1 /* Definitions for Intel 386 running Linux-based GNU systems with ELF format.
2 Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2001, 2002
3 Free Software Foundation, Inc.
4 Contributed by Eric Youngdale.
5 Modified for stabs-in-ELF by H.J. Lu.
7 This file is part of GNU CC.
9 GNU CC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GNU CC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GNU CC; see the file COPYING. If not, write to
21 the Free Software Foundation, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 #define LINUX_DEFAULT_ELF
26 /* Output at beginning of assembler file. */
27 /* The .file command should always begin the output. */
28 #define TARGET_ASM_FILE_START_FILE_DIRECTIVE true
30 #define TARGET_VERSION fprintf (stderr, " (i386 Linux/ELF)");
32 /* The svr4 ABI for the i386 says that records and unions are returned
34 #undef DEFAULT_PCC_STRUCT_RETURN
35 #define DEFAULT_PCC_STRUCT_RETURN 1
37 /* We arrange for the whole %gs segment to map the tls area. */
38 #undef TARGET_TLS_DIRECT_SEG_REFS_DEFAULT
39 #define TARGET_TLS_DIRECT_SEG_REFS_DEFAULT MASK_TLS_DIRECT_SEG_REFS
41 #undef ASM_COMMENT_START
42 #define ASM_COMMENT_START "#"
44 #undef DBX_REGISTER_NUMBER
45 #define DBX_REGISTER_NUMBER(n) \
46 (TARGET_64BIT ? dbx64_register_map[n] : svr4_dbx_register_map[n])
48 /* Output assembler code to FILE to call the profiler.
49 To the best of my knowledge, no Linux libc has required the label
50 argument to mcount. */
52 #define NO_PROFILE_COUNTERS 1
55 #define MCOUNT_NAME "mcount"
57 /* The GLIBC version of mcount for the x86 assumes that there is a
58 frame, so we cannot allow profiling without a frame pointer. */
60 #undef SUBTARGET_FRAME_POINTER_REQUIRED
61 #define SUBTARGET_FRAME_POINTER_REQUIRED current_function_profile
64 #define SIZE_TYPE "unsigned int"
67 #define PTRDIFF_TYPE "int"
70 #define WCHAR_TYPE "long int"
72 #undef WCHAR_TYPE_SIZE
73 #define WCHAR_TYPE_SIZE BITS_PER_WORD
75 #define TARGET_OS_CPP_BUILTINS() \
78 builtin_define_std ("linux"); \
79 builtin_define_std ("unix"); \
80 builtin_define ("__gnu_linux__"); \
81 builtin_assert ("system=posix"); \
84 builtin_define ("__PIC__"); \
85 builtin_define ("__pic__"); \
92 #define CPP_SPEC "%{posix:-D_POSIX_SOURCE}"
94 #define CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_REENTRANT}"
98 #define CC1_SPEC "%(cc1_cpu) %{profile:-p}"
100 /* Provide a LINK_SPEC appropriate for Linux. Here we provide support
101 for the special GCC options -static and -shared, which allow us to
102 link things in one of these three modes by applying the appropriate
103 combinations of options at link-time. We like to support here for
104 as many of the other GNU linker options as possible. But I don't
105 have the time to search for those flags. I am sure how to add
106 support for -soname shared_object_name. H.J.
108 I took out %{v:%{!V:-V}}. It is too much :-(. They can use
111 When the -shared link option is used a final link is not being
114 /* If ELF is the default format, we should not use /lib/elf. */
118 #ifndef LINUX_DEFAULT_ELF
119 #define LINK_SPEC "-m elf_i386 %{shared:-shared} \
123 %{rdynamic:-export-dynamic} \
124 %{!dynamic-linker:-dynamic-linker /lib/elf/ld-linux.so.1} \
125 %{!rpath:-rpath /lib/elf/}} %{static:-static}}}"
127 #define LINK_SPEC "-m elf_i386 %{shared:-shared} \
131 %{rdynamic:-export-dynamic} \
132 %{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.1}} \
136 #define LINK_SPEC "-m elf_i386 %{shared:-shared} \
140 %{rdynamic:-export-dynamic} \
141 %{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.2}} \
145 /* A C statement (sans semicolon) to output to the stdio stream
146 FILE the assembler definition of uninitialized global DECL named
147 NAME whose size is SIZE bytes and alignment is ALIGN bytes.
148 Try to use asm_output_aligned_bss to implement this macro. */
150 #define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \
151 asm_output_aligned_bss (FILE, DECL, NAME, SIZE, ALIGN)
153 /* A C statement to output to the stdio stream FILE an assembler
154 command to advance the location counter to a multiple of 1<<LOG
155 bytes if it is within MAX_SKIP bytes.
157 This is used to align code labels according to Intel recommendations. */
159 #ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
160 #define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \
163 if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
164 else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
169 #if defined(__PIC__) && defined (USE_GNULIBC_1)
170 /* This is a kludge. The i386 GNU/Linux dynamic linker needs ___brk_addr,
171 __environ and atexit. We have to make sure they are in the .dynsym
172 section. We do this by forcing the assembler to create undefined
173 references to these symbols in the object file. */
174 #undef CRT_CALL_STATIC_FUNCTION
175 #define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC) \
176 asm (SECTION_OP "\n\t" \
177 "call " USER_LABEL_PREFIX #FUNC "\n" \
178 TEXT_SECTION_ASM_OP "\n\t" \
179 ".extern ___brk_addr\n\t" \
180 ".type ___brk_addr,@object\n\t" \
181 ".extern __environ\n\t" \
182 ".type __environ,@object\n\t" \
183 ".extern atexit\n\t" \
184 ".type atexit,@function");
187 /* Handle special EH pointer encodings. Absolute, pc-relative, and
188 indirect are handled automatically. */
189 #define ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX(FILE, ENCODING, SIZE, ADDR, DONE) \
191 if ((SIZE) == 4 && ((ENCODING) & 0x70) == DW_EH_PE_datarel) \
193 fputs (ASM_LONG, FILE); \
194 assemble_name (FILE, XSTR (ADDR, 0)); \
195 fputs (((ENCODING) & DW_EH_PE_indirect ? "@GOT" : "@GOTOFF"), FILE); \
200 /* Used by crtstuff.c to initialize the base of data-relative relocations.
201 These are GOT relative on x86, so return the pic register. */
203 #define CRT_GET_RFIB_DATA(BASE) \
205 register void *ebx_ __asm__("ebx"); \
209 #define CRT_GET_RFIB_DATA(BASE) \
210 __asm__ ("call\t.LPR%=\n" \
213 /* Due to a GAS bug, this cannot use EAX. That encodes \
214 smaller than the traditional EBX, which results in the \
215 offset being off by one. */ \
216 "addl\t$_GLOBAL_OFFSET_TABLE_+[.-.LPR%=],%0" \
220 #undef NEED_INDICATE_EXEC_STACK
221 #define NEED_INDICATE_EXEC_STACK 1
223 /* Do code reading to identify a signal frame, and set the frame
224 state data appropriately. See unwind-dw2.c for the structs. */
227 /* There's no sys/ucontext.h for some (all?) libc1, so no
228 signal-turned-exceptions for them. There's also no configure-run for
229 the target, so we can't check on (e.g.) HAVE_SYS_UCONTEXT_H. Using the
230 target libc1 macro should be enough. */
231 #if !(defined (USE_GNULIBC_1) || (__GLIBC__ == 2 && __GLIBC_MINOR__ == 0))
233 #include <sys/ucontext.h>
235 #define MD_FALLBACK_FRAME_STATE_FOR(CONTEXT, FS, SUCCESS) \
237 unsigned char *pc_ = (CONTEXT)->ra; \
238 struct sigcontext *sc_; \
241 /* popl %eax ; movl $__NR_sigreturn,%eax ; int $0x80 */ \
242 if (*(unsigned short *)(pc_+0) == 0xb858 \
243 && *(unsigned int *)(pc_+2) == 119 \
244 && *(unsigned short *)(pc_+6) == 0x80cd) \
245 sc_ = (CONTEXT)->cfa + 4; \
246 /* movl $__NR_rt_sigreturn,%eax ; int $0x80 */ \
247 else if (*(unsigned char *)(pc_+0) == 0xb8 \
248 && *(unsigned int *)(pc_+1) == 173 \
249 && *(unsigned short *)(pc_+5) == 0x80cd) \
251 struct rt_sigframe { \
253 struct siginfo *pinfo; \
255 struct siginfo info; \
256 struct ucontext uc; \
257 } *rt_ = (CONTEXT)->cfa; \
258 sc_ = (struct sigcontext *) &rt_->uc.uc_mcontext; \
263 new_cfa_ = sc_->esp; \
264 (FS)->cfa_how = CFA_REG_OFFSET; \
266 (FS)->cfa_offset = new_cfa_ - (long) (CONTEXT)->cfa; \
268 /* The SVR4 register numbering macros aren't usable in libgcc. */ \
269 (FS)->regs.reg[0].how = REG_SAVED_OFFSET; \
270 (FS)->regs.reg[0].loc.offset = (long)&sc_->eax - new_cfa_; \
271 (FS)->regs.reg[3].how = REG_SAVED_OFFSET; \
272 (FS)->regs.reg[3].loc.offset = (long)&sc_->ebx - new_cfa_; \
273 (FS)->regs.reg[1].how = REG_SAVED_OFFSET; \
274 (FS)->regs.reg[1].loc.offset = (long)&sc_->ecx - new_cfa_; \
275 (FS)->regs.reg[2].how = REG_SAVED_OFFSET; \
276 (FS)->regs.reg[2].loc.offset = (long)&sc_->edx - new_cfa_; \
277 (FS)->regs.reg[6].how = REG_SAVED_OFFSET; \
278 (FS)->regs.reg[6].loc.offset = (long)&sc_->esi - new_cfa_; \
279 (FS)->regs.reg[7].how = REG_SAVED_OFFSET; \
280 (FS)->regs.reg[7].loc.offset = (long)&sc_->edi - new_cfa_; \
281 (FS)->regs.reg[5].how = REG_SAVED_OFFSET; \
282 (FS)->regs.reg[5].loc.offset = (long)&sc_->ebp - new_cfa_; \
283 (FS)->regs.reg[8].how = REG_SAVED_OFFSET; \
284 (FS)->regs.reg[8].loc.offset = (long)&sc_->eip - new_cfa_; \
285 (FS)->retaddr_column = 8; \
288 #endif /* not USE_GNULIBC_1 */
289 #endif /* IN_LIBGCC2 */