linux.h revision 117395
150397Sobrien/* Definitions for Intel 386 running Linux-based GNU systems with ELF format. 290075Sobrien Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2001, 2002 390075Sobrien Free Software Foundation, Inc. 418334Speter Contributed by Eric Youngdale. 518334Speter Modified for stabs-in-ELF by H.J. Lu. 618334Speter 718334SpeterThis file is part of GNU CC. 818334Speter 918334SpeterGNU CC is free software; you can redistribute it and/or modify 1018334Speterit under the terms of the GNU General Public License as published by 1118334Speterthe Free Software Foundation; either version 2, or (at your option) 1218334Speterany later version. 1318334Speter 1418334SpeterGNU CC is distributed in the hope that it will be useful, 1518334Speterbut WITHOUT ANY WARRANTY; without even the implied warranty of 1618334SpeterMERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 1718334SpeterGNU General Public License for more details. 1818334Speter 1918334SpeterYou should have received a copy of the GNU General Public License 2018334Speteralong with GNU CC; see the file COPYING. If not, write to 2118334Speterthe Free Software Foundation, 59 Temple Place - Suite 330, 2218334SpeterBoston, MA 02111-1307, USA. */ 2318334Speter 2418334Speter#define LINUX_DEFAULT_ELF 2518334Speter 2690075Sobrien/* Output at beginning of assembler file. */ 2790075Sobrien/* The .file command should always begin the output. */ 2890075Sobrien#undef ASM_FILE_START 2990075Sobrien#define ASM_FILE_START(FILE) \ 3090075Sobrien do { \ 3190075Sobrien output_file_directive (FILE, main_input_filename); \ 3290075Sobrien if (ix86_asm_dialect == ASM_INTEL) \ 3390075Sobrien fputs ("\t.intel_syntax\n", FILE); \ 3490075Sobrien } while (0) 3518334Speter 3618334Speter#define TARGET_VERSION fprintf (stderr, " (i386 Linux/ELF)"); 3718334Speter 3818334Speter/* The svr4 ABI for the i386 says that records and unions are returned 3918334Speter in memory. */ 4018334Speter#undef DEFAULT_PCC_STRUCT_RETURN 4118334Speter#define DEFAULT_PCC_STRUCT_RETURN 1 4218334Speter 4350397Sobrien#undef ASM_COMMENT_START 4450397Sobrien#define ASM_COMMENT_START "#" 4550397Sobrien 4618334Speter#undef DBX_REGISTER_NUMBER 4718334Speter#define DBX_REGISTER_NUMBER(n) \ 4890075Sobrien (TARGET_64BIT ? dbx64_register_map[n] : svr4_dbx_register_map[n]) 4918334Speter 5090075Sobrien/* Output assembler code to FILE to call the profiler. 5190075Sobrien To the best of my knowledge, no Linux libc has required the label 5290075Sobrien argument to mcount. */ 5318334Speter 5490075Sobrien#define NO_PROFILE_COUNTERS 5590075Sobrien 56117395Skan#undef MCOUNT_NAME 57117395Skan#define MCOUNT_NAME "mcount" 5818334Speter 59117395Skan/* The GLIBC version of mcount for the x86 assumes that there is a 6090075Sobrien frame, so we cannot allow profiling without a frame pointer. */ 6190075Sobrien 62117395Skan#undef SUBTARGET_FRAME_POINTER_REQUIRED 63117395Skan#define SUBTARGET_FRAME_POINTER_REQUIRED current_function_profile 6490075Sobrien 6518334Speter#undef SIZE_TYPE 6618334Speter#define SIZE_TYPE "unsigned int" 6718334Speter 6818334Speter#undef PTRDIFF_TYPE 6918334Speter#define PTRDIFF_TYPE "int" 7018334Speter 7118334Speter#undef WCHAR_TYPE 7218334Speter#define WCHAR_TYPE "long int" 7318334Speter 7418334Speter#undef WCHAR_TYPE_SIZE 7518334Speter#define WCHAR_TYPE_SIZE BITS_PER_WORD 7618334Speter 77117395Skan#define TARGET_OS_CPP_BUILTINS() \ 78117395Skan do \ 79117395Skan { \ 80117395Skan builtin_define_std ("linux"); \ 81117395Skan builtin_define_std ("unix"); \ 82117395Skan builtin_define ("__ELF__"); \ 83117395Skan builtin_define ("__gnu_linux__"); \ 84117395Skan builtin_assert ("system=posix"); \ 85117395Skan if (flag_pic) \ 86117395Skan { \ 87117395Skan builtin_define ("__PIC__"); \ 88117395Skan builtin_define ("__pic__"); \ 89117395Skan } \ 90117395Skan } \ 91117395Skan while (0) 9218334Speter 9318334Speter#undef CPP_SPEC 9448743Sobrien#ifdef USE_GNULIBC_1 95117395Skan#define CPP_SPEC "%{posix:-D_POSIX_SOURCE}" 9618334Speter#else 97117395Skan#define CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_REENTRANT}" 9818334Speter#endif 9918334Speter 10050397Sobrien#undef CC1_SPEC 10150397Sobrien#define CC1_SPEC "%(cc1_cpu) %{profile:-p}" 10248743Sobrien 10318334Speter/* Provide a LINK_SPEC appropriate for Linux. Here we provide support 10418334Speter for the special GCC options -static and -shared, which allow us to 10518334Speter link things in one of these three modes by applying the appropriate 10618334Speter combinations of options at link-time. We like to support here for 10718334Speter as many of the other GNU linker options as possible. But I don't 10818334Speter have the time to search for those flags. I am sure how to add 10918334Speter support for -soname shared_object_name. H.J. 11018334Speter 11118334Speter I took out %{v:%{!V:-V}}. It is too much :-(. They can use 11218334Speter -Wl,-V. 11318334Speter 11418334Speter When the -shared link option is used a final link is not being 11518334Speter done. */ 11618334Speter 11790075Sobrien/* If ELF is the default format, we should not use /lib/elf. */ 11818334Speter 11918334Speter#undef LINK_SPEC 12048743Sobrien#ifdef USE_GNULIBC_1 12118334Speter#ifndef LINUX_DEFAULT_ELF 12218334Speter#define LINK_SPEC "-m elf_i386 %{shared:-shared} \ 12318334Speter %{!shared: \ 12418334Speter %{!ibcs: \ 12518334Speter %{!static: \ 12618334Speter %{rdynamic:-export-dynamic} \ 12718334Speter %{!dynamic-linker:-dynamic-linker /lib/elf/ld-linux.so.1} \ 12818334Speter %{!rpath:-rpath /lib/elf/}} %{static:-static}}}" 12918334Speter#else 13018334Speter#define LINK_SPEC "-m elf_i386 %{shared:-shared} \ 13118334Speter %{!shared: \ 13218334Speter %{!ibcs: \ 13318334Speter %{!static: \ 13418334Speter %{rdynamic:-export-dynamic} \ 13518334Speter %{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.1}} \ 13618334Speter %{static:-static}}}" 13718334Speter#endif 13850397Sobrien#else 13948743Sobrien#define LINK_SPEC "-m elf_i386 %{shared:-shared} \ 14048743Sobrien %{!shared: \ 14148743Sobrien %{!ibcs: \ 14248743Sobrien %{!static: \ 14348743Sobrien %{rdynamic:-export-dynamic} \ 14448743Sobrien %{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.2}} \ 14548743Sobrien %{static:-static}}}" 14650397Sobrien#endif 14718334Speter 14850397Sobrien/* A C statement (sans semicolon) to output to the stdio stream 14950397Sobrien FILE the assembler definition of uninitialized global DECL named 15050397Sobrien NAME whose size is SIZE bytes and alignment is ALIGN bytes. 15150397Sobrien Try to use asm_output_aligned_bss to implement this macro. */ 15250397Sobrien 15350397Sobrien#define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \ 15450397Sobrien asm_output_aligned_bss (FILE, DECL, NAME, SIZE, ALIGN) 15550397Sobrien 15650397Sobrien/* A C statement to output to the stdio stream FILE an assembler 15750397Sobrien command to advance the location counter to a multiple of 1<<LOG 15850397Sobrien bytes if it is within MAX_SKIP bytes. 15950397Sobrien 16050397Sobrien This is used to align code labels according to Intel recommendations. */ 16150397Sobrien 16250397Sobrien#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN 16352284Sobrien#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \ 16452284Sobrien do { \ 16552284Sobrien if ((LOG) != 0) { \ 16652284Sobrien if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \ 16752284Sobrien else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \ 16852284Sobrien } \ 16952284Sobrien } while (0) 17050397Sobrien#endif 17190075Sobrien 17290075Sobrien#if defined(__PIC__) && defined (USE_GNULIBC_1) 17390075Sobrien/* This is a kludge. The i386 GNU/Linux dynamic linker needs ___brk_addr, 17490075Sobrien __environ and atexit. We have to make sure they are in the .dynsym 17590075Sobrien section. We do this by forcing the assembler to create undefined 17690075Sobrien references to these symbols in the object file. */ 17790075Sobrien#undef CRT_CALL_STATIC_FUNCTION 17890075Sobrien#define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC) \ 17990075Sobrien asm (SECTION_OP "\n\t" \ 18090075Sobrien "call " USER_LABEL_PREFIX #FUNC "\n" \ 18190075Sobrien TEXT_SECTION_ASM_OP "\n\t" \ 18290075Sobrien ".extern ___brk_addr\n\t" \ 18390075Sobrien ".type ___brk_addr,@object\n\t" \ 18490075Sobrien ".extern __environ\n\t" \ 18590075Sobrien ".type __environ,@object\n\t" \ 18690075Sobrien ".extern atexit\n\t" \ 18790075Sobrien ".type atexit,@function"); 18890075Sobrien#endif 18990075Sobrien 19090075Sobrien/* Handle special EH pointer encodings. Absolute, pc-relative, and 19190075Sobrien indirect are handled automatically. */ 19290075Sobrien#define ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX(FILE, ENCODING, SIZE, ADDR, DONE) \ 19390075Sobrien do { \ 19490075Sobrien if ((SIZE) == 4 && ((ENCODING) & 0x70) == DW_EH_PE_datarel) \ 19590075Sobrien { \ 19690075Sobrien fputs (ASM_LONG, FILE); \ 19790075Sobrien assemble_name (FILE, XSTR (ADDR, 0)); \ 19890075Sobrien fputs (((ENCODING) & DW_EH_PE_indirect ? "@GOT" : "@GOTOFF"), FILE); \ 19990075Sobrien goto DONE; \ 20090075Sobrien } \ 20190075Sobrien } while (0) 20290075Sobrien 20390075Sobrien/* Used by crtstuff.c to initialize the base of data-relative relocations. 20490075Sobrien These are GOT relative on x86, so return the pic register. */ 20590075Sobrien#ifdef __PIC__ 20690075Sobrien#define CRT_GET_RFIB_DATA(BASE) \ 20790075Sobrien { \ 20890075Sobrien register void *ebx_ __asm__("ebx"); \ 20990075Sobrien BASE = ebx_; \ 21090075Sobrien } 21190075Sobrien#else 21290075Sobrien#define CRT_GET_RFIB_DATA(BASE) \ 21390075Sobrien __asm__ ("call\t.LPR%=\n" \ 21490075Sobrien ".LPR%=:\n\t" \ 21590075Sobrien "popl\t%0\n\t" \ 21690075Sobrien /* Due to a GAS bug, this cannot use EAX. That encodes \ 21790075Sobrien smaller than the traditional EBX, which results in the \ 21890075Sobrien offset being off by one. */ \ 21990075Sobrien "addl\t$_GLOBAL_OFFSET_TABLE_+[.-.LPR%=],%0" \ 22090075Sobrien : "=d"(BASE)) 22190075Sobrien#endif 22290075Sobrien 22390075Sobrien/* Do code reading to identify a signal frame, and set the frame 22490075Sobrien state data appropriately. See unwind-dw2.c for the structs. */ 22590075Sobrien 22690075Sobrien#ifdef IN_LIBGCC2 227117395Skan/* There's no sys/ucontext.h for some (all?) libc1, so no 228117395Skan signal-turned-exceptions for them. There's also no configure-run for 229117395Skan the target, so we can't check on (e.g.) HAVE_SYS_UCONTEXT_H. Using the 230117395Skan target libc1 macro should be enough. */ 231117395Skan#ifndef USE_GNULIBC_1 23290075Sobrien#include <signal.h> 23390075Sobrien#include <sys/ucontext.h> 23490075Sobrien 23590075Sobrien#define MD_FALLBACK_FRAME_STATE_FOR(CONTEXT, FS, SUCCESS) \ 23690075Sobrien do { \ 23790075Sobrien unsigned char *pc_ = (CONTEXT)->ra; \ 23890075Sobrien struct sigcontext *sc_; \ 23990075Sobrien long new_cfa_; \ 24090075Sobrien \ 24190075Sobrien /* popl %eax ; movl $__NR_sigreturn,%eax ; int $0x80 */ \ 24290075Sobrien if (*(unsigned short *)(pc_+0) == 0xb858 \ 24390075Sobrien && *(unsigned int *)(pc_+2) == 119 \ 24490075Sobrien && *(unsigned short *)(pc_+6) == 0x80cd) \ 24590075Sobrien sc_ = (CONTEXT)->cfa + 4; \ 24690075Sobrien /* movl $__NR_rt_sigreturn,%eax ; int $0x80 */ \ 24790075Sobrien else if (*(unsigned char *)(pc_+0) == 0xb8 \ 24890075Sobrien && *(unsigned int *)(pc_+1) == 173 \ 24990075Sobrien && *(unsigned short *)(pc_+5) == 0x80cd) \ 25090075Sobrien { \ 25190075Sobrien struct rt_sigframe { \ 25290075Sobrien int sig; \ 25390075Sobrien struct siginfo *pinfo; \ 25490075Sobrien void *puc; \ 25590075Sobrien struct siginfo info; \ 25690075Sobrien struct ucontext uc; \ 25790075Sobrien } *rt_ = (CONTEXT)->cfa; \ 25890075Sobrien sc_ = (struct sigcontext *) &rt_->uc.uc_mcontext; \ 25990075Sobrien } \ 26090075Sobrien else \ 26190075Sobrien break; \ 26290075Sobrien \ 26390075Sobrien new_cfa_ = sc_->esp; \ 26490075Sobrien (FS)->cfa_how = CFA_REG_OFFSET; \ 26590075Sobrien (FS)->cfa_reg = 4; \ 26690075Sobrien (FS)->cfa_offset = new_cfa_ - (long) (CONTEXT)->cfa; \ 26790075Sobrien \ 26890075Sobrien /* The SVR4 register numbering macros aren't usable in libgcc. */ \ 26990075Sobrien (FS)->regs.reg[0].how = REG_SAVED_OFFSET; \ 27090075Sobrien (FS)->regs.reg[0].loc.offset = (long)&sc_->eax - new_cfa_; \ 27190075Sobrien (FS)->regs.reg[3].how = REG_SAVED_OFFSET; \ 27290075Sobrien (FS)->regs.reg[3].loc.offset = (long)&sc_->ebx - new_cfa_; \ 27390075Sobrien (FS)->regs.reg[1].how = REG_SAVED_OFFSET; \ 27490075Sobrien (FS)->regs.reg[1].loc.offset = (long)&sc_->ecx - new_cfa_; \ 27590075Sobrien (FS)->regs.reg[2].how = REG_SAVED_OFFSET; \ 27690075Sobrien (FS)->regs.reg[2].loc.offset = (long)&sc_->edx - new_cfa_; \ 27790075Sobrien (FS)->regs.reg[6].how = REG_SAVED_OFFSET; \ 27890075Sobrien (FS)->regs.reg[6].loc.offset = (long)&sc_->esi - new_cfa_; \ 27990075Sobrien (FS)->regs.reg[7].how = REG_SAVED_OFFSET; \ 28090075Sobrien (FS)->regs.reg[7].loc.offset = (long)&sc_->edi - new_cfa_; \ 28190075Sobrien (FS)->regs.reg[5].how = REG_SAVED_OFFSET; \ 28290075Sobrien (FS)->regs.reg[5].loc.offset = (long)&sc_->ebp - new_cfa_; \ 28390075Sobrien (FS)->regs.reg[8].how = REG_SAVED_OFFSET; \ 28490075Sobrien (FS)->regs.reg[8].loc.offset = (long)&sc_->eip - new_cfa_; \ 28590075Sobrien (FS)->retaddr_column = 8; \ 28690075Sobrien goto SUCCESS; \ 28790075Sobrien } while (0) 288117395Skan#endif /* not USE_GNULIBC_1 */ 289117395Skan#endif /* IN_LIBGCC2 */ 290