1/* Assembler macros for ARC.
2 Copyright (C) 2020-2026 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#ifndef _LINUX_ARC_SYSDEP_H
20#define _LINUX_ARC_SYSDEP_H 1
21
22#include <sysdeps/arc/sysdep.h>
23#include <bits/wordsize.h>
24#include <sysdeps/unix/sysdep.h>
25#include <sysdeps/unix/sysv/linux/sysdep.h>
26
27/* "workarounds" for generic code needing to handle 64-bit time_t. */
28
29/* Fix sysdeps/unix/sysv/linux/clock_getcpuclockid.c. */
30#define __NR_clock_getres __NR_clock_getres_time64
31/* Fix sysdeps/nptl/lowlevellock-futex.h. */
32#define __NR_futex __NR_futex_time64
33/* Fix sysdeps/unix/sysv/linux/pause.c. */
34#define __NR_ppoll __NR_ppoll_time64
35/* Fix sysdeps/unix/sysv/linux/select.c. */
36#define __NR_pselect6 __NR_pselect6_time64
37/* Fix sysdeps/unix/sysv/linux/recvmmsg.c. */
38#define __NR_recvmmsg __NR_recvmmsg_time64
39/* Fix sysdeps/unix/sysv/linux/sigtimedwait.c. */
40#define __NR_rt_sigtimedwait __NR_rt_sigtimedwait_time64
41/* Fix sysdeps/unix/sysv/linux/semtimedop.c. */
42#define __NR_semtimedop __NR_semtimedop_time64
43/* Hack sysdeps/unix/sysv/linux/generic/utimes.c. */
44#define __NR_utimensat __NR_utimensat_time64
45
46/* For RTLD_PRIVATE_ERRNO. */
47#include <dl-sysdep.h>
48
49#include <tls.h>
50
51#undef SYS_ify
52#define SYS_ify(syscall_name) __NR_##syscall_name
53
54#ifdef __ASSEMBLER__
55
56/* This is a "normal" system call stub: if there is an error,
57 it returns -1 and sets errno. */
58
59# undef PSEUDO
60# define PSEUDO(name, syscall_name, args) \
61 PSEUDO_NOERRNO(name, syscall_name, args) ASM_LINE_SEP \
62 brhi r0, -4096, L (call_syscall_err) ASM_LINE_SEP
63
64# define ret j_s [blink]
65
66# undef PSEUDO_END
67# define PSEUDO_END(name) \
68 SYSCALL_ERROR_HANDLER ASM_LINE_SEP \
69 END (name)
70
71/* --------- Helper for SYSCALL_NOERRNO -----------
72 This kind of system call stub never returns an error.
73 We return the return value register to the caller unexamined. */
74
75# undef PSEUDO_NOERRNO
76# define PSEUDO_NOERRNO(name, syscall_name, args) \
77 .text ASM_LINE_SEP \
78 ENTRY (name) ASM_LINE_SEP \
79 DO_CALL (syscall_name, args) ASM_LINE_SEP \
80
81/* Return the return value register unexamined. Since r0 is both
82 syscall return reg and function return reg, no work needed. */
83# define ret_NOERRNO \
84 j_s [blink] ASM_LINE_SEP
85
86# undef PSEUDO_END_NOERRNO
87# define PSEUDO_END_NOERRNO(name) \
88 END (name)
89
90/* --------- Helper for SYSCALL_ERRVAL -----------
91 This kind of system call stub returns the errno code as its return
92 value, or zero for success. We may massage the kernel's return value
93 to meet that ABI, but we never set errno here. */
94
95# undef PSEUDO_ERRVAL
96# define PSEUDO_ERRVAL(name, syscall_name, args) \
97 PSEUDO_NOERRNO(name, syscall_name, args) ASM_LINE_SEP
98
99/* Don't set errno, return kernel error (in errno form) or zero. */
100# define ret_ERRVAL \
101 rsub r0, r0, 0 ASM_LINE_SEP \
102 ret_NOERRNO
103
104# undef PSEUDO_END_ERRVAL
105# define PSEUDO_END_ERRVAL(name) \
106 END (name)
107
108
109/* To reduce the code footprint, we confine the actual errno access
110 to single place in __syscall_error().
111 This takes raw kernel error value, sets errno and returns -1. */
112# if IS_IN (libc)
113# define CALL_ERRNO_SETTER_C bl PLTJMP(HIDDEN_JUMPTARGET(__syscall_error))
114# else
115# define CALL_ERRNO_SETTER_C bl PLTJMP(__syscall_error)
116# endif
117
118# define SYSCALL_ERROR_HANDLER \
119L (call_syscall_err): ASM_LINE_SEP \
120 push_s blink ASM_LINE_SEP \
121 cfi_adjust_cfa_offset (4) ASM_LINE_SEP \
122 cfi_rel_offset (blink, 0) ASM_LINE_SEP \
123 CALL_ERRNO_SETTER_C ASM_LINE_SEP \
124 pop_s blink ASM_LINE_SEP \
125 cfi_adjust_cfa_offset (-4) ASM_LINE_SEP \
126 cfi_restore (blink) ASM_LINE_SEP \
127 j_s [blink]
128
129# define DO_CALL(syscall_name, args) \
130 mov r8, __NR_##syscall_name ASM_LINE_SEP \
131 ARC_TRAP_INSN ASM_LINE_SEP
132
133# define ARC_TRAP_INSN trap_s 0
134
135#else /* !__ASSEMBLER__ */
136
137# if IS_IN (libc)
138extern long int __syscall_error (long int);
139hidden_proto (__syscall_error)
140# endif
141
142# define ARC_TRAP_INSN "trap_s 0 \n\t"
143
144# define HAVE_CLONE3_WRAPPER 1
145
146# undef INTERNAL_SYSCALL_NCS
147# define INTERNAL_SYSCALL_NCS(number, nr_args, args...) \
148 ({ \
149 /* Per ABI, r0 is 1st arg and return reg. */ \
150 register long int __ret __asm__("r0"); \
151 register long int _sys_num __asm__("r8"); \
152 \
153 LOAD_ARGS_##nr_args (number, args) \
154 \
155 __asm__ volatile ( \
156 ARC_TRAP_INSN \
157 : "+r" (__ret) \
158 : "r"(_sys_num) ASM_ARGS_##nr_args \
159 : "memory"); \
160 \
161 __ret; })
162
163# undef INTERNAL_SYSCALL
164# define INTERNAL_SYSCALL(name, nr, args...) \
165 INTERNAL_SYSCALL_NCS(__NR_##name, nr, args)
166
167/* Macros for setting up inline __asm__ input regs. */
168# define ASM_ARGS_0
169# define ASM_ARGS_1 ASM_ARGS_0, "r" (__ret)
170# define ASM_ARGS_2 ASM_ARGS_1, "r" (_arg2)
171# define ASM_ARGS_3 ASM_ARGS_2, "r" (_arg3)
172# define ASM_ARGS_4 ASM_ARGS_3, "r" (_arg4)
173# define ASM_ARGS_5 ASM_ARGS_4, "r" (_arg5)
174# define ASM_ARGS_6 ASM_ARGS_5, "r" (_arg6)
175# define ASM_ARGS_7 ASM_ARGS_6, "r" (_arg7)
176
177/* Macros for converting sys-call wrapper args into sys call args. */
178# define LOAD_ARGS_0(nm, arg) \
179 _sys_num = (long int) (nm);
180
181# define LOAD_ARGS_1(nm, arg1) \
182 __ret = (long int) (arg1); \
183 LOAD_ARGS_0 (nm, arg1)
184
185/* Note that the use of _tmpX might look superfluous, however it is needed
186 to ensure that register variables are not clobbered if arg happens to be
187 a function call itself. e.g. sched_setaffinity() calling getpid() for arg2
188 Also this specific order of recursive calling is important to segregate
189 the tmp args evaluation (function call case described above) and assignment
190 of register variables. */
191
192# define LOAD_ARGS_2(nm, arg1, arg2) \
193 long int _tmp2 = (long int) (arg2); \
194 LOAD_ARGS_1 (nm, arg1) \
195 register long int _arg2 __asm__ ("r1") = _tmp2;
196
197# define LOAD_ARGS_3(nm, arg1, arg2, arg3) \
198 long int _tmp3 = (long int) (arg3); \
199 LOAD_ARGS_2 (nm, arg1, arg2) \
200 register long int _arg3 __asm__ ("r2") = _tmp3;
201
202#define LOAD_ARGS_4(nm, arg1, arg2, arg3, arg4) \
203 long int _tmp4 = (long int) (arg4); \
204 LOAD_ARGS_3 (nm, arg1, arg2, arg3) \
205 register long int _arg4 __asm__ ("r3") = _tmp4;
206
207# define LOAD_ARGS_5(nm, arg1, arg2, arg3, arg4, arg5) \
208 long int _tmp5 = (long int) (arg5); \
209 LOAD_ARGS_4 (nm, arg1, arg2, arg3, arg4) \
210 register long int _arg5 __asm__ ("r4") = _tmp5;
211
212# define LOAD_ARGS_6(nm, arg1, arg2, arg3, arg4, arg5, arg6)\
213 long int _tmp6 = (long int) (arg6); \
214 LOAD_ARGS_5 (nm, arg1, arg2, arg3, arg4, arg5) \
215 register long int _arg6 __asm__ ("r5") = _tmp6;
216
217# define LOAD_ARGS_7(nm, arg1, arg2, arg3, arg4, arg5, arg6, arg7)\
218 long int _tmp7 = (int) (arg7); \
219 LOAD_ARGS_6 (nm, arg1, arg2, arg3, arg4, arg5, arg6) \
220 register long int _arg7 __asm__ ("r6") = _tmp7;
221
222# undef HAVE_INTERNAL_BRK_ADDR_SYMBOL
223# define HAVE_INTERNAL_BRK_ADDR_SYMBOL 1
224
225#endif /* !__ASSEMBLER__ */
226
227#endif /* linux/arc/sysdep.h */