summaryrefslogtreecommitdiff
path: root/libc/sysdeps/linux/sh/sysdep.h
blob: 281c4158e91a41cc84d290136faf50dc88bb11a2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
/* Assembler macros for SH.
   Copyright (C) 1999, 2000, 2005 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

#include <common/sysdep.h>

#include <features.h>

#ifdef	__ASSEMBLER__

/* Syntactic details of assembler.  */

#define LOCAL(X)	.L_##X
#define ALIGNARG(log2) log2
/* For ELF we need the `.type' directive to make shared libs work right.  */
#define ASM_TYPE_DIRECTIVE(name,typearg) .type name,@##typearg;
#define ASM_SIZE_DIRECTIVE(name) .size name,.-name

#ifdef SHARED
#define PLTJMP(_x)	_x##@PLT
#else
#define PLTJMP(_x)	_x
#endif

/* Define an entry point visible from C.  */
#define	ENTRY(name)							      \
  .globl C_SYMBOL_NAME(name);				      \
  ASM_TYPE_DIRECTIVE (C_SYMBOL_NAME(name),function)			      \
  .align ALIGNARG(5);							      \
  C_LABEL(name)								      \
  cfi_startproc;							      \
  CALL_MCOUNT

#undef	END
#define END(name)							      \
  cfi_endproc;								      \
  ASM_SIZE_DIRECTIVE(C_SYMBOL_NAME(name))

/* If compiled for profiling, call `mcount' at the start of each function.  */
#ifdef	PROF
#define CALL_MCOUNT					\
	mov.l	1f,r1;					\
	sts.l	pr,@-r15;				\
	cfi_adjust_cfa_offset (4);			\
	cfi_rel_offset (pr, 0);				\
	mova	2f,r0;					\
	jmp	@r1;					\
	 lds	r0,pr;					\
	.align	2;					\
1:	.long	mcount;					\
2:	lds.l	@r15+,pr;				\
	cfi_adjust_cfa_offset (-4);			\
	cfi_restore (pr)

#else
#define CALL_MCOUNT		/* Do nothing.  */
#endif

#ifdef	__UCLIBC_UNDERSCORES__
/* Since C identifiers are not normally prefixed with an underscore
   on this system, the asm identifier `syscall_error' intrudes on the
   C name space.  Make sure we use an innocuous name.  */
#define	syscall_error	__syscall_error
#define mcount		_mcount
#endif

/* For Linux we can use the system call table in the header file
	/usr/include/asm/unistd.h
   of the kernel.  But these symbols do not follow the SYS_* syntax
   so we have to redefine the `SYS_ify' macro here.  */
#undef SYS_ify
#define SYS_ify(syscall_name)	(__NR_##syscall_name)

#define ret	rts ; nop
/* The sh move insn is s, d.  */
#define MOVE(x,y)	mov x , y

/* Linux uses a negative return value to indicate syscall errors,
   unlike most Unices, which use the condition codes' carry flag.

   Since version 2.1 the return value of a system call might be
   negative even if the call succeeded.  E.g., the `lseek' system call
   might return a large offset.  Therefore we must not anymore test
   for < 0, but test for a real error by making sure the value in R0
   is a real error number.  Linus said he will make sure the no syscall
   returns a value in -1 .. -4095 as a valid result so we can savely
   test with -4095.  */

#define _IMM1 #-1
#define _IMM12 #-12
#undef	PSEUDO
#define	PSEUDO(name, syscall_name, args) \
 .text; \
 ENTRY (name); \
    DO_CALL (syscall_name, args); \
    mov r0,r1; \
    mov _IMM12,r2; \
    shad r2,r1; \
    not r1,r1; \
    tst r1,r1; \
    bf .Lpseudo_end; \
    SYSCALL_ERROR_HANDLER; \
 .Lpseudo_end:

#undef	PSEUDO_END
#define	PSEUDO_END(name) \
  END (name)

#undef	PSEUDO_NOERRNO
#define	PSEUDO_NOERRNO(name, syscall_name, args) \
 .text; \
 ENTRY (name); \
    DO_CALL (syscall_name, args)

#undef	PSEUDO_END_NOERRNO
#define	PSEUDO_END_NOERRNO(name) \
  END (name)

#define ret_NOERRNO ret

#define	PSEUDO_ERRVAL(name, syscall_name, args) \
 .text; \
 ENTRY (name); \
    DO_CALL (syscall_name, args);

#undef	PSEUDO_END_ERRVAL
#define	PSEUDO_END_ERRVAL(name) \
  END (name)

#ifndef __PIC__
# define SYSCALL_ERROR_HANDLER	\
	mov.l 0f,r1; \
	jmp @r1; \
	 mov r0,r4; \
	.align 2; \
     0: .long __syscall_error

#include <libc/sysdeps/linux/sh/syscall_error.S>
#else
# ifdef RTLD_PRIVATE_ERRNO

#  define SYSCALL_ERROR_HANDLER	\
	neg r0,r1; \
	mov.l 0f,r12; \
	mova 0f,r0; \
	add r0,r12; \
	mov.l 1f,r0; \
	mov.l r1,@(r0,r12)
	bra .Lpseudo_end; \
	 mov _IMM1,r0; \
	.align 2; \
     0: .long _GLOBAL_OFFSET_TABLE_; \
     1: .long rtld_errno@GOTOFF

# elif defined _LIBC_REENTRANT

#  if defined USE___THREAD

#   ifndef NOT_IN_libc
#    define SYSCALL_ERROR_ERRNO __libc_errno
#   else
#    define SYSCALL_ERROR_ERRNO errno
#   endif
#   define SYSCALL_ERROR_HANDLER \
	neg r0,r1; \
	mov r12,r2; \
	mov.l 0f,r12; \
	mova 0f,r0; \
	add r0,r12; \
	mov.l 1f,r0; \
	stc gbr, r4; \
	mov.l @(r0,r12),r0; \
	bra .Lskip; \
	add r4,r0; \
	.align 2; \
	1: .long SYSCALL_ERROR_ERRNO@GOTTPOFF; \
	.Lskip: \
	mov r2,r12; \
	mov.l r1,@r0; \
	bra .Lpseudo_end; \
	mov _IMM1,r0; \
	.align 2; \
	0: .long _GLOBAL_OFFSET_TABLE_
#  else

#   define SYSCALL_ERROR_HANDLER \
	neg r0,r1; \
	mov.l r14,@-r15; \
	mov.l r12,@-r15; \
	mov.l r1,@-r15; \
	mov.l 0f,r12; \
	mova 0f,r0; \
	add r0,r12; \
	sts.l pr,@-r15; \
	mov r15,r14; \
	mov.l 1f,r1; \
	bsrf r1; \
         nop; \
     2: mov r14,r15; \
	lds.l @r15+,pr; \
	mov.l @r15+,r1; \
	mov.l r1,@r0; \
	mov.l @r15+,r12; \
	mov.l @r15+,r14; \
	bra .Lpseudo_end; \
	 mov _IMM1,r0; \
	.align 2; \
     0: .long _GLOBAL_OFFSET_TABLE_; \
     1: .long PLTJMP(C_SYMBOL_NAME(__errno_location))-(2b-.)
/* A quick note: it is assumed that the call to `__errno_location' does
   not modify the stack!  */
#  endif
# else

/* Store (-r0) into errno through the GOT.  */
#  define SYSCALL_ERROR_HANDLER						      \
	neg r0,r1; \
	mov r12,r2; \
	mov.l 0f,r12; \
	mova 0f,r0; \
	add r0,r12; \
	mov.l 1f,r0; \
	mov.l @(r0,r12),r0; \
	mov r2,r12; \
	mov.l r1,@r0; \
	bra .Lpseudo_end; \
	 mov _IMM1,r0; \
	.align 2; \
     0: .long _GLOBAL_OFFSET_TABLE_; \
     1: .long errno@GOT
# endif	/* _LIBC_REENTRANT */
#endif	/* __PIC__ */

# ifdef __SH4__
#  define SYSCALL_INST_PAD \
	or r0,r0; or r0,r0; or r0,r0; or r0,r0; or r0,r0
# else
#  define SYSCALL_INST_PAD
# endif

#define SYSCALL_INST0	trapa #0x10
#define SYSCALL_INST1	trapa #0x11
#define SYSCALL_INST2	trapa #0x12
#define SYSCALL_INST3	trapa #0x13
#define SYSCALL_INST4	trapa #0x14
#define SYSCALL_INST5	mov.l @(0,r15),r0; trapa #0x15
#define SYSCALL_INST6	mov.l @(0,r15),r0; mov.l @(4,r15),r1; trapa #0x16

#undef	DO_CALL
#define DO_CALL(syscall_name, args)	\
    mov.l 1f,r3;			\
    SYSCALL_INST##args;			\
    SYSCALL_INST_PAD;			\
    bra 2f;				\
     nop;				\
    .align 2;				\
 1: .long SYS_ify (syscall_name);	\
 2:
#endif	/* __ASSEMBLER__ */