1/* Definitions for Intel 386 running Linux-based GNU systems with ELF format. 2 Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2001, 2002, 2004, 2005, 3 2006 Free Software Foundation, Inc. 4 Contributed by Eric Youngdale. 5 Modified for stabs-in-ELF by H.J. Lu. 6 7This file is part of GCC. 8 9GCC is free software; you can redistribute it and/or modify 10it under the terms of the GNU General Public License as published by 11the Free Software Foundation; either version 2, or (at your option) 12any later version. 13 14GCC is distributed in the hope that it will be useful, 15but WITHOUT ANY WARRANTY; without even the implied warranty of 16MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17GNU General Public License for more details. 18 19You should have received a copy of the GNU General Public License 20along with GCC; see the file COPYING. If not, write to 21the Free Software Foundation, 51 Franklin Street, Fifth Floor, 22Boston, MA 02110-1301, USA. */ 23 24/* Output at beginning of assembler file. */ 25/* The .file command should always begin the output. */ 26#define TARGET_ASM_FILE_START_FILE_DIRECTIVE true 27 28#define TARGET_VERSION fprintf (stderr, " (i386 Linux/ELF)"); 29 30/* The svr4 ABI for the i386 says that records and unions are returned 31 in memory. */ 32#undef DEFAULT_PCC_STRUCT_RETURN 33#define DEFAULT_PCC_STRUCT_RETURN 1 34 35/* We arrange for the whole %gs segment to map the tls area. */ 36#undef TARGET_TLS_DIRECT_SEG_REFS_DEFAULT 37#define TARGET_TLS_DIRECT_SEG_REFS_DEFAULT MASK_TLS_DIRECT_SEG_REFS 38 39#undef ASM_COMMENT_START 40#define ASM_COMMENT_START "#" 41 42#undef DBX_REGISTER_NUMBER 43#define DBX_REGISTER_NUMBER(n) \ 44 (TARGET_64BIT ? dbx64_register_map[n] : svr4_dbx_register_map[n]) 45 46/* Output assembler code to FILE to call the profiler. 47 To the best of my knowledge, no Linux libc has required the label 48 argument to mcount. */ 49 50#define NO_PROFILE_COUNTERS 1 51 52#undef MCOUNT_NAME 53#define MCOUNT_NAME "mcount" 54 55/* The GLIBC version of mcount for the x86 assumes that there is a 56 frame, so we cannot allow profiling without a frame pointer. */ 57 58#undef SUBTARGET_FRAME_POINTER_REQUIRED 59#define SUBTARGET_FRAME_POINTER_REQUIRED current_function_profile 60 61#undef SIZE_TYPE 62#define SIZE_TYPE "unsigned int" 63 64#undef PTRDIFF_TYPE 65#define PTRDIFF_TYPE "int" 66 67#undef WCHAR_TYPE 68#define WCHAR_TYPE "long int" 69 70#undef WCHAR_TYPE_SIZE 71#define WCHAR_TYPE_SIZE BITS_PER_WORD 72 73#define TARGET_OS_CPP_BUILTINS() \ 74 do \ 75 { \ 76 LINUX_TARGET_OS_CPP_BUILTINS(); \ 77 } \ 78 while (0) 79 80#undef CPP_SPEC 81#define CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_REENTRANT}" 82 83#undef CC1_SPEC 84#define CC1_SPEC "%(cc1_cpu) %{profile:-p}" 85 86/* Provide a LINK_SPEC appropriate for Linux. Here we provide support 87 for the special GCC options -static and -shared, which allow us to 88 link things in one of these three modes by applying the appropriate 89 combinations of options at link-time. We like to support here for 90 as many of the other GNU linker options as possible. But I don't 91 have the time to search for those flags. I am sure how to add 92 support for -soname shared_object_name. H.J. 93 94 I took out %{v:%{!V:-V}}. It is too much :-(. They can use 95 -Wl,-V. 96 97 When the -shared link option is used a final link is not being 98 done. */ 99 100/* If ELF is the default format, we should not use /lib/elf. */ 101 102/* These macros may be overridden in k*bsd-gnu.h and i386/k*bsd-gnu.h. */ 103#define LINK_EMULATION "elf_i386" 104#define GLIBC_DYNAMIC_LINKER "/lib/ld-linux.so.2" 105 106#undef SUBTARGET_EXTRA_SPECS 107#define SUBTARGET_EXTRA_SPECS \ 108 { "link_emulation", LINK_EMULATION },\ 109 { "dynamic_linker", LINUX_DYNAMIC_LINKER } 110 111#undef LINK_SPEC 112#define LINK_SPEC "-m %(link_emulation) %{shared:-shared} \ 113 %{!shared: \ 114 %{!ibcs: \ 115 %{!static: \ 116 %{rdynamic:-export-dynamic} \ 117 %{!dynamic-linker:-dynamic-linker %(dynamic_linker)}} \ 118 %{static:-static}}}" 119 120/* Similar to standard Linux, but adding -ffast-math support. */ 121#undef ENDFILE_SPEC 122#define ENDFILE_SPEC \ 123 "%{ffast-math|funsafe-math-optimizations:crtfastmath.o%s} \ 124 %{shared|pie:crtendS.o%s;:crtend.o%s} crtn.o%s" 125 126/* A C statement (sans semicolon) to output to the stdio stream 127 FILE the assembler definition of uninitialized global DECL named 128 NAME whose size is SIZE bytes and alignment is ALIGN bytes. 129 Try to use asm_output_aligned_bss to implement this macro. */ 130 131#define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \ 132 asm_output_aligned_bss (FILE, DECL, NAME, SIZE, ALIGN) 133 134/* A C statement to output to the stdio stream FILE an assembler 135 command to advance the location counter to a multiple of 1<<LOG 136 bytes if it is within MAX_SKIP bytes. 137 138 This is used to align code labels according to Intel recommendations. */ 139 140#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN 141#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \ 142 do { \ 143 if ((LOG) != 0) { \ 144 if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \ 145 else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \ 146 } \ 147 } while (0) 148#endif 149 150/* Handle special EH pointer encodings. Absolute, pc-relative, and 151 indirect are handled automatically. */ 152#define ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX(FILE, ENCODING, SIZE, ADDR, DONE) \ 153 do { \ 154 if ((SIZE) == 4 && ((ENCODING) & 0x70) == DW_EH_PE_datarel) \ 155 { \ 156 fputs (ASM_LONG, FILE); \ 157 assemble_name (FILE, XSTR (ADDR, 0)); \ 158 fputs (((ENCODING) & DW_EH_PE_indirect ? "@GOT" : "@GOTOFF"), FILE); \ 159 goto DONE; \ 160 } \ 161 } while (0) 162 163/* Used by crtstuff.c to initialize the base of data-relative relocations. 164 These are GOT relative on x86, so return the pic register. */ 165#ifdef __PIC__ 166#define CRT_GET_RFIB_DATA(BASE) \ 167 { \ 168 register void *ebx_ __asm__("ebx"); \ 169 BASE = ebx_; \ 170 } 171#else 172#define CRT_GET_RFIB_DATA(BASE) \ 173 __asm__ ("call\t.LPR%=\n" \ 174 ".LPR%=:\n\t" \ 175 "popl\t%0\n\t" \ 176 /* Due to a GAS bug, this cannot use EAX. That encodes \ 177 smaller than the traditional EBX, which results in the \ 178 offset being off by one. */ \ 179 "addl\t$_GLOBAL_OFFSET_TABLE_+[.-.LPR%=],%0" \ 180 : "=d"(BASE)) 181#endif 182 183#undef NEED_INDICATE_EXEC_STACK 184#define NEED_INDICATE_EXEC_STACK 1 185 186#define MD_UNWIND_SUPPORT "config/i386/linux-unwind.h" 187 188/* This macro may be overridden in i386/k*bsd-gnu.h. */ 189#define REG_NAME(reg) reg 190 191#ifdef TARGET_LIBC_PROVIDES_SSP 192/* i386 glibc provides __stack_chk_guard in %gs:0x14. */ 193#define TARGET_THREAD_SSP_OFFSET 0x14 194#endif 195