ia64-gen.c

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      totbits += 16;
    }

  /* Now allocate the space.  */
  needed_bytes = (totbits + 7) / 8;
  if ((needed_bytes + insn_list_len) > tot_insn_list_len)
    {
      tot_insn_list_len += 256;
      insn_list = (unsigned char *) xrealloc (insn_list, tot_insn_list_len);
    }
  our_offset = insn_list_len;
  insn_list_len += needed_bytes;
  memset (insn_list + our_offset, 0, needed_bytes);

  /* Encode the skip entry by setting bit 6 set in the state op field,
     and store the # of bits to skip immediately after.  */
  if (ent->skip_flag)
    {
      bitsused += 5;
      insn_list[our_offset + 0] |= 0x40 | ((ent->bits_to_skip >> 2) & 0xf);
      insn_list[our_offset + 1] |= ((ent->bits_to_skip & 3) << 6);
    }

#define IS_ONLY_IFZERO(ENT) \
  ((ENT)->bits[0] != NULL && (ENT)->bits[1] == NULL && (ENT)->bits[2] == NULL \
   && (ENT)->disent == NULL && (ENT)->skip_flag == 0)

  /* Store an "if (bit is zero)" instruction by setting bit 7 in the
     state op field.  */
  if (ent->bits[0] != NULL)
    {
      struct bittree *nent = ent->bits[0];
      zero_count = 0;

      insn_list[our_offset] |= 0x80;

      /* We can encode sequences of multiple "if (bit is zero)" tests
	 by storing the # of zero bits to check in the lower 3 bits of
	 the instruction.  However, this only applies if the state
	 solely tests for a zero bit.  */

      if (IS_ONLY_IFZERO (ent))
	{
	  while (IS_ONLY_IFZERO (nent) && zero_count < 7)
	    {
	      nent = nent->bits[0];
	      zero_count++;
	    }

	  insn_list[our_offset + 0] |= zero_count;
	}
      zero_dest = insn_list_len;
      gen_dis_table (nent);
    }

  /* Now store the remaining tests.  We also handle a sole "termination
     entry" by storing it as an "any bit" test.  */

  for (x = 1; x < 3; x++)
    {
      if (ent->bits[x] != NULL || (x == 2 && ent->disent != NULL))
	{
	  struct bittree *i = ent->bits[x];
	  int idest;
	  int currbits = 15;

	  if (i != NULL)
	    {
	      /* If the instruction being branched to only consists of
		 a termination entry, use the termination entry as the
		 place to branch to instead.  */
	      if (i->bits[0] == NULL && i->bits[1] == NULL
		  && i->bits[2] == NULL && i->disent != NULL)
		{
		  idest = i->disent->ournum;
		  i = NULL;
		}
	      else
		idest = insn_list_len - our_offset;
	    }
	  else
	    idest = ent->disent->ournum;

	  /* If the destination offset for the if (bit is 1) test is less 
	     than 256 bytes away, we can store it as 8-bits instead of 16;
	     the instruction has bit 5 set for the 16-bit address, and bit
	     4 for the 8-bit address.  Since we've already allocated 16
	     bits for the address we need to deallocate the space.

	     Note that branchings within the table are relative, and
	     there are no branches that branch past our instruction yet
	     so we do not need to adjust any other offsets.  */
	  if (x == 1)
	    {
	      if (idest <= 256)
		{
		  int start = our_offset + bitsused / 8 + 1;

		  memmove (insn_list + start,
			   insn_list + start + 1,
			   insn_list_len - (start + 1));
		  currbits = 7;
		  totbits -= 8;
		  needed_bytes--;
		  insn_list_len--;
		  insn_list[our_offset] |= 0x10;
		  idest--;
		}
	      else
		insn_list[our_offset] |= 0x20;
	    }
	  else
	    {
	      /* An instruction which solely consists of a termination
		 marker and whose disassembly name index is < 4096
		 can be stored in 16 bits.  The encoding is slightly
		 odd; the upper 4 bits of the instruction are 0x3, and
		 bit 3 loses its normal meaning.  */

	      if (ent->bits[0] == NULL && ent->bits[1] == NULL
		  && ent->bits[2] == NULL && ent->skip_flag == 0
		  && ent->disent != NULL
		  && ent->disent->ournum < (32768 + 4096))
		{
		  int start = our_offset + bitsused / 8 + 1;

		  memmove (insn_list + start,
			   insn_list + start + 1,
			   insn_list_len - (start + 1));
		  currbits = 11;
		  totbits -= 5;
		  bitsused--;
		  needed_bytes--;
		  insn_list_len--;
		  insn_list[our_offset] |= 0x30;
		  idest &= ~32768;
		}
	      else
		insn_list[our_offset] |= 0x08;
	    }

	  if (debug)
	    {
	      int id = idest;

	      if (i == NULL)
		id |= 32768;
	      else if (! (id & 32768))
		id += our_offset;

	      if (x == 1)
		printf ("%d: if (1) goto %d\n", our_offset, id);
	      else
		printf ("%d: try %d\n", our_offset, id);
	    }

	  /* Store the address of the entry being branched to.  */
	  while (currbits >= 0)
	    {
	      unsigned char *byte = insn_list + our_offset + bitsused / 8;

	      if (idest & (1 << currbits))
		*byte |= (1 << (7 - (bitsused % 8)));

	      bitsused++;
	      currbits--;
	    }

	  /* Now generate the states for the entry being branched to.  */
	  if (i != NULL)
	    gen_dis_table (i);
	}
    }

  if (debug)
    {
      if (ent->skip_flag)
	printf ("%d: skipping %d\n", our_offset, ent->bits_to_skip);
  
      if (ent->bits[0] != NULL)
	printf ("%d: if (0:%d) goto %d\n", our_offset, zero_count + 1,
		zero_dest);
    }

  if (bitsused != totbits)
    abort ();
}

static void
print_dis_table (void)
{
  int x;
  struct disent *cent = disinsntable;

  printf ("static const char dis_table[] = {\n");
  for (x = 0; x < insn_list_len; x++)
    {
      if ((x > 0) && ((x % 12) == 0))
	printf ("\n");

      printf ("0x%02x, ", insn_list[x]);
    }
  printf ("\n};\n\n");

  printf ("static const struct ia64_dis_names ia64_dis_names[] = {\n");
  while (cent != NULL)
    {
      struct disent *ent = cent;

      while (ent != NULL)
	{
	  printf ("{ 0x%x, %d, %d, %d },\n", ent->completer_index,
		  ent->insn, (ent->nexte != NULL ? 1 : 0),
                  ent->priority);
	  ent = ent->nexte;
	}
      cent = cent->next_ent;
    }
  printf ("};\n\n");
}

static void
generate_disassembler (void)
{
  int i;

  bittree = make_bittree_entry ();

  for (i = 0; i < otlen; i++)
    {
      struct main_entry *ptr = ordered_table[i];

      if (ptr->opcode->type != IA64_TYPE_DYN)
	add_dis_entry (bittree,
		       ptr->opcode->opcode, ptr->opcode->mask, 
		       ptr->main_index,
		       ptr->completers, 1);
    }

  compact_distree (bittree);
  finish_distable ();
  gen_dis_table (bittree);

  print_dis_table ();
}

static void
print_string_table (void)
{
  int x;
  char lbuf[80], buf[80];
  int blen = 0;

  printf ("static const char * const ia64_strings[] = {\n");
  lbuf[0] = '\0';

  for (x = 0; x < strtablen; x++)
    {
      int len;
      
      if (strlen (string_table[x]->s) > 75)
	abort ();

      sprintf (buf, " \"%s\",", string_table[x]->s);
      len = strlen (buf);

      if ((blen + len) > 75)
	{
	  printf (" %s\n", lbuf);
	  lbuf[0] = '\0';
	  blen = 0;
	}
      strcat (lbuf, buf);
      blen += len;
    }

  if (blen > 0)
    printf (" %s\n", lbuf);

  printf ("};\n\n");
}

static struct completer_entry **glist;
static int glistlen = 0;
static int glisttotlen = 0;

/* If the completer trees ENT1 and ENT2 are equal, return 1.  */

static int
completer_entries_eq (ent1, ent2)
     struct completer_entry *ent1, *ent2;
{
  while (ent1 != NULL && ent2 != NULL)
    {
      if (ent1->name->num != ent2->name->num
	  || ent1->bits != ent2->bits
	  || ent1->mask != ent2->mask
	  || ent1->is_terminal != ent2->is_terminal
          || ent1->dependencies != ent2->dependencies
          || ent1->order != ent2->order)
	return 0;

      if (! completer_entries_eq (ent1->addl_entries, ent2->addl_entries))
	return 0;

      ent1 = ent1->alternative;
      ent2 = ent2->alternative;
    }

  return ent1 == ent2;
}

/* Insert ENT into the global list of completers and return it.  If an
   equivalent entry (according to completer_entries_eq) already exists,
   it is returned instead.  */
static struct completer_entry *
insert_gclist (struct completer_entry *ent)
{
  if (ent != NULL)
    {
      int i;
      int x;
      int start = 0, end;

      ent->addl_entries = insert_gclist (ent->addl_entries);
      ent->alternative = insert_gclist (ent->alternative);

      i = glistlen / 2;
      end = glistlen;

      if (glisttotlen == glistlen)
	{
	  glisttotlen += 20;
	  glist = (struct completer_entry **)
	    xrealloc (glist, sizeof (struct completer_entry *) * glisttotlen);
	}

      if (glistlen == 0)
	{
	  glist[0] = ent;
	  glistlen = 1;
	  return ent;
	}

      if (ent->name->num < glist[0]->name->num)
	i = 0;
      else if (ent->name->num > glist[end - 1]->name->num)
	i = end;
      else
	{
	  int c;

	  while (1)
	    {
	      i = (start + end) / 2;
	      c = ent->name->num - glist[i]->name->num;

	      if (c < 0)
		end = i - 1;
	      else if (c == 0)
		{
		  while (i > 0 
			 && ent->name->num == glist[i - 1]->name->num)
		    i--;

		  break;
		}
	      else
		start = i + 1;

	      if (start > end)
		break;
	    }

	  if (c == 0)
	    {
	      while (i < glistlen)
		{
		  if (ent->name->num != glist[i]->name->num)
		    break;

		  if (completer_entries_eq (ent, glist[i]))
		    return glist[i];

		  i++;
		}
	    }
	}

      for (; i > 0 && i < glistlen; i--)
	if (ent->name->num >= glist[i - 1]->name->num)
	  break;

      for (; i < glistlen; i++)
	if (ent->name->num < glist[i]->name->num)
	  break;

      for (x = glistlen - 1; x >= i; x--)
	glist[x + 1] = glist[x];

      glist[i] = ent;
      glistlen++;
    }
  return ent;
}

static int
get_prefix_len (name)
     const char *name;
{
  char *c;

  if (name[0] == '\0')
    return 0;

  c = strchr (name, '.');
  if (c != NULL)
    return c - name;
  else
    return strlen (name);
}

static void
compute_completer_bits (ment, ent)
     struct main_entry *ment;
     struct completer_entry *ent;
{
  while (ent != NULL)
    {
      compute_completer_bits (ment, ent->addl_entries);

      if (ent->is_terminal)
	{
	  ia64_insn mask = 0;
	  ia64_insn our_bits = ent->bits;
	  struct completer_entry *p = ent->parent;
	  ia64_insn p_bits;
	  int x;

	  while (p != NULL && ! p->is_terminal)
	    p = p->parent;
      
	  if (p != NULL)
	    p_bits = p->bits;
	  else
	    p_bits = ment->opcode->opcode;

	  for (x = 0; x < 64; x++)
	    {
	      ia64_insn m = ((ia64_insn) 1) << x;

	      if ((p_bits & m) != (our_bits & m))
		mask |= m;
	      else
		our_bits &= ~m;
	    }
	  ent->bits = our_bits;
	  ent->mask = mask;
	}
      else
	{
	  ent->bits = 0;
	  ent->mask = 0;
	}

      ent = ent->alternative;
    }
}

/* Find identical completer trees that are used in different
   instructions and collapse their entries.  */
static void
collapse_redundant_completers (void)
{
  struct main_entry *ptr;
  int x;

  for (ptr = maintable; ptr != NULL; ptr = ptr->next)
    {
      if (ptr->completers == NULL)
	abort ()