compilers/lcc/lburg/gram.y

   1 %{
   2 #include <stdio.h>
   3 #include "lburg.h"
   4 static char rcsid[] = "$Id: gram.y 145 2001-10-17 21:53:10Z timo $";
   5 /*lint -e616 -e527 -e652 -esym(552,yynerrs) -esym(563,yynewstate,yyerrlab) */
   6 static int yylineno = 0;
   7 %}
   8 %union {
   9         int n;
  10         char *string;
  11         Tree tree;
  12 }
  13 %term TERMINAL
  14 %term START
  15 %term PPERCENT
  16
  17 %token  <string>        ID TEMPLATE CODE
  18 %token  <n>             INT
  19 %type   <string>        nonterm cost
  20 %type   <tree>          tree
  21 %%
  22 spec    : decls PPERCENT rules          { yylineno = 0; }
  23         | decls                         { yylineno = 0; }
  24         ;
  25
  26 decls   : /* lambda */
  27         | decls decl
  28         ;
  29
  30 decl    : TERMINAL  blist '\n'
  31         | START nonterm '\n'            {
  32                 if (nonterm($2)->number != 1)
  33                         yyerror("redeclaration of the start symbol\n");
  34                 }
  35         | '\n'
  36         | error '\n'                    { yyerrok; }
  37         ;
  38
  39 blist   : /* lambda */
  40         | blist ID '=' INT              { term($2, $4); }
  41         ;
  42
  43 rules   : /* lambda */
  44         | rules nonterm ':' tree TEMPLATE cost '\n'     { rule($2, $4, $5, $6); }
  45         | rules '\n'
  46         | rules error '\n'              { yyerrok; }
  47         ;
  48
  49 nonterm : ID                            { nonterm($$ = $1); }
  50         ;
  51
  52 tree    : ID                            { $$ = tree($1,  0,  0); }
  53         | ID '(' tree ')'               { $$ = tree($1, $3,  0); }
  54         | ID '(' tree ',' tree ')'      { $$ = tree($1, $3, $5); }
  55         ;
  56
  57 cost    : CODE                          { if (*$1 == 0) $$ = "0"; }
  58         ;
  59 %%
  60 #include <assert.h>
  61 #include <stdarg.h>
  62 #include <ctype.h>
  63 #include <string.h>
  64 #include <limits.h>
  65
  66 int errcnt = 0;
  67 FILE *infp = NULL;
  68 FILE *outfp = NULL;
  69 static char buf[BUFSIZ], *bp = buf;
  70 static int ppercent = 0;
  71 static int code = 0;
  72
  73 static int get(void) {
  74         if (*bp == 0) {
  75                 bp = buf;
  76                 *bp = 0;
  77                 if (fgets(buf, sizeof buf, infp) == NULL)
  78                         return EOF;
  79                 yylineno++;
  80                 while (buf[0] == '%' && buf[1] == '{' && buf[2] == '\n') {
  81                         for (;;) {
  82                                 if (fgets(buf, sizeof buf, infp) == NULL) {
  83                                         yywarn("unterminated %{...%}\n");
  84                                         return EOF;
  85                                 }
  86                                 yylineno++;
  87                                 if (strcmp(buf, "%}\n") == 0)
  88                                         break;
  89                                 fputs(buf, outfp);
  90                         }
  91                         if (fgets(buf, sizeof buf, infp) == NULL)
  92                                 return EOF;
  93                         yylineno++;
  94                 }
  95         }
  96         return *bp++;
  97 }
  98
  99 void yyerror(char *fmt, ...) {
 100         va_list ap;
 101
 102         va_start(ap, fmt);
 103         if (yylineno > 0)
 104                 fprintf(stderr, "line %d: ", yylineno);
 105         vfprintf(stderr, fmt, ap);
 106         if (fmt[strlen(fmt)-1] != '\n')
 107                  fprintf(stderr, "\n");
 108         errcnt++;
 109         va_end(ap);
 110 }
 111
 112 int yylex(void) {
 113         int c;
 114
 115         if (code) {
 116                 char *p;
 117                 bp += strspn(bp, " \t\f");
 118                 p = strchr(bp, '\n');
 119                 if (p == NULL)
 120                         p = strchr(bp, '\n');
 121                 while (p > bp && isspace(p[-1]))
 122                         p--;
 123                 yylval.string = alloc(p - bp + 1);
 124                 strncpy(yylval.string, bp, p - bp);
 125                 yylval.string[p - bp] = 0;
 126                 bp = p;
 127                 code--;
 128                 return CODE;
 129         }
 130         while ((c = get()) != EOF) {
 131                 switch (c) {
 132                 case ' ': case '\f': case '\t':
 133                         continue;
 134                 case '\n':
 135                 case '(': case ')': case ',':
 136                 case ':': case '=':
 137                         return c;
 138                 }
 139                 if (c == '%' && *bp == '%') {
 140                         bp++;
 141                         return ppercent++ ? 0 : PPERCENT;
 142                 } else if (c == '%' && strncmp(bp, "term", 4) == 0
 143                 && isspace(bp[4])) {
 144                         bp += 4;
 145                         return TERMINAL;
 146                 } else if (c == '%' && strncmp(bp, "start", 5) == 0
 147                 && isspace(bp[5])) {
 148                         bp += 5;
 149                         return START;
 150                 } else if (c == '"') {
 151                         char *p = strchr(bp, '"');
 152                         if (p == NULL) {
 153                                 yyerror("missing \" in assembler template\n");
 154                                 p = strchr(bp, '\n');
 155                                 if (p == NULL)
 156                                         p = strchr(bp, '\0');
 157                         }
 158                         assert(p);
 159                         yylval.string = alloc(p - bp + 1);
 160                         strncpy(yylval.string, bp, p - bp);
 161                         yylval.string[p - bp] = 0;
 162                         bp = *p == '"' ? p + 1 : p;
 163                         code++;
 164                         return TEMPLATE;
 165                 } else if (isdigit(c)) {
 166                         int n = 0;
 167                         do {
 168                                 int d = c - '0';
 169                                 if (n > (INT_MAX - d)/10)
 170                                         yyerror("integer greater than %d\n", INT_MAX);
 171                                 else
 172                                         n = 10*n + d;
 173                                 c = get();
 174                         } while (c != EOF && isdigit(c));
 175                         bp--;
 176                         yylval.n = n;
 177                         return INT;
 178                 } else if (isalpha(c)) {
 179                         char *p = bp - 1;
 180                         while (isalpha(*bp) || isdigit(*bp) || *bp == '_')
 181                                 bp++;
 182                         yylval.string = alloc(bp - p + 1);
 183                         strncpy(yylval.string, p, bp - p);
 184                         yylval.string[bp - p] = 0;
 185                         return ID;
 186                 } else if (isprint(c))
 187                         yyerror("invalid character `%c'\n", c);
 188                 else
 189                         yyerror("invalid character `\\%03o'\n", (unsigned char)c);
 190         }
 191         return 0;
 192 }
 193
 194 void yywarn(char *fmt, ...) {
 195         va_list ap;
 196
 197         va_start(ap, fmt);
 198         if (yylineno > 0)
 199                 fprintf(stderr, "line %d: ", yylineno);
 200         fprintf(stderr, "warning: ");
 201         vfprintf(stderr, fmt, ap);
 202 }