New version, much faster

This commit is contained in:
ceriel 1985-11-25 15:50:19 +00:00
parent 42d0e056fb
commit 70a5d416d1

View file

@ -3,215 +3,149 @@
* This file is copied into Lpars.c.
*/
# ifndef NORCSID
# ifndef lint
static char *rcsid = "$Header$";
# endif
#define LLSTSIZ 1024
static short LLstack[LLSTSIZ]; /* Recovery stack */
short * LLptr; /* ptr in it */
#define LLmax (&LLstack[LLSTSIZ-1]) /* if beyond this, overflow */
int LLscd; /* lookahead done or not? */
int LLb,LLi;
int LLsymb;
int LLcsymb;
static int LLlevel;
static short * LLbase;
# ifdef LL_DEBUG
# include <stdio.h>
# endif
static struct LLsaved {
int LLs_i, LLs_b, LLs_s, LLs_c, LLs_t;
short *LLs_p, *LLs_x;
} LLsaved[LL_MAX];
int LLsymb;
unsigned int LLtcnt[LL_NTERMINALS];
unsigned int LLscnt[LL_NSETS];
int LLcsymb, LLsymb;
static int LLlevel;
/* In this file are defined: */
extern LLcheck();
extern LLread();
extern int LLskip();
extern int LLnext();
extern LLscan();
extern LLpush();
extern LLlpush();
extern int LLpop();
extern int LLsskip();
static LLerror();
extern LLerror();
# ifndef LLNOFIRSTS
extern int LLfirst();
# endif
extern LLnewlevel();
extern LLoldlevel();
LLcheck() {
register c;
/*
* The symbol to be checked is on the stack.
*/
if (!LLscd) {
if ((c = LL_LEXI()) <= 0) c = EOFILE;
LLsymb = c;
}
else LLscd = 0;
if (LLsymb == *--LLptr) return;
/*
* If we come here, an error has been detected.
* LLpop will try and recover
*/
LLptr++;
while (LLindex[LLsymb] < 0) {
LLerror(0);
if ((LLsymb = LL_LEXI()) <= 0) LLsymb = EOFILE;
}
LLcsymb = LLindex[LLsymb];
LLb = LLbyte[LLcsymb];
LLi = LLcsymb>>3;
LLscd = 1;
if (!LLpop()) LLerror(*LLptr);
LLscd = 0;
}
LLscan(t) {
/*
* Check if the next symbol is equal to the parameter
*/
if (!LLscd) {
if ((LLsymb = LL_LEXI()) <= 0) LLsymb = EOFILE;
if ((LLsymb = LL_LEXI()) <= 0) LLsymb = EOFILE;
if (LLsymb == t) {
return;
}
else LLscd = 0;
if (LLsymb == t) return;
/*
* If we come here, an error has been detected
*/
LLpush(t);
LLscd = 1;
while (LLindex[LLsymb] < 0) {
LLerror(0);
if ((LLsymb = LL_LEXI()) <= 0) LLsymb = EOFILE;
}
LLcsymb = LLindex[LLsymb];
LLb = LLbyte[LLcsymb];
LLi = LLcsymb>>3;
if (!LLpop()) LLerror(t);
LLscd = 0;
LLerror(t);
}
LLpush(t) {
if (LLptr == LLmax) {
LLerror(-1);
}
*LLptr++ = t;
}
LLlpush(d) {
register i;
register short *p;
p = &LLlists[d];
i = *p++;
while(i--) {
if (LLptr == LLmax) {
LLerror(-1);
}
*LLptr++ = *p++;
}
}
LLsskip() {
/*
* Error recovery, and not only that!
* Skip symbols until one is found that is on the stack.
* Return 1 if it is on top of the stack
*/
register short *t;
register i;
LLread() {
for (;;) {
if (!LLscd) {
lab:
if ((i = LL_LEXI()) <= 0) i = EOFILE;
LLsymb = i;
if ((i = LLindex[i]) < 0) {
LLerror(0);
goto lab;
/*
* Ugly, but we want speed
* on possibly correct symbols !!
* So, no breaks out of "for (;;)"
*/
if ((LLsymb = LL_LEXI()) <= 0) LLsymb = EOFILE;
if ((LLcsymb = LLindex[LLsymb]) >= 0) return;
LLmessage(0);
}
/* NOTREACHED */
}
LLerror(t) {
register int i;
if ((LLcsymb = LLindex[LLsymb]) < 0) {
LLmessage(0);
LLread();
}
i = LLindex[t];
LLtcnt[i]++;
if (LLskip()) /* nothing */;
LLtcnt[i]--;
if (LLsymb != t) LLmessage(t);
}
# ifndef LLNOFIRSTS
LLfirst(x, d) {
register int i;
return (i = LLindex[x]) >= 0 &&
(LLsets[d + (i >> 3)] & (1 << (i & 07)));
}
# endif
LLnext(n) {
if (LLskip()) /* nothing */;
if (n <= 0) return (LLsets[(LLcsymb >> 3) - n] & (1 << (LLcsymb & 07)));
return LLsymb == n;
}
LLskip() {
register int i;
int retval;
int LLi, LLb;
retval = 0;
for (;;) {
if (LLtcnt[LLcsymb] != 0) return retval;
LLi = LLcsymb >> 3;
LLb = 1 << (LLcsymb & 07);
for (i = LL_NSETS - 1; i >= 0; i--) {
if (LLscnt[i] != 0) {
if (LLsets[LL_SSIZE*i+LLi] & LLb) return retval;
}
LLcsymb = i;
LLb = LLbyte[i];
LLi = (i>>3);
LLscd = 1;
}
t = LLptr-1;
i = *t;
if (!((i<=0 && LLsets[LLi-i]&LLb)||i==LLsymb)) {
while (--t >= LLbase) {
/*
* If the element on the stack is negative,
* its opposite is an index in the setarray,
* otherwise it is a terminal symbol
*/
i = *t;
if ((i<=0&&LLsets[LLi-i]&LLb)||i==LLsymb){
break;
}
}
if (t >= LLbase) break;
LLerror(0);
LLscd = 0;
retval = 1;
LLmessage(0);
LLread();
}
/* NOTREACHED */
}
LLnewlevel(LLsinfo) unsigned int *LLsinfo; {
register int i;
if (LLlevel++) {
LLsinfo[LL_NSETS+LL_NTERMINALS] = (unsigned) LLsymb;
LLsinfo[LL_NSETS+LL_NTERMINALS+1] = (unsigned) LLcsymb;
for (i = LL_NTERMINALS - 1; i >= 0; i--) {
LLsinfo[i] = LLtcnt[i];
LLtcnt[i] = 0;
}
else {
return 1;
for (i = LL_NSETS - 1; i >= 0; i--) {
LLsinfo[LL_NTERMINALS+i] = LLscnt[i];
LLscnt[i] = 0;
}
}
return t == LLptr - 1;
LLtincr(0);
}
LLpop() {
register i;
LLoldlevel(LLsinfo) unsigned int *LLsinfo; {
register int i;
i = LLsskip();
LLptr--;
return i;
}
static
LLerror(d) {
LLmessage(d);
if (d < 0) exit(1);
}
LLnewlevel() {
register struct LLsaved *p;
if (!LLlevel++) {
LLptr = LLstack;
LLbase = LLstack;
LLpush(EOFILE);
}
else {
if (LLlevel > LL_MAX) LLerror(-1);
p = &LLsaved[LLlevel - 2];
p->LLs_p = LLptr;
p->LLs_i = LLi;
p->LLs_b = LLb;
p->LLs_s = LLsymb;
p->LLs_t = LLcsymb;
p->LLs_c = LLscd;
p->LLs_x = LLbase;
LLbase = LLptr;
LLpush(EOFILE);
}
}
LLoldlevel() {
register struct LLsaved *p;
LLcheck();
LLtdecr(0);
# ifdef LL_DEBUG
for (i = 0; i < LL_NTERMINALS; i++) LL_assert(LLtcnt[i] == 0);
for (i = 0; i < LL_NSETS; i++) LL_assert(LLscnt[i] == 0);
# endif
if (--LLlevel) {
p = &LLsaved[LLlevel-1];
LLptr = p->LLs_p;
LLi = p->LLs_i;
LLb = p->LLs_b;
LLsymb = p->LLs_s;
LLcsymb = p->LLs_t;
LLbase = p->LLs_x;
LLscd = p->LLs_c;
for (i = LL_NSETS - 1; i >= 0; i--) {
LLscnt[i] = LLsinfo[LL_NTERMINALS+i];
}
for (i = LL_NTERMINALS - 1; i >= 0; i--) {
LLtcnt[i] = LLsinfo[i];
}
LLsymb = (int) LLsinfo[LL_NSETS+LL_NTERMINALS];
LLcsymb = (int) LLsinfo[LL_NSETS+LL_NTERMINALS+1];
}
}
# ifdef LL_DEBUG
LL_badassertion(asstr,file,line) char *asstr, *file; {
fprintf(stderr,"Assertion \"%s\" failed %s(%d)\n",asstr,file,line);
abort();
}
# endif