elf.h

linux下的gcc编译器

/* Definitions for ELF assembler support.
   Copyright (C) 1999 Free Software Foundation, Inc.

This file is part of GNU CC.

GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU CC is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

/* So we can conditionalize small amounts of code in pa.c or pa.md.  */
#define OBJ_ELF

#define ENDFILE_SPEC "crtend.o%s"

#define STARTFILE_SPEC "%{!shared: \
			 %{!symbolic: \
			  %{pg:gcrt0.o%s}%{!pg:%{p:mcrt0.o%s}%{!p:crt0.o%s}}}}\
			crtbegin.o%s"

#define TEXT_SECTION_ASM_OP "\t.text"
#define DATA_SECTION_ASM_OP "\t.data"
#define BSS_SECTION_ASM_OP "\t.section\t.bss"

#undef ASM_FILE_START
#define ASM_FILE_START(FILE) \
do {  \
     if (TARGET_PA_20) \
       fputs("\t.LEVEL 2.0\n", FILE); \
     else if (TARGET_PA_11) \
       fputs("\t.LEVEL 1.1\n", FILE); \
     else \
       fputs("\t.LEVEL 1.0\n", FILE); \
     if (profile_flag)\
       fprintf (FILE, "\t.IMPORT _mcount, ENTRY\n");\
     if (write_symbols != NO_DEBUG) \
       output_file_directive ((FILE), main_input_filename); \
   } while (0)

#undef ASM_DECLARE_FUNCTION_NAME
#define ASM_DECLARE_FUNCTION_NAME(FILE, NAME, DECL) \
do {  \
  if (TREE_PUBLIC (DECL)) \
    { \
      fputs ("\t.EXPORT ", FILE); \
      assemble_name (FILE, NAME); \
      fputs (",ENTRY\n", FILE); \
    } \
   } while (0)

/* This is how to output a command to make the user-level label named NAME
   defined for reference from other files.

   We call assemble_name, which in turn sets TREE_SYMBOL_REFERENCED.  This
   macro will restore the original value of TREE_SYMBOL_REFERENCED to avoid
   placing useless function definitions in the output file.

   Also note that the SOM based tools need the symbol imported as a CODE
   symbol, while the ELF based tools require the symbol to be imported as
   an ENTRY symbol.  What a crock.  */

#define ASM_OUTPUT_EXTERNAL(FILE, DECL, NAME)	\
  do { int save_referenced;					\
       save_referenced = TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (DECL)); \
       fputs ("\t.IMPORT ", FILE);					\
	 assemble_name (FILE, NAME);				\
       if (FUNCTION_NAME_P (NAME))     				\
	 fputs (",ENTRY\n", FILE);				\
       else							\
	 fputs (",DATA\n", FILE);				\
       TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (DECL)) = save_referenced; \
     } while (0)

/* The bogus HP assembler requires ALL external references to be
   "imported", even library calls. They look a bit different, so
   here's this macro.

   Also note not all libcall names are passed to
   targetm.encode_section_info (__main for example).  To make sure all
   libcall names have section info recorded in them, we do it here.  */

#undef ASM_OUTPUT_EXTERNAL_LIBCALL
#define ASM_OUTPUT_EXTERNAL_LIBCALL(FILE, RTL) \
  do { fputs ("\t.IMPORT ", FILE);					\
       if (!function_label_operand (RTL, VOIDmode))			\
	 hppa_encode_label (RTL);					\
       assemble_name (FILE, XSTR ((RTL), 0));		       		\
       fputs (",ENTRY\n", FILE);					\
     } while (0)

/* Biggest alignment supported by the object file format of this
   machine.  Use this macro to limit the alignment which can be
   specified using the `__attribute__ ((aligned (N)))' construct.  If
   not defined, the default value is `BIGGEST_ALIGNMENT'.  */
#define MAX_OFILE_ALIGNMENT (32768 * 8)