cexp.c

这是完整的gcc源代码

      if (yystacksize > YYMAXDEPTH)
	yystacksize = YYMAXDEPTH;
      yyss = (short *) alloca (yystacksize * sizeof (*yyssp));
      __yy_bcopy ((char *)yyss1, (char *)yyss, size * sizeof (*yyssp));
      yyvs = (YYSTYPE *) alloca (yystacksize * sizeof (*yyvsp));
      __yy_bcopy ((char *)yyvs1, (char *)yyvs, size * sizeof (*yyvsp));
#ifdef YYLSP_NEEDED
      yyls = (YYLTYPE *) alloca (yystacksize * sizeof (*yylsp));
      __yy_bcopy ((char *)yyls1, (char *)yyls, size * sizeof (*yylsp));
#endif
#endif /* no yyoverflow */

      yyssp = yyss + size - 1;
      yyvsp = yyvs + size - 1;
#ifdef YYLSP_NEEDED
      yylsp = yyls + size - 1;
#endif

#if YYDEBUG != 0
      if (yydebug)
	fprintf(stderr, "Stack size increased to %d\n", yystacksize);
#endif

      if (yyssp >= yyss + yystacksize - 1)
	YYABORT;
    }

#if YYDEBUG != 0
  if (yydebug)
    fprintf(stderr, "Entering state %d\n", yystate);
#endif

 yybackup:

/* Do appropriate processing given the current state.  */
/* Read a lookahead token if we need one and don't already have one.  */
/* yyresume: */

  /* First try to decide what to do without reference to lookahead token.  */

  yyn = yypact[yystate];
  if (yyn == YYFLAG)
    goto yydefault;

  /* Not known => get a lookahead token if don't already have one.  */

  /* yychar is either YYEMPTY or YYEOF
     or a valid token in external form.  */

  if (yychar == YYEMPTY)
    {
#if YYDEBUG != 0
      if (yydebug)
	fprintf(stderr, "Reading a token: ");
#endif
      yychar = YYLEX;
    }

  /* Convert token to internal form (in yychar1) for indexing tables with */

  if (yychar <= 0)		/* This means end of input. */
    {
      yychar1 = 0;
      yychar = YYEOF;		/* Don't call YYLEX any more */

#if YYDEBUG != 0
      if (yydebug)
	fprintf(stderr, "Now at end of input.\n");
#endif
    }
  else
    {
      yychar1 = YYTRANSLATE(yychar);

#if YYDEBUG != 0
      if (yydebug)
	fprintf(stderr, "Next token is %d (%s)\n", yychar, yytname[yychar1]);
#endif
    }

  yyn += yychar1;
  if (yyn < 0 || yyn > YYLAST || yycheck[yyn] != yychar1)
    goto yydefault;

  yyn = yytable[yyn];

  /* yyn is what to do for this token type in this state.
     Negative => reduce, -yyn is rule number.
     Positive => shift, yyn is new state.
       New state is final state => don't bother to shift,
       just return success.
     0, or most negative number => error.  */

  if (yyn < 0)
    {
      if (yyn == YYFLAG)
	goto yyerrlab;
      yyn = -yyn;
      goto yyreduce;
    }
  else if (yyn == 0)
    goto yyerrlab;

  if (yyn == YYFINAL)
    YYACCEPT;

  /* Shift the lookahead token.  */

#if YYDEBUG != 0
  if (yydebug)
    fprintf(stderr, "Shifting token %d (%s), ", yychar, yytname[yychar1]);
#endif

  /* Discard the token being shifted unless it is eof.  */
  if (yychar != YYEOF)
    yychar = YYEMPTY;

  *++yyvsp = yylval;
#ifdef YYLSP_NEEDED
  *++yylsp = yylloc;
#endif

  /* count tokens shifted since error; after three, turn off error status.  */
  if (yyerrstatus) yyerrstatus--;

  yystate = yyn;
  goto yynewstate;

/* Do the default action for the current state.  */
yydefault:

  yyn = yydefact[yystate];
  if (yyn == 0)
    goto yyerrlab;

/* Do a reduction.  yyn is the number of a rule to reduce with.  */
yyreduce:
  yylen = yyr2[yyn];
  yyval = yyvsp[1-yylen]; /* implement default value of the action */

#if YYDEBUG != 0
  if (yydebug)
    {
      int i;

      fprintf (stderr, "Reducing via rule %d (line %d), ",
	       yyn, yyrline[yyn]);

      /* Print the symboles being reduced, and their result.  */
      for (i = yyprhs[yyn]; yyrhs[i] > 0; i++)
	fprintf (stderr, "%s ", yytname[yyrhs[i]]);
      fprintf (stderr, " -> %s\n", yytname[yyr1[yyn]]);
    }
#endif


  switch (yyn) {

case 1:
#line 75 "./cexp.y"
{ expression_value = yyvsp[0].integer.value; ;
    break;}
case 3:
#line 81 "./cexp.y"
{ yyval.integer = yyvsp[0].integer; ;
    break;}
case 4:
#line 86 "./cexp.y"
{ yyval.integer.value = - yyvsp[0].integer.value;
			  yyval.integer.unsignedp = yyvsp[0].integer.unsignedp; ;
    break;}
case 5:
#line 89 "./cexp.y"
{ yyval.integer.value = ! yyvsp[0].integer.value;
			  yyval.integer.unsignedp = 0; ;
    break;}
case 6:
#line 92 "./cexp.y"
{ yyval.integer = yyvsp[0].integer; ;
    break;}
case 7:
#line 94 "./cexp.y"
{ yyval.integer.value = ~ yyvsp[0].integer.value;
			  yyval.integer.unsignedp = yyvsp[0].integer.unsignedp; ;
    break;}
case 8:
#line 97 "./cexp.y"
{ yyval.integer = yyvsp[-1].integer; ;
    break;}
case 9:
#line 102 "./cexp.y"
{ yyval.integer.unsignedp = yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp;
			  if (yyval.integer.unsignedp)
			    yyval.integer.value = (unsigned) yyvsp[-2].integer.value * yyvsp[0].integer.value;
			  else
			    yyval.integer.value = yyvsp[-2].integer.value * yyvsp[0].integer.value; ;
    break;}
case 10:
#line 108 "./cexp.y"
{ if (yyvsp[0].integer.value == 0)
			    {
			      error ("division by zero in #if");
			      yyvsp[0].integer.value = 1;
			    }
			  yyval.integer.unsignedp = yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp;
			  if (yyval.integer.unsignedp)
			    yyval.integer.value = (unsigned) yyvsp[-2].integer.value / yyvsp[0].integer.value;
			  else
			    yyval.integer.value = yyvsp[-2].integer.value / yyvsp[0].integer.value; ;
    break;}
case 11:
#line 119 "./cexp.y"
{ if (yyvsp[0].integer.value == 0)
			    {
			      error ("division by zero in #if");
			      yyvsp[0].integer.value = 1;
			    }
			  yyval.integer.unsignedp = yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp;
			  if (yyval.integer.unsignedp)
			    yyval.integer.value = (unsigned) yyvsp[-2].integer.value % yyvsp[0].integer.value;
			  else
			    yyval.integer.value = yyvsp[-2].integer.value % yyvsp[0].integer.value; ;
    break;}
case 12:
#line 130 "./cexp.y"
{ yyval.integer.value = yyvsp[-2].integer.value + yyvsp[0].integer.value;
			  yyval.integer.unsignedp = yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp; ;
    break;}
case 13:
#line 133 "./cexp.y"
{ yyval.integer.value = yyvsp[-2].integer.value - yyvsp[0].integer.value;
			  yyval.integer.unsignedp = yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp; ;
    break;}
case 14:
#line 136 "./cexp.y"
{ yyval.integer.unsignedp = yyvsp[-2].integer.unsignedp;
			  if (yyval.integer.unsignedp)
			    yyval.integer.value = (unsigned) yyvsp[-2].integer.value << yyvsp[0].integer.value;
			  else
			    yyval.integer.value = yyvsp[-2].integer.value << yyvsp[0].integer.value; ;
    break;}
case 15:
#line 142 "./cexp.y"
{ yyval.integer.unsignedp = yyvsp[-2].integer.unsignedp;
			  if (yyval.integer.unsignedp)
			    yyval.integer.value = (unsigned) yyvsp[-2].integer.value >> yyvsp[0].integer.value;
			  else
			    yyval.integer.value = yyvsp[-2].integer.value >> yyvsp[0].integer.value; ;
    break;}
case 16:
#line 148 "./cexp.y"
{ yyval.integer.value = (yyvsp[-2].integer.value == yyvsp[0].integer.value);
			  yyval.integer.unsignedp = 0; ;
    break;}
case 17:
#line 151 "./cexp.y"
{ yyval.integer.value = (yyvsp[-2].integer.value != yyvsp[0].integer.value);
			  yyval.integer.unsignedp = 0; ;
    break;}
case 18:
#line 154 "./cexp.y"
{ yyval.integer.unsignedp = 0;
			  if (yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp)
			    yyval.integer.value = (unsigned) yyvsp[-2].integer.value <= yyvsp[0].integer.value;
			  else
			    yyval.integer.value = yyvsp[-2].integer.value <= yyvsp[0].integer.value; ;
    break;}
case 19:
#line 160 "./cexp.y"
{ yyval.integer.unsignedp = 0;
			  if (yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp)
			    yyval.integer.value = (unsigned) yyvsp[-2].integer.value >= yyvsp[0].integer.value;
			  else
			    yyval.integer.value = yyvsp[-2].integer.value >= yyvsp[0].integer.value; ;
    break;}
case 20:
#line 166 "./cexp.y"
{ yyval.integer.unsignedp = 0;
			  if (yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp)
			    yyval.integer.value = (unsigned) yyvsp[-2].integer.value < yyvsp[0].integer.value;
			  else
			    yyval.integer.value = yyvsp[-2].integer.value < yyvsp[0].integer.value; ;
    break;}
case 21:
#line 172 "./cexp.y"
{ yyval.integer.unsignedp = 0;
			  if (yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp)
			    yyval.integer.value = (unsigned) yyvsp[-2].integer.value > yyvsp[0].integer.value;
			  else
			    yyval.integer.value = yyvsp[-2].integer.value > yyvsp[0].integer.value; ;
    break;}
case 22:
#line 178 "./cexp.y"
{ yyval.integer.value = yyvsp[-2].integer.value & yyvsp[0].integer.value;
			  yyval.integer.unsignedp = yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp; ;
    break;}
case 23:
#line 181 "./cexp.y"
{ yyval.integer.value = yyvsp[-2].integer.value ^ yyvsp[0].integer.value;
			  yyval.integer.unsignedp = yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp; ;
    break;}
case 24:
#line 184 "./cexp.y"
{ yyval.integer.value = yyvsp[-2].integer.value | yyvsp[0].integer.value;
			  yyval.integer.unsignedp = yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp; ;
    break;}
case 25:
#line 187 "./cexp.y"
{ yyval.integer.value = (yyvsp[-2].integer.value && yyvsp[0].integer.value);
			  yyval.integer.unsignedp = 0; ;
    break;}
case 26:
#line 190 "./cexp.y"
{ yyval.integer.value = (yyvsp[-2].integer.value || yyvsp[0].integer.value);
			  yyval.integer.unsignedp = 0; ;
    break;}
case 27:
#line 193 "./cexp.y"
{ yyval.integer.value = yyvsp[-4].integer.value ? yyvsp[-2].integer.value : yyvsp[0].integer.value;
			  yyval.integer.unsignedp = yyvsp[-2].integer.unsignedp || yyvsp[0].integer.unsignedp; ;
    break;}
case 28:
#line 196 "./cexp.y"
{ yyval.integer = yylval.integer; ;
    break;}
case 29:
#line 198 "./cexp.y"
{ yyval.integer = yylval.integer; ;
    break;}
case 30:
#line 200 "./cexp.y"
{ yyval.integer.value = 0;
			  yyval.integer.unsignedp = 0; ;
    break;}
}
   /* the action file gets copied in in place of this dollarsign */
#line 423 "bison.simple"

  yyvsp -= yylen;
  yyssp -= yylen;
#ifdef YYLSP_NEEDED
  yylsp -= yylen;
#endif

#if YYDEBUG != 0
  if (yydebug)
    {
      short *ssp1 = yyss - 1;
      fprintf (stderr, "state stack now");
      while (ssp1 != yyssp)
	fprintf (stderr, " %d", *++ssp1);
      fprintf (stderr, "\n");
    }
#endif

  *++yyvsp = yyval;

#ifdef YYLSP_NEEDED
  yylsp++;
  if (yylen == 0)
    {
      yylsp->first_line = yylloc.first_line;
      yylsp->first_column = yylloc.first_column;
      yylsp->last_line = (yylsp-1)->last_line;
      yylsp->last_column = (yylsp-1)->last_column;
      yylsp->text = 0;
    }
  else
    {
      yylsp->last_line = (yylsp+yylen-1)->last_line;
      yylsp->last_column = (yylsp+yylen-1)->last_column;
    }
#endif

  /* Now "shift" the result of the reduction.
     Determine what state that goes to,
     based on the state we popped back to
     and the rule number reduced by.  */

  yyn = yyr1[yyn];

  yystate = yypgoto[yyn - YYNTBASE] + *yyssp;
  if (yystate >= 0 && yystate <= YYLAST && yycheck[yystate] == *yyssp)
    yystate = yytable[yystate];
  else
    yystate = yydefgoto[yyn - YYNTBASE];

  goto yynewstate;

yyerrlab:   /* here on detecting error */

  if (! yyerrstatus)
    /* If not already recovering from an error, report this error.  */
    {
      ++yynerrs;

#ifdef YYERROR_VERBOSE
      yyn = yypact[yystate];

      if (yyn > YYFLAG && yyn < YYLAST)
	{
	  int size = 0;
	  char *msg;
	  int x, count;

	  count = 0;
	  for (x = 0; x < (sizeof(yytname) / sizeof(char *)); x++)
	    if (yycheck[x + yyn] == x)
	      size += strlen(yytname[x]) + 15, count++;
	  msg = (char *) xmalloc(size + 15);
	  strcpy(msg, "parse error");

	  if (count < 5)
	    {
	      count = 0;
	      for (x = 0; x < (sizeof(yytname) / sizeof(char *)); x++)
		if (yycheck[x + yyn] == x)
		  {
		    strcat(msg, count == 0 ? ", expecting `" : " or `");
		    strcat(msg, yytname[x]);
		    strcat(msg, "'");
		    count++;
		  }
	    }
	  yyerror(msg);
	  free(msg);
	}
      else
#endif /* YYERROR_VERBOSE */
	yyerror("parse error");
    }

yyerrlab1:   /* here on error raised explicitly by an action */

  if (yyerrstatus == 3)
    {
      /* if just tried and failed to reuse lookahead token after an error, discard it.  */

      /* return failure if at end of input */
      if (yychar == YYEOF)
	YYABORT;

#if YYDEBUG != 0
      if (yydebug)
	fprintf(stderr, "Discarding token %d (%s).\n", yychar, yytname[yychar1]);
#endif

      yychar = YYEMPTY;
    }

  /* Else will try to reuse lookahead token
     after shifting the error token.  */

  yyerrstatus = 3;		/* Each real token shifted decrements this */

  goto yyerrhandle;

yyerrdefault:  /* current state does not do anything special for the error token. */

#if 0
  /* This is wrong; only states that explicitly want error tokens
     should shift them.  */
  yyn = yydefact[yystate];  /* If its default is to accept any token, ok.  Otherwise pop it.*/
  if (yyn) goto yydefault;
#endif

yyerrpop:   /* pop the current state because it cannot handle the error token */

  if (yyssp == yyss) YYABORT;
  yyvsp--;
  yystate = *--yyssp;
#ifdef YYLSP_NEEDED
  yylsp--;
#endif

#if YYDEBUG != 0
  if (yydebug)
    {
      short *ssp1 = yyss - 1;
      fprintf (stderr, "Error: state stack now");
      while (ssp1 != yyssp)
	fprintf (stderr, " %d", *++ssp1);
      fprintf (stderr, "\n");
    }
#endif

yyerrhandle:

  yyn = yypact[yystate];
  if (yyn == YYFLAG)