linux.h revision 132718
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 7132718SkanThis file is part of GCC. 818334Speter 9132718SkanGCC 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 14132718SkanGCC 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 20132718Skanalong with GCC; see the file COPYING. If not, write to 2118334Speterthe Free Software Foundation, 59 Temple Place - Suite 330, 2218334SpeterBoston, MA 02111-1307, USA. */ 2318334Speter 2490075Sobrien/* Output at beginning of assembler file. */ 2590075Sobrien/* The .file command should always begin the output. */ 26132718Skan#define TARGET_ASM_FILE_START_FILE_DIRECTIVE true 2718334Speter 2818334Speter#define TARGET_VERSION fprintf (stderr, " (i386 Linux/ELF)"); 2918334Speter 3018334Speter/* The svr4 ABI for the i386 says that records and unions are returned 3118334Speter in memory. */ 3218334Speter#undef DEFAULT_PCC_STRUCT_RETURN 3318334Speter#define DEFAULT_PCC_STRUCT_RETURN 1 3418334Speter 35132718Skan/* We arrange for the whole %gs segment to map the tls area. */ 36132718Skan#undef TARGET_TLS_DIRECT_SEG_REFS_DEFAULT 37132718Skan#define TARGET_TLS_DIRECT_SEG_REFS_DEFAULT MASK_TLS_DIRECT_SEG_REFS 38132718Skan 3950397Sobrien#undef ASM_COMMENT_START 4050397Sobrien#define ASM_COMMENT_START "#" 4150397Sobrien 4218334Speter#undef DBX_REGISTER_NUMBER 4318334Speter#define DBX_REGISTER_NUMBER(n) \ 4490075Sobrien (TARGET_64BIT ? dbx64_register_map[n] : svr4_dbx_register_map[n]) 4518334Speter 4690075Sobrien/* Output assembler code to FILE to call the profiler. 4790075Sobrien To the best of my knowledge, no Linux libc has required the label 4890075Sobrien argument to mcount. */ 4918334Speter 50132718Skan#define NO_PROFILE_COUNTERS 1 5190075Sobrien 52117395Skan#undef MCOUNT_NAME 53117395Skan#define MCOUNT_NAME "mcount" 5418334Speter 55117395Skan/* The GLIBC version of mcount for the x86 assumes that there is a 5690075Sobrien frame, so we cannot allow profiling without a frame pointer. */ 5790075Sobrien 58117395Skan#undef SUBTARGET_FRAME_POINTER_REQUIRED 59117395Skan#define SUBTARGET_FRAME_POINTER_REQUIRED current_function_profile 6090075Sobrien 6118334Speter#undef SIZE_TYPE 6218334Speter#define SIZE_TYPE "unsigned int" 6318334Speter 6418334Speter#undef PTRDIFF_TYPE 6518334Speter#define PTRDIFF_TYPE "int" 6618334Speter 6718334Speter#undef WCHAR_TYPE 6818334Speter#define WCHAR_TYPE "long int" 6918334Speter 7018334Speter#undef WCHAR_TYPE_SIZE 7118334Speter#define WCHAR_TYPE_SIZE BITS_PER_WORD 7218334Speter 73117395Skan#define TARGET_OS_CPP_BUILTINS() \ 74117395Skan do \ 75117395Skan { \ 76132718Skan LINUX_TARGET_OS_CPP_BUILTINS(); \ 77117395Skan if (flag_pic) \ 78117395Skan { \ 79117395Skan builtin_define ("__PIC__"); \ 80117395Skan builtin_define ("__pic__"); \ 81117395Skan } \ 82117395Skan } \ 83117395Skan while (0) 8418334Speter 8518334Speter#undef CPP_SPEC 8648743Sobrien#ifdef USE_GNULIBC_1 87117395Skan#define CPP_SPEC "%{posix:-D_POSIX_SOURCE}" 8818334Speter#else 89117395Skan#define CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{pthread:-D_REENTRANT}" 9018334Speter#endif 9118334Speter 9250397Sobrien#undef CC1_SPEC 9350397Sobrien#define CC1_SPEC "%(cc1_cpu) %{profile:-p}" 9448743Sobrien 9518334Speter/* Provide a LINK_SPEC appropriate for Linux. Here we provide support 9618334Speter for the special GCC options -static and -shared, which allow us to 9718334Speter link things in one of these three modes by applying the appropriate 9818334Speter combinations of options at link-time. We like to support here for 9918334Speter as many of the other GNU linker options as possible. But I don't 10018334Speter have the time to search for those flags. I am sure how to add 10118334Speter support for -soname shared_object_name. H.J. 10218334Speter 10318334Speter I took out %{v:%{!V:-V}}. It is too much :-(. They can use 10418334Speter -Wl,-V. 10518334Speter 10618334Speter When the -shared link option is used a final link is not being 10718334Speter done. */ 10818334Speter 10990075Sobrien/* If ELF is the default format, we should not use /lib/elf. */ 11018334Speter 11118334Speter#undef LINK_SPEC 11248743Sobrien#ifdef USE_GNULIBC_1 11318334Speter#define LINK_SPEC "-m elf_i386 %{shared:-shared} \ 11418334Speter %{!shared: \ 11518334Speter %{!ibcs: \ 11618334Speter %{!static: \ 11718334Speter %{rdynamic:-export-dynamic} \ 11818334Speter %{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.1}} \ 11918334Speter %{static:-static}}}" 12050397Sobrien#else 12148743Sobrien#define LINK_SPEC "-m elf_i386 %{shared:-shared} \ 12248743Sobrien %{!shared: \ 12348743Sobrien %{!ibcs: \ 12448743Sobrien %{!static: \ 12548743Sobrien %{rdynamic:-export-dynamic} \ 12648743Sobrien %{!dynamic-linker:-dynamic-linker /lib/ld-linux.so.2}} \ 12748743Sobrien %{static:-static}}}" 12850397Sobrien#endif 12918334Speter 13050397Sobrien/* A C statement (sans semicolon) to output to the stdio stream 13150397Sobrien FILE the assembler definition of uninitialized global DECL named 13250397Sobrien NAME whose size is SIZE bytes and alignment is ALIGN bytes. 13350397Sobrien Try to use asm_output_aligned_bss to implement this macro. */ 13450397Sobrien 13550397Sobrien#define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \ 13650397Sobrien asm_output_aligned_bss (FILE, DECL, NAME, SIZE, ALIGN) 13750397Sobrien 13850397Sobrien/* A C statement to output to the stdio stream FILE an assembler 13950397Sobrien command to advance the location counter to a multiple of 1<<LOG 14050397Sobrien bytes if it is within MAX_SKIP bytes. 14150397Sobrien 14250397Sobrien This is used to align code labels according to Intel recommendations. */ 14350397Sobrien 14450397Sobrien#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN 14552284Sobrien#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \ 14652284Sobrien do { \ 14752284Sobrien if ((LOG) != 0) { \ 14852284Sobrien if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \ 14952284Sobrien else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \ 15052284Sobrien } \ 15152284Sobrien } while (0) 15250397Sobrien#endif 15390075Sobrien 15490075Sobrien#if defined(__PIC__) && defined (USE_GNULIBC_1) 15590075Sobrien/* This is a kludge. The i386 GNU/Linux dynamic linker needs ___brk_addr, 15690075Sobrien __environ and atexit. We have to make sure they are in the .dynsym 15790075Sobrien section. We do this by forcing the assembler to create undefined 15890075Sobrien references to these symbols in the object file. */ 15990075Sobrien#undef CRT_CALL_STATIC_FUNCTION 16090075Sobrien#define CRT_CALL_STATIC_FUNCTION(SECTION_OP, FUNC) \ 16190075Sobrien asm (SECTION_OP "\n\t" \ 16290075Sobrien "call " USER_LABEL_PREFIX #FUNC "\n" \ 16390075Sobrien TEXT_SECTION_ASM_OP "\n\t" \ 16490075Sobrien ".extern ___brk_addr\n\t" \ 16590075Sobrien ".type ___brk_addr,@object\n\t" \ 16690075Sobrien ".extern __environ\n\t" \ 16790075Sobrien ".type __environ,@object\n\t" \ 16890075Sobrien ".extern atexit\n\t" \ 16990075Sobrien ".type atexit,@function"); 17090075Sobrien#endif 17190075Sobrien 17290075Sobrien/* Handle special EH pointer encodings. Absolute, pc-relative, and 17390075Sobrien indirect are handled automatically. */ 17490075Sobrien#define ASM_MAYBE_OUTPUT_ENCODED_ADDR_RTX(FILE, ENCODING, SIZE, ADDR, DONE) \ 17590075Sobrien do { \ 17690075Sobrien if ((SIZE) == 4 && ((ENCODING) & 0x70) == DW_EH_PE_datarel) \ 17790075Sobrien { \ 17890075Sobrien fputs (ASM_LONG, FILE); \ 17990075Sobrien assemble_name (FILE, XSTR (ADDR, 0)); \ 18090075Sobrien fputs (((ENCODING) & DW_EH_PE_indirect ? "@GOT" : "@GOTOFF"), FILE); \ 18190075Sobrien goto DONE; \ 18290075Sobrien } \ 18390075Sobrien } while (0) 18490075Sobrien 18590075Sobrien/* Used by crtstuff.c to initialize the base of data-relative relocations. 18690075Sobrien These are GOT relative on x86, so return the pic register. */ 18790075Sobrien#ifdef __PIC__ 18890075Sobrien#define CRT_GET_RFIB_DATA(BASE) \ 18990075Sobrien { \ 19090075Sobrien register void *ebx_ __asm__("ebx"); \ 19190075Sobrien BASE = ebx_; \ 19290075Sobrien } 19390075Sobrien#else 19490075Sobrien#define CRT_GET_RFIB_DATA(BASE) \ 19590075Sobrien __asm__ ("call\t.LPR%=\n" \ 19690075Sobrien ".LPR%=:\n\t" \ 19790075Sobrien "popl\t%0\n\t" \ 19890075Sobrien /* Due to a GAS bug, this cannot use EAX. That encodes \ 19990075Sobrien smaller than the traditional EBX, which results in the \ 20090075Sobrien offset being off by one. */ \ 20190075Sobrien "addl\t$_GLOBAL_OFFSET_TABLE_+[.-.LPR%=],%0" \ 20290075Sobrien : "=d"(BASE)) 20390075Sobrien#endif 20490075Sobrien 205132718Skan#undef NEED_INDICATE_EXEC_STACK 206132718Skan#define NEED_INDICATE_EXEC_STACK 1 207132718Skan 20890075Sobrien/* Do code reading to identify a signal frame, and set the frame 20990075Sobrien state data appropriately. See unwind-dw2.c for the structs. */ 21090075Sobrien 21190075Sobrien#ifdef IN_LIBGCC2 212117395Skan/* There's no sys/ucontext.h for some (all?) libc1, so no 213117395Skan signal-turned-exceptions for them. There's also no configure-run for 214117395Skan the target, so we can't check on (e.g.) HAVE_SYS_UCONTEXT_H. Using the 215117395Skan target libc1 macro should be enough. */ 216132718Skan#if !(defined (USE_GNULIBC_1) || (__GLIBC__ == 2 && __GLIBC_MINOR__ == 0)) 21790075Sobrien#include <signal.h> 21890075Sobrien#include <sys/ucontext.h> 21990075Sobrien 22090075Sobrien#define MD_FALLBACK_FRAME_STATE_FOR(CONTEXT, FS, SUCCESS) \ 22190075Sobrien do { \ 22290075Sobrien unsigned char *pc_ = (CONTEXT)->ra; \ 22390075Sobrien struct sigcontext *sc_; \ 22490075Sobrien long new_cfa_; \ 22590075Sobrien \ 22690075Sobrien /* popl %eax ; movl $__NR_sigreturn,%eax ; int $0x80 */ \ 22790075Sobrien if (*(unsigned short *)(pc_+0) == 0xb858 \ 22890075Sobrien && *(unsigned int *)(pc_+2) == 119 \ 22990075Sobrien && *(unsigned short *)(pc_+6) == 0x80cd) \ 23090075Sobrien sc_ = (CONTEXT)->cfa + 4; \ 23190075Sobrien /* movl $__NR_rt_sigreturn,%eax ; int $0x80 */ \ 23290075Sobrien else if (*(unsigned char *)(pc_+0) == 0xb8 \ 23390075Sobrien && *(unsigned int *)(pc_+1) == 173 \ 23490075Sobrien && *(unsigned short *)(pc_+5) == 0x80cd) \ 23590075Sobrien { \ 23690075Sobrien struct rt_sigframe { \ 23790075Sobrien int sig; \ 23890075Sobrien struct siginfo *pinfo; \ 23990075Sobrien void *puc; \ 24090075Sobrien struct siginfo info; \ 24190075Sobrien struct ucontext uc; \ 24290075Sobrien } *rt_ = (CONTEXT)->cfa; \ 24390075Sobrien sc_ = (struct sigcontext *) &rt_->uc.uc_mcontext; \ 24490075Sobrien } \ 24590075Sobrien else \ 24690075Sobrien break; \ 24790075Sobrien \ 24890075Sobrien new_cfa_ = sc_->esp; \ 24990075Sobrien (FS)->cfa_how = CFA_REG_OFFSET; \ 25090075Sobrien (FS)->cfa_reg = 4; \ 25190075Sobrien (FS)->cfa_offset = new_cfa_ - (long) (CONTEXT)->cfa; \ 25290075Sobrien \ 25390075Sobrien /* The SVR4 register numbering macros aren't usable in libgcc. */ \ 25490075Sobrien (FS)->regs.reg[0].how = REG_SAVED_OFFSET; \ 25590075Sobrien (FS)->regs.reg[0].loc.offset = (long)&sc_->eax - new_cfa_; \ 25690075Sobrien (FS)->regs.reg[3].how = REG_SAVED_OFFSET; \ 25790075Sobrien (FS)->regs.reg[3].loc.offset = (long)&sc_->ebx - new_cfa_; \ 25890075Sobrien (FS)->regs.reg[1].how = REG_SAVED_OFFSET; \ 25990075Sobrien (FS)->regs.reg[1].loc.offset = (long)&sc_->ecx - new_cfa_; \ 26090075Sobrien (FS)->regs.reg[2].how = REG_SAVED_OFFSET; \ 26190075Sobrien (FS)->regs.reg[2].loc.offset = (long)&sc_->edx - new_cfa_; \ 26290075Sobrien (FS)->regs.reg[6].how = REG_SAVED_OFFSET; \ 26390075Sobrien (FS)->regs.reg[6].loc.offset = (long)&sc_->esi - new_cfa_; \ 26490075Sobrien (FS)->regs.reg[7].how = REG_SAVED_OFFSET; \ 26590075Sobrien (FS)->regs.reg[7].loc.offset = (long)&sc_->edi - new_cfa_; \ 26690075Sobrien (FS)->regs.reg[5].how = REG_SAVED_OFFSET; \ 26790075Sobrien (FS)->regs.reg[5].loc.offset = (long)&sc_->ebp - new_cfa_; \ 26890075Sobrien (FS)->regs.reg[8].how = REG_SAVED_OFFSET; \ 26990075Sobrien (FS)->regs.reg[8].loc.offset = (long)&sc_->eip - new_cfa_; \ 27090075Sobrien (FS)->retaddr_column = 8; \ 27190075Sobrien goto SUCCESS; \ 27290075Sobrien } while (0) 273117395Skan#endif /* not USE_GNULIBC_1 */ 274117395Skan#endif /* IN_LIBGCC2 */ 275