gen.c

这个是LINUX下的GDB调度工具的源码

/* The IGEN simulator generator for GDB, the GNU Debugger.

   Copyright 2002 Free Software Foundation, Inc.

   Contributed by Andrew Cagney.

   This file is part of GDB.

   This program 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 of the License, or
   (at your option) any later version.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */


#include "misc.h"
#include "lf.h"
#include "table.h"
#include "filter.h"

#include "igen.h"
#include "ld-insn.h"
#include "ld-decode.h"
#include "gen.h"

static insn_uint
sub_val (insn_uint val, int val_last_pos, int first_pos, int last_pos)
{
  return ((val >> (val_last_pos - last_pos))
	  & (((insn_uint) 1 << (last_pos - first_pos + 1)) - 1));
}

static void
update_depth (lf *file, gen_entry *entry, int depth, void *data)
{
  int *max_depth = (int *) data;
  if (*max_depth < depth)
    *max_depth = depth;
}


int
gen_entry_depth (gen_entry *table)
{
  int depth = 0;
  gen_entry_traverse_tree (NULL, table, 1, NULL,	/*start */
			   update_depth, NULL,	/*end */
			   &depth);	/* data */
  return depth;
}


static void
print_gen_entry_path (line_ref *line, gen_entry *table, error_func *print)
{
  if (table->parent == NULL)
    {
      if (table->top->model != NULL)
	print (line, "%s", table->top->model->name);
      else
	print (line, "");
    }
  else
    {
      print_gen_entry_path (line, table->parent, print);
      print (NULL, ".%d", table->opcode_nr);
    }
}

static void
print_gen_entry_insns (gen_entry *table,
		       error_func *print,
		       char *first_message, char *next_message)
{
  insn_list *i;
  char *message;
  message = first_message;
  for (i = table->insns; i != NULL; i = i->next)
    {
      insn_entry *insn = i->insn;
      print_gen_entry_path (insn->line, table, print);
      print (NULL, ": %s.%s %s\n", insn->format_name, insn->name, message);
      if (next_message != NULL)
	message = next_message;
    }
}

/* same as strcmp */
static int
insn_field_cmp (insn_word_entry *l, insn_word_entry *r)
{
  while (1)
    {
      int bit_nr;
      if (l == NULL && r == NULL)
	return 0;		/* all previous fields the same */
      if (l == NULL)
	return -1;		/* left shorter than right */
      if (r == NULL)
	return +1;		/* left longer than right */
      for (bit_nr = 0; bit_nr < options.insn_bit_size; bit_nr++)
	{
	  if (l->bit[bit_nr]->field->type != insn_field_string)
	    continue;
	  if (r->bit[bit_nr]->field->type != insn_field_string)
	    continue;
	  if (l->bit[bit_nr]->field->conditions == NULL)
	    continue;
	  if (r->bit[bit_nr]->field->conditions == NULL)
	    continue;
	  if (0)
	    printf ("%s%s%s VS %s%s%s\n",
		    l->bit[bit_nr]->field->val_string,
		    l->bit[bit_nr]->field->conditions->test ==
		    insn_field_cond_eq ? "=" : "!",
		    l->bit[bit_nr]->field->conditions->string,
		    r->bit[bit_nr]->field->val_string,
		    r->bit[bit_nr]->field->conditions->test ==
		    insn_field_cond_eq ? "=" : "!",
		    r->bit[bit_nr]->field->conditions->string);
	  if (l->bit[bit_nr]->field->conditions->test == insn_field_cond_eq
	      && r->bit[bit_nr]->field->conditions->test ==
	      insn_field_cond_eq)
	    {
	      if (l->bit[bit_nr]->field->conditions->type ==
		  insn_field_cond_field
		  && r->bit[bit_nr]->field->conditions->type ==
		  insn_field_cond_field)
		/* somewhat arbitrary */
		{
		  int cmp = strcmp (l->bit[bit_nr]->field->conditions->string,
				    r->bit[bit_nr]->field->conditions->
				    string);
		  if (cmp != 0)
		    return cmp;
		  else
		    continue;
		}
	      if (l->bit[bit_nr]->field->conditions->type ==
		  insn_field_cond_field)
		return +1;
	      if (r->bit[bit_nr]->field->conditions->type ==
		  insn_field_cond_field)
		return -1;
	      /* The case of both fields having constant values should have
	         already have been handled because such fields are converted
	         into normal constant fields. */
	      continue;
	    }
	  if (l->bit[bit_nr]->field->conditions->test == insn_field_cond_eq)
	    return +1;		/* left = only */
	  if (r->bit[bit_nr]->field->conditions->test == insn_field_cond_eq)
	    return -1;		/* right = only */
	  /* FIXME: Need to some what arbitrarily order conditional lists */
	  continue;
	}
      l = l->next;
      r = r->next;
    }
}

/* same as strcmp */
static int
insn_word_cmp (insn_word_entry *l, insn_word_entry *r)
{
  while (1)
    {
      int bit_nr;
      if (l == NULL && r == NULL)
	return 0;		/* all previous fields the same */
      if (l == NULL)
	return -1;		/* left shorter than right */
      if (r == NULL)
	return +1;		/* left longer than right */
      for (bit_nr = 0; bit_nr < options.insn_bit_size; bit_nr++)
	{
	  if (l->bit[bit_nr]->mask < r->bit[bit_nr]->mask)
	    return -1;
	  if (l->bit[bit_nr]->mask > r->bit[bit_nr]->mask)
	    return 1;
	  if (l->bit[bit_nr]->value < r->bit[bit_nr]->value)
	    return -1;
	  if (l->bit[bit_nr]->value > r->bit[bit_nr]->value)
	    return 1;
	}
      l = l->next;
      r = r->next;
    }
}

/* same as strcmp */
static int
opcode_bit_cmp (opcode_bits *l, opcode_bits *r)
{
  if (l == NULL && r == NULL)
    return 0;			/* all previous bits the same */
  if (l == NULL)
    return -1;			/* left shorter than right */
  if (r == NULL)
    return +1;			/* left longer than right */
  /* most significant word */
  if (l->field->word_nr < r->field->word_nr)
    return +1;			/* left has more significant word */
  if (l->field->word_nr > r->field->word_nr)
    return -1;			/* right has more significant word */
  /* most significant bit? */
  if (l->first < r->first)
    return +1;			/* left as more significant bit */
  if (l->first > r->first)
    return -1;			/* right as more significant bit */
  /* nr bits? */
  if (l->last < r->last)
    return +1;			/* left as less bits */
  if (l->last > r->last)
    return -1;			/* right as less bits */
  /* value? */
  if (l->value < r->value)
    return -1;
  if (l->value > r->value)
    return 1;
  return 0;
}


/* same as strcmp */
static int
opcode_bits_cmp (opcode_bits *l, opcode_bits *r)
{
  while (1)
    {
      int cmp;
      if (l == NULL && r == NULL)
	return 0;		/* all previous bits the same */
      cmp = opcode_bit_cmp (l, r);
      if (cmp != 0)
	return cmp;
      l = l->next;
      r = r->next;
    }
}

/* same as strcmp */
static opcode_bits *
new_opcode_bits (opcode_bits *old_bits,
		 int value,
		 int first,
		 int last, insn_field_entry *field, opcode_field *opcode)
{
  opcode_bits *new_bits = ZALLOC (opcode_bits);
  new_bits->field = field;
  new_bits->value = value;
  new_bits->first = first;
  new_bits->last = last;
  new_bits->opcode = opcode;

  if (old_bits != NULL)
    {
      opcode_bits *new_list;
      opcode_bits **last = &new_list;
      new_list = new_opcode_bits (old_bits->next,
				  old_bits->value,
				  old_bits->first,
				  old_bits->last,
				  old_bits->field, old_bits->opcode);
      while (*last != NULL)
	{
	  int cmp = opcode_bit_cmp (new_bits, *last);
	  if (cmp < 0)		/* new < new_list */
	    {
	      break;
	    }
	  if (cmp == 0)
	    {
	      ERROR ("Duplicated insn bits in list");
	    }
	  last = &(*last)->next;
	}
      new_bits->next = *last;
      *last = new_bits;
      return new_list;
    }
  else
    {
      return new_bits;
    }
}

/* Same as strcmp().  */
static int
name_cmp (const char *l, const char *r)
{
  if (l == NULL && r == NULL)
    return 0;
  if (l != NULL && r == NULL)
    return -1;
  if (l == NULL && r != NULL)
    return +1;
  return strcmp (l, r);
}


typedef enum
{
  merge_duplicate_insns,
  report_duplicate_insns,
}
duplicate_insn_actions;

static insn_list *
insn_list_insert (insn_list **cur_insn_ptr,
		  int *nr_insns,
		  insn_entry * insn,
		  opcode_bits *expanded_bits,
		  opcode_field *opcodes,
		  int nr_prefetched_words,
		  duplicate_insn_actions duplicate_action)
{
  /* insert it according to the order of the fields & bits */
  for (; (*cur_insn_ptr) != NULL; cur_insn_ptr = &(*cur_insn_ptr)->next)
    {
      int cmp;

      /* key#1 sort according to the constant fields of each instruction */
      cmp = insn_word_cmp (insn->words, (*cur_insn_ptr)->insn->words);
      if (cmp < 0)
	break;
      else if (cmp > 0)
	continue;

      /* key#2 sort according to the expanded bits of each instruction */
      cmp = opcode_bits_cmp (expanded_bits, (*cur_insn_ptr)->expanded_bits);
      if (cmp < 0)
	break;
      else if (cmp > 0)
	continue;

      /* key#3 sort according to the non-constant fields of each instruction */
      cmp = insn_field_cmp (insn->words, (*cur_insn_ptr)->insn->words);
      if (cmp < 0)
	break;
      else if (cmp > 0)
	continue;

      if (duplicate_action == merge_duplicate_insns)
	{
	  /* key#4: If we're going to merge duplicates, also sort
	     according to the format_name.  Two instructions with
	     identical decode patterns, but different names, are
	     considered different when merging.  Duplicates are only
	     important when creating a decode table (implied by
	     report_duplicate_insns) as such a table only has the
	     instruction's bit code as a way of differentiating
	     between instructions.  */
	  int cmp = name_cmp (insn->format_name,
			      (*cur_insn_ptr)->insn->format_name);
	  if (cmp < 0)
	    break;
	  else if (cmp > 0)
	    continue;
	}

      if (duplicate_action == merge_duplicate_insns)
	{
	  /* key#5: If we're going to merge duplicates, also sort
	     according to the name.  See comment above for
	     format_name.  */
	  int cmp = name_cmp (insn->name, (*cur_insn_ptr)->insn->name);
	  if (cmp < 0)
	    break;
	  else if (cmp > 0)
	    continue;
	}

      /* duplicate keys, report problem */
      switch (duplicate_action)
	{
	case report_duplicate_insns:
	  /* It would appear that we have two instructions with the
	     same constant field values across all words and bits.
	     This error can also occure when insn_field_cmp() is
	     failing to differentiate between two instructions that
	     differ only in their conditional fields. */
	  warning (insn->line,
		   "Two instructions with identical constant fields\n");
	  error ((*cur_insn_ptr)->insn->line,
		 "Location of duplicate instruction\n");
	case merge_duplicate_insns:
	  /* Add the opcode path to the instructions list */
	  if (options.trace.insn_insertion)
	    {
	      notify ((*cur_insn_ptr)->insn->line,
		      "%s.%s: insert merge %s.%s\n",
		      (*cur_insn_ptr)->insn->format_name,
		      (*cur_insn_ptr)->insn->name,
		      insn->format_name,
		      insn->name);
	    }
	  if (opcodes != NULL)
	    {
	      insn_opcodes **last = &(*cur_insn_ptr)->opcodes;
	      while (*last != NULL)
		{
		  last = &(*last)->next;
		}
	      (*last) = ZALLOC (insn_opcodes);
	      (*last)->opcode = opcodes;
	    }
	  /* Use the larger nr_prefetched_words */
	  if ((*cur_insn_ptr)->nr_prefetched_words < nr_prefetched_words)
	    (*cur_insn_ptr)->nr_prefetched_words = nr_prefetched_words;
	  return (*cur_insn_ptr);
	}

    }

  /* create a new list entry and insert it */
  {
    insn_list *new_insn = ZALLOC (insn_list);
    if (options.trace.insn_insertion)
      {
	notify (insn->line,
		"%s.%s: insert new\n",
		insn->format_name,
		insn->name);
      }
    new_insn->insn = insn;
    new_insn->expanded_bits = expanded_bits;
    new_insn->next = (*cur_insn_ptr);
    new_insn->nr_prefetched_words = nr_prefetched_words;
    if (opcodes != NULL)
      {
	new_insn->opcodes = ZALLOC (insn_opcodes);
	new_insn->opcodes->opcode = opcodes;