1 /* Copyright (C) 1999-2023 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
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 _LINUX_IA64_SYSDEP_H
19 #define _LINUX_IA64_SYSDEP_H 1
20
21 #include <sysdeps/unix/sysdep.h>
22 #include <sysdeps/unix/sysv/linux/sysdep.h>
23 #include <sysdeps/ia64/sysdep.h>
24 #include <dl-sysdep.h>
25 #include <tls.h>
26 #include <asm/break.h>
27
28 /* In order to get __set_errno() definition in INLINE_SYSCALL. */
29 #ifndef __ASSEMBLER__
30 #include <errno.h>
31 #endif
32
33 /* As of GAS v2.4.90.0.7, including a ".align" directive inside a
34 function will cause bad unwind info to be emitted (GAS doesn't know
35 how to account for the padding introduced by the .align directive).
36 Turning on this macro will work around this bug by introducing the
37 necessary padding explicitly. */
38 #define GAS_ALIGN_BREAKS_UNWIND_INFO
39
40 /* For Linux we can use the system call table in the header file
41 /usr/include/asm/unistd.h
42 of the kernel. But these symbols do not follow the SYS_* syntax
43 so we have to redefine the `SYS_ify' macro here. */
44 #undef SYS_ify
45 #define SYS_ify(syscall_name) __NR_##syscall_name
46
47 #ifndef IA64_USE_NEW_STUB
48 # if defined USE_DL_SYSINFO && IS_IN (libc)
49 # define IA64_USE_NEW_STUB 1
50 # else
51 # define IA64_USE_NEW_STUB 0
52 # endif
53 #endif
54 #if IA64_USE_NEW_STUB && !USE_DL_SYSINFO
55 # error IA64_USE_NEW_STUB needs USE_DL_SYSINFO
56 #endif
57
58 #ifdef __ASSEMBLER__
59
60 #undef CALL_MCOUNT
61 #ifdef PROF
62 # define CALL_MCOUNT \
63 .data; \
64 1: data8 0; /* XXX fixme: use .xdata8 once labels work */ \
65 .previous; \
66 .prologue; \
67 .save ar.pfs, r40; \
68 alloc out0 = ar.pfs, 8, 0, 4, 0; \
69 mov out1 = gp; \
70 .save rp, out2; \
71 mov out2 = rp; \
72 .body; \
73 ;; \
74 addl out3 = @ltoff(1b), gp; \
75 br.call.sptk.many rp = _mcount \
76 ;;
77 #else
78 # define CALL_MCOUNT /* Do nothing. */
79 #endif
80
81 /* Linux uses a negative return value to indicate syscall errors, unlike
82 most Unices, which use the condition codes' carry flag.
83
84 Since version 2.1 the return value of a system call might be negative
85 even if the call succeeded. E.g., the `lseek' system call might return
86 a large offset. Therefore we must not anymore test for < 0, but test
87 for a real error by making sure the value in %d0 is a real error
88 number. Linus said he will make sure the no syscall returns a value
89 in -1 .. -4095 as a valid result so we can safely test with -4095. */
90
91 /* We don't want the label for the error handler to be visible in the symbol
92 table when we define it here. */
93 #undef SYSCALL_ERROR_LABEL
94 #define SYSCALL_ERROR_LABEL __syscall_error
95
96 #undef PSEUDO
97 #define PSEUDO(name, syscall_name, args) \
98 ENTRY(name) \
99 DO_CALL (SYS_ify(syscall_name)); \
100 cmp.eq p6,p0=-1,r10; \
101 (p6) br.cond.spnt.few __syscall_error;
102
103 #define DO_CALL_VIA_BREAK(num) \
104 mov r15=num; \
105 break __IA64_BREAK_SYSCALL
106
107 #if IA64_USE_NEW_STUB
108 # ifdef SHARED
109 # define DO_CALL(num) \
110 .prologue; \
111 adds r2 = SYSINFO_OFFSET, r13;; \
112 ld8 r2 = [r2]; \
113 .save ar.pfs, r11; \
114 mov r11 = ar.pfs;; \
115 .body; \
116 mov r15 = num; \
117 mov b7 = r2; \
118 br.call.sptk.many b6 = b7;; \
119 .restore sp; \
120 mov ar.pfs = r11; \
121 .prologue; \
122 .body
123 # else /* !SHARED */
124 # define DO_CALL(num) \
125 .prologue; \
126 mov r15 = num; \
127 movl r2 = _dl_sysinfo;; \
128 ld8 r2 = [r2]; \
129 .save ar.pfs, r11; \
130 mov r11 = ar.pfs;; \
131 .body; \
132 mov b7 = r2; \
133 br.call.sptk.many b6 = b7;; \
134 .restore sp; \
135 mov ar.pfs = r11; \
136 .prologue; \
137 .body
138 # endif
139 #else
140 # define DO_CALL(num) DO_CALL_VIA_BREAK(num)
141 #endif
142
143 #undef PSEUDO_END
144 #define PSEUDO_END(name) .endp C_SYMBOL_NAME(name);
145
146 #undef PSEUDO_NOERRNO
147 #define PSEUDO_NOERRNO(name, syscall_name, args) \
148 ENTRY(name) \
149 DO_CALL (SYS_ify(syscall_name));
150
151 #undef PSEUDO_END_NOERRNO
152 #define PSEUDO_END_NOERRNO(name) .endp C_SYMBOL_NAME(name);
153
154 #undef PSEUDO_ERRVAL
155 #define PSEUDO_ERRVAL(name, syscall_name, args) \
156 ENTRY(name) \
157 DO_CALL (SYS_ify(syscall_name)); \
158 cmp.eq p6,p0=-1,r10; \
159 (p6) mov r10=r8;
160
161
162 #undef PSEUDO_END_ERRVAL
163 #define PSEUDO_END_ERRVAL(name) .endp C_SYMBOL_NAME(name);
164
165 #undef END
166 #define END(name) \
167 .size C_SYMBOL_NAME(name), . - C_SYMBOL_NAME(name) ; \
168 .endp C_SYMBOL_NAME(name)
169
170 #define ret br.ret.sptk.few b0
171 #define ret_NOERRNO ret
172 #define ret_ERRVAL ret
173
174 #else /* not __ASSEMBLER__ */
175
176 #undef HAVE_INTERNAL_BRK_ADDR_SYMBOL
177 #define HAVE_INTERNAL_BRK_ADDR_SYMBOL 1
178
179 #define BREAK_INSN_1(num) "break " #num ";;\n\t"
180 #define BREAK_INSN(num) BREAK_INSN_1(num)
181
182 /* On IA-64 we have stacked registers for passing arguments. The
183 "out" registers end up being the called function's "in"
184 registers.
185
186 Also, since we have plenty of registers we have two return values
187 from a syscall. r10 is set to -1 on error, whilst r8 contains the
188 (non-negative) errno on error or the return value on success.
189 */
190
191 #if IA64_USE_NEW_STUB
192
193 # define INTERNAL_SYSCALL_NCS(name, nr, args...) \
194 ({ \
195 LOAD_ARGS_##nr (args) \
196 register long _r8 __asm ("r8"); \
197 register long _r10 __asm ("r10"); \
198 register long _r15 __asm ("r15") = name; \
199 register void *_b7 __asm ("b7") = ((tcbhead_t *)__thread_self)->__private;\
200 LOAD_REGS_##nr \
201 /* \
202 * Don't specify any unwind info here. We mark ar.pfs as \
203 * clobbered. This will force the compiler to save ar.pfs \
204 * somewhere and emit appropriate unwind info for that save. \
205 */ \
206 __asm __volatile ("br.call.sptk.many b6=%0;;\n" \
207 : "=b"(_b7), "=r" (_r8), "=r" (_r10), "=r" (_r15) \
208 ASM_OUTARGS_##nr \
209 : "0" (_b7), "3" (_r15) ASM_ARGS_##nr \
210 : "memory", "ar.pfs" ASM_CLOBBERS_##nr); \
211 _r10 == -1 ? -_r8 : _r8; \
212 })
213
214 #else /* !IA64_USE_NEW_STUB */
215
216 # define INTERNAL_SYSCALL_NCS(name, nr, args...) \
217 ({ \
218 LOAD_ARGS_##nr (args) \
219 register long _r8 asm ("r8"); \
220 register long _r10 asm ("r10"); \
221 register long _r15 asm ("r15") = name; \
222 LOAD_REGS_##nr \
223 __asm __volatile (BREAK_INSN (__IA64_BREAK_SYSCALL) \
224 : "=r" (_r8), "=r" (_r10), "=r" (_r15) \
225 ASM_OUTARGS_##nr \
226 : "2" (_r15) ASM_ARGS_##nr \
227 : "memory" ASM_CLOBBERS_##nr); \
228 _r10 == -1 ? -_r8 : _r8; \
229 })
230
231 #endif /* !IA64_USE_NEW_STUB */
232
233 #define INTERNAL_SYSCALL(name, nr, args...) \
234 INTERNAL_SYSCALL_NCS (__NR_##name, nr, ##args)
235
236 #define LOAD_ARGS_0()
237 #define LOAD_REGS_0
238 #define LOAD_ARGS_1(a1) \
239 long _arg1 = (long) (a1); \
240 LOAD_ARGS_0 ()
241 #define LOAD_REGS_1 \
242 register long _out0 asm ("out0") = _arg1; \
243 LOAD_REGS_0
244 #define LOAD_ARGS_2(a1, a2) \
245 long _arg2 = (long) (a2); \
246 LOAD_ARGS_1 (a1)
247 #define LOAD_REGS_2 \
248 register long _out1 asm ("out1") = _arg2; \
249 LOAD_REGS_1
250 #define LOAD_ARGS_3(a1, a2, a3) \
251 long _arg3 = (long) (a3); \
252 LOAD_ARGS_2 (a1, a2)
253 #define LOAD_REGS_3 \
254 register long _out2 asm ("out2") = _arg3; \
255 LOAD_REGS_2
256 #define LOAD_ARGS_4(a1, a2, a3, a4) \
257 long _arg4 = (long) (a4); \
258 LOAD_ARGS_3 (a1, a2, a3)
259 #define LOAD_REGS_4 \
260 register long _out3 asm ("out3") = _arg4; \
261 LOAD_REGS_3
262 #define LOAD_ARGS_5(a1, a2, a3, a4, a5) \
263 long _arg5 = (long) (a5); \
264 LOAD_ARGS_4 (a1, a2, a3, a4)
265 #define LOAD_REGS_5 \
266 register long _out4 asm ("out4") = _arg5; \
267 LOAD_REGS_4
268 #define LOAD_ARGS_6(a1, a2, a3, a4, a5, a6) \
269 long _arg6 = (long) (a6); \
270 LOAD_ARGS_5 (a1, a2, a3, a4, a5)
271 #define LOAD_REGS_6 \
272 register long _out5 asm ("out5") = _arg6; \
273 LOAD_REGS_5
274
275 #define ASM_OUTARGS_0
276 #define ASM_OUTARGS_1 ASM_OUTARGS_0, "=r" (_out0)
277 #define ASM_OUTARGS_2 ASM_OUTARGS_1, "=r" (_out1)
278 #define ASM_OUTARGS_3 ASM_OUTARGS_2, "=r" (_out2)
279 #define ASM_OUTARGS_4 ASM_OUTARGS_3, "=r" (_out3)
280 #define ASM_OUTARGS_5 ASM_OUTARGS_4, "=r" (_out4)
281 #define ASM_OUTARGS_6 ASM_OUTARGS_5, "=r" (_out5)
282
283 #if IA64_USE_NEW_STUB
284 #define ASM_ARGS_0
285 #define ASM_ARGS_1 ASM_ARGS_0, "4" (_out0)
286 #define ASM_ARGS_2 ASM_ARGS_1, "5" (_out1)
287 #define ASM_ARGS_3 ASM_ARGS_2, "6" (_out2)
288 #define ASM_ARGS_4 ASM_ARGS_3, "7" (_out3)
289 #define ASM_ARGS_5 ASM_ARGS_4, "8" (_out4)
290 #define ASM_ARGS_6 ASM_ARGS_5, "9" (_out5)
291 #else
292 #define ASM_ARGS_0
293 #define ASM_ARGS_1 ASM_ARGS_0, "3" (_out0)
294 #define ASM_ARGS_2 ASM_ARGS_1, "4" (_out1)
295 #define ASM_ARGS_3 ASM_ARGS_2, "5" (_out2)
296 #define ASM_ARGS_4 ASM_ARGS_3, "6" (_out3)
297 #define ASM_ARGS_5 ASM_ARGS_4, "7" (_out4)
298 #define ASM_ARGS_6 ASM_ARGS_5, "8" (_out5)
299 #endif
300
301 #define ASM_CLOBBERS_0 ASM_CLOBBERS_1, "out0"
302 #define ASM_CLOBBERS_1 ASM_CLOBBERS_2, "out1"
303 #define ASM_CLOBBERS_2 ASM_CLOBBERS_3, "out2"
304 #define ASM_CLOBBERS_3 ASM_CLOBBERS_4, "out3"
305 #define ASM_CLOBBERS_4 ASM_CLOBBERS_5, "out4"
306 #define ASM_CLOBBERS_5 ASM_CLOBBERS_6, "out5"
307 #define ASM_CLOBBERS_6_COMMON , "out6", "out7", \
308 /* Non-stacked integer registers, minus r8, r10, r15. */ \
309 "r2", "r3", "r9", "r11", "r13", "r14", "r16", "r17", "r18", \
310 "r19", "r20", "r21", "r22", "r23", "r24", "r25", "r26", "r27", \
311 "r28", "r29", "r30", "r31", \
312 /* Predicate registers. */ \
313 "p6", "p7", "p8", "p9", "p10", "p11", "p12", "p13", "p14", "p15", \
314 /* Non-rotating fp registers. */ \
315 "f6", "f7", "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15", \
316 /* Branch registers. */ \
317 "b6"
318
319 #if IA64_USE_NEW_STUB
320 # define ASM_CLOBBERS_6 ASM_CLOBBERS_6_COMMON
321 #else
322 # define ASM_CLOBBERS_6 ASM_CLOBBERS_6_COMMON , "b7"
323 #endif
324
325 #endif /* not __ASSEMBLER__ */
326
327 #endif /* linux/ia64/sysdep.h */