gencode.c

gdb-6.0 linux 下的调试工具

expand_opcode (shift, val, i, s)
     int shift;
     int val;
     int i;
     char *s;
{
  int j;

  if (*s == 0)
    {
      table[val] = i;
    }
  else
    {
      switch (s[0])
	{

	case '0':
	case '1':
	  {
	    int m, mv;

	    val |= bton (s) << shift;
	    if (s[2] == '0' || s[2] == '1')
	      expand_opcode (shift - 4, val, i, s + 4);
	    else if (s[2] == 'N')
	      for (j = 0; j < 4; j++)
		expand_opcode (shift - 4, val | (j << shift), i, s + 4);
	    else if (s[2] == 'x')
	      for (j = 0; j < 4; j += 2)
		for (m = 0; m < 32; m++)
		  {
		    /* Ignore illegal nopy */
		    if ((m & 7) == 0 && m != 0)
		      continue;
		    mv = m & 3 | (m & 4) << 2 | (m & 8) << 3 | (m & 16) << 4;
		    expand_opcode (shift - 4, val | mv | (j << shift), i,
				   s + 4);
		  }
	    else if (s[2] == 'y')
	      for (j = 0; j < 2; j++)
		expand_opcode (shift - 4, val | (j << shift), i, s + 4);
	    break;
	  }
	case 'n':
	case 'm':
	  for (j = 0; j < 16; j++)
	    {
	      expand_opcode (shift - 4, val | (j << shift), i, s + 4);

	    }
	  break;
	case 'M':
	  /* A1, A0,X0,X1,Y0,Y1,M0,A1G,M1,M1G */
	  for (j = 5; j < 16; j++)
	    if (j != 6)
	      expand_opcode (shift - 4, val | (j << shift), i, s + 4);
	  break;
	case 'G':
	  /* A1G, A0G: */
	  for (j = 13; j <= 15; j +=2)
	    expand_opcode (shift - 4, val | (j << shift), i, s + 4);
	  break;
	case 's':
	  /* System registers mach, macl, pr: */
	  for (j = 0; j < 3; j++)
	    expand_opcode (shift - 4, val | (j << shift), i, s + 4);
	  /* System registers fpul, fpscr/dsr, a0, x0, x1, y0, y1: */
	  for (j = 5; j < 12; j++)
	    expand_opcode (shift - 4, val | (j << shift), i, s + 4);
	  break;
	case 'X':
	case 'a':
	  val |= bton (s) << shift;
	  for (j = 0; j < 16; j += 8)
	    expand_opcode (shift - 4, val | (j << shift), i, s + 4);
	  break;
	case 'Y':
	case 'A':
	  val |= bton (s) << shift;
	  for (j = 0; j < 8; j += 4)
	    expand_opcode (shift - 4, val | (j << shift), i, s + 4);
	  break;

	default:
	  for (j = 0; j < (1 << (shift + 4)); j++)
	    {
	      table[val | j] = i;
	    }
	}
    }
}

/* Print the jump table used to index an opcode into a switch
   statement entry. */

static void
dumptable (name, size, start)
     char *name;
     int size;
     int start;
{
  int lump = 256;
  int online = 16;

  int i = start;

  printf ("unsigned char %s[%d]={\n", name, size);
  while (i < start + size)
    {
      int j = 0;

      printf ("/* 0x%x */\n", i);

      while (j < lump)
	{
	  int k = 0;
	  while (k < online)
	    {
	      printf ("%2d", table[i + j + k]);
	      if (j + k < lump)
		printf (",");

	      k++;
	    }
	  j += k;
	  printf ("\n");
	}
      i += j;
    }
  printf ("};\n");
}


static void
filltable (p)
     op *p;
{
  static int index = 1;

  sorttab ();
  for (; p->name; p++)
    {
      p->index = index++;
      expand_opcode (12, 0, p->index, p->code);
    }
}

/* Table already contais all the switch case tags for 16-bit opcode double
   data transfer (ddt) insns, and the switch case tag for processing parallel
   processing insns (ppi) for code 0xf800 (ppi nopx nopy).  Copy the
   latter tag to represent all combinations of ppi with ddt.  */
static void
ppi_moves ()
{
  int i;

  for (i = 0xf000; i < 0xf400; i++)
    if (table[i])
      table[i + 0x800] = table[0xf800];
}

static void
gensim_caselist (p)
     op *p;
{
  for (; p->name; p++)
    {
      int j;
      int sextbit = -1;
      int needm = 0;
      int needn = 0;
      
      char *s = p->code;

      printf ("  /* %s %s */\n", p->name, p->code);
      printf ("  case %d:      \n", p->index);

      printf ("    {\n");
      while (*s)
	{
	  switch (*s)
	    {
	    case '0':
	    case '1':
	      s += 2;
	      break;
	    case '.':
	      s += 4;
	      break;
	    case 'n':
	      printf ("      int n = (iword >>8) & 0xf;\n");
	      needn = 1;
	      s += 4;
	      break;
	    case 'N':
	      printf ("      int n = (((iword >> 8) - 2) & 0x3) + 2;\n");
	      s += 2;
	      break;
	    case 'x':
	      printf ("      int n = ((iword >> 9) & 1) + 4;\n");
	      needn = 1;
	      s += 2;
	      break;
	    case 'y':
	      printf ("      int n = ((iword >> 8) & 1) + 4;\n");
	      needn = 1;
	      s += 2;
	      break;
	    case 'm':
	      needm = 1;
	    case 's':
	    case 'M':
	    case 'G':
	      printf ("      int m = (iword >>4) & 0xf;\n");
	      s += 4;
	      break;
	    case 'X':
	      printf ("      int m = ((iword >> 7) & 1) + 8;\n");
	      s += 2;
	      break;
	    case 'a':
	      printf ("      int m = 7 - ((iword >> 6) & 2);\n");
	      s += 2;
	      break;
	    case 'Y':
	      printf ("      int m = ((iword >> 6) & 1) + 10;\n");
	      s += 2;
	      break;
	    case 'A':
	      printf ("      int m = 7 - ((iword >> 5) & 2);\n");
	      s += 2;
	      break;

	    case 'i':
	      printf ("      int i = (iword & 0x");

	      switch (s[1])
		{
		case '4':
		  printf ("f");
		  break;
		case '8':
		  printf ("ff");
		  break;
		case '1':
		  sextbit = 12;

		  printf ("fff");
		  break;
		}
	      printf (")");

	      switch (s[3])
		{
		case '1':
		  break;
		case '2':
		  printf ("<<1");
		  break;
		case '4':
		  printf ("<<2");
		  break;
		}
	      printf (";\n");
	      s += 4;
	    }
	}
      if (sextbit > 0)
	{
	  printf ("      i = (i ^ (1<<%d))-(1<<%d);\n",
		  sextbit - 1, sextbit - 1);
	}

      if (needm && needn)
	printf ("      TB(m,n);\n");  
      else if (needm)
	printf ("      TL(m);\n");
      else if (needn)
	printf ("      TL(n);\n");

      {
	/* Do the refs */
	char *r;
	for (r = p->refs; *r; r++)
	  {
	    if (*r == '0') printf("      CREF(0);\n"); 
	    if (*r == '8') printf("      CREF(8);\n"); 
	    if (*r == '9') printf("      CREF(9);\n"); 
	    if (*r == 'n') printf("      CREF(n);\n"); 
	    if (*r == 'm') printf("      CREF(m);\n"); 
	  }
      }

      printf ("      {\n");
      for (j = 0; j < MAX_NR_STUFF; j++)
	{
	  if (p->stuff[j])
	    {
	      printf ("        %s\n", p->stuff[j]);
	    }
	}
      printf ("      }\n");

      {
	/* Do the defs */
	char *r;
	for (r = p->defs; *r; r++) 
	  {
	    if (*r == '0') printf("      CDEF(0);\n"); 
	    if (*r == 'n') printf("      CDEF(n);\n"); 
	    if (*r == 'm') printf("      CDEF(m);\n"); 
	  }
      }

      printf ("      break;\n");
      printf ("    }\n");
    }
}

static void
gensim ()
{
  printf ("{\n");
  printf ("  switch (jump_table[iword]) {\n");

  gensim_caselist (tab);
  gensim_caselist (movsxy_tab);

  printf ("  default:\n");
  printf ("    {\n");
  printf ("      RAISE_EXCEPTION (SIGILL);\n");
  printf ("    }\n");
  printf ("  }\n");
  printf ("}\n");
}

static void
gendefines ()
{
  op *p;
  filltable (tab);
  for (p = tab; p->name; p++)
    {
      char *s = p->name;
      printf ("#define OPC_");
      while (*s) {
	if (isupper(*s)) 
	  *s = tolower(*s);
	if (isalpha(*s)) printf("%c", *s);
	if (*s == ' ') printf("_");
	if (*s == '@') printf("ind_");
	if (*s == ',') printf("_");
	s++;
      }
      printf(" %d\n",p->index);
    }
}

static int ppi_index;

/* Take an ppi code, expand all varying fields in it and fill all the
   right entries in 'table' with the opcode index.  */

static void
expand_ppi_code (val, i, s)
     int val;
     int i;
     char *s;
{
  int j;

  for (;;)
    {
      switch (s[0])
	{
	/* The last eight bits are disregarded for the switch table.  */
	case 'm':
	case 'x':
	case '.':
	  table[val] = i;
	  return;
	case '0':
	  val += val;
	  s++;
	  break;
	case '1':
	  val += val + 1;
	  s++;
	  break;
	case 'i':
	case 'e': case 'f':
	  val += val;
	  s++;
	  expand_ppi_code (val, i, s);
	  val++;
	  break;
	case 'c':
	  val <<= 2;
	  s += 2;
	  val++;
	  expand_ppi_code (val, ppi_index++, s);
	  val++;
	  expand_ppi_code (val, i, s);
	  val++;
	  break;
	}
    }
}

static void
ppi_filltable ()
{
  op *p;
  ppi_index = 1;

  for (p = ppi_tab; p->name; p++)
    {
      p->index = ppi_index++;
      expand_ppi_code (0, p->index, p->code);
    }
}

static void
ppi_gensim ()
{
  op *p = ppi_tab;

  printf ("#define DSR_MASK_G 0x80\n");
  printf ("#define DSR_MASK_Z 0x40\n");
  printf ("#define DSR_MASK_N 0x20\n");
  printf ("#define DSR_MASK_V 0x10\n");
  printf ("\n");
  printf ("#define COMPUTE_OVERFLOW do {\\\n");
  printf ("  overflow = res_grd != SIGN32 (res) ? DSR_MASK_V : 0; \\\n");
  printf ("  if (overflow && S) \\\n");
  printf ("    { \\\n");
  printf ("      if (res_grd & 0x80) \\\n");
  printf ("        { \\\n");
  printf ("          res = 0x80000000; \\\n");
  printf ("          res_grd |=  0xff; \\\n");
  printf ("        } \\\n");
  printf ("      else \\\n");
  printf ("        { \\\n");
  printf ("          res = 0x7fffffff; \\\n");
  printf ("          res_grd &= ~0xff; \\\n");
  printf ("        } \\\n");
  printf ("      overflow = 0; \\\n");
  printf ("    } \\\n");
  printf ("} while (0)\n");
  printf ("\n");
  printf ("#define ADD_SUB_GE \\\n");
  printf ("  (greater_equal = ~(overflow << 3 & res_grd) & DSR_MASK_G)\n");
  printf ("\n");
  printf ("static void\n");
  printf ("ppi_insn (iword)\n");
  printf ("     int iword;\n");
  printf ("{\n");
  printf ("  static char e_tab[] = { 8,  9, 10,  5};\n");
  printf ("  static char f_tab[] = {10, 11,  8,  5};\n");
  printf ("  static char x_tab[] = { 8,  9,  7,  5};\n");
  printf ("  static char y_tab[] = {10, 11, 12, 14};\n");
  printf ("  static char g_tab[] = {12, 14,  7,  5};\n");
  printf ("  static char u_tab[] = { 8, 10,  7,  5};\n");
  printf ("\n");
  printf ("  int z;\n");
  printf ("  int res, res_grd;\n");
  printf ("  int carry, overflow, greater_equal;\n");
  printf ("\n");
  printf ("  switch (ppi_table[iword >> 8]) {\n");

  for (; p->name; p++)
    {
      int shift, j;
      int cond = 0;
      int havedecl = 0;
      
      char *s = p->code;

      printf ("  /* %s %s */\n", p->name, p->code);
      printf ("  case %d:      \n", p->index);

      printf ("    {\n");
      for (shift = 16; *s; )
	{
	  switch (*s)
	    {
	    case 'i':
	      printf ("      int i = (iword >> 4) & 0x7f;\n");
	      s += 6;
	      break;
	    case 'e':
	    case 'f':
	    case 'x':
	    case 'y':
	    case 'g':
	    case 'u':
	      shift -= 2;
	      printf ("      int %c = %c_tab[(iword >> %d) & 3];\n",
		      *s, *s, shift);
	      havedecl = 1;
	      s += 2;
	      break;
	    case 'c':
	      printf ("      if ((((iword >> 8) ^ DSR) & 1) == 0)\n");
	      printf ("\tbreak;\n");
	      printf ("    }\n");
	      printf ("  case %d:      \n", p->index + 1);
	      printf ("    {\n");
	      cond = 1;
	    case '0':
	    case '1':
	    case '.':
	      shift -= 2;
	      s += 2;
	      break;
	    case 'z':
	      if (havedecl)
		printf ("\n");
	      printf ("      z = iword & 0xf;\n");
	      havedecl = 2;
	      s += 4;
	      break;
	    }
	}
      if (havedecl == 1)
	printf ("\n");
      else if (havedecl == 2)
	printf ("      {\n");
      for (j = 0; j < MAX_NR_STUFF; j++)
	{
	  if (p->stuff[j])
	    {
	      printf ("      %s%s\n",
		      (havedecl == 2 ? "  " : ""),
		      p->stuff[j]);
	    }
	}
      if (havedecl == 2)
	printf ("      }\n");
      if (cond)
	{
	  printf ("      if (iword & 0x200)\n");
	  printf ("        goto assign_z;\n");
	}
      printf ("      break;\n");
      printf ("    }\n");
    }

  printf ("  default:\n");
  printf ("    {\n");
  printf ("      RAISE_EXCEPTION (SIGILL);\n");
  printf ("      return;\n");
  printf ("    }\n");
  printf ("  }\n");
  printf ("  DSR &= ~0xf1;\n");
  printf ("  if (res || res_grd)\n");
  printf ("    DSR |= greater_equal | res_grd >> 2 & DSR_MASK_N | overflow;\n");
  printf ("  else\n");
  printf ("    DSR |= DSR_MASK_Z | overflow;\n");
  printf (" assign_dc:\n");
  printf ("  switch (DSR >> 1 & 7)\n");
  printf ("    {\n");
  printf ("    case 0: /* Carry Mode */\n");
  printf ("      DSR |= carry;\n");
  printf ("    case 1: /* Negative Value Mode */\n");
  printf ("      DSR |= res_grd >> 7 & 1;\n");
  printf ("    case 2: /* Zero Value Mode */\n");
  printf ("      DSR |= DSR >> 6 & 1;\n");
  printf ("    case 3: /* Overflow mode\n");
  printf ("      DSR |= overflow >> 4;\n");
  printf ("    case 4: /* Signed Greater Than Mode */\n");
  printf ("      DSR |= DSR >> 7 & 1;\n");
  printf ("    case 4: /* Signed Greater Than Or Equal Mode */\n");
  printf ("      DSR |= greater_equal >> 7;\n");
  printf ("    }\n");
  printf (" assign_z:\n");
  printf ("  if (0xa05f >> z & 1)\n");
  printf ("    {\n");
  printf ("      RAISE_EXCEPTION (SIGILL);\n");
  printf ("      return;\n");
  printf ("    }\n");
  printf ("  DSP_R (z) = res;\n");
  printf ("  DSP_GRD (z) = res_grd;\n");
  printf ("}\n");
}

int
main (ac, av)
     int ac;
     char **av;
{
  /* verify the table before anything else */
  {
    op *p;
    for (p = tab; p->name; p++)
      {
	/* check that the code field contains 16 bits */
	if (strlen (p->code) != 16)
	  {
	    fprintf (stderr, "Code `%s' length wrong (%d) for `%s'\n",
		     p->code, strlen (p->code), p->name);
	    abort ();
	  }
      }
  }

  /* now generate the requested data */
  if (ac > 1)
    {
      if (strcmp (av[1], "-t") == 0)
	{
	  gengastab ();
	}
      else if (strcmp (av[1], "-d") == 0)
	{
	  gendefines ();
	}
      else if (strcmp (av[1], "-s") == 0)
	{
	  filltable (tab);
	  dumptable ("sh_jump_table", 1 << 16, 0);

	  memset (table, 0, sizeof table);
	  filltable (movsxy_tab);
	  ppi_moves ();
	  dumptable ("sh_dsp_table", 1 << 12, 0xf000);

	  memset (table, 0, sizeof table);
	  ppi_filltable ();
	  dumptable ("ppi_table", 1 << 8, 0);
	}
      else if (strcmp (av[1], "-x") == 0)
	{
	  filltable (tab);
	  filltable (movsxy_tab);
	  gensim ();
	}
      else if (strcmp (av[1], "-p") == 0)
	{
	  ppi_filltable ();
	  ppi_gensim ();
	}
    }
  else
    fprintf (stderr, "Opcode table generation no longer supported.\n");
  return 0;
}