diff options
Diffstat (limited to 'lcc/lburg/gram.y')
| -rwxr-xr-x | lcc/lburg/gram.y | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/lcc/lburg/gram.y b/lcc/lburg/gram.y new file mode 100755 index 0000000..860d22a --- /dev/null +++ b/lcc/lburg/gram.y @@ -0,0 +1,202 @@ +%{
+#include <stdio.h>
+#include "lburg.h"
+static char rcsid[] = "$Id: gram.y 145 2001-10-17 21:53:10Z timo $";
+/*lint -e616 -e527 -e652 -esym(552,yynerrs) -esym(563,yynewstate,yyerrlab) */
+static int yylineno = 0;
+%}
+%union {
+ int n;
+ char *string;
+ Tree tree;
+}
+%term TERMINAL
+%term START
+%term PPERCENT
+
+%token <string> ID TEMPLATE CODE
+%token <n> INT
+%type <string> nonterm cost
+%type <tree> tree
+%%
+spec : decls PPERCENT rules { yylineno = 0; }
+ | decls { yylineno = 0; }
+ ;
+
+decls : /* lambda */
+ | decls decl
+ ;
+
+decl : TERMINAL blist '\n'
+ | START nonterm '\n' {
+ if (nonterm($2)->number != 1)
+ yyerror("redeclaration of the start symbol\n");
+ }
+ | '\n'
+ | error '\n' { yyerrok; }
+ ;
+
+blist : /* lambda */
+ | blist ID '=' INT { term($2, $4); }
+ ;
+
+rules : /* lambda */
+ | rules nonterm ':' tree TEMPLATE cost '\n' { rule($2, $4, $5, $6); }
+ | rules '\n'
+ | rules error '\n' { yyerrok; }
+ ;
+
+nonterm : ID { nonterm($$ = $1); }
+ ;
+
+tree : ID { $$ = tree($1, 0, 0); }
+ | ID '(' tree ')' { $$ = tree($1, $3, 0); }
+ | ID '(' tree ',' tree ')' { $$ = tree($1, $3, $5); }
+ ;
+
+cost : CODE { if (*$1 == 0) $$ = "0"; }
+ ;
+%%
+#include <assert.h>
+#include <stdarg.h>
+#include <ctype.h>
+#include <string.h>
+#include <limits.h>
+
+int errcnt = 0;
+FILE *infp = NULL;
+FILE *outfp = NULL;
+static char buf[BUFSIZ], *bp = buf;
+static int ppercent = 0;
+static int code = 0;
+
+static int get(void) {
+ if (*bp == 0) {
+ bp = buf;
+ *bp = 0;
+ if (fgets(buf, sizeof buf, infp) == NULL)
+ return EOF;
+ yylineno++;
+ while (buf[0] == '%' && buf[1] == '{' && buf[2] == '\n') {
+ for (;;) {
+ if (fgets(buf, sizeof buf, infp) == NULL) {
+ yywarn("unterminated %{...%}\n");
+ return EOF;
+ }
+ yylineno++;
+ if (strcmp(buf, "%}\n") == 0)
+ break;
+ fputs(buf, outfp);
+ }
+ if (fgets(buf, sizeof buf, infp) == NULL)
+ return EOF;
+ yylineno++;
+ }
+ }
+ return *bp++;
+}
+
+void yyerror(char *fmt, ...) {
+ va_list ap;
+
+ va_start(ap, fmt);
+ if (yylineno > 0)
+ fprintf(stderr, "line %d: ", yylineno);
+ vfprintf(stderr, fmt, ap);
+ if (fmt[strlen(fmt)-1] != '\n')
+ fprintf(stderr, "\n");
+ errcnt++;
+ va_end(ap);
+}
+
+int yylex(void) {
+ int c;
+
+ if (code) {
+ char *p;
+ bp += strspn(bp, " \t\f");
+ p = strchr(bp, '\n');
+ if (p == NULL)
+ p = strchr(bp, '\n');
+ while (p > bp && isspace(p[-1]))
+ p--;
+ yylval.string = alloc(p - bp + 1);
+ strncpy(yylval.string, bp, p - bp);
+ yylval.string[p - bp] = 0;
+ bp = p;
+ code--;
+ return CODE;
+ }
+ while ((c = get()) != EOF) {
+ switch (c) {
+ case ' ': case '\f': case '\t':
+ continue;
+ case '\n':
+ case '(': case ')': case ',':
+ case ':': case '=':
+ return c;
+ }
+ if (c == '%' && *bp == '%') {
+ bp++;
+ return ppercent++ ? 0 : PPERCENT;
+ } else if (c == '%' && strncmp(bp, "term", 4) == 0
+ && isspace(bp[4])) {
+ bp += 4;
+ return TERMINAL;
+ } else if (c == '%' && strncmp(bp, "start", 5) == 0
+ && isspace(bp[5])) {
+ bp += 5;
+ return START;
+ } else if (c == '"') {
+ char *p = strchr(bp, '"');
+ if (p == NULL) {
+ yyerror("missing \" in assembler template\n");
+ p = strchr(bp, '\n');
+ if (p == NULL)
+ p = strchr(bp, '\0');
+ }
+ assert(p);
+ yylval.string = alloc(p - bp + 1);
+ strncpy(yylval.string, bp, p - bp);
+ yylval.string[p - bp] = 0;
+ bp = *p == '"' ? p + 1 : p;
+ code++;
+ return TEMPLATE;
+ } else if (isdigit(c)) {
+ int n = 0;
+ do {
+ int d = c - '0';
+ if (n > (INT_MAX - d)/10)
+ yyerror("integer greater than %d\n", INT_MAX);
+ else
+ n = 10*n + d;
+ c = get();
+ } while (c != EOF && isdigit(c));
+ bp--;
+ yylval.n = n;
+ return INT;
+ } else if (isalpha(c)) {
+ char *p = bp - 1;
+ while (isalpha(*bp) || isdigit(*bp) || *bp == '_')
+ bp++;
+ yylval.string = alloc(bp - p + 1);
+ strncpy(yylval.string, p, bp - p);
+ yylval.string[bp - p] = 0;
+ return ID;
+ } else if (isprint(c))
+ yyerror("invalid character `%c'\n", c);
+ else
+ yyerror("invalid character `\\%03o'\n", (unsigned char)c);
+ }
+ return 0;
+}
+
+void yywarn(char *fmt, ...) {
+ va_list ap;
+
+ va_start(ap, fmt);
+ if (yylineno > 0)
+ fprintf(stderr, "line %d: ", yylineno);
+ fprintf(stderr, "warning: ");
+ vfprintf(stderr, fmt, ap);
+}
|