1/* $NetBSD: __sigtramp2.S,v 1.5 2022/04/07 20:23:44 andvar Exp $ */ 2 3/*- 4 * Copyright (c) 2002 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32#include "SYS.h" 33#include "assym.h" 34 35#if defined(SYSLIBC_SCCS) && !defined(lint) 36 RCSID("$NetBSD: __sigtramp2.S,v 1.5 2022/04/07 20:23:44 andvar Exp $") 37#endif /* SYSLIBC_SCCS and not lint */ 38 39 40/* 41 * The MIPS signal trampoline is invoked only to return from 42 * the signal; the kernel calls the signal handler directly. 43 * 44 * On entry, stack looks like: 45 * 46 * ucontext structure sp + sizeof(siginfo_t) 47 * sp-> siginfo structure 48 * 49 * The DWARF register numbers for the general purpose registers are the 50 * same as the architected register numbers. For MIPS, there is a DWARF 51 * pseudo-register for signal handler return addresses, as well as for the 52 * MDLO and MDHI registers. 53 */ 54 55#define DWARF_MDHI_REG 64 56#define DWARF_MDLO_REG 65 57 58#if defined(__LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__) 59#define DWARF_SIGRETURN_REG __LIBGCC_DWARF_ALT_FRAME_RETURN_COLUMN__ 60#else 61#define DWARF_SIGRETURN_REG 66 62#endif 63 64#define CFI_OFFSET_DWARF_REG(d, r) .cfi_offset d, r * SZREG 65#define CFI_OFFSET(r) CFI_OFFSET_DWARF_REG(r, r) 66 67 .text 68 .cfi_startproc 69 .cfi_signal_frame 70 .cfi_def_cfa _REG_SP, SIGINFO_SIZE + _UC_GREGS 71 CFI_OFFSET(_REG_R0) 72 CFI_OFFSET(_REG_AT) 73 CFI_OFFSET(_REG_V0) 74 CFI_OFFSET(_REG_V1) 75 CFI_OFFSET(_REG_A0) 76 CFI_OFFSET(_REG_A1) 77 CFI_OFFSET(_REG_A2) 78 CFI_OFFSET(_REG_A3) 79 CFI_OFFSET(_REG_T0) 80 CFI_OFFSET(_REG_T1) 81 CFI_OFFSET(_REG_T2) 82 CFI_OFFSET(_REG_T3) 83 CFI_OFFSET(_REG_T4) 84 CFI_OFFSET(_REG_T5) 85 CFI_OFFSET(_REG_T6) 86 CFI_OFFSET(_REG_T7) 87 CFI_OFFSET(_REG_S0) 88 CFI_OFFSET(_REG_S1) 89 CFI_OFFSET(_REG_S2) 90 CFI_OFFSET(_REG_S3) 91 CFI_OFFSET(_REG_S4) 92 CFI_OFFSET(_REG_S5) 93 CFI_OFFSET(_REG_S6) 94 CFI_OFFSET(_REG_S7) 95 CFI_OFFSET(_REG_T8) 96 CFI_OFFSET(_REG_T9) 97 CFI_OFFSET(_REG_K0) 98 CFI_OFFSET(_REG_K1) 99 CFI_OFFSET(_REG_GP) 100 CFI_OFFSET(_REG_SP) 101 CFI_OFFSET(_REG_S8) 102 CFI_OFFSET(_REG_RA) 103 CFI_OFFSET_DWARF_REG(DWARF_MDHI_REG, _REG_MDHI) 104 CFI_OFFSET_DWARF_REG(DWARF_MDLO_REG, _REG_MDLO) 105 .cfi_return_column DWARF_SIGRETURN_REG 106 CFI_OFFSET_DWARF_REG(DWARF_SIGRETURN_REG, _REG_EPC) 107 108/* 109 * The unwind entry includes one instruction slot prior to the trampoline 110 * because the unwinder will look up to (return PC - 1 insn) while unwinding. 111 * Normally this would be the jump / branch, but since there isn't one in 112 * this case, we place an explicit nop there instead. 113 */ 114 nop 115 116LEAF_NOPROFILE(__sigtramp_siginfo_2) 117 PTR_ADDU a0, sp, SIGINFO_SIZE /* address of ucontext */ 118 SYSTRAP(setcontext) /* and do setcontext */ 119 move a0, v0 /* exit with errno */ 120 SYSTRAP(exit) /* if sigreturn fails */ 121 .cfi_endproc 122END(__sigtramp_siginfo_2) 123