gecko-dev/ef/Tools/Burg/fe.c

367 строки
7.0 KiB
C

char rcsid_fe[] = "$Id: fe.c,v 1.1 1998/12/17 06:36:47 fur%netscape.com Exp $";
#include <stdio.h>
#include <string.h>
#include "b.h"
#include "fe.h"
static int arity;
List ruleASTs;
static void doBinding ARGS((Binding));
static void doDecl ARGS((Arity));
static NonTerminal lookup ARGS((Pattern));
static NonTerminal normalize ARGS((PatternAST, NonTerminal, Pattern *));
static void doEnterNonTerm ARGS((RuleAST));
static void doRule ARGS((RuleAST));
static void doTable ARGS((Operator));
static void
doBinding(b) Binding b;
{
int new;
Symbol s;
s = enter(b->name, &new);
if (!new) {
fprintf(stderr, "Non-unique name: %s\n", b->name);
exit(1);
}
s->tag = OPERATOR;
s->u.op = newOperator(b->name, b->opnum, arity);
if (arity == 0) {
leaves = newList(s->u.op, leaves);
}
}
static void
doDecl(a) Arity a;
{
if (!a) {
return;
}
arity = a->arity;
foreachList((ListFn) doBinding, a->bindings);
}
static List xpatterns;
static int tcount;
static NonTerminal
lookup(p) Pattern p;
{
char buf[10];
char *s;
List l;
NonTerminal n;
DeltaCost dummy;
for (l = xpatterns; l; l = l->next) {
Pattern x = (Pattern) l->x;
if (x->op == p->op
&& x->children[0] == p->children[0]
&& x->children[1] == p->children[1]) {
return x->normalizer;
}
}
sprintf(buf, "n%%%d", tcount++);
s = (char *) zalloc(strlen(buf)+1);
strcpy(s, buf);
n = newNonTerminal(s);
p->normalizer = n;
xpatterns = newList(p, xpatterns);
ZEROCOST(dummy);
(void) newRule(dummy, 0, n, p);
return n;
}
static NonTerminal
normalize(ast, nt, patt) PatternAST ast; NonTerminal nt; Pattern *patt;
{
Symbol s;
int new;
Pattern dummy;
s = enter(ast->op, &new);
ast->sym = s;
if (new) {
fprintf(stderr, "Illegal use of %s --- undefined symbol\n", s->name);
exit(1);
return 0; /* shut up compilers */
} else if (s->tag == NONTERMINAL) {
if (ast->children) {
fprintf(stderr, "Illegal use of %s, a non-terminal, as a terminal\n", s->name);
exit(1);
}
*patt = newPattern(0);
(*patt)->children[0] = s->u.nt;
return s->u.nt;
} else {
s->u.op->ref = 1;
*patt = newPattern(s->u.op);
if (s->u.op->arity == -1) {
if (!ast->children) {
s->u.op->arity = 0;
leaves = newList(s->u.op, leaves);
} else if (!ast->children->next) {
s->u.op->arity = 1;
} else if (!ast->children->next->next) {
s->u.op->arity = 2;
} else {
fprintf(stderr, "ERROR: Too many children (max = 2) for \"%s\"\n", s->name);
exit(1);
}
if (s->u.op->arity > max_arity) {
max_arity = s->u.op->arity;
}
}
switch (s->u.op->arity) {
default:
assert(0);
break;
case 0:
if (ast->children) {
fprintf(stderr, "ERROR: Incorrect number of children for leaf operator, \"%s\"\n", s->name);
exit(1);
}
break;
case 1:
if (!ast->children || ast->children->next) {
fprintf(stderr, "ERROR: Incorrect number of children for unary operator, \"%s\"\n", s->name);
exit(1);
}
(*patt)->children[0] = normalize((PatternAST) ast->children->x, 0, &dummy);
break;
case 2:
if (!ast->children || !ast->children->next) {
fprintf(stderr, "ERROR: Incorrect number of children for binary operator, \"%s\"\n", s->name);
exit(1);
}
(*patt)->children[0] = normalize((PatternAST) ast->children->x, 0, &dummy);
(*patt)->children[1] = normalize((PatternAST) ast->children->next->x, 0, &dummy);
break;
}
if (nt) {
(*patt)->normalizer = nt;
return nt;
} else {
return lookup(*patt);
}
}
}
static void
doEnterNonTerm(ast) RuleAST ast;
{
int new;
Symbol s;
DeltaCost delta;
int i;
IntList p;
s = enter(ast->lhs, &new);
if (new) {
s->u.nt = newNonTerminal(s->name);
s->tag = NONTERMINAL;
} else {
if (s->tag != NONTERMINAL) {
fprintf(stderr, "Illegal use of %s as a non-terminal\n", s->name);
exit(1);
}
}
ZEROCOST(delta);
for (p = ast->cost, i = 0; p; p = p->next, i++) {
int x = p->x;
#ifndef NOLEX
if (lexical) {
if (i < DELTAWIDTH) {
delta[i] = x;
}
} else
#endif /* NOLEX */
{
if (i == principleCost) {
PRINCIPLECOST(delta) = x;
}
}
}
ast->rule = newRule(delta, ast->erulenum, s->u.nt, 0);
}
static void
doRule(ast) RuleAST ast;
{
Pattern pat;
(void) normalize(ast->pat, ast->rule->lhs, &pat);
ast->rule->pat = pat;
}
static void
doTable(op) Operator op;
{
op->table = newTable(op);
}
void
doSpec(decls, rules) List decls; List rules;
{
foreachList((ListFn) doDecl, decls);
debug(debugTables, foreachList((ListFn) dumpOperator_l, operators));
ruleASTs = rules;
reveachList((ListFn) doEnterNonTerm, rules);
last_user_nonterminal = max_nonterminal;
reveachList((ListFn) doRule, rules);
debug(debugTables, foreachList((ListFn) dumpRule, rules));
foreachList((ListFn) doTable, operators);
}
void
doStart(name) char *name;
{
Symbol s;
int new;
if (start) {
yyerror1("Redeclaration of start symbol to be ");
fprintf(stderr, "\"%s\"\n", name);
exit(1);
}
s = enter(name, &new);
if (new) {
s->u.nt = newNonTerminal(s->name);
s->tag = NONTERMINAL;
} else {
if (s->tag != NONTERMINAL) {
fprintf(stderr, "Illegal use of %s as a non-terminal\n", s->name);
exit(1);
}
}
}
Arity
newArity(ar, b) int ar; List b;
{
Arity a = (Arity) zalloc(sizeof(struct arity));
a->arity = ar;
a->bindings = b;
return a;
}
Binding
newBinding(name, opnum) char *name; int opnum;
{
Binding b = (Binding) zalloc(sizeof(struct binding));
if (opnum == 0) {
yyerror1("ERROR: Non-positive external symbol number, ");
fprintf(stderr, "%d", opnum);
exit(1);
}
b->name = name;
b->opnum = opnum;
return b;
}
PatternAST
newPatternAST(op, children) char *op; List children;
{
PatternAST p = (PatternAST) zalloc(sizeof(struct patternAST));
p->op = op;
p->children = children;
return p;
}
int max_ruleAST;
RuleAST
newRuleAST(lhs, pat, erulenum, cost) char *lhs; PatternAST pat; int erulenum; IntList cost;
{
RuleAST p = (RuleAST) zalloc(sizeof(struct ruleAST));
p->lhs = lhs;
p->pat = pat;
if (erulenum <= 0) {
yyerror1("External Rulenumber ");
fprintf(stderr, "(%d) <= 0\n", erulenum);
exit(1);
}
p->erulenum = erulenum;
p->cost = cost;
max_ruleAST++;
return p;
}
void
dumpBinding(b) Binding b;
{
printf("%s=%d ", b->name, b->opnum);
}
void
dumpArity(a) Arity a;
{
List l;
printf("Arity(%d) ", a->arity);
for (l = a->bindings; l; l = l->next) {
Binding b = (Binding) l->x;
dumpBinding(b);
}
printf("\n");
}
void
dumpPatternAST(p) PatternAST p;
{
List l;
printf("%s", p->op);
if (p->children) {
printf("(");
for (l = p->children; l; l = l->next) {
PatternAST past = (PatternAST) l->x;
dumpPatternAST(past);
if (l->next) {
printf(", ");
}
}
printf(")");
}
}
void
dumpRuleAST(p) RuleAST p;
{
printf("%s : ", p->lhs);
dumpPatternAST(p->pat);
printf(" = %d (%ld)\n", p->erulenum, (long) p->cost);
}
void
dumpDecls(decls) List decls;
{
List l;
for (l = decls; l; l = l->next) {
Arity a = (Arity) l->x;
dumpArity(a);
}
}
void
dumpRules(rules) List rules;
{
List l;
for (l = rules; l; l = l->next) {
RuleAST p = (RuleAST) l->x;
dumpRuleAST(p);
}
}