toplev.c

gcc库的原代码,对编程有很大帮助.

	v_warning_with_decl (decl, s, ap);
    }
}

void
pedwarn_with_decl VPROTO((tree decl, char *s, ...))
{
#ifndef __STDC__
  tree decl;
  char *s;
#endif
  va_list ap;

  VA_START (ap, s);

#ifndef __STDC__
  decl = va_arg (ap, tree);
  s = va_arg (ap, char *);
#endif

  v_pedwarn_with_decl (decl, s, ap);
  va_end (ap);
}

static void
v_pedwarn_with_file_and_line (file, line, s, ap)
     char *file;
     int line;
     char *s;
     va_list ap;
{
  if (flag_pedantic_errors)
    v_error_with_file_and_line (file, line, s, ap);
  else
    v_warning_with_file_and_line (file, line, s, ap);
}

void
pedwarn_with_file_and_line VPROTO((char *file, int line, char *s, ...))
{
#ifndef __STDC__
  char *file;
  int line;
  char *s;
#endif
  va_list ap;

  VA_START (ap, s);

#ifndef __STDC__
  file = va_arg (ap, char *);
  line = va_arg (ap, int);
  s = va_arg (ap, char *);
#endif

  v_pedwarn_with_file_and_line (file, line, s, ap);
  va_end (ap);
}

/* Apologize for not implementing some feature.  */

static void
vsorry (s, ap)
     char *s;
     va_list ap;
{
  sorrycount++;
  if (input_filename)
    fprintf (stderr, "%s:%d: ", input_filename, lineno);
  else
    fprintf (stderr, "%s: ", progname);
  vmessage ("sorry, not implemented", s, ap);
  fputc ('\n', stderr);
}

void
sorry VPROTO((char *s, ...))
{
#ifndef __STDC__
  char *s;
#endif
  va_list ap;

  VA_START (ap, s);

#ifndef __STDC__
  s = va_arg (ap, char *);
#endif

  vsorry (s, ap);
  va_end (ap);
}

/* Apologize for not implementing some feature, then quit.  */

static void
v_really_sorry (s, ap)
     char *s;
     va_list ap;
{
  sorrycount++;
  if (input_filename)
    fprintf (stderr, "%s:%d: ", input_filename, lineno);
  else
    fprintf (stderr, "%s: ", progname);
  vmessage ("sorry, not implemented", s, ap);
  fatal (" (fatal)\n");
}

void
really_sorry VPROTO((char *s, ...))
{
#ifndef __STDC__
  char *s;
#endif
  va_list ap;

  VA_START (ap, s);

#ifndef __STDC__
  s = va_arg (ap, char *);
#endif

  v_really_sorry (s, ap);
  va_end (ap);
}

/* More 'friendly' abort that prints the line and file.
   config.h can #define abort fancy_abort if you like that sort of thing.

   I don't think this is actually a good idea.
   Other sorts of crashes will look a certain way.
   It is a good thing if crashes from calling abort look the same way.
     -- RMS  */

void
fancy_abort ()
{
  fatal ("internal gcc abort");
}

/* This calls abort and is used to avoid problems when abort if a macro.
   It is used when we need to pass the address of abort.  */

void
do_abort ()
{
  abort ();
}

/* When `malloc.c' is compiled with `rcheck' defined,
   it calls this function to report clobberage.  */

void
botch (s)
{
  abort ();
}

/* Same as `malloc' but report error if no memory available.  */

char *
xmalloc (size)
     unsigned size;
{
  register char *value = (char *) malloc (size);
  if (value == 0)
    fatal ("virtual memory exhausted");
  return value;
}

/* Same as `realloc' but report error if no memory available.  */

char *
xrealloc (ptr, size)
     char *ptr;
     int size;
{
  char *result = (char *) realloc (ptr, size);
  if (!result)
    fatal ("virtual memory exhausted");
  return result;
}

/* Return the logarithm of X, base 2, considering X unsigned,
   if X is a power of 2.  Otherwise, returns -1.

   This should be used via the `exact_log2' macro.  */

int
exact_log2_wide (x)
     register unsigned HOST_WIDE_INT x;
{
  register int log = 0;
  /* Test for 0 or a power of 2.  */
  if (x == 0 || x != (x & -x))
    return -1;
  while ((x >>= 1) != 0)
    log++;
  return log;
}

/* Given X, an unsigned number, return the largest int Y such that 2**Y <= X.
   If X is 0, return -1.

   This should be used via the floor_log2 macro.  */

int
floor_log2_wide (x)
     register unsigned HOST_WIDE_INT x;
{
  register int log = -1;
  while (x != 0)
    log++,
    x >>= 1;
  return log;
}

int float_handled;
jmp_buf float_handler;

/* Specify where to longjmp to when a floating arithmetic error happens.
   If HANDLER is 0, it means don't handle the errors any more.  */

void
set_float_handler (handler)
     jmp_buf handler;
{
  float_handled = (handler != 0);
  if (handler)
    bcopy ((char *) handler, (char *) float_handler, sizeof (float_handler));
}

/* Specify, in HANDLER, where to longjmp to when a floating arithmetic
   error happens, pushing the previous specification into OLD_HANDLER.
   Return an indication of whether there was a previous handler in effect.  */

int
push_float_handler (handler, old_handler)
     jmp_buf handler, old_handler;
{
  int was_handled = float_handled;

  float_handled = 1;
  if (was_handled)
    bcopy ((char *) float_handler, (char *) old_handler,
	   sizeof (float_handler));

  bcopy ((char *) handler, (char *) float_handler, sizeof (float_handler));
  return was_handled;
}

/* Restore the previous specification of whether and where to longjmp to
   when a floating arithmetic error happens.  */

void
pop_float_handler (handled, handler)
     int handled;
     jmp_buf handler;
{
  float_handled = handled;
  if (handled)
    bcopy ((char *) handler, (char *) float_handler, sizeof (float_handler));
}

/* Signals actually come here.  */

static void
float_signal (signo)
     /* If this is missing, some compilers complain.  */
     int signo;
{
  if (float_handled == 0)
    abort ();
#if defined (USG) || defined (hpux)
  signal (SIGFPE, float_signal);  /* re-enable the signal catcher */
#endif
  float_handled = 0;
  signal (SIGFPE, float_signal);
  longjmp (float_handler, 1);
}

/* Handler for SIGPIPE.  */

static void
pipe_closed (signo)
     /* If this is missing, some compilers complain.  */
     int signo;
{
  fatal ("output pipe has been closed");
}

/* Strip off a legitimate source ending from the input string NAME of
   length LEN.  Rather than having to know the names used by all of
   our front ends, we strip off an ending of a period followed by one,
   two, or three characters.  */

void
strip_off_ending (name, len)
     char *name;
     int len;
{
  if (len > 2 && name[len - 2] == '.')
    name[len - 2] = '\0';
  else if (len > 3 && name[len - 3] == '.')
    name[len - 3] = '\0';
  else if (len > 4 && name[len - 4] == '.')
    name[len - 4] = '\0';
}

/* Output a quoted string.  */
void
output_quoted_string (asm_file, string)
     FILE *asm_file;
     char *string;
{
  char c;

  putc ('\"', asm_file);
  while ((c = *string++) != 0)
    {
      if (c == '\"' || c == '\\')
	putc ('\\', asm_file);
      putc (c, asm_file);
    }
  putc ('\"', asm_file);
}

/* Output a file name in the form wanted by System V.  */

void
output_file_directive (asm_file, input_name)
     FILE *asm_file;
     char *input_name;
{
  int len = strlen (input_name);
  char *na = input_name + len;

  /* NA gets INPUT_NAME sans directory names.  */
  while (na > input_name)
    {
      if (na[-1] == '/')
	break;
      na--;
    }

#ifdef ASM_OUTPUT_MAIN_SOURCE_FILENAME
  ASM_OUTPUT_MAIN_SOURCE_FILENAME (asm_file, na);
#else
#ifdef ASM_OUTPUT_SOURCE_FILENAME
  ASM_OUTPUT_SOURCE_FILENAME (asm_file, na);
#else
  fprintf (asm_file, "\t.file\t");
  output_quoted_string (asm_file, na);
  fputc ('\n', asm_file);
#endif
#endif
}

/* Routine to build language identifier for object file. */
static void
output_lang_identify (asm_out_file)
     FILE *asm_out_file;
{
  int len = strlen (lang_identify ()) + sizeof ("__gnu_compiled_") + 1;
  char *s = (char *) alloca (len);
  sprintf (s, "__gnu_compiled_%s", lang_identify ());
  ASM_OUTPUT_LABEL (asm_out_file, s);
}

/* Routine to open a dump file.  */
static FILE *
open_dump_file (base_name, suffix)
     char *base_name;
     char *suffix;
{
  FILE *f;
  char *dumpname = (char *) alloca (strlen (base_name) + strlen (suffix) + 1);

  strcpy (dumpname, base_name);
  strcat (dumpname, suffix);
  f = fopen (dumpname, "w");
  if (f == 0)
    pfatal_with_name (dumpname);
  return f;
}

/* Compile an entire file of output from cpp, named NAME.
   Write a file of assembly output and various debugging dumps.  */

static void
compile_file (name)
     char *name;
{
  tree globals;
  int start_time;

  int name_specified = name != 0;

  if (dump_base_name == 0)
    dump_base_name = name ? name : "gccdump";

  parse_time = 0;
  varconst_time = 0;
  integration_time = 0;
  jump_time = 0;
  cse_time = 0;
  loop_time = 0;
  cse2_time = 0;
  flow_time = 0;
  combine_time = 0;
  sched_time = 0;
  local_alloc_time = 0;
  global_alloc_time = 0;
  sched2_time = 0;
  dbr_sched_time = 0;
  shorten_branch_time = 0;
  stack_reg_time = 0;
  final_time = 0;
  symout_time = 0;
  dump_time = 0;

  /* Open input file.  */

  if (name == 0 || !strcmp (name, "-"))
    {
      finput = stdin;
      name = "stdin";
    }
  else
    finput = fopen (name, "r");
  if (finput == 0)
    pfatal_with_name (name);

#ifdef IO_BUFFER_SIZE
  setvbuf (finput, (char *) xmalloc (IO_BUFFER_SIZE), _IOFBF, IO_BUFFER_SIZE);
#endif

  /* Initialize data in various passes.  */

  init_obstacks ();
  init_tree_codes ();
  init_lex ();
  /* Some of these really don't need to be called when generating bytecode,
     but the options would have to be parsed first to know that. -bson */
  init_rtl ();
  init_emit_once (debug_info_level == DINFO_LEVEL_NORMAL
		  || debug_info_level == DINFO_LEVEL_VERBOSE);
  init_regs ();
  init_decl_processing ();
  init_optabs ();
  init_stmt ();
  init_expmed ();
  init_expr_once ();
  init_loop ();
  init_reload ();

  if (flag_caller_saves)
    init_caller_save ();

  /* If auxiliary info generation is desired, open the output file.
     This goes in the same directory as the source file--unlike
     all the other output files.  */
  if (flag_gen_aux_info)
    {
      aux_info_file = fopen (aux_info_file_name, "w");
      if (aux_info_file == 0)
	pfatal_with_name (aux_info_file_name);
    }

  /* If rtl dump desired, open the output file.  */
  if (rtl_dump)
    rtl_dump_file = open_dump_file (dump_base_name, ".rtl");

  /* If jump_opt dump desired, open the output file.  */
  if (jump_opt_dump)
    jump_opt_dump_file = open_dump_file (dump_base_name, ".jump");

  /* If cse dump desired, open the output file.  */
  if (cse_dump)
    cse_dump_file = open_dump_file (dump_base_name, ".cse");

  /* If loop dump desired, open the output file.  */
  if (loop_dump)
    loop_dump_file = open_dump_file (dump_base_name, ".loop");

  /* If cse2 dump desired, open the output file.  */
  if (cse2_dump)
    cse2_dump_file = open_dump_file (dump_base_name, ".cse2");

  /* If flow dump desired, open the output file.  */
  if (flow_dump)
    flow_dump_file = open_dump_file (dump_base_name, ".flow");

  /* If combine dump desired, open the output file.  */
  if (combine_dump)
    combine_dump_file = open_dump_file (dump_base_name, ".combine");

  /* If scheduling dump desired, open the output file.  */
  if (sched_dump)
    sched_dump_file = open_dump_file (dump_base_name, ".sched");

  /* If local_reg dump desired, open the output file.  */
  if (local_reg_dump)
    local_reg_dump_file = open_dump_file (dump_base_name, ".lreg");

  /* If global_reg dump desired, open the output file.  */
  if (global_reg_dump)
    global_reg_dump_file = open_dump_file (dump_base_name, ".greg");

  /* If 2nd scheduling dump desired, open the output file.  */
  if (sched2_dump)
    sched2_dump_file = open_dump_file (dump_base_name, ".sched2");

  /* If jump2_opt dump desired, open the output file.  */
  if (jump2_opt_dump)
    jump2_opt_dump_file = open_dump_file (dump_base_name, ".jump2");

  /* If dbr_sched dump desired, open the output file.  */
  if (dbr_sched_dump)
    dbr_sched_dump_file = open_dump_file (dump_base_name, ".dbr");

#ifdef STACK_REGS