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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. */
29 #define ASM_FILE_START(FILE) \
31 output_file_directive (FILE, main_input_filename); \
32 if (ix86_asm_dialect == ASM_INTEL) \
33 fputs ("\t.intel_syntax\n", FILE); \
36 #define TARGET_VERSION fprintf (stderr, " (i386 Linux/ELF)");
38 /* The svr4 ABI for the i386 says that records and unions are returned
40 #undef DEFAULT_PCC_STRUCT_RETURN
41 #define DEFAULT_PCC_STRUCT_RETURN 1
43 #undef ASM_COMMENT_START
44 #define ASM_COMMENT_START "#"
46 #undef DBX_REGISTER_NUMBER
47 #define DBX_REGISTER_NUMBER(n) \
48 (TARGET_64BIT ? dbx64_register_map[n] : svr4_dbx_register_map[n])
50 /* Output assembler code to FILE to call the profiler.
51 To the best of my knowledge, no Linux libc has required the label
52 argument to mcount. */
54 #define NO_PROFILE_COUNTERS
57 #define MCOUNT_NAME "mcount"
59 /* The GLIBC version of mcount for the x86 assumes that there is a
60 frame, so we cannot allow profiling without a frame pointer. */
62 #undef SUBTARGET_FRAME_POINTER_REQUIRED
63 #define SUBTARGET_FRAME_POINTER_REQUIRED current_function_profile
66 #define SIZE_TYPE "unsigned int"
69 #define PTRDIFF_TYPE "int"
72 #define WCHAR_TYPE "long int"
74 #undef WCHAR_TYPE_SIZE
75 #define WCHAR_TYPE_SIZE BITS_PER_WORD
77 #define TARGET_OS_CPP_BUILTINS() \
80 builtin_define_std ("linux"); \
81 builtin_define_std ("unix"); \
82 builtin_define ("__ELF__"); \
83 builtin_define ("__gnu_linux__"); \
84 builtin_assert ("system=posix"); \
87 builtin_define ("__PIC__"); \
88 builtin_define ("__pic__"); \
95 #define CPP_SPEC "%{posix:-D_POSIX_SOURCE}"
97 #define CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_REENTRANT}"
101 #define CC1_SPEC "%(cc1_cpu) %{profile:-p}"
103 /* Provide a LINK_SPEC appropriate for Linux. Here we provide support
104 for the special GCC options -static and -shared, which allow us to
105 link things in one of these three modes by applying the appropriate
106 combinations of options at link-time. We like to support here for
107 as many of the other GNU linker options as possible. But I don't
108 have the time to search for those flags. I am sure how to add
109 support for -soname shared_object_name. H.J.
111 I took out %{v:%{!V:-V}}. It is too much :-(. They can use
114 When the -shared link option is used a final link is not being
117 /* If ELF is the default format, we should not use /lib/elf. */
121 #ifndef LINUX_DEFAULT_ELF
122 #define LINK_SPEC "-m elf_i386 %{shared:-shared} \
126 %{rdynamic:-export-dynamic} \
127 %{!dynamic-linker:-dynamic-linker /lib/elf/ld-linux.so.1} \
128 %{!rpath:-rpath /lib/elf/}} %{static:-static}}}"
130 #define LINK_SPEC "-m elf_i386 %{shared:-shared} \
134 %{rdynamic:-export-dynamic} \
135 %{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.1}} \
139 #define LINK_SPEC "-m elf_i386 %{shared:-shared} \
143 %{rdynamic:-export-dynamic} \
144 %{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.2}} \
148 /* A C statement (sans semicolon) to output to the stdio stream
149 FILE the assembler definition of uninitialized global DECL named
150 NAME whose size is SIZE bytes and alignment is ALIGN bytes.
151 Try to use asm_output_aligned_bss to implement this macro. */
153 #define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \
154 asm_output_aligned_bss (FILE, DECL, NAME, SIZE, ALIGN)
156 /* A C statement to output to the stdio stream FILE an assembler
157 command to advance the location counter to a multiple of 1<<LOG
158 bytes if it is within MAX_SKIP bytes.
160 This is used to align code labels according to Intel recommendations. */
162 #ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
163 #define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \
166 if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
167 else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
172 #if defined(__PIC__) && defined (USE_GNULIBC_1)
173 /* This is a kludge. The i386 GNU/Linux dynamic linker needs ___brk_addr,
174 __environ and atexit. We have to make sure they are in the .dynsym
175 section. We do this by forcing the assembler to create undefined
176 references to these symbols in the object file. */
177 #undef CRT_CALL_STATIC_FUNCTION
178 #define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC) \
179 asm (SECTION_OP "\n\t" \
180 "call " USER_LABEL_PREFIX #FUNC "\n" \
181 TEXT_SECTION_ASM_OP "\n\t" \
182 ".extern ___brk_addr\n\t" \
183 ".type ___brk_addr,@object\n\t" \
184 ".extern __environ\n\t" \
185 ".type __environ,@object\n\t" \
186 ".extern atexit\n\t" \
187 ".type atexit,@function");
190 /* Handle special EH pointer encodings. Absolute, pc-relative, and
191 indirect are handled automatically. */
192 #define ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX(FILE, ENCODING, SIZE, ADDR, DONE) \
194 if ((SIZE) == 4 && ((ENCODING) & 0x70) == DW_EH_PE_datarel) \
196 fputs (ASM_LONG, FILE); \
197 assemble_name (FILE, XSTR (ADDR, 0)); \
198 fputs (((ENCODING) & DW_EH_PE_indirect ? "@GOT" : "@GOTOFF"), FILE); \
203 /* Used by crtstuff.c to initialize the base of data-relative relocations.
204 These are GOT relative on x86, so return the pic register. */
206 #define CRT_GET_RFIB_DATA(BASE) \
208 register void *ebx_ __asm__("ebx"); \
212 #define CRT_GET_RFIB_DATA(BASE) \
213 __asm__ ("call\t.LPR%=\n" \
216 /* Due to a GAS bug, this cannot use EAX. That encodes \
217 smaller than the traditional EBX, which results in the \
218 offset being off by one. */ \
219 "addl\t$_GLOBAL_OFFSET_TABLE_+[.-.LPR%=],%0" \
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 #ifndef USE_GNULIBC_1
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 */