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/* $NetBSD: __sigtramp2.S,v 1.5 2021/11/27 10:00:01 skrll Exp $ */
/*-
* Copyright (c) 2002 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "SYS.h"
#include "assym.h"
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: __sigtramp2.S,v 1.5 2021/11/27 10:00:01 skrll Exp $")
#endif /* LIBC_SCCS && !lint */
/*
* On entry to user space, stack and registers look like:
*
* r3 signal number
* r4 pointer to siginfo structure
* r5 pointer to ucontext structure
* r30 pointer to ucontext structure
* srr0 address of handler
* lr address of this trampoline
*
* We use r30 as the CFA base register since it's been conveniently set up
* for us that way. The DWARF register numbers used in the .eh_frame are:
*
* 0 - 31 GPRs
* 32 - 63 FPRs
* 65 LR
* 66 CTR
* 68-75 CRs
* 76 XER
* 77 - 108 AltiVec regs
* 99 signal trampoline return address
* 109 VRSAVE
* 110 VCSR
*
* N.B. Only one CR slot is used (CR2) in the SVR4 ABI.
*/
#define DWARF_LR_REG 65
#define DWARF_CTR_REG 66
#define DWARF_CR2_REG 70
#define DWARF_XER_REG 76
#define DWARF_SIGRETURN_REG 99
#define CFI_OFFSET_DWARF_REG(d, r) .cfi_offset d, r * 4
#define CFI_OFFSET(r) CFI_OFFSET_DWARF_REG(r, r)
.text
.cfi_startproc simple
.cfi_signal_frame
.cfi_def_cfa _REG_R30, UC_GREGS
CFI_OFFSET(_REG_R0)
CFI_OFFSET(_REG_R1)
CFI_OFFSET(_REG_R2)
CFI_OFFSET(_REG_R3)
CFI_OFFSET(_REG_R4)
CFI_OFFSET(_REG_R5)
CFI_OFFSET(_REG_R6)
CFI_OFFSET(_REG_R7)
CFI_OFFSET(_REG_R8)
CFI_OFFSET(_REG_R9)
CFI_OFFSET(_REG_R10)
CFI_OFFSET(_REG_R11)
CFI_OFFSET(_REG_R12)
CFI_OFFSET(_REG_R13)
CFI_OFFSET(_REG_R14)
CFI_OFFSET(_REG_R15)
CFI_OFFSET(_REG_R16)
CFI_OFFSET(_REG_R17)
CFI_OFFSET(_REG_R18)
CFI_OFFSET(_REG_R19)
CFI_OFFSET(_REG_R20)
CFI_OFFSET(_REG_R21)
CFI_OFFSET(_REG_R22)
CFI_OFFSET(_REG_R23)
CFI_OFFSET(_REG_R24)
CFI_OFFSET(_REG_R25)
CFI_OFFSET(_REG_R26)
CFI_OFFSET(_REG_R27)
CFI_OFFSET(_REG_R28)
CFI_OFFSET(_REG_R29)
CFI_OFFSET(_REG_R30)
CFI_OFFSET(_REG_R31)
CFI_OFFSET_DWARF_REG(DWARF_CR2_REG, _REG_CR)
CFI_OFFSET_DWARF_REG(DWARF_LR_REG, _REG_LR)
CFI_OFFSET_DWARF_REG(DWARF_CTR_REG, _REG_CTR)
CFI_OFFSET_DWARF_REG(DWARF_XER_REG, _REG_XER)
.cfi_return_column DWARF_SIGRETURN_REG
CFI_OFFSET_DWARF_REG(DWARF_SIGRETURN_REG, _REG_PC)
/*
* The unwind entry includes one instruction slot prior to the trampoline
* because the unwinder will look up to (return PC - 1 insn) while unwinding.
* Normally this would be the jump / branch, but since there isn't one in
* this case, we place an explicit nop there instead.
*/
nop
ENTRY_NOPROFILE(__sigtramp_siginfo_2)
mr %r3,%r30 /* restore ucontext pointer */
_DOSYSCALL(setcontext) /* restore machine state */
_DOSYSCALL(exit) /* or exit with errno if failed */
.cfi_endproc
END(__sigtramp_siginfo_2)
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