tc-i370.c

基于4个mips核的noc设计

     0x5C, 0x00, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
 /*E8   Y     Z                                     */
     0x59, 0x5A, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
 /*F0   0     1     2     3     4     5     6     7 */
     0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
 /*F8   8     9                                     */
     0x38, 0x39, 0x00, 0x00, 0x00, 0x00, 0x00, 0xFF
};

/* ebcdic translation tables needed for 3270 support */
static void
i370_ebcdic (unused)
     int unused;
{
  char *p, *end;
  char delim = 0;
  size_t nbytes;

  nbytes = strlen (input_line_pointer);
  end = input_line_pointer + nbytes;
  while ('\r' == *end) end --;
  while ('\n' == *end) end --;

  delim = *input_line_pointer;
  if (('\'' == delim) || ('\"' == delim)) {
    input_line_pointer ++;
    end = rindex (input_line_pointer, delim);
  }

  if (end > input_line_pointer)
    {
      nbytes = end - input_line_pointer +1;
      p = frag_more (nbytes);
      while (end > input_line_pointer)
	{
	  *p = ascebc [(unsigned char) (*input_line_pointer)];
	  ++p; ++input_line_pointer;
	}
      *p = '\0';
    }
  if (delim == *input_line_pointer) ++input_line_pointer;
}


/* stub out a couple of routines */
static void
i370_rmode (unused)
     int unused;
{
  as_tsktsk ("rmode ignored");
}

static void
i370_dsect (sect)
     int sect;
{
  char *save_line = input_line_pointer;
  static char section[] = ".data\n";

  /* Just pretend this is .section .data */
  input_line_pointer = section;
  obj_elf_section (sect);

  input_line_pointer = save_line;
}

static void
i370_csect (unused)
     int unused;
{
  as_tsktsk ("csect not supported");
}


/* DC Define Const  is only partially supported.
 * For samplecode on what to do, look at i370_elf_cons() above.
 * This code handles pseudoops of the style
 * DC   D'3.141592653'   # in sysv4, .double 3.14159265
 * DC   F'1'             # in sysv4, .long   1
 */
static void
i370_dc(unused)
     int unused;
{
  char * p, tmp[50];
  int nbytes=0;
  expressionS exp;
  char type=0;

  if (is_it_end_of_statement ())
    {
      demand_empty_rest_of_line ();
      return;
    }

  /* figure out the size */
  type = *input_line_pointer++;
  switch (type)
    {
    case 'H':  /* 16-bit */
      nbytes = 2;
      break;
    case 'E':  /* 32-bit */
    case 'F':  /* 32-bit */
      nbytes = 4;
      break;
    case 'D':  /* 64-bit */
      nbytes = 8;
      break;
    default:
      as_bad ("unsupported DC type");
      return;
    }

  /* get rid of pesky quotes */
  if ('\'' == *input_line_pointer)
    {
      char * close;
      ++input_line_pointer;
      close = strchr (input_line_pointer, '\'');
      if (close)
	*close= ' ';
      else
	as_bad ("missing end-quote");
    }
  if ('\"' == *input_line_pointer)
    {
      char * close;
      ++input_line_pointer;
      close = strchr (input_line_pointer, '\"');
      if (close)
	*close= ' ';
      else
	as_bad ("missing end-quote");
    }

  switch (type)
    {
    case 'H':  /* 16-bit */
    case 'F':  /* 32-bit */
      expression (&exp);
      emit_expr (&exp, nbytes);
      break;
    case 'E':  /* 32-bit */
    case 'D':  /* 64-bit */
      md_atof (type, tmp, &nbytes);
      p = frag_more (nbytes);
      memcpy (p, tmp, nbytes);
      break;
    default:
      as_bad ("unsupported DC type");
      return;
    }

  demand_empty_rest_of_line ();
}


/* provide minimal support for DS Define Storage */
static void
i370_ds (unused)
     int unused;
{
  /* DS 0H or DS 0F or DS 0D */
  if ('0' == *input_line_pointer)
    {
      int alignment = 0;  /* left shift 1<<align */
      input_line_pointer ++;
      switch (*input_line_pointer++)
	{
	case 'H':  /* 16-bit */
	  alignment = 1;
	  break;
	case 'F':  /* 32-bit */
	  alignment = 2;
	  break;
	case 'D':  /* 64-bit */
	  alignment = 3;
	  break;
	default:
	  as_bad ("unsupported alignment");
	  return;
	}
      frag_align (alignment, 0, 0);
      record_alignment (now_seg, alignment);
    }
  else
    {
      as_bad ("this DS form not yet supported");
    }
}

/* Solaris pseudo op to change to the .rodata section.  */
static void
i370_elf_rdata (sect)
     int sect;
{
  char *save_line = input_line_pointer;
  static char section[] = ".rodata\n";

  /* Just pretend this is .section .rodata */
  input_line_pointer = section;
  obj_elf_section (sect);

  input_line_pointer = save_line;
}

/* Pseudo op to make file scope bss items */
static void
i370_elf_lcomm(unused)
     int unused;
{
  register char *name;
  register char c;
  register char *p;
  offsetT size;
  register symbolS *symbolP;
  offsetT align;
  segT old_sec;
  int old_subsec;
  char *pfrag;
  int align2;

  name = input_line_pointer;
  c = get_symbol_end ();

  /* just after name is now '\0' */
  p = input_line_pointer;
  *p = c;
  SKIP_WHITESPACE ();
  if (*input_line_pointer != ',')
    {
      as_bad ("Expected comma after symbol-name: rest of line ignored.");
      ignore_rest_of_line ();
      return;
    }

  input_line_pointer++;        	/* skip ',' */
  if ((size = get_absolute_expression ()) < 0)
    {
      as_warn (".COMMon length (%ld.) <0! Ignored.", (long) size);
      ignore_rest_of_line ();
      return;
    }

  /* The third argument to .lcomm is the alignment.  */
  if (*input_line_pointer != ',')
    align = 8;
  else
    {
      ++input_line_pointer;
      align = get_absolute_expression ();
      if (align <= 0)
        {
          as_warn ("ignoring bad alignment");
          align = 8;
        }
    }

  *p = 0;
  symbolP = symbol_find_or_make (name);
  *p = c;

  if (S_IS_DEFINED (symbolP) && ! S_IS_COMMON (symbolP))
    {
      as_bad ("Ignoring attempt to re-define symbol `%s'.",
              S_GET_NAME (symbolP));
      ignore_rest_of_line ();
      return;
    }

  if (S_GET_VALUE (symbolP) && S_GET_VALUE (symbolP) != (valueT) size)
    {
      as_bad ("Length of .lcomm \"%s\" is already %ld. Not changed to %ld.",
              S_GET_NAME (symbolP),
              (long) S_GET_VALUE (symbolP),
              (long) size);

      ignore_rest_of_line ();
      return;
    }

  /* allocate_bss: */
  old_sec = now_seg;
  old_subsec = now_subseg;
  if (align)
    {
      /* convert to a power of 2 alignment */
      for (align2 = 0; (align & 1) == 0; align >>= 1, ++align2)
	;
      if (align != 1)
        {
          as_bad ("Common alignment not a power of 2");
          ignore_rest_of_line ();
          return;
        }
    }
  else
    align2 = 0;

  record_alignment (bss_section, align2);
  subseg_set (bss_section, 0);
  if (align2)
    frag_align (align2, 0, 0);
  if (S_GET_SEGMENT (symbolP) == bss_section)
    symbol_get_frag (symbolP)->fr_symbol = 0;
  symbol_set_frag (symbolP, frag_now);
  pfrag = frag_var (rs_org, 1, 1, (relax_substateT) 0, symbolP, size,
        	    (char *) 0);
  *pfrag = 0;
  S_SET_SIZE (symbolP, size);
  S_SET_SEGMENT (symbolP, bss_section);
  subseg_set (old_sec, old_subsec);
  demand_empty_rest_of_line ();
}

/* Validate any relocations emitted for -mrelocatable, possibly adding
   fixups for word relocations in writable segments, so we can adjust
   them at runtime.  */
static void
i370_elf_validate_fix (fixp, seg)
     fixS *fixp;
     segT seg;
{
  if (fixp->fx_done || fixp->fx_pcrel)
    return;

  switch (shlib)
    {
    case SHLIB_NONE:
    case SHLIB_PIC:
      return;

    case SHILB_MRELOCATABLE:
      if (fixp->fx_r_type <= BFD_RELOC_UNUSED
          && fixp->fx_r_type != BFD_RELOC_16_GOTOFF
          && fixp->fx_r_type != BFD_RELOC_HI16_GOTOFF
          && fixp->fx_r_type != BFD_RELOC_LO16_GOTOFF
          && fixp->fx_r_type != BFD_RELOC_HI16_S_GOTOFF
          && fixp->fx_r_type != BFD_RELOC_32_BASEREL
          && fixp->fx_r_type != BFD_RELOC_LO16_BASEREL
          && fixp->fx_r_type != BFD_RELOC_HI16_BASEREL
          && fixp->fx_r_type != BFD_RELOC_HI16_S_BASEREL
          && strcmp (segment_name (seg), ".got2") != 0
          && strcmp (segment_name (seg), ".dtors") != 0
          && strcmp (segment_name (seg), ".ctors") != 0
          && strcmp (segment_name (seg), ".fixup") != 0
          && strcmp (segment_name (seg), ".stab") != 0
          && strcmp (segment_name (seg), ".gcc_except_table") != 0
          && strcmp (segment_name (seg), ".ex_shared") != 0)
        {
          if ((seg->flags & (SEC_READONLY | SEC_CODE)) != 0
              || fixp->fx_r_type != BFD_RELOC_CTOR)
            {
              as_bad_where (fixp->fx_file, fixp->fx_line,
        		    "Relocation cannot be done when using -mrelocatable");
            }
        }
      return;
    }
}
#endif /* OBJ_ELF */


#define LITERAL_POOL_SUPPORT
#ifdef LITERAL_POOL_SUPPORT
/* Provide support for literal pools within the text section.  */
/* Loosely based on similar code from tc-arm.c  */
/*
 * We will use four symbols to locate four parts of the literal pool.
 *    These four sections contain 64,32,16 and 8-bit constants; we use
 *    four sections so that all memory access can be appropriately aligned.
 *    That is, we want to avoid mixing these together so that we don't
 *    waste space padding out to alignments.  The four pointers
 *    longlong_poolP, word_poolP, etc. point to a symbol labeling the
 *    start of each pool part.
 *
 * lit_pool_num increments from zero to infinity and uniquely id's
 *    -- its used to generate the *_poolP symbol name.
 */

#define MAX_LITERAL_POOL_SIZE 1024

typedef struct literalS
{
  struct expressionS  exp;
  char * sym_name;
  char size;  /* 1,2,4 or 8 */
  short offset;
} literalT;

literalT literals[MAX_LITERAL_POOL_SIZE];
int next_literal_pool_place = 0; /* Next free entry in the pool */

static symbolS *longlong_poolP = NULL;   /* 64-bit pool entries */
static symbolS *word_poolP = NULL;       /* 32-bit pool entries */
static symbolS *short_poolP = NULL;      /* 16-bit pool entries */
static symbolS *byte_poolP = NULL;       /* 8-bit  pool entries */

static int lit_pool_num = 1;

/* create a new, empty symbol */
static symbolS *
symbol_make_empty (void)
{
  return symbol_create (FAKE_LABEL_NAME, undefined_section,
  			(valueT) 0, &zero_address_frag);
}

/* add an expression to the literal pool */
static  void
add_to_lit_pool (expressionS *exx, char *name, int sz)
{
  int lit_count = 0;
  int offset_in_pool = 0;

  /* start a new pool, if necessary */
  if (8 == sz && NULL == longlong_poolP)
    longlong_poolP = symbol_make_empty();
  else if (4 == sz && NULL == word_poolP)
    word_poolP = symbol_make_empty();
  else if (2 == sz && NULL == short_poolP)
    short_poolP = symbol_make_empty();
  else if (1 == sz && NULL == byte_poolP)
    byte_poolP = symbol_make_empty();

  /* Check if this literal value is already in the pool: */
  /* hack alert -- we should probably be checking expressions
   * of type O_symbol as well ...  */
  /* hack alert XXX this is probably(certainly?) broken for O_big,
   * which includes 64-bit long-longs ...
   */
  while (lit_count < next_literal_pool_place)
    {
      if (exx->X_op == O_constant
          && literals[lit_count].exp.X_op == exx->X_op
          && literals[lit_count].exp.X_add_number == exx->X_add_number
          && literals[lit_count].exp.X_unsigned == exx->X_unsigned
          && literals[lit_count].size == sz)
        break;
      else if (literals[lit_count].sym_name
	       && name
	       && !strcmp (name, literals[lit_count].sym_name))
        break;
      if (sz == literals[lit_count].size)
	offset_in_pool += sz;
      lit_count ++;
    }

  if (lit_count == next_literal_pool_place) /* new entry */
    {
      if (next_literal_pool_place > MAX_LITERAL_POOL_SIZE)
        {
          as_bad("Literal Pool Overflow");
        }