xref: /freebsd-11.0-release/contrib/gcc/config/i386/freebsd.h

/* Definitions for Intel 386 running FreeBSD with either a.out or ELF format
   Copyright (C) 1996-2000 Free Software Foundation, Inc.
   Contributed by Eric Youngdale.
   Modified for stabs-in-ELF by H.J. Lu.
   Adapted from GNU/Linux version by John Polstra.
   Added support for generating "old a.out gas" on the fly by Peter Wemm.
   Continued development by David O'Brien <obrien@freebsd.org>

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.  */

/* $FreeBSD: head/contrib/gcc/config/i386/freebsd.h 95348 2002-04-24 04:48:00Z obrien $ */

#undef  CPP_PREDEFINES
#define CPP_PREDEFINES 							\
  "-Di386 -Acpu(i386) -Amachine(i386)"					\
  FBSD_CPP_PREDEFINES

#undef  CC1_SPEC
#define CC1_SPEC "\
  %{gline:%{!g:%{!g0:%{!g1:%{!g2: -g1}}}}} \
  %{maout: %{!mno-underscores: %{!munderscores: -munderscores }}}"

#undef  ASM_SPEC
#define ASM_SPEC	"%{v*: -v} %{maout: %{fpic:-k} %{fPIC:-k}}"

#undef  ASM_FINAL_SPEC
#define ASM_FINAL_SPEC	"%|"

/* Provide a LINK_SPEC appropriate for FreeBSD.  Here we provide support
   for the special GCC options -static and -shared, which allow us to
   link things in one of these three modes by applying the appropriate
   combinations of options at link-time. We like to support here for
   as many of the other GNU linker options as possible. But I don't
   have the time to search for those flags. I am sure how to add
   support for -soname shared_object_name. H.J.

   I took out %{v:%{!V:-V}}. It is too much :-(. They can use
   -Wl,-V.

   When the -shared link option is used a final link is not being
   done.  */

#undef	LINK_SPEC
#define LINK_SPEC "\
 %{p:%e`-p' not supported; use `-pg' and gprof(1)} \
  %{maout: %{shared:-Bshareable} \
    %{!shared:%{!nostdlib:%{!r:%{!e*:-e start}}} -dc -dp %{static:-Bstatic} \
      %{pg:-Bstatic} %{Z}} \
    %{assert*} %{R*}} \
  %{!maout: \
    %{Wl,*:%*} \
    %{assert*} %{R*} %{rpath*} %{defsym*} \
    %{shared:-Bshareable %{h*} %{soname*}} \
    %{symbolic:-Bsymbolic} \
    %{!shared: \
      %{!static: \
	%{rdynamic: -export-dynamic} \
	%{!dynamic-linker: -dynamic-linker /usr/libexec/ld-elf.so.1}} \
      %{static:-Bstatic}}}"

#undef STARTFILE_SPEC
#define STARTFILE_SPEC "\
  %{maout: %{shared:c++rt0.o%s} \
    %{!shared: \
      %{pg:gcrt0.o%s}%{!pg: \
	%{static:scrt0.o%s} \
	%{!static:crt0.o%s}}}} \
  %{!maout: \
    %{!shared: \
      %{pg:gcrt1.o%s} \
      %{!pg: \
	%{p:gcrt1.o%s} \
	%{!p:crt1.o%s}}} \
    crti.o%s %{!shared:crtbegin.o%s} %{shared:crtbeginS.o%s}}"

/* Provide an ENDFILE_SPEC appropriate for FreeBSD/i386.  Here we tack on our
   own magical crtend.o file (compare w/crtstuff.c) which provides part of the
   support for getting C++ file-scope static object constructed before
   entering `main', followed by the normal "finalizer" file, `crtn.o'.  */

#undef  ENDFILE_SPEC
#define ENDFILE_SPEC "\
  %{!maout: \
    %{!shared:crtend.o%s} \
    %{shared:crtendS.o%s} crtn.o%s}"


/************************[  Target stuff  ]***********************************/

/* Define the actual types of some ANSI-mandated types.
   Needs to agree with <machine/ansi.h>.  GCC defaults come from c-decl.c,
   c-common.c, and config/<arch>/<arch>.h.  */

#undef SIZE_TYPE
#define SIZE_TYPE	"unsigned int"

#undef PTRDIFF_TYPE
#define PTRDIFF_TYPE	"int"

/* This is the pseudo-op used to generate a 32-bit word of data with a
   specific value in some section.  */

#undef INT_ASM_OP
#define INT_ASM_OP	".long"

/* 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)

#undef  TARGET_VERSION
#define TARGET_VERSION	fprintf (stderr, " (i386 FreeBSD/ELF)");

#define MASK_PROFILER_EPILOGUE	010000000000
#define MASK_AOUT		004000000000	/* a.out not elf */
#define MASK_UNDERSCORES	002000000000	/* use leading _ */

#define TARGET_PROFILER_EPILOGUE	(target_flags & MASK_PROFILER_EPILOGUE)
#define TARGET_AOUT			(target_flags & MASK_AOUT)
#define TARGET_ELF			((target_flags & MASK_AOUT) == 0)
#define TARGET_UNDERSCORES		((target_flags & MASK_UNDERSCORES) != 0)

#undef	SUBTARGET_SWITCHES
#define SUBTARGET_SWITCHES						\
  { "profiler-epilogue",	 MASK_PROFILER_EPILOGUE, "Function profiler epilogue"}, \
  { "no-profiler-epilogue",	-MASK_PROFILER_EPILOGUE, "No function profiler epilogue"}, \
  { "aout",			 MASK_AOUT, "Generate an a.out (vs. ELF) binary"}, \
  { "no-aout",			-MASK_AOUT, "Do not generate an a.out binary"}, \
  { "underscores",		 MASK_UNDERSCORES, "Add leading underscores to symbols"}, \
  { "no-underscores",		-MASK_UNDERSCORES, "Do not add leading underscores to symbols"},

/* This goes away when the math emulator is fixed.  */
#undef  TARGET_DEFAULT
#define TARGET_DEFAULT \
  (MASK_80387 | MASK_IEEE_FP | MASK_FLOAT_RETURNS | MASK_NO_FANCY_MATH_387)

/* Prefix for internally generated assembler labels.  If we aren't using
   underscores, we are using prefix `.'s to identify labels that should
   be ignored, as in `i386/gas.h' --karl@cs.umb.edu  */
#undef  LPREFIX
#define LPREFIX ((TARGET_UNDERSCORES) ? "L" : ".L")

/* The a.out tools do not support "linkonce" sections. */
#undef  SUPPORTS_ONE_ONLY
#define SUPPORTS_ONE_ONLY	TARGET_ELF

/* Enable alias attribute support.  */
#undef  SET_ASM_OP
#define SET_ASM_OP		".set"

/* The a.out tools do not support "Lscope" .stabs symbols. */
#undef  NO_DBX_FUNCTION_END
#define NO_DBX_FUNCTION_END	TARGET_AOUT

/* In ELF, the function stabs come first, before the relative offsets.  */
#undef  DBX_FUNCTION_FIRST
#define DBX_CHECK_FUNCTION_FIRST TARGET_ELF

/* supply our own hook for calling __main() from main() */
#undef  INVOKE__main
#define INVOKE__main
#undef  GEN_CALL__MAIN
#define GEN_CALL__MAIN							\
  do {									\
    if (!(TARGET_ELF))							\
      emit_library_call (gen_rtx (SYMBOL_REF, Pmode, NAME__MAIN), 0,	\
			 VOIDmode, 0);					\
  } while (0)

/* Indicate that jump tables go in the text section.  This is
   necessary when compiling PIC code.  */
#undef  JUMP_TABLES_IN_TEXT_SECTION
#define JUMP_TABLES_IN_TEXT_SECTION	(flag_pic)

/* override the exception table positioning */
#undef  EXCEPTION_SECTION
#define EXCEPTION_SECTION() \
  do {									\
    if (TARGET_ELF)							\
      {									\
	named_section (NULL_TREE, ".gcc_except_table", 0);		\
      }									\
    else								\
      {									\
	if (flag_pic)							\
	  data_section ();						\
	else								\
	  readonly_data_section ();					\
      }									\
  } while (0);

/* Tell final.c that we don't need a label passed to mcount.  */
#undef  NO_PROFILE_COUNTERS
#define NO_PROFILE_COUNTERS

/* Output assembler code to FILE to begin profiling of the current function.
   LABELNO is an optional label.  */

#undef  FUNCTION_PROFILER
#define FUNCTION_PROFILER(FILE, LABELNO)  \
  do {									\
    char *_name = TARGET_AOUT ? "mcount" : ".mcount";			\
    if (flag_pic)							\
      fprintf ((FILE), "\tcall *%s@GOT(%%ebx)\n", _name);		\
    else								\
      fprintf ((FILE), "\tcall %s\n", _name);				\
  } while (0)

/* Output assembler code to FILE to end profiling of the current function.  */

#undef  FUNCTION_PROFILER_EPILOGUE
#define FUNCTION_PROFILER_EPILOGUE(FILE, DO_RTL)			\
  do {									\
    if (TARGET_PROFILER_EPILOGUE)					\
      {									\
	if (DO_RTL)							\
	  {								\
	  /* ".mexitcount" is specially handled in			\
	     ASM_HACK_SYMBOLREF () so that we don't need to handle	\
	     flag_pic or TARGET_AOUT here.  */				\
	    rtx xop;							\
	    xop = gen_rtx_MEM (FUNCTION_MODE,				\
			    gen_rtx_SYMBOL_REF (Pmode, ".mexitcount"));	\
	    emit_call_insn (gen_rtx (CALL, VOIDmode, xop, const0_rtx));	\
	  }								\
	else								\
	  {								\
	  /* XXX this !DO_RTL case is broken but not actually used.  */	\
	    char *_name = TARGET_AOUT ? "mcount" : ".mcount";		\
	    if (flag_pic)						\
	      fprintf (FILE, "\tcall *%s@GOT(%%ebx)\n", _name);		\
	    else							\
	      fprintf (FILE, "\tcall %s\n", _name);			\
	  }								\
      }									\
  } while (0)


/************************[  Assembler stuff  ]********************************/

/* Override the default comment-starter of "/" from unix.h.  */
#undef  ASM_COMMENT_START
#define ASM_COMMENT_START "#"

#undef  ASM_APP_ON
#define ASM_APP_ON	"#APP\n"

#undef  ASM_APP_OFF
#define ASM_APP_OFF	"#NO_APP\n"

/* This is how to begin an assembly language file.
   The .file command should always begin the output.
   ELF also needs a .version.  */

#undef  ASM_FILE_START
#define ASM_FILE_START(FILE)						\
  do {									\
    output_file_directive ((FILE), main_input_filename);		\
    if (TARGET_ELF)							\
      fprintf ((FILE), "\t.version\t\"01.01\"\n");			\
  } while (0)

/* This is how to store into the string BUF
   the symbol_ref name of an internal numbered label where
   PREFIX is the class of label and NUM is the number within the class.
   This is suitable for output with `assemble_name'.  */
#undef	ASM_GENERATE_INTERNAL_LABEL
#define ASM_GENERATE_INTERNAL_LABEL(BUF, PREFIX, NUMBER)		\
  sprintf ((BUF), "*%s%s%d", (TARGET_UNDERSCORES) ? "" : ".",		\
	   (PREFIX), (NUMBER))

/* This is how to output an internal numbered label where
   PREFIX is the class of label and NUM is the number within the class.
   For most svr4/ELF systems, the convention is that any symbol which begins
   with a period is not put into the linker symbol table by the assembler.  */
#undef	ASM_OUTPUT_INTERNAL_LABEL
#define	ASM_OUTPUT_INTERNAL_LABEL(FILE,PREFIX,NUM)			\
  fprintf ((FILE), "%s%s%d:\n", (TARGET_UNDERSCORES) ? "" : ".",	\
	   (PREFIX), (NUM))

/* This is how to output a reference to a user-level label named NAME.  */
#undef  ASM_OUTPUT_LABELREF
#define ASM_OUTPUT_LABELREF(FILE, NAME)					\
  do {									\
    char *_name = (NAME);						\
    /* Hack to avoid writing lots of rtl in				\
       FUNCTION_PROFILER_EPILOGUE ().  */				\
    if (*_name == '.' && strcmp(_name + 1, "mexitcount") == 0)		\
      {									\
	if (TARGET_AOUT)						\
	  _name++;							\
	if (flag_pic)							\
	  fprintf ((FILE), "*%s@GOT(%%ebx)", _name);			\
	else								\
	  fprintf ((FILE), "%s", _name);				\
      }									\
    else								\
      fprintf (FILE, "%s%s", TARGET_UNDERSCORES ? "_" : "", _name);	\
} while (0)

/* This is how to hack on the symbol code of certain relcalcitrant
   symbols to modify their output in output_pic_addr_const ().  */

#undef  ASM_HACK_SYMBOLREF_CODE
#define ASM_HACK_SYMBOLREF_CODE(NAME, CODE)				\
  do {									\
    /* Part of hack to avoid writing lots of rtl in			\
       FUNCTION_PROFILER_EPILOGUE ().  */				\
    char *_name = (NAME);						\
    if (*_name == '.' && strcmp(_name + 1, "mexitcount") == 0)		\
      (CODE) = 'X';							\
  } while (0)

/* This is how to output an element of a case-vector that is relative.
   This is only used for PIC code.  See comments by the `casesi' insn in
   i386.md for an explanation of the expression this outputs. */
#undef  ASM_OUTPUT_ADDR_DIFF_ELT
#define ASM_OUTPUT_ADDR_DIFF_ELT(FILE, BODY, VALUE, REL)		\
  fprintf ((FILE), "\t.long _GLOBAL_OFFSET_TABLE_+[.-%s%d]\n", LPREFIX, (VALUE))

#undef  ASM_OUTPUT_ALIGN
#define ASM_OUTPUT_ALIGN(FILE, LOG)      				\
  if ((LOG)!=0) {							\
    if (in_text_section())						\
      fprintf ((FILE), "\t.p2align %d,0x90\n", (LOG));			\
    else								\
      fprintf ((FILE), "\t.p2align %d\n", (LOG));			\
  }

#undef  ASM_OUTPUT_ALIGNED_COMMON
#define ASM_OUTPUT_ALIGNED_COMMON(FILE, NAME, SIZE, ALIGN)		\
  do {									\
    if (TARGET_ELF)							\
      {									\
	fprintf ((FILE), "%s", COMMON_ASM_OP);				\
	assemble_name ((FILE), (NAME));					\
	fprintf ((FILE), ",%u,%u\n", (SIZE), (ALIGN) / BITS_PER_UNIT);	\
      }									\
    else								\
      {									\
	int rounded = (SIZE);						\
	if (rounded == 0) rounded = 1;					\
	rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;		\
	rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)	\
		   * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));		\
	fprintf ((FILE), "%s ", COMMON_ASM_OP);				\
	assemble_name ((FILE), (NAME));					\
	fprintf ((FILE), ",%u\n", (rounded));				\
      }									\
  } while (0)

/* This says how to output assembler code to declare an
   uninitialized internal linkage data object.  Under SVR4,
   the linker seems to want the alignment of data objects
   to depend on their types.  We do exactly that here.  */

#undef  ASM_OUTPUT_ALIGNED_LOCAL
#define ASM_OUTPUT_ALIGNED_LOCAL(FILE, NAME, SIZE, ALIGN)		\
  do {									\
    if (TARGET_ELF)							\
      {									\
	fprintf ((FILE), "%s", LOCAL_ASM_OP);				\
	assemble_name ((FILE), (NAME));					\
	fprintf ((FILE), "\n");						\
	ASM_OUTPUT_ALIGNED_COMMON ((FILE), (NAME), (SIZE), (ALIGN));	\
      }									\
    else								\
      {									\
	int rounded = (SIZE);						\
	if (rounded == 0) rounded = 1;					\
	rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;		\
	rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)	\
		   * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));		\
	fputs ("\t.lcomm\t", (FILE));					\
	assemble_name ((FILE), (NAME));					\
	fprintf ((FILE), ",%u\n", (rounded));				\
      }									\
  } while (0)

/* How to output some space.  The rules are different depending on the
   object format.  */
#undef  ASM_OUTPUT_SKIP
#define ASM_OUTPUT_SKIP(FILE, SIZE) 					\
  do {									\
    if (TARGET_ELF)							\
      {									\
        fprintf ((FILE), "%s%u\n", SKIP_ASM_OP, (SIZE));		\
      }									\
    else								\
      {									\
        fprintf ((FILE), "\t.space\t%u\n", (SIZE));			\
      }									\
  } while (0)


#undef  ASM_OUTPUT_SOURCE_LINE
#define ASM_OUTPUT_SOURCE_LINE(FILE, LINE)				\
  do {									\
    static int sym_lineno = 1;						\
    if (TARGET_ELF)							\
      {									\
	fprintf ((FILE), ".stabn 68,0,%d,.LM%d-", (LINE), sym_lineno);	\
	assemble_name ((FILE), 						\
		XSTR (XEXP (DECL_RTL (current_function_decl), 0), 0));	\
	fprintf ((FILE), "\n.LM%d:\n", sym_lineno);			\
	sym_lineno += 1;						\
      }									\
    else								\
      {									\
	fprintf ((FILE), "\t%s %d,0,%d\n", ASM_STABD_OP, N_SLINE,	\
		lineno);						\
      }									\
  } while (0)

/* These macros generate the special .type and .size directives which
   are used to set the corresponding fields of the linker symbol table
   entries in an ELF object file under SVR4.  These macros also output
   the starting labels for the relevant functions/objects.  */

/* Write the extra assembler code needed to declare a function properly.
   Some svr4 assemblers need to also have something extra said about the
   function's return value.  We allow for that here.  */

#undef  ASM_DECLARE_FUNCTION_NAME
#define ASM_DECLARE_FUNCTION_NAME(FILE, NAME, DECL)			\
  do {									\
    fprintf (FILE, "\t%s\t ", TYPE_ASM_OP);				\
    assemble_name (FILE, NAME);						\
    putc (',', FILE);							\
    fprintf (FILE, TYPE_OPERAND_FMT, "function");			\
    putc ('\n', FILE);							\
    ASM_DECLARE_RESULT (FILE, DECL_RESULT (DECL));			\
    ASM_OUTPUT_LABEL(FILE, NAME);					\
  } while (0)

/* This is how to declare the size of a function.  */

#undef  ASM_DECLARE_FUNCTION_SIZE
#define ASM_DECLARE_FUNCTION_SIZE(FILE, FNAME, DECL)			\
  do {									\
    if (!flag_inhibit_size_directive)					\
      {									\
        char label[256];						\
	static int labelno;						\
	labelno++;							\
	ASM_GENERATE_INTERNAL_LABEL (label, "Lfe", labelno);		\
	ASM_OUTPUT_INTERNAL_LABEL (FILE, "Lfe", labelno);		\
	fprintf (FILE, "\t%s\t ", SIZE_ASM_OP);				\
	assemble_name (FILE, (FNAME));					\
        fprintf (FILE, ",");						\
	assemble_name (FILE, label);					\
        fprintf (FILE, "-");						\
	assemble_name (FILE, (FNAME));					\
	putc ('\n', FILE);						\
      }									\
  } while (0)


/* The routine used to output NUL terminated strings.  We use a special
   version of this for most svr4 targets because doing so makes the
   generated assembly code more compact (and thus faster to assemble)
   as well as more readable, especially for targets like the i386
   (where the only alternative is to output character sequences as
   comma separated lists of numbers).   */

#undef  ASM_OUTPUT_LIMITED_STRING
#define ASM_OUTPUT_LIMITED_STRING(FILE, STR)				\
  do {									\
      register unsigned char *_limited_str = (unsigned char *) (STR);	\
      register unsigned ch;						\
      fprintf ((FILE), "\t%s\t\"", STRING_ASM_OP);			\
      for (; (ch = *_limited_str); _limited_str++)			\
        {								\
	  register int escape;						\
	  switch (escape = ESCAPES[ch])					\
	    {								\
	    case 0:							\
	      putc (ch, (FILE));					\
	      break;							\
	    case 1:							\
	      fprintf ((FILE), "\\%03o", ch);				\
	      break;							\
	    default:							\
	      putc ('\\', (FILE));					\
	      putc (escape, (FILE));					\
	      break;							\
	    }								\
        }								\
      fprintf ((FILE), "\"\n");						\
  } while (0)

/* Switch into a generic section.

   We make the section read-only and executable for a function decl,
   read-only for a const data decl, and writable for a non-const data decl.

   If the section has already been defined, we must not
   emit the attributes here. The SVR4 assembler does not
   recognize section redefinitions.
   If DECL is NULL, no attributes are emitted.  */

#undef  ASM_OUTPUT_SECTION_NAME
#define ASM_OUTPUT_SECTION_NAME(FILE, DECL, NAME, RELOC)		\
  do {									\
    static struct section_info						\
      {									\
	struct section_info *next;				        \
	char *name;						        \
	enum sect_enum {SECT_RW, SECT_RO, SECT_EXEC} type;		\
      } *sections;							\
    struct section_info *s;						\
    char *mode;								\
    enum sect_enum type;						\
									\
    for (s = sections; s; s = s->next)					\
      if (!strcmp (NAME, s->name))					\
	break;								\
									\
    if (DECL && TREE_CODE (DECL) == FUNCTION_DECL)			\
      type = SECT_EXEC, mode = "ax";					\
    else if (DECL && DECL_READONLY_SECTION (DECL, RELOC))		\
      type = SECT_RO, mode = "a";					\
    else								\
      type = SECT_RW, mode = "aw";					\
									\
    if (s == 0)								\
      {									\
	s = (struct section_info *) xmalloc (sizeof (struct section_info));  \
	s->name = xmalloc ((strlen (NAME) + 1) * sizeof (*NAME));	\
	strcpy (s->name, NAME);						\
	s->type = type;							\
	s->next = sections;						\
	sections = s;							\
	fprintf (FILE, ".section\t%s,\"%s\",@progbits\n", NAME, mode);	\
      }									\
    else								\
      {									\
	if (DECL && s->type != type)					\
	  error_with_decl (DECL, "%s causes a section type conflict");	\
									\
	fprintf (FILE, ".section\t%s\n", NAME);				\
      }									\
  } while (0)

#undef  MAKE_DECL_ONE_ONLY
#define MAKE_DECL_ONE_ONLY(DECL)	(DECL_WEAK (DECL) = 1)
#undef  UNIQUE_SECTION_P
#define UNIQUE_SECTION_P(DECL)		(DECL_ONE_ONLY (DECL))
#undef  UNIQUE_SECTION
#define UNIQUE_SECTION(DECL,RELOC)					\
  do {									\
    int len;								\
    char *name, *string, *prefix;					\
									\
    name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (DECL));		\
									\
    if (! DECL_ONE_ONLY (DECL))						\
      {									\
	prefix = ".";                                             	\
	if (TREE_CODE (DECL) == FUNCTION_DECL)				\
	  prefix = ".text.";						\
	else if (DECL_READONLY_SECTION (DECL, RELOC))			\
	  prefix = ".rodata.";						\
	else								\
	  prefix = ".data.";						\
      }									\
    else if (TREE_CODE (DECL) == FUNCTION_DECL)				\
      prefix = ".gnu.linkonce.t.";					\
    else if (DECL_READONLY_SECTION (DECL, RELOC))			\
      prefix = ".gnu.linkonce.r.";					\
    else								\
      prefix = ".gnu.linkonce.d.";					\
									\
    len = strlen (name) + strlen (prefix);				\
    string = alloca (len + 1);						\
    sprintf (string, "%s%s", prefix, name);				\
									\
    DECL_SECTION_NAME (DECL) = build_string (len, string);		\
  } while (0)

/* A C statement or statements to switch to the appropriate
   section for output of DECL.  DECL is either a `VAR_DECL' node
   or a constant of some sort.  RELOC indicates whether forming
   the initial value of DECL requires link-time relocations.  */

#undef  SELECT_SECTION
#define SELECT_SECTION(DECL,RELOC)					\
  {									\
    if (flag_pic && RELOC)						\
      data_section ();							\
    else if (TREE_CODE (DECL) == STRING_CST)				\
      {									\
	if (! flag_writable_strings)					\
	  const_section ();						\
	else								\
	  data_section ();						\
      }									\
    else if (TREE_CODE (DECL) == VAR_DECL)				\
      {									\
	if (! DECL_READONLY_SECTION (DECL, RELOC))			\
	  data_section ();						\
	else								\
	  const_section ();						\
      }									\
    else								\
      const_section ();							\
  }

/* A C statement (sans semicolon) to output an element in the table of
   global constructors.  */
#undef  ASM_OUTPUT_CONSTRUCTOR
#define ASM_OUTPUT_CONSTRUCTOR(FILE, NAME)				\
  do {									\
    if (TARGET_ELF)							\
      {									\
	ctors_section ();						\
	fprintf ((FILE), "%s ", INT_ASM_OP);				\
	assemble_name ((FILE), (NAME));					\
	fprintf ((FILE), "\n");						\
      }									\
    else								\
      {									\
	fprintf (asm_out_file, "%s \"%s__CTOR_LIST__\",22,0,0,",	\
		 ASM_STABS_OP, (TARGET_UNDERSCORES) ? "_" : "");	\
	assemble_name (asm_out_file, name);				\
	fputc ('\n', asm_out_file);					\
      }									\
  } while (0)

/* A C statement (sans semicolon) to output an element in the table of
   global destructors.  */
#undef  ASM_OUTPUT_DESTRUCTOR
#define ASM_OUTPUT_DESTRUCTOR(FILE, NAME)				\
  do {									\
    if (TARGET_ELF)							\
      {									\
	dtors_section ();						\
	fprintf ((FILE), "%s ", INT_ASM_OP);				\
	assemble_name ((FILE), (NAME));					\
	fprintf ((FILE), "\n");						\
      }									\
    else								\
      {									\
	fprintf (asm_out_file, "%s \"%s__DTOR_LIST__\",22,0,0,",	\
		 ASM_STABS_OP, (TARGET_UNDERSCORES) ? "_" : "");	\
	assemble_name (asm_out_file, name);				\
	fputc ('\n', asm_out_file);					\
      }									\
  } while (0)

/* Define macro used to output shift-double opcodes when the shift
   count is in %cl.  Some assemblers require %cl as an argument;
   some don't.

   *OLD* GAS requires the %cl argument, so override i386/unix.h. */

#undef  AS3_SHIFT_DOUBLE
#define AS3_SHIFT_DOUBLE(a,b,c,d)	AS3 (a,b,c,d)


/************************[  Debugger stuff  ]*********************************/

/* Copy this from the svr4 specifications... */
/* Define the register numbers to be used in Dwarf debugging information.
   The SVR4 reference port C compiler uses the following register numbers
   in its Dwarf output code:
	0 for %eax (gnu regno = 0)
	1 for %ecx (gnu regno = 2)
	2 for %edx (gnu regno = 1)
	3 for %ebx (gnu regno = 3)
	4 for %esp (gnu regno = 7)
	5 for %ebp (gnu regno = 6)
	6 for %esi (gnu regno = 4)
	7 for %edi (gnu regno = 5)
   The following three DWARF register numbers are never generated by
   the SVR4 C compiler or by the GNU compilers, but SDB on x86/svr4
   believes these numbers have these meanings.
	8  for %eip    (no gnu equivalent)
	9  for %eflags (no gnu equivalent)
	10 for %trapno (no gnu equivalent)
   It is not at all clear how we should number the FP stack registers
   for the x86 architecture.  If the version of SDB on x86/svr4 were
   a bit less brain dead with respect to floating-point then we would
   have a precedent to follow with respect to DWARF register numbers
   for x86 FP registers, but the SDB on x86/svr4 is so completely
   broken with respect to FP registers that it is hardly worth thinking
   of it as something to strive for compatibility with.
   The version of x86/svr4 SDB I have at the moment does (partially)
   seem to believe that DWARF register number 11 is associated with
   the x86 register %st(0), but that's about all.  Higher DWARF
   register numbers don't seem to be associated with anything in
   particular, and even for DWARF regno 11, SDB only seems to under-
   stand that it should say that a variable lives in %st(0) (when
   asked via an `=' command) if we said it was in DWARF regno 11,
   but SDB still prints garbage when asked for the value of the
   variable in question (via a `/' command).
   (Also note that the labels SDB prints for various FP stack regs
   when doing an `x' command are all wrong.)
   Note that these problems generally don't affect the native SVR4
   C compiler because it doesn't allow the use of -O with -g and
   because when it is *not* optimizing, it allocates a memory
   location for each floating-point variable, and the memory
   location is what gets described in the DWARF AT_location
   attribute for the variable in question.
   Regardless of the severe mental illness of the x86/svr4 SDB, we
   do something sensible here and we use the following DWARF
   register numbers.  Note that these are all stack-top-relative
   numbers.
	11 for %st(0) (gnu regno = 8)
	12 for %st(1) (gnu regno = 9)
	13 for %st(2) (gnu regno = 10)
	14 for %st(3) (gnu regno = 11)
	15 for %st(4) (gnu regno = 12)
	16 for %st(5) (gnu regno = 13)
	17 for %st(6) (gnu regno = 14)
	18 for %st(7) (gnu regno = 15)
*/
#undef  DWARF_DBX_REGISTER_NUMBER
#define DWARF_DBX_REGISTER_NUMBER(n) \
((n) == 0 ? 0 \
 : (n) == 1 ? 2 \
 : (n) == 2 ? 1 \
 : (n) == 3 ? 3 \
 : (n) == 4 ? 6 \
 : (n) == 5 ? 7 \
 : (n) == 6 ? 5 \
 : (n) == 7 ? 4 \
 : ((n) >= FIRST_STACK_REG && (n) <= LAST_STACK_REG) ? (n)+3 \
 : (-1))

/* Now what stabs expects in the register.  */
#undef  STABS_DBX_REGISTER_NUMBER
#define STABS_DBX_REGISTER_NUMBER(n) \
((n) == 0 ? 0 : \
 (n) == 1 ? 2 : \
 (n) == 2 ? 1 : \
 (n) == 3 ? 3 : \
 (n) == 4 ? 6 : \
 (n) == 5 ? 7 : \
 (n) == 6 ? 4 : \
 (n) == 7 ? 5 : \
 (n) + 4)

#undef  DBX_REGISTER_NUMBER
#define DBX_REGISTER_NUMBER(n)	((write_symbols == DWARF2_DEBUG		\
	    			  || write_symbols == DWARF_DEBUG)	\
				? DWARF_DBX_REGISTER_NUMBER(n)		\
				: STABS_DBX_REGISTER_NUMBER(n))

/* tag end of file in elf mode */
#undef  DBX_OUTPUT_MAIN_SOURCE_FILE_END
#define DBX_OUTPUT_MAIN_SOURCE_FILE_END(FILE, FILENAME)			\
  do {									\
    if (TARGET_ELF) {							\
      fprintf ((FILE), "\t.text\n\t.stabs \"\",%d,0,0,.Letext\n.Letext:\n", \
		N_SO);							\
    }									\
  } while (0)

/* stabs-in-elf has offsets relative to function beginning */
#undef  DBX_OUTPUT_LBRAC
#define DBX_OUTPUT_LBRAC(FILE, NAME)					\
  do {									\
    fprintf (asmfile, "%s %d,0,0,", ASM_STABN_OP, N_LBRAC);		\
    assemble_name (asmfile, buf);					\
    if (TARGET_ELF)							\
      {									\
        fputc ('-', asmfile);						\
        assemble_name (asmfile,						\
	      	 XSTR (XEXP (DECL_RTL (current_function_decl), 0), 0));	\
      }									\
    fprintf (asmfile, "\n");						\
  } while (0)

#undef  DBX_OUTPUT_RBRAC
#define DBX_OUTPUT_RBRAC(FILE, NAME)					\
  do {									\
    fprintf (asmfile, "%s %d,0,0,", ASM_STABN_OP, N_RBRAC);		\
    assemble_name (asmfile, buf);					\
    if (TARGET_ELF)							\
      {									\
        fputc ('-', asmfile);						\
        assemble_name (asmfile,						\
		 XSTR (XEXP (DECL_RTL (current_function_decl), 0), 0));	\
      }									\
    fprintf (asmfile, "\n");						\
  } while (0)