gen.c

这个是LINUX下的GDB调度工具的源码

    }

  /* did we find anything */
  if (opcode_rule == NULL)
    {
      /* the decode table failed, this set of instructions haven't
         been uniquely identified */
      if (table->nr_insns > 1)
	{
	  print_gen_entry_insns (table, warning,
				 "was not uniquely decoded",
				 "decodes to the same entry");
	  error (NULL, "");
	}
      return;
    }

  /* Determine the number of words that must have been prefetched for
     this table to function */
  if (table->parent == NULL)
    table->nr_prefetched_words = table->opcode_rule->word_nr + 1;
  else if (table->opcode_rule->word_nr + 1 >
	   table->parent->nr_prefetched_words)
    table->nr_prefetched_words = table->opcode_rule->word_nr + 1;
  else
    table->nr_prefetched_words = table->parent->nr_prefetched_words;

  /* back link what we found to its parent */
  if (table->parent != NULL)
    {
      ASSERT (table->parent->opcode != NULL);
      table->opcode->parent = table->parent->opcode;
    }

  /* report the rule being used to expand the instructions */
  if (options.trace.rule_selection)
    {
      print_gen_entry_path (table->opcode_rule->line, table, notify);
      notify (NULL,
	      ": decode - word %d, bits [%d..%d] in [%d..%d], opcodes %d, entries %d\n",
	      table->opcode->word_nr,
	      i2target (options.hi_bit_nr, table->opcode->first),
	      i2target (options.hi_bit_nr, table->opcode->last),
	      i2target (options.hi_bit_nr, table->opcode_rule->first),
	      i2target (options.hi_bit_nr, table->opcode_rule->last),
	      table->opcode->nr_opcodes, table->nr_entries);
    }

  /* expand the raw instructions according to the opcode */
  {
    insn_list *entry;
    for (entry = table->insns; entry != NULL; entry = entry->next)
      {
	if (options.trace.insn_expansion)
	  {
	    print_gen_entry_path (table->opcode_rule->line, table, notify);
	    notify (NULL, ": expand - %s.%s\n",
		    entry->insn->format_name, entry->insn->name);
	  }
	gen_entry_insert_expanding (table, entry->insn);
      }
  }

  /* dump the results */
  if (options.trace.entries)
    {
      gen_entry *entry;
      for (entry = table->entries; entry != NULL; entry = entry->sibling)
	{
	  insn_list *l;
	  print_gen_entry_path (table->opcode_rule->line, entry, notify);
	  notify (NULL, ": %d - entries %d -",
		  entry->opcode_nr, entry->nr_insns);
	  for (l = entry->insns; l != NULL; l = l->next)
	    notify (NULL, " %s.%s", l->insn->format_name, l->insn->name);
	  notify (NULL, "\n");
	}
    }

  /* perform a combine pass if needed */
  if (table->opcode_rule->with_combine)
    {
      gen_entry *entry;
      for (entry = table->entries; entry != NULL; entry = entry->sibling)
	{
	  if (entry->combined_parent == NULL)
	    {
	      gen_entry **last = &entry->combined_next;
	      gen_entry *alt;
	      for (alt = entry->sibling; alt != NULL; alt = alt->sibling)
		{
		  if (alt->combined_parent == NULL
		      && insn_list_cmp (entry->insns, alt->insns) == 0)
		    {
		      alt->combined_parent = entry;
		      *last = alt;
		      last = &alt->combined_next;
		    }
		}
	    }
	}
      if (options.trace.combine)
	{
	  int nr_unique = 0;
	  gen_entry *entry;
	  for (entry = table->entries; entry != NULL; entry = entry->sibling)
	    {
	      if (entry->combined_parent == NULL)
		{
		  insn_list *l;
		  gen_entry *duplicate;
		  nr_unique++;
		  print_gen_entry_path (table->opcode_rule->line, entry,
					notify);
		  for (duplicate = entry->combined_next; duplicate != NULL;
		       duplicate = duplicate->combined_next)
		    {
		      notify (NULL, "+%d", duplicate->opcode_nr);
		    }
		  notify (NULL, ": entries %d -", entry->nr_insns);
		  for (l = entry->insns; l != NULL; l = l->next)
		    {
		      notify (NULL, " %s.%s",
			      l->insn->format_name, l->insn->name);
		    }
		  notify (NULL, "\n");
		}
	    }
	  print_gen_entry_path (table->opcode_rule->line, table, notify);
	  notify (NULL,
		  ": combine - word %d, bits [%d..%d] in [%d..%d], opcodes %d, entries %d, unique %d\n",
		  table->opcode->word_nr, i2target (options.hi_bit_nr,
						    table->opcode->first),
		  i2target (options.hi_bit_nr, table->opcode->last),
		  i2target (options.hi_bit_nr, table->opcode_rule->first),
		  i2target (options.hi_bit_nr, table->opcode_rule->last),
		  table->opcode->nr_opcodes, table->nr_entries, nr_unique);
	}
    }

  /* Check that the rule did more than re-arange the order of the
     instructions */
  {
    gen_entry *entry;
    for (entry = table->entries; entry != NULL; entry = entry->sibling)
      {
	if (entry->combined_parent == NULL)
	  {
	    if (insn_list_cmp (table->insns, entry->insns) == 0)
	      {
		print_gen_entry_path (table->opcode_rule->line, table,
				      warning);
		warning (NULL,
			 ": Applying rule just copied all instructions\n");
		print_gen_entry_insns (entry, warning, "Copied", NULL);
		error (NULL, "");
	      }
	  }
      }
  }

  /* if some form of expanded table, fill in the missing dots */
  switch (table->opcode_rule->gen)
    {
    case padded_switch_gen:
    case array_gen:
    case goto_switch_gen:
      if (!table->opcode->is_boolean)
	{
	  gen_entry **entry = &table->entries;
	  gen_entry *illegals = NULL;
	  gen_entry **last_illegal = &illegals;
	  int opcode_nr = 0;
	  while (opcode_nr < table->opcode->nr_opcodes)
	    {
	      if ((*entry) == NULL || (*entry)->opcode_nr != opcode_nr)
		{
		  /* missing - insert it under our feet at *entry */
		  gen_entry_insert_insn (table, table->top->isa->illegal_insn, table->opcode->word_nr, 0,	/* nr_prefetched_words == 0 for invalid */
					 opcode_nr, NULL);
		  ASSERT ((*entry) != NULL);
		  ASSERT ((*entry)->opcode_nr == opcode_nr);
		  (*last_illegal) = *entry;
		  (*last_illegal)->combined_parent = illegals;
		  last_illegal = &(*last_illegal)->combined_next;
		}
	      entry = &(*entry)->sibling;
	      opcode_nr++;
	    }
	  /* oops, will have pointed the first illegal insn back to
	     its self.  Fix this */
	  if (illegals != NULL)
	    illegals->combined_parent = NULL;
	}
      break;
    case switch_gen:
    case invalid_gen:
      /* ignore */
      break;
    }

  /* and do the same for the newly created sub entries but *only*
     expand entries that haven't been combined. */
  {
    gen_entry *entry;
    for (entry = table->entries; entry != NULL; entry = entry->sibling)
      {
	if (entry->combined_parent == NULL)
	  {
	    gen_entry_expand_insns (entry);
	  }
      }
  }
}

void
gen_tables_expand_insns (gen_table *gen)
{
  gen_list *entry;
  for (entry = gen->tables; entry != NULL; entry = entry->next)
    {
      gen_entry_expand_insns (entry->table);
    }
}


/* create a list of all the semantic functions that need to be
   generated.  Eliminate any duplicates. Verify that the decode stage
   worked. */

static void
make_gen_semantics_list (lf *file, gen_entry *entry, int depth, void *data)
{
  gen_table *gen = (gen_table *) data;
  insn_list *insn;
  /* Not interested in an entrie that have been combined into some
     other entry at the same level */
  if (entry->combined_parent != NULL)
    return;

  /* a leaf should contain exactly one instruction. If not the decode
     stage failed. */
  ASSERT (entry->nr_insns == 1);

  /* Enter this instruction into the list of semantic functions. */
  insn = insn_list_insert (&gen->semantics, &gen->nr_semantics,
			   entry->insns->insn,
			   entry->expanded_bits,
			   entry->parent->opcode,
			   entry->insns->nr_prefetched_words,
			   merge_duplicate_insns);
  /* point the table entry at the real semantic function */
  ASSERT (insn != NULL);
  entry->insns->semantic = insn;
}


void
gen_tables_expand_semantics (gen_table *gen)
{
  gen_list *entry;
  for (entry = gen->tables; entry != NULL; entry = entry->next)
    {
      gen_entry_traverse_tree (NULL, entry->table, 1,	/* depth */
			       NULL,	/* start-handler */
			       make_gen_semantics_list,	/* leaf-handler */
			       NULL,	/* end-handler */
			       gen);	/* data */
    }
}



#ifdef MAIN


static void
dump_opcode_field (lf *file,
		   char *prefix,
		   opcode_field *field, char *suffix, int levels)
{
  lf_printf (file, "%s(opcode_field *) 0x%lx", prefix, (long) field);
  if (levels && field != NULL)
    {
      lf_indent (file, +1);
      lf_printf (file, "\n(first %d)", field->first);
      lf_printf (file, "\n(last %d)", field->last);
      lf_printf (file, "\n(nr_opcodes %d)", field->nr_opcodes);
      lf_printf (file, "\n(is_boolean %d)", field->is_boolean);
      lf_printf (file, "\n(boolean_constant %d)", field->boolean_constant);
      dump_opcode_field (file, "\n(parent ", field->parent, ")", levels - 1);
      lf_indent (file, -1);
    }
  lf_printf (file, "%s", suffix);
}


static void
dump_opcode_bits (lf *file,
		  char *prefix, opcode_bits *bits, char *suffix, int levels)
{
  lf_printf (file, "%s(opcode_bits *) 0x%lx", prefix, (long) bits);

  if (levels && bits != NULL)
    {
      lf_indent (file, +1);
      lf_printf (file, "\n(value %d)", bits->value);
      dump_opcode_field (file, "\n(opcode ", bits->opcode, ")", 0);
      dump_insn_field (file, "\n(field ", bits->field, ")");
      dump_opcode_bits (file, "\n(next ", bits->next, ")", levels - 1);
      lf_indent (file, -1);
    }
  lf_printf (file, "%s", suffix);
}



static void
dump_insn_list (lf *file, char *prefix, insn_list *entry, char *suffix)
{
  lf_printf (file, "%s(insn_list *) 0x%lx", prefix, (long) entry);

  if (entry != NULL)
    {
      lf_indent (file, +1);
      dump_insn_entry (file, "\n(insn ", entry->insn, ")");
      lf_printf (file, "\n(next 0x%lx)", (long) entry->next);
      lf_indent (file, -1);
    }
  lf_printf (file, "%s", suffix);
}


static void
dump_insn_word_entry_list_entries (lf *file,
				   char *prefix,
				   insn_list *entry, char *suffix)
{
  lf_printf (file, "%s", prefix);
  while (entry != NULL)
    {
      dump_insn_list (file, "\n(", entry, ")");
      entry = entry->next;
    }
  lf_printf (file, "%s", suffix);
}


static void
dump_gen_entry (lf *file,
		char *prefix, gen_entry *table, char *suffix, int levels)
{

  lf_printf (file, "%s(gen_entry *) 0x%lx", prefix, (long) table);

  if (levels && table !=NULL)
    {

      lf_indent (file, +1);
      lf_printf (file, "\n(opcode_nr %d)", table->opcode_nr);
      lf_printf (file, "\n(word_nr %d)", table->word_nr);
      dump_opcode_bits (file, "\n(expanded_bits ", table->expanded_bits, ")",
			-1);
      lf_printf (file, "\n(nr_insns %d)", table->nr_insns);
      dump_insn_word_entry_list_entries (file, "\n(insns ", table->insns,
					 ")");
      dump_decode_rule (file, "\n(opcode_rule ", table->opcode_rule, ")");
      dump_opcode_field (file, "\n(opcode ", table->opcode, ")", 0);
      lf_printf (file, "\n(nr_entries %d)", table->nr_entries);
      dump_gen_entry (file, "\n(entries ", table->entries, ")",
		      table->nr_entries);
      dump_gen_entry (file, "\n(sibling ", table->sibling, ")", levels - 1);
      dump_gen_entry (file, "\n(parent ", table->parent, ")", 0);
      lf_indent (file, -1);
    }
  lf_printf (file, "%s", suffix);
}

static void
dump_gen_list (lf *file,
	       char *prefix, gen_list *entry, char *suffix, int levels)
{
  while (entry != NULL)
    {
      lf_printf (file, "%s(gen_list *) 0x%lx", prefix, (long) entry);
      dump_gen_entry (file, "\n(", entry->table, ")", levels);
      lf_printf (file, "\n(next (gen_list *) 0x%lx)", (long) entry->next);
      lf_printf (file, "%s", suffix);
    }
}


static void
dump_gen_table (lf *file,
		char *prefix, gen_table *gen, char *suffix, int levels)
{
  lf_printf (file, "%s(gen_table *) 0x%lx", prefix, (long) gen);
  lf_printf (file, "\n(isa (insn_table *) 0x%lx)", (long) gen->isa);
  lf_printf (file, "\n(rules (decode_table *) 0x%lx)", (long) gen->rules);
  dump_gen_list (file, "\n(", gen->tables, ")", levels);
  lf_printf (file, "%s", suffix);
}


igen_options options;

int
main (int argc, char **argv)
{
  decode_table *decode_rules;
  insn_table *instructions;
  gen_table *gen;
  lf *l;

  if (argc != 7)
    error (NULL,
	   "Usage: insn <filter-in> <hi-bit-nr> <insn-bit-size> <widths> <decode-table> <insn-table>\n");

  INIT_OPTIONS (options);

  filter_parse (&options.flags_filter, argv[1]);

  options.hi_bit_nr = a2i (argv[2]);
  options.insn_bit_size = a2i (argv[3]);
  options.insn_specifying_widths = a2i (argv[4]);
  ASSERT (options.hi_bit_nr < options.insn_bit_size);

  instructions = load_insn_table (argv[6], NULL);
  decode_rules = load_decode_table (argv[5]);
  gen = make_gen_tables (instructions, decode_rules);

  gen_tables_expand_insns (gen);

  l = lf_open ("-", "stdout", lf_omit_references, lf_is_text, "tmp-ld-insn");

  dump_gen_table (l, "(", gen, ")\n", -1);
  return 0;
}

#endif