i370.c

gcc-2.95.3 Linux下最常用的C编译器

   and branch on register must be generated.
   ID is the label number of the label being checked.  */

int
mvs_check_label (id)
     int id;
{
  label_node_t *lp;

  for (lp = label_anchor; lp; lp = lp->label_next)
    {
      if (lp->label_id == id)
	return 1;
    }
  return 0;
}

/* The label list for the current page freed by linking the list onto the free
   label element chain.  */

int
mvs_free_label (void)
{
  if (label_anchor)
    {
      if (free_anchor)
	label_anchor->label_next = free_anchor;
      free_anchor = label_anchor;
    }
  label_anchor = 0;
}

/* If the page size limit is reached a new code page is started, and the base
   register is set to it.  This page break point is counted conservatively,
   most literals that have the same value are collapsed by the assembler.
   True is returned when a new page is started.
   FILE is the assembler output file descriptor.
   CODE is the length, in bytes, of the instruction to be emitted.
   LIT is the length of the literal to be emitted.  */

int
mvs_check_page (file, code, lit)
     FILE *file;
     int code, lit;
{
  if (file)
    assembler_source = file;

  if (mvs_page_code + code + mvs_page_lit + lit > MAX_MVS_PAGE_LENGTH)
    {
      fprintf (assembler_source, "\tB\tPGE%d\n", mvs_page_num);
      fprintf (assembler_source, "\tDS\t0F\n");
      fprintf (assembler_source, "\tLTORG\n");
      fprintf (assembler_source, "\tDS\t0F\n");
      fprintf (assembler_source, "PGE%d\tEQU\t*\n", mvs_page_num);
      fprintf (assembler_source, "\tDROP\t%d\n", BASE_REGISTER);
      mvs_page_num++;
      fprintf (assembler_source, "\tBALR\t%d,0\n", BASE_REGISTER);
      fprintf (assembler_source, "PG%d\tEQU\t*\n", mvs_page_num);
      fprintf (assembler_source, "\tUSING\t*,%d\n", BASE_REGISTER);
      mvs_free_label ();
      mvs_page_code = code;
      mvs_page_lit = lit;
      return 1;
    }
  mvs_page_code += code;
  mvs_page_lit += lit;
  return 0;
}

/* Check for C/370 runtime function, they don't use standard calling
   conventions.  True is returned if the function is in the table.
   NAME is the name of the current function.  */

int
mvs_function_check (name)
     char *name;
{
  int lower, middle, upper;
  int i;

  lower = 0;
  upper = MVS_FUNCTION_TABLE_LENGTH - 1;
  while (lower <= upper)
    {
      middle = (lower + upper) / 2;
      i = strcmp (name, mvs_function_table[middle]);
      if (i == 0)
	return 1;
      if (i < 0)
	upper = middle - 1;
      else
	lower = middle + 1;
    }
  return 0;
}


/* Return 1 if OP is a valid S operand for an RS, SI or SS type instruction.
   OP is the current operation.
   MODE is the current operation mode.  */

int
s_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  extern int volatile_ok;
  register enum rtx_code code = GET_CODE (op);

  if (CONSTANT_ADDRESS_P (op))
    return 1;
  if (mode == VOIDmode || GET_MODE (op) != mode)
    return 0;
  if (code == MEM)
    {
      register rtx x = XEXP (op, 0);

      if (!volatile_ok && op->volatil)
	return 0;
      if (REG_P (x) && REG_OK_FOR_BASE_P (x))
	return 1;
      if (GET_CODE (x) == PLUS
	  && REG_P (XEXP (x, 0)) && REG_OK_FOR_BASE_P (XEXP (x, 0))
	  && GET_CODE (XEXP (x, 1)) == CONST_INT
	  && (unsigned) INTVAL (XEXP (x, 1)) < 4096)
	return 1;
    }
  return 0;
}


/* Return 1 if OP is a valid R or S operand for an RS, SI or SS type
   instruction.
   OP is the current operation.
   MODE is the current operation mode.  */

int
r_or_s_operand (op, mode)
     register rtx op;
     enum machine_mode mode;
{
  extern int volatile_ok;
  register enum rtx_code code = GET_CODE (op);

  if (CONSTANT_ADDRESS_P (op))
    return 1;
  if (mode == VOIDmode || GET_MODE (op) != mode)
    return 0;
  if (code == REG)
    return 1;
  else if (code == MEM)
    {
      register rtx x = XEXP (op, 0);

      if (!volatile_ok && op->volatil)
	return 0;
      if (REG_P (x) && REG_OK_FOR_BASE_P (x))
	return 1;
      if (GET_CODE (x) == PLUS
	  && REG_P (XEXP (x, 0)) && REG_OK_FOR_BASE_P (XEXP (x, 0))
	  && GET_CODE (XEXP (x, 1)) == CONST_INT
	  && (unsigned) INTVAL (XEXP (x, 1)) < 4096)
	return 1;
    }
  return 0;
}


/* Return 1 if the next instruction is an unsigned jump instruction.
   INSN is the current instruction.  */

unsigned_jump_follows_p (insn)
     register rtx insn;
{
  insn = NEXT_INSN (insn);
  if (GET_CODE (insn) != JUMP_INSN)
    return 0;

  insn = XEXP (insn, 3);
  if (GET_CODE (insn) != SET)
    return 0;

  if (GET_CODE (XEXP (insn, 0)) != PC)
    return 0;

  insn = XEXP (insn, 1);
  if (GET_CODE (insn) != IF_THEN_ELSE)
    return 0;

  insn = XEXP (insn, 0);
  return GET_CODE (insn) != GE && GET_CODE (insn) != GT
    && GET_CODE (insn) != LE && GET_CODE (insn) != LT;
}

void
i370_function_prolog (f, l)
     FILE *f;
     int l;
{
#if MACROPROLOGUE == 1
  fprintf (f, "\tEDCPRLG USRDSAL=%d,BASEREG=%d\n",
	   STACK_POINTER_OFFSET + l - 120 +
	   current_function_outgoing_args_size, BASE_REGISTER);
  fprintf (f, "PG%d\tEQU\t*\n", mvs_page_num );
  fprintf (f, "\tLR\t11,1\n");
  fprintf (f, "\tL\t%d,=A(PGT%d)\n", PAGE_REGISTER, mvs_page_num);
  mvs_page_code = 6;
  mvs_page_lit = 4;
  mvs_check_page (f, 0, 0);
  function_base_page = mvs_page_num;
#else /* MACROPROLOGUE != 1 */
  static int function_label_index = 1;
  static int function_first = 0;
  static int function_year, function_month, function_day;
  static int function_hour, function_minute, function_second;
  int i;
  if (!function_first)
    {
      struct tm *function_time;
      time_t lcltime;
      time (&lcltime);
      function_time = localtime (&lcltime);
      function_year = function_time->tm_year + 1900;
      function_month = function_time->tm_mon + 1;
      function_day = function_time->tm_mday;
      function_hour = function_time->tm_hour;
      function_minute = function_time->tm_min;
      function_second = function_time->tm_sec;
      fprintf (f, "PPA2\tDS\t0F\n");
      fprintf (f, "\tDC\tX'03',X'00',X'33',X'00'\n");
      fprintf (f, "\tDC\tV(CEESTART),A(0)\n");
      fprintf (f, "\tDC\tA(CEETIMES)\n");
      fprintf (f, "CEETIMES\tDS\t0F\n");
      fprintf (f, "\tDC\tCL4'%d',CL4'%02d%02d',CL6'%02d%02d00'\n",
    		 function_year, function_month, function_day,
    		 function_hour, function_minute, function_second);
      fprintf (f, "\tDC\tCL2'01',CL4'0100'\n");
    }
  fprintf (f, "$DSD%03d\tDSECT\n", function_label_index);
  fprintf (f, "\tDS\tD\n");
  fprintf (f, "\tDS\tCL(%d)\n", STACK_POINTER_OFFSET + l
			+ current_function_outgoing_args_size);
  fprintf (f, "\tORG\t$DSD%03d\n", function_label_index);
  fprintf (f, "\tDS\tCL(120+8)\n");
  fprintf (f, "\tORG\n");
  fprintf (f, "\tDS\t0D\n");
  fprintf (f, "$DSL%03d\tEQU\t*-$DSD%03d-8\n", function_label_index,
	   function_label_index);
  fprintf (f, "\tDS\t0H\n");
  assemble_name (f, mvs_function_name);
  fprintf (f, "\tEQU\t*\n");
  fprintf (f, "\tUSING\t*,15\n");
  fprintf (f, "\tB\tFPL%03d\n", function_label_index);
  fprintf (f, "\tDC\tAL1(FPL%03d+4-*)\n", function_label_index + 1);
  fprintf (f, "\tDC\tX'CE',X'A0',AL1(16)\n");
  fprintf (f, "\tDC\tAL4(PPA2)\n");
  fprintf (f, "\tDC\tAL4(0)\n");
  fprintf (f, "\tDC\tAL4($DSL%03d)\n", function_label_index);
  fprintf (f, "FPL%03d\tEQU\t*\n", function_label_index + 1);
  fprintf (f, "\tDC\tAL2(%d),C'%s'\n", strlen (mvs_function_name),
	mvs_function_name);
  fprintf (f, "FPL%03d\tDS\t0H\n", function_label_index);
  fprintf (f, "\tSTM\t14,12,12(13)\n");
  fprintf (f, "\tL\t2,76(,13)\n");
  fprintf (f, "\tL\t0,16(,15)\n");
  fprintf (f, "\tALR\t0,2\n");
  fprintf (f, "\tCL\t0,12(,12)\n");
  fprintf (f, "\tBNH\t*+10\n");
  fprintf (f, "\tL\t15,116(,12)\n");
  fprintf (f, "\tBALR\t14,15\n");
  fprintf (f, "\tL\t15,72(,13)\n");
  fprintf (f, "\tSTM\t15,0,72(2)\n");
  fprintf (f, "\tMVI\t0(2),X'10'\n");
  fprintf (f, "\tST\t2,8(,13)\n ");
  fprintf (f, "\tST\t13,4(,2)\n ");
  fprintf (f, "\tLR\t13,2\n");
  fprintf (f, "\tDROP\t15\n");
  fprintf (f, "\tBALR\t%d,0\n", BASE_REGISTER);
  fprintf (f, "PG%d\tEQU\t*\n", mvs_page_num );
  fprintf (f, "\tUSING\t*,%d\n", BASE_REGISTER);
  fprintf (f, "\tLR\t11,1\n");
  fprintf (f, "\tL\t%d,=A(PGT%d)\n", PAGE_REGISTER, mvs_page_num);
  mvs_page_code = 4;
  mvs_page_lit = 4;
  mvs_check_page (f, 0, 0);
  function_base_page = mvs_page_num;
  function_first = 1;
  function_label_index += 2;
#endif /* MACROPROLOGUE */
}