svr4.h

早期freebsd实现

#undef ASM_OUTPUT_ALIGNED_LOCAL
#define ASM_OUTPUT_ALIGNED_LOCAL(FILE, NAME, SIZE, ALIGN)		\
do {									\
  fprintf ((FILE), "\t%s\t", LOCAL_ASM_OP);				\
  assemble_name ((FILE), (NAME));					\
  fprintf ((FILE), "\n");						\
  ASM_OUTPUT_ALIGNED_COMMON (FILE, NAME, SIZE, ALIGN);			\
} while (0)

/* This is the pseudo-op used to generate a 32-bit word of data with a
   specific value in some section.  This is the same for all known svr4
   assemblers.  */

#define INT_ASM_OP		".long"

/* This is the pseudo-op used to generate a contiguous sequence of byte
   values from a double-quoted string WITHOUT HAVING A TERMINATING NUL
   AUTOMATICALLY APPENDED.  This is the same for most svr4 assemblers.  */

#undef ASCII_DATA_ASM_OP
#define ASCII_DATA_ASM_OP	".ascii"

/* Support const sections and the ctors and dtors sections for g++.
   Note that there appears to be two different ways to support const
   sections at the moment.  You can either #define the symbol
   READONLY_DATA_SECTION (giving it some code which switches to the
   readonly data section) or else you can #define the symbols
   EXTRA_SECTIONS, EXTRA_SECTION_FUNCTIONS, SELECT_SECTION, and
   SELECT_RTX_SECTION.  We do both here just to be on the safe side.  */

#define USE_CONST_SECTION	1

#define CONST_SECTION_ASM_OP	".section\t.rodata"
#define CTORS_SECTION_ASM_OP	".section\t.ctors,\"a\",@progbits"
#define DTORS_SECTION_ASM_OP	".section\t.dtors,\"a\",@progbits"

/* On svr4, we *do* have support for the .init section, and we can put
   stuff in there to be executed before `main'.  We let crtstuff.c and
   other files know this by defining the following symbol.  The definition
   says how to change sections to the .init section.  This is the same
   for all know svr4 assemblers.  */

#define INIT_SECTION_ASM_OP	".section\t.init"

/* A default list of other sections which we might be "in" at any given
   time.  For targets that use additional sections (e.g. .tdesc) you
   should override this definition in the target-specific file which
   includes this file.  */

#undef EXTRA_SECTIONS
#define EXTRA_SECTIONS in_const, in_ctors, in_dtors

/* A default list of extra section function definitions.  For targets
   that use additional sections (e.g. .tdesc) you should override this
   definition in the target-specific file which includes this file.  */

#undef EXTRA_SECTION_FUNCTIONS
#define EXTRA_SECTION_FUNCTIONS						\
  CONST_SECTION_FUNCTION						\
  CTORS_SECTION_FUNCTION						\
  DTORS_SECTION_FUNCTION

#define READONLY_DATA_SECTION() const_section ()

extern void text_section();

#define CONST_SECTION_FUNCTION						\
void									\
const_section ()							\
{									\
  if (!USE_CONST_SECTION)						\
    text_section();							\
  else if (in_section != in_const)					\
    {									\
      fprintf (asm_out_file, "%s\n", CONST_SECTION_ASM_OP);		\
      in_section = in_const;						\
    }									\
}

#define CTORS_SECTION_FUNCTION						\
void									\
ctors_section ()							\
{									\
  if (in_section != in_ctors)						\
    {									\
      fprintf (asm_out_file, "%s\n", CTORS_SECTION_ASM_OP);		\
      in_section = in_ctors;						\
    }									\
}

#define DTORS_SECTION_FUNCTION						\
void									\
dtors_section ()							\
{									\
  if (in_section != in_dtors)						\
    {									\
      fprintf (asm_out_file, "%s\n", DTORS_SECTION_ASM_OP);		\
      in_section = in_dtors;						\
    }									\
}

/* A C statement (sans semicolon) to output an element in the table of
   global constructors.  */
#define ASM_OUTPUT_CONSTRUCTOR(FILE,NAME)				\
  do {									\
    ctors_section ();							\
    fprintf (FILE, "\t%s\t ", INT_ASM_OP);				\
    assemble_name (FILE, NAME);						\
    fprintf (FILE, "\n");						\
  } while (0)

/* A C statement (sans semicolon) to output an element in the table of
   global destructors.  */
#define ASM_OUTPUT_DESTRUCTOR(FILE,NAME)       				\
  do {									\
    dtors_section ();                   				\
    fprintf (FILE, "\t%s\t ", INT_ASM_OP);				\
    assemble_name (FILE, NAME);              				\
    fprintf (FILE, "\n");						\
  } 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.  */

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

/* A C statement or statements to switch to the appropriate
   section for output of RTX in mode MODE.  RTX is some kind
   of constant in RTL.  The argument MODE is redundant except
   in the case of a `const_int' rtx.  Currently, these always
   go into the const section.  */

#undef SELECT_RTX_SECTION
#define SELECT_RTX_SECTION(MODE,RTX) const_section()

/* Define the strings used for the special svr4 .type and .size directives.
   These strings generally do not vary from one system running svr4 to
   another, but if a given system (e.g. m88k running svr) needs to use
   different pseudo-op names for these, they may be overridden in the
   file which includes this one.  */

#define TYPE_ASM_OP	".type"
#define SIZE_ASM_OP	".size"
#define WEAK_ASM_OP	".weak"

/* The following macro defines the format used to output the second
   operand of the .type assembler directive.  Different svr4 assemblers
   expect various different forms for this operand.  The one given here
   is just a default.  You may need to override it in your machine-
   specific tm.h file (depending upon the particulars of your assembler).  */

#define TYPE_OPERAND_FMT	"@%s"

/* Write the extra assembler code needed to declare a function's result.
   Most svr4 assemblers don't require any special declaration of the
   result value, but there are exceptions.  */

#ifndef ASM_DECLARE_RESULT
#define ASM_DECLARE_RESULT(FILE, RESULT)
#endif

/* 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.  */

#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)

/* Write the extra assembler code needed to declare an object properly.  */

#define ASM_DECLARE_OBJECT_NAME(FILE, NAME, DECL)			\
  do {									\
    fprintf (FILE, "\t%s\t ", TYPE_ASM_OP);				\
    assemble_name (FILE, NAME);						\
    putc (',', FILE);							\
    fprintf (FILE, TYPE_OPERAND_FMT, "object");				\
    putc ('\n', FILE);							\
    if (!flag_inhibit_size_directive)					\
      {									\
	fprintf (FILE, "\t%s\t ", SIZE_ASM_OP);				\
	assemble_name (FILE, NAME);					\
	fprintf (FILE, ",%d\n",  int_size_in_bytes (TREE_TYPE (decl)));	\
      }									\
    ASM_OUTPUT_LABEL(FILE, NAME);					\
  } while (0)

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

#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)

/* A table of bytes codes used by the ASM_OUTPUT_ASCII and
   ASM_OUTPUT_LIMITED_STRING macros.  Each byte in the table
   corresponds to a particular byte value [0..255].  For any
   given byte value, if the value in the corresponding table
   position is zero, the given character can be output directly.
   If the table value is 1, the byte must be output as a \ooo
   octal escape.  If the tables value is anything else, then the
   byte value should be output as a \ followed by the value
   in the table.  Note that we can use standard UN*X escape
   sequences for many control characters, but we don't use
   \a to represent BEL because some svr4 assemblers (e.g. on
   the i386) don't know about that.   */

#define ESCAPES \
"\1\1\1\1\1\1\1\1btnvfr\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\
\0\0\"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\
\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\\\0\0\0\
\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\1\
\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\
\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\
\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\
\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1\1"

/* Some svr4 assemblers have a limit on the number of characters which
   can appear in the operand of a .string directive.  If your assembler
   has such a limitation, you should define STRING_LIMIT to reflect that
   limit.  Note that at least some svr4 assemblers have a limit on the
   actual number of bytes in the double-quoted string, and that they
   count each character in an escape sequence as one byte.  Thus, an
   escape sequence like \377 would count as four bytes.

   If your target assembler doesn't support the .string directive, you
   should define this to zero.
*/

#define STRING_LIMIT	((unsigned) 256)

#define STRING_ASM_OP	".string"

/* 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).   */

#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)

/* The routine used to output sequences of byte values.  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.  Note that if we find subparts of the
   character sequence which end with NUL (and which are shorter than
   STRING_LIMIT) we output those using ASM_OUTPUT_LIMITED_STRING.  */

#undef ASM_OUTPUT_ASCII
#define ASM_OUTPUT_ASCII(FILE, STR, LENGTH)				\
  do									\
    {									\
      register unsigned char *_ascii_bytes = (unsigned char *) (STR);	\
      register unsigned char *limit = _ascii_bytes + (LENGTH);		\
      register unsigned bytes_in_chunk = 0;				\
      for (; _ascii_bytes < limit; _ascii_bytes++)			\
        {								\
	  register unsigned char *p;					\
	  if (bytes_in_chunk >= 60)					\
	    {								\
	      fprintf ((FILE), "\"\n");					\
	      bytes_in_chunk = 0;					\
	    }								\
	  for (p = _ascii_bytes; p < limit && *p != '\0'; p++)		\
	    continue;							\
	  if (p < limit && (p - _ascii_bytes) <= STRING_LIMIT)		\
	    {								\
	      if (bytes_in_chunk > 0)					\
		{							\
		  fprintf ((FILE), "\"\n");				\
		  bytes_in_chunk = 0;					\
		}							\
	      ASM_OUTPUT_LIMITED_STRING ((FILE), _ascii_bytes);		\
	      _ascii_bytes = p;						\
	    }								\
	  else								\
	    {								\
	      register int escape;					\
	      register unsigned ch;					\
	      if (bytes_in_chunk == 0)					\
		fprintf ((FILE), "\t%s\t\"", ASCII_DATA_ASM_OP);	\
	      switch (escape = ESCAPES[ch = *_ascii_bytes])		\
		{							\
		case 0:							\
		  putc (ch, (FILE));					\
		  bytes_in_chunk++;					\
		  break;						\
		case 1:							\
		  fprintf ((FILE), "\\%03o", ch);			\
		  bytes_in_chunk += 4;					\
		  break;						\
		default:						\
		  putc ('\\', (FILE));					\
		  putc (escape, (FILE));				\
		  bytes_in_chunk += 2;					\
		  break;						\
		}							\
	    }								\
	}								\
      if (bytes_in_chunk > 0)						\
        fprintf ((FILE), "\"\n");					\
    }									\
  while (0)