ioef/lcc/lburg/lburg.c
2005-08-26 17:39:27 +00:00

671 lines
18 KiB
C
Executable file

#include <assert.h>
#include <ctype.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include "lburg.h"
static char rcsid[] = "lburg.c - faked rcsid";
static char *prefix = "";
static int Tflag = 0;
static int ntnumber = 0;
static Nonterm start = 0;
static Term terms;
static Nonterm nts;
static Rule rules;
static int nrules;
static struct block {
struct block *link;
} *memlist; /* list of allocated blocks */
static char *stringf(char *fmt, ...);
static void print(char *fmt, ...);
static void ckreach(Nonterm p);
static void emitclosure(Nonterm nts);
static void emitcost(Tree t, char *v);
static void emitdefs(Nonterm nts, int ntnumber);
static void emitheader(void);
static void emitkids(Rule rules, int nrules);
static void emitnts(Rule rules, int nrules);
static void emitrecalc(char *pre, Term root, Term kid);
static void emitrecord(char *pre, Rule r, char *c, int cost);
static void emitrule(Nonterm nts);
static void emitlabel(Term terms, Nonterm start, int ntnumber);
static void emitstring(Rule rules);
static void emitstruct(Nonterm nts, int ntnumber);
static void emittest(Tree t, char *v, char *suffix);
int main(int argc, char *argv[]) {
int c, i;
Nonterm p;
for (i = 1; i < argc; i++)
if (strcmp(argv[i], "-T") == 0)
Tflag = 1;
else if (strncmp(argv[i], "-p", 2) == 0 && argv[i][2])
prefix = &argv[i][2];
else if (strncmp(argv[i], "-p", 2) == 0 && i + 1 < argc)
prefix = argv[++i];
else if (*argv[i] == '-' && argv[i][1]) {
yyerror("usage: %s [-T | -p prefix]... [ [ input ] output ] \n",
argv[0]);
exit(1);
} else if (infp == NULL) {
if (strcmp(argv[i], "-") == 0)
infp = stdin;
else if ((infp = fopen(argv[i], "r")) == NULL) {
yyerror("%s: can't read `%s'\n", argv[0], argv[i]);
exit(1);
}
} else if (outfp == NULL) {
if (strcmp(argv[i], "-") == 0)
outfp = stdout;
if ((outfp = fopen(argv[i], "w")) == NULL) {
yyerror("%s: can't write `%s'\n", argv[0], argv[i]);
exit(1);
}
}
if (infp == NULL)
infp = stdin;
if (outfp == NULL)
outfp = stdout;
yyparse();
if (start)
ckreach(start);
for (p = nts; p; p = p->link) {
if (p->rules == NULL)
yyerror("undefined nonterminal `%s'\n", p->name);
if (!p->reached)
yyerror("can't reach nonterminal `%s'\n", p->name);
}
emitheader();
emitdefs(nts, ntnumber);
emitstruct(nts, ntnumber);
emitnts(rules, nrules);
emitstring(rules);
emitrule(nts);
emitclosure(nts);
if (start)
emitlabel(terms, start, ntnumber);
emitkids(rules, nrules);
if (!feof(infp))
while ((c = getc(infp)) != EOF)
putc(c, outfp);
while (memlist) { /* for purify */
struct block *q = memlist->link;
free(memlist);
memlist = q;
}
return errcnt > 0;
}
/* alloc - allocate nbytes or issue fatal error */
void *alloc(int nbytes) {
struct block *p = calloc(1, sizeof *p + nbytes);
if (p == NULL) {
yyerror("out of memory\n");
exit(1);
}
p->link = memlist;
memlist = p;
return p + 1;
}
/* stringf - format and save a string */
static char *stringf(char *fmt, ...) {
va_list ap;
char buf[512];
va_start(ap, fmt);
vsprintf(buf, fmt, ap);
va_end(ap);
return strcpy(alloc(strlen(buf) + 1), buf);
}
struct entry {
union {
char *name;
struct term t;
struct nonterm nt;
} sym;
struct entry *link;
} *table[211];
#define HASHSIZE (sizeof table/sizeof table[0])
/* hash - return hash number for str */
static unsigned hash(char *str) {
unsigned h = 0;
while (*str)
h = (h<<1) + *str++;
return h;
}
/* lookup - lookup symbol name */
static void *lookup(char *name) {
struct entry *p = table[hash(name)%HASHSIZE];
for ( ; p; p = p->link)
if (strcmp(name, p->sym.name) == 0)
return &p->sym;
return 0;
}
/* install - install symbol name */
static void *install(char *name) {
struct entry *p = alloc(sizeof *p);
int i = hash(name)%HASHSIZE;
p->sym.name = name;
p->link = table[i];
table[i] = p;
return &p->sym;
}
/* nonterm - create a new terminal id, if necessary */
Nonterm nonterm(char *id) {
Nonterm p = lookup(id), *q = &nts;
if (p && p->kind == NONTERM)
return p;
if (p && p->kind == TERM)
yyerror("`%s' is a terminal\n", id);
p = install(id);
p->kind = NONTERM;
p->number = ++ntnumber;
if (p->number == 1)
start = p;
while (*q && (*q)->number < p->number)
q = &(*q)->link;
assert(*q == 0 || (*q)->number != p->number);
p->link = *q;
*q = p;
return p;
}
/* term - create a new terminal id with external symbol number esn */
Term term(char *id, int esn) {
Term p = lookup(id), *q = &terms;
if (p)
yyerror("redefinition of terminal `%s'\n", id);
else
p = install(id);
p->kind = TERM;
p->esn = esn;
p->arity = -1;
while (*q && (*q)->esn < p->esn)
q = &(*q)->link;
if (*q && (*q)->esn == p->esn)
yyerror("duplicate external symbol number `%s=%d'\n",
p->name, p->esn);
p->link = *q;
*q = p;
return p;
}
/* tree - create & initialize a tree node with the given fields */
Tree tree(char *id, Tree left, Tree right) {
Tree t = alloc(sizeof *t);
Term p = lookup(id);
int arity = 0;
if (left && right)
arity = 2;
else if (left)
arity = 1;
if (p == NULL && arity > 0) {
yyerror("undefined terminal `%s'\n", id);
p = term(id, -1);
} else if (p == NULL && arity == 0)
p = (Term)nonterm(id);
else if (p && p->kind == NONTERM && arity > 0) {
yyerror("`%s' is a nonterminal\n", id);
p = term(id, -1);
}
if (p->kind == TERM && p->arity == -1)
p->arity = arity;
if (p->kind == TERM && arity != p->arity)
yyerror("inconsistent arity for terminal `%s'\n", id);
t->op = p;
t->nterms = p->kind == TERM;
if ((t->left = left) != NULL)
t->nterms += left->nterms;
if ((t->right = right) != NULL)
t->nterms += right->nterms;
return t;
}
/* rule - create & initialize a rule with the given fields */
Rule rule(char *id, Tree pattern, char *template, char *code) {
Rule r = alloc(sizeof *r), *q;
Term p = pattern->op;
char *end;
r->lhs = nonterm(id);
r->packed = ++r->lhs->lhscount;
for (q = &r->lhs->rules; *q; q = &(*q)->decode)
;
*q = r;
r->pattern = pattern;
r->ern = ++nrules;
r->template = template;
r->code = code;
r->cost = strtol(code, &end, 10);
if (*end) {
r->cost = -1;
r->code = stringf("(%s)", code);
}
if (p->kind == TERM) {
for (q = &p->rules; *q; q = &(*q)->next)
;
*q = r;
} else if (pattern->left == NULL && pattern->right == NULL) {
Nonterm p = pattern->op;
r->chain = p->chain;
p->chain = r;
if (r->cost == -1)
yyerror("illegal nonconstant cost `%s'\n", code);
}
for (q = &rules; *q; q = &(*q)->link)
;
r->link = *q;
*q = r;
return r;
}
/* print - formatted output */
static void print(char *fmt, ...) {
va_list ap;
va_start(ap, fmt);
for ( ; *fmt; fmt++)
if (*fmt == '%')
switch (*++fmt) {
case 'd': fprintf(outfp, "%d", va_arg(ap, int)); break;
case 's': fputs(va_arg(ap, char *), outfp); break;
case 'P': fprintf(outfp, "%s_", prefix); break;
case 'T': {
Tree t = va_arg(ap, Tree);
print("%S", t->op);
if (t->left && t->right)
print("(%T,%T)", t->left, t->right);
else if (t->left)
print("(%T)", t->left);
break;
}
case 'R': {
Rule r = va_arg(ap, Rule);
print("%S: %T", r->lhs, r->pattern);
break;
}
case 'S': fputs(va_arg(ap, Term)->name, outfp); break;
case '1': case '2': case '3': case '4': case '5': {
int n = *fmt - '0';
while (n-- > 0)
putc('\t', outfp);
break;
}
default: putc(*fmt, outfp); break;
}
else
putc(*fmt, outfp);
va_end(ap);
}
/* reach - mark all nonterminals in tree t as reachable */
static void reach(Tree t) {
Nonterm p = t->op;
if (p->kind == NONTERM)
if (!p->reached)
ckreach(p);
if (t->left)
reach(t->left);
if (t->right)
reach(t->right);
}
/* ckreach - mark all nonterminals reachable from p */
static void ckreach(Nonterm p) {
Rule r;
p->reached = 1;
for (r = p->rules; r; r = r->decode)
reach(r->pattern);
}
/* emitcase - emit one case in function state */
static void emitcase(Term p, int ntnumber) {
Rule r;
print("%1case %d: /* %S */\n", p->esn, p);
switch (p->arity) {
case 0: case -1:
break;
case 1:
print("%2%Plabel(LEFT_CHILD(a));\n");
break;
case 2:
print("%2%Plabel(LEFT_CHILD(a));\n");
print("%2%Plabel(RIGHT_CHILD(a));\n");
break;
default: assert(0);
}
for (r = p->rules; r; r = r->next) {
char *indent = "\t\t\0";
switch (p->arity) {
case 0: case -1:
print("%2/* %R */\n", r);
if (r->cost == -1) {
print("%2c = %s;\n", r->code);
emitrecord("\t\t", r, "c", 0);
} else
emitrecord("\t\t", r, r->code, 0);
break;
case 1:
if (r->pattern->nterms > 1) {
print("%2if (%1/* %R */\n", r);
emittest(r->pattern->left, "LEFT_CHILD(a)", " ");
print("%2) {\n");
indent = "\t\t\t";
} else
print("%2/* %R */\n", r);
if (r->pattern->nterms == 2 && r->pattern->left
&& r->pattern->right == NULL)
emitrecalc(indent, r->pattern->op, r->pattern->left->op);
print("%sc = ", indent);
emitcost(r->pattern->left, "LEFT_CHILD(a)");
print("%s;\n", r->code);
emitrecord(indent, r, "c", 0);
if (indent[2])
print("%2}\n");
break;
case 2:
if (r->pattern->nterms > 1) {
print("%2if (%1/* %R */\n", r);
emittest(r->pattern->left, "LEFT_CHILD(a)",
r->pattern->right->nterms ? " && " : " ");
emittest(r->pattern->right, "RIGHT_CHILD(a)", " ");
print("%2) {\n");
indent = "\t\t\t";
} else
print("%2/* %R */\n", r);
print("%sc = ", indent);
emitcost(r->pattern->left, "LEFT_CHILD(a)");
emitcost(r->pattern->right, "RIGHT_CHILD(a)");
print("%s;\n", r->code);
emitrecord(indent, r, "c", 0);
if (indent[2])
print("%2}\n");
break;
default: assert(0);
}
}
print("%2break;\n");
}
/* emitclosure - emit the closure functions */
static void emitclosure(Nonterm nts) {
Nonterm p;
for (p = nts; p; p = p->link)
if (p->chain)
print("static void %Pclosure_%S(NODEPTR_TYPE, int);\n", p);
print("\n");
for (p = nts; p; p = p->link)
if (p->chain) {
Rule r;
print("static void %Pclosure_%S(NODEPTR_TYPE a, int c) {\n"
"%1struct %Pstate *p = STATE_LABEL(a);\n", p);
for (r = p->chain; r; r = r->chain)
emitrecord("\t", r, "c", r->cost);
print("}\n\n");
}
}
/* emitcost - emit cost computation for tree t */
static void emitcost(Tree t, char *v) {
Nonterm p = t->op;
if (p->kind == TERM) {
if (t->left)
emitcost(t->left, stringf("LEFT_CHILD(%s)", v));
if (t->right)
emitcost(t->right, stringf("RIGHT_CHILD(%s)", v));
} else
print("((struct %Pstate *)(%s->x.state))->cost[%P%S_NT] + ", v, p);
}
/* emitdefs - emit nonterminal defines and data structures */
static void emitdefs(Nonterm nts, int ntnumber) {
Nonterm p;
for (p = nts; p; p = p->link)
print("#define %P%S_NT %d\n", p, p->number);
print("\n");
print("static char *%Pntname[] = {\n%10,\n");
for (p = nts; p; p = p->link)
print("%1\"%S\",\n", p);
print("%10\n};\n\n");
}
/* emitheader - emit initial definitions */
static void emitheader(void) {
time_t timer = time(NULL);
print("/*\ngenerated at %sby %s\n*/\n", ctime(&timer), rcsid);
print("static void %Pkids(NODEPTR_TYPE, int, NODEPTR_TYPE[]);\n");
print("static void %Plabel(NODEPTR_TYPE);\n");
print("static int %Prule(void*, int);\n\n");
}
/* computekids - compute paths to kids in tree t */
static char *computekids(Tree t, char *v, char *bp, int *ip) {
Term p = t->op;
if (p->kind == NONTERM) {
sprintf(bp, "\t\tkids[%d] = %s;\n", (*ip)++, v);
bp += strlen(bp);
} else if (p->arity > 0) {
bp = computekids(t->left, stringf("LEFT_CHILD(%s)", v), bp, ip);
if (p->arity == 2)
bp = computekids(t->right, stringf("RIGHT_CHILD(%s)", v), bp, ip);
}
return bp;
}
/* emitkids - emit _kids */
static void emitkids(Rule rules, int nrules) {
int i;
Rule r, *rc = alloc((nrules + 1 + 1)*sizeof *rc);
char **str = alloc((nrules + 1 + 1)*sizeof *str);
for (i = 0, r = rules; r; r = r->link) {
int j = 0;
char buf[1024], *bp = buf;
*computekids(r->pattern, "p", bp, &j) = 0;
for (j = 0; str[j] && strcmp(str[j], buf); j++)
;
if (str[j] == NULL)
str[j] = strcpy(alloc(strlen(buf) + 1), buf);
r->kids = rc[j];
rc[j] = r;
}
print("static void %Pkids(NODEPTR_TYPE p, int eruleno, NODEPTR_TYPE kids[]) {\n"
"%1if (!p)\n%2fatal(\"%Pkids\", \"Null tree\\n\", 0);\n"
"%1if (!kids)\n%2fatal(\"%Pkids\", \"Null kids\\n\", 0);\n"
"%1switch (eruleno) {\n");
for (i = 0; (r = rc[i]) != NULL; i++) {
for ( ; r; r = r->kids)
print("%1case %d: /* %R */\n", r->ern, r);
print("%s%2break;\n", str[i]);
}
print("%1default:\n%2fatal(\"%Pkids\", \"Bad rule number %%d\\n\", eruleno);\n%1}\n}\n\n");
}
/* emitlabel - emit label function */
static void emitlabel(Term terms, Nonterm start, int ntnumber) {
int i;
Term p;
print("static void %Plabel(NODEPTR_TYPE a) {\n%1int c;\n"
"%1struct %Pstate *p;\n\n"
"%1if (!a)\n%2fatal(\"%Plabel\", \"Null tree\\n\", 0);\n");
print("%1STATE_LABEL(a) = p = allocate(sizeof *p, FUNC);\n"
"%1p->rule._stmt = 0;\n");
for (i = 1; i <= ntnumber; i++)
print("%1p->cost[%d] =\n", i);
print("%20x7fff;\n%1switch (OP_LABEL(a)) {\n");
for (p = terms; p; p = p->link)
emitcase(p, ntnumber);
print("%1default:\n"
"%2fatal(\"%Plabel\", \"Bad terminal %%d\\n\", OP_LABEL(a));\n%1}\n}\n\n");
}
/* computents - fill in bp with _nts vector for tree t */
static char *computents(Tree t, char *bp) {
if (t) {
Nonterm p = t->op;
if (p->kind == NONTERM) {
sprintf(bp, "%s_%s_NT, ", prefix, p->name);
bp += strlen(bp);
} else
bp = computents(t->right, computents(t->left, bp));
}
return bp;
}
/* emitnts - emit _nts ragged array */
static void emitnts(Rule rules, int nrules) {
Rule r;
int i, j, *nts = alloc((nrules + 1)*sizeof *nts);
char **str = alloc((nrules + 1)*sizeof *str);
for (i = 0, r = rules; r; r = r->link) {
char buf[1024];
*computents(r->pattern, buf) = 0;
for (j = 0; str[j] && strcmp(str[j], buf); j++)
;
if (str[j] == NULL) {
print("static short %Pnts_%d[] = { %s0 };\n", j, buf);
str[j] = strcpy(alloc(strlen(buf) + 1), buf);
}
nts[i++] = j;
}
print("\nstatic short *%Pnts[] = {\n");
for (i = j = 0, r = rules; r; r = r->link) {
for ( ; j < r->ern; j++)
print("%10,%1/* %d */\n", j);
print("%1%Pnts_%d,%1/* %d */\n", nts[i++], j++);
}
print("};\n\n");
}
/* emitrecalc - emit code that tests for recalculation of INDIR?(VREGP) */
static void emitrecalc(char *pre, Term root, Term kid) {
if (root->kind == TERM && strncmp(root->name, "INDIR", 5) == 0
&& kid->kind == TERM && strcmp(kid->name, "VREGP" ) == 0) {
Nonterm p;
print("%sif (mayrecalc(a)) {\n", pre);
print("%s%1struct %Pstate *q = a->syms[RX]->u.t.cse->x.state;\n", pre);
for (p = nts; p; p = p->link) {
print("%s%1if (q->cost[%P%S_NT] == 0) {\n", pre, p);
print("%s%2p->cost[%P%S_NT] = 0;\n", pre, p);
print("%s%2p->rule.%P%S = q->rule.%P%S;\n", pre, p, p);
print("%s%1}\n", pre);
}
print("%s}\n", pre);
}
}
/* emitrecord - emit code that tests for a winning match of rule r */
static void emitrecord(char *pre, Rule r, char *c, int cost) {
if (Tflag)
print("%s%Ptrace(a, %d, %s + %d, p->cost[%P%S_NT]);\n",
pre, r->ern, c, cost, r->lhs);
print("%sif (", pre);
print("%s + %d < p->cost[%P%S_NT]) {\n"
"%s%1p->cost[%P%S_NT] = %s + %d;\n%s%1p->rule.%P%S = %d;\n",
c, cost, r->lhs, pre, r->lhs, c, cost, pre, r->lhs,
r->packed);
if (r->lhs->chain)
print("%s%1%Pclosure_%S(a, %s + %d);\n", pre, r->lhs, c, cost);
print("%s}\n", pre);
}
/* emitrule - emit decoding vectors and _rule */
static void emitrule(Nonterm nts) {
Nonterm p;
for (p = nts; p; p = p->link) {
Rule r;
print("static short %Pdecode_%S[] = {\n%10,\n", p);
for (r = p->rules; r; r = r->decode)
print("%1%d,\n", r->ern);
print("};\n\n");
}
print("static int %Prule(void *state, int goalnt) {\n"
"%1if (goalnt < 1 || goalnt > %d)\n%2fatal(\"%Prule\", \"Bad goal nonterminal %%d\\n\", goalnt);\n"
"%1if (!state)\n%2return 0;\n%1switch (goalnt) {\n", ntnumber);
for (p = nts; p; p = p->link)
print("%1case %P%S_NT:"
"%1return %Pdecode_%S[((struct %Pstate *)state)->rule.%P%S];\n", p, p, p);
print("%1default:\n%2fatal(\"%Prule\", \"Bad goal nonterminal %%d\\n\", goalnt);\n%2return 0;\n%1}\n}\n\n");
}
/* emitstring - emit arrays of templates, instruction flags, and rules */
static void emitstring(Rule rules) {
Rule r;
print("static char *%Ptemplates[] = {\n");
print("/* 0 */%10,\n");
for (r = rules; r; r = r->link)
print("/* %d */%1\"%s\",%1/* %R */\n", r->ern, r->template, r);
print("};\n");
print("\nstatic char %Pisinstruction[] = {\n");
print("/* 0 */%10,\n");
for (r = rules; r; r = r->link) {
int len = strlen(r->template);
print("/* %d */%1%d,%1/* %s */\n", r->ern,
len >= 2 && r->template[len-2] == '\\' && r->template[len-1] == 'n',
r->template);
}
print("};\n");
print("\nstatic char *%Pstring[] = {\n");
print("/* 0 */%10,\n");
for (r = rules; r; r = r->link)
print("/* %d */%1\"%R\",\n", r->ern, r);
print("};\n\n");
}
/* emitstruct - emit the definition of the state structure */
static void emitstruct(Nonterm nts, int ntnumber) {
print("struct %Pstate {\n%1short cost[%d];\n%1struct {\n", ntnumber + 1);
for ( ; nts; nts = nts->link) {
int n = 1, m = nts->lhscount;
while ((m >>= 1) != 0)
n++;
print("%2unsigned int %P%S:%d;\n", nts, n);
}
print("%1} rule;\n};\n\n");
}
/* emittest - emit clause for testing a match */
static void emittest(Tree t, char *v, char *suffix) {
Term p = t->op;
if (p->kind == TERM) {
print("%3%s->op == %d%s/* %S */\n", v, p->esn,
t->nterms > 1 ? " && " : suffix, p);
if (t->left)
emittest(t->left, stringf("LEFT_CHILD(%s)", v),
t->right && t->right->nterms ? " && " : suffix);
if (t->right)
emittest(t->right, stringf("RIGHT_CHILD(%s)", v), suffix);
}
}