK
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CMPXCHGL CX, 0(BX)
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JZ ok
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MOVL $0, 24(SP)
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RET
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ok:
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MOVL $1, 24(SP)
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RET
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