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40 lines
754 B
ArmAsm
40 lines
754 B
ArmAsm
// Copyright 2014 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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// +build !gccgo
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#include "textflag.h"
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TEXT cas<>(SB),NOSPLIT,$0
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MOVW $0xffff0fc0, R15 // R15 is PC
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TEXT ·RewindAndSetgid(SB),NOSPLIT,$-4-0
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// Save link register
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MOVW R14, R4
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// Rewind stack pointer so anything that happens on the stack
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// will clobber the test pattern created by the caller
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ADD $(1024 * 8), R13
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// Ask signaller to setgid
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MOVW $·Baton(SB), R2
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storeloop:
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MOVW 0(R2), R0
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MOVW $1, R1
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BL cas<>(SB)
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BCC storeloop
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// Wait for setgid completion
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loop:
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MOVW $0, R0
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MOVW $0, R1
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BL cas<>(SB)
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BCC loop
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// Restore stack
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SUB $(1024 * 8), R13
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MOVW R4, R14
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RET
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