1 /* Restartable Sequences Linux mips architecture header. 2 Copyright (C) 2021-2022 Free Software Foundation, Inc. 3 4 The GNU C Library is free software; you can redistribute it and/or 5 modify it under the terms of the GNU Lesser General Public 6 License as published by the Free Software Foundation; either 7 version 2.1 of the License, or (at your option) any later version. 8 9 The GNU C Library is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 Lesser General Public License for more details. 13 14 You should have received a copy of the GNU Lesser General Public 15 License along with the GNU C Library; if not, see 16 <https://www.gnu.org/licenses/>. */ 17 18 #ifndef _SYS_RSEQ_H 19 # error "Never use <bits/rseq.h> directly; include <sys/rseq.h> instead." 20 #endif 21 22 /* RSEQ_SIG is a signature required before each abort handler code. 23 24 It is a 32-bit value that maps to actual architecture code compiled 25 into applications and libraries. It needs to be defined for each 26 architecture. When choosing this value, it needs to be taken into 27 account that generating invalid instructions may have ill effects on 28 tools like objdump, and may also have impact on the CPU speculative 29 execution efficiency in some cases. 30 31 RSEQ_SIG uses the break instruction. The instruction pattern is: 32 33 On MIPS: 34 0350000d break 0x350 35 36 On nanoMIPS: 37 00100350 break 0x350 38 39 On microMIPS: 40 0000d407 break 0x350 41 42 For nanoMIPS32 and microMIPS, the instruction stream is encoded as 43 16-bit halfwords, so the signature halfwords need to be swapped 44 accordingly for little-endian. */ 45 46 #if defined (__nanomips__) 47 # ifdef __MIPSEL__ 48 # define RSEQ_SIG 0x03500010 49 # else 50 # define RSEQ_SIG 0x00100350 51 # endif 52 #elif defined (__mips_micromips) 53 # ifdef __MIPSEL__ 54 # define RSEQ_SIG 0xd4070000 55 # else 56 # define RSEQ_SIG 0x0000d407 57 # endif 58 #elif defined (__mips__) 59 # define RSEQ_SIG 0x0350000d 60 #else 61 /* Unknown MIPS architecture. */ 62 #endif 63