377 lines
7.4 KiB
Plaintext
377 lines
7.4 KiB
Plaintext
/*
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* Some grammar independent code.
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* This file is copied into Lpars.c.
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*/
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#ifndef lint
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static char *rcsid = "$Id$";
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#endif
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unsigned int LLtcnt[LL_NTERMINALS];
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unsigned int LLscnt[LL_NSETS];
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int LLcsymb, LLsymb;
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static int LLlevel;
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#if LL_NON_CORR
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int LLstartsymb;
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static int fake_eof = 0;
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#endif
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#define LL_VOIDCST (void)
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void LLmessage(int);
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#ifdef LL_USERHOOK
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static int LLdoskip(int);
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static int LLuserhook(int, int*);
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#endif
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#ifndef LL_FASTER
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void LLscan(int t)
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{
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/*
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* Check if the next symbol is equal to the parameter
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*/
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#if LL_NON_CORR
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/* See if the error recovery has eaten an eof */
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if (fake_eof) {
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LLsymb = EOFILE;
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fake_eof = 0;
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}
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else {
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LLsymb = LL_LEXI();
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}
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if (LLsymb == t) {
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#else
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if ((LLsymb = LL_LEXI()) == t) {
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#endif
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#if LL_NON_CORR
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/* Check if a previous parser has 'crashed', in that
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* case continue with non-correcting parser
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*/
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if (err_seen && !nc_done) {
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LLnc_recover();
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nc_done = 1;
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/* Remember that the error recovery has eaten an eof */
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fake_eof = 1;
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if (t != LLsymb) {
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LLerror(t);
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}
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else
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return;
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}
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#endif
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return;
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}
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/*
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* If we come here, an error has been detected
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*/
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LLerror(t);
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}
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#endif
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void LLread(void) {
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#if LL_NON_CORR
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/* Again, check if another parser has crashed,
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* in that case intercept and go to the
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* non-correcting parser
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*/
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if (err_seen && !nc_done) {
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LLnc_recover();
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nc_done = 1;
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/* Pretend we read end of file */
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LLsymb = EOFILE;
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LLcsymb = LLindex[EOFILE];
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fake_eof = 0;
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return;
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}
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if (fake_eof) {
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LLsymb = EOFILE;
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LLcsymb = LLindex[EOFILE];
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fake_eof = 0;
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return;
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}
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#endif
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for (;;) {
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if ((LLcsymb = LLindex[(LLsymb = LL_LEXI())]) >= 0) return;
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LLmessage(0);
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}
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/* NOTREACHED */
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}
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void LLerror(int t)
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{
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register int i;
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if (t == EOFILE && LLsymb <= 0) return;
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#ifdef LL_NEWMESS
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if (t == EOFILE) {
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#ifdef LL_USERHOOK
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static int lst[] = { EOFILE, 0 };
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LL_VOIDCST LLuserhook(EOFILE, lst);
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#endif /* LL_USERHOOK */
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if (LLsymb != EOFILE && LLsymb > 0) {
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LLmessage(-1);
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while ((LLsymb = LL_LEXI()) > 0 && LLsymb != EOFILE)
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/* nothing */ ;
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}
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return;
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}
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#endif
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#if LL_NON_CORR
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if ((!nc_done) && (LLsymb > 0) && (LLsymb != EOFILE)) {
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LLmessage(0);
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LLnc_recover();
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nc_done = 1;
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LLsymb = EOFILE;
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}
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#endif
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if ((LLcsymb = LLindex[LLsymb]) < 0) {
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LLmessage(0);
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LLread();
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}
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i = LLindex[t];
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LLtcnt[i]++;
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#ifdef LL_USERHOOK
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LL_VOIDCST LLdoskip(t);
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#else
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LL_VOIDCST LLskip();
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#endif
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LLtcnt[i]--;
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if (LLsymb != t) {
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#if LL_NON_CORR
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/* A little kludge here; when using non-correcting recovery
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* it can happen that a program is correct but incomplete.
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* Here, we test this, and make sure the appropriate
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* message is generated
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*/
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if (! nc_done) {
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int oldLLsymb;
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oldLLsymb = LLsymb;
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LLsymb = EOFILE;
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LLmessage(0);
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nc_done = 1;
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/* Not really, but to prevent more than 1 error message */
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LLsymb = oldLLsymb;
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}
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#endif
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LLmessage(t);
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}
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}
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void LLsafeerror(int t)
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{
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if (t == EOFILE && LLsymb <= 0) return;
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#ifdef LL_NEWMESS
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if (t == EOFILE) {
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#ifdef LL_USERHOOK
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static int lst[] = { EOFILE, 0 };
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LL_VOIDCST LLuserhook(EOFILE, lst);
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#endif /* LL_USERHOOK */
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if (LLsymb != EOFILE && LLsymb > 0) {
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LLmessage(-1);
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while ((LLsymb = LL_LEXI()) > 0 && LLsymb != EOFILE)
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/* nothing */ ;
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}
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return;
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}
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#endif
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#if LL_NON_CORR
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if ((!nc_done) && (LLsymb > 0) && (LLsymb != EOFILE)) {
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LLmessage(0);
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LLnc_recover();
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nc_done = 1;
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LLsymb = EOFILE;
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}
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/* A little kludge here; when using non-correcting recovery
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* it can happen that a program is correct but incomplete.
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* Here, we test this, and make sure the appropriate
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* message is generated
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*/
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if (! nc_done) {
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int oldLLsymb;
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oldLLsymb = LLsymb;
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LLsymb = EOFILE;
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LLmessage(0);
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nc_done = 1;
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/* Not really, but to prevent more than 1 error message */
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LLsymb = oldLLsymb;
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}
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#endif
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LLmessage(t);
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}
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#ifndef LLNOFIRSTS
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int LLfirst(int x, int d) {
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register int i;
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return (i = LLindex[x]) >= 0 &&
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(LLsets[d + (i >> 3)] & (1 << (i & 07)));
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}
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#endif
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int LLnext(int n)
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{
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/* returns: 0 if the current symbol is'nt skipped, and it
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is'nt a member of "n",
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1 if we have a new symbol, but it is'nt a member,
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2 if the current symbol is a member,
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and 3 if we have a new symbol and it is a member.
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So, the low order bit indicates wether we have a new symbol,
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and the next bit indicates wether it is a member of "n".
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*/
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int retval = 0;
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if (LLskip()) retval = 1;
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if (n <= 0 && LLsets[(LLcsymb >> 3) - n] & (1 << (LLcsymb & 07))) {
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retval |= 2;
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}
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else if (n > 0 && LLcsymb == LLindex[n]) retval |= 2;
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return retval;
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}
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int LLskip(void) {
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/* returns 0 if the current symbol is'nt skipped, and
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1 if it is, t.i., we have a new symbol
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*/
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#ifdef LL_USERHOOK
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return LLdoskip(0);
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}
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extern void LL_USERHOOK(int, int *);
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static int LLuserhook(int e, int *list)
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{
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int old = LLsymb;
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LL_USERHOOK(e, list);
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LLread();
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return LLsymb != old;
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}
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static void LLmklist(register int *list)
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{
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char Xset[LL_SSIZE];
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register char *p;
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register int i;
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for (p = &Xset[0]; p < &Xset[LL_SSIZE]; ) *p++ = 0;
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for (i = 0; i < LL_NTERMINALS; i++) {
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if (LLtcnt[i] != 0) Xset[i >> 3] |= (1 << (i & 07));
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}
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for (i = LL_NSETS - 1; i >= 0; i--) if (LLscnt[i] != 0) {
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register char *q = &LLsets[LL_SSIZE * i];
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p = &Xset[0];
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while (p < &Xset[LL_SSIZE]) *p++ |= *q++;
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}
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for (i = 0; i < LL_NTERMINALS; i++) {
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if (Xset[i >> 3] & (1 << (i & 07))) {
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*list++ = LLtok[i];
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}
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}
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*list = 0;
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}
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static int LLdoskip(int e)
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{
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int LLx;
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int list[LL_NTERMINALS+1];
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#endif /* LL_USERHOOK */
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register int i;
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int retval;
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int LLi, LLb;
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retval = 0;
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#ifdef LL_USERHOOK
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LLmklist(list);
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LLx = LLuserhook(e, list);
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if (LLx) retval = 1;
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#endif /* LL_USERHOOK */
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for (;;) {
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if (LLtcnt[LLcsymb] != 0) {
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#ifdef LL_USERHOOK
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if (!e || !LLx || LLcsymb == LLindex[e])
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#endif
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return retval;
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}
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LLi = LLcsymb >> 3;
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LLb = 1 << (LLcsymb & 07);
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for (i = LL_NSETS - 1; i >= 0; i--) {
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if (LLscnt[i] != 0) {
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if (LLsets[LL_SSIZE*i+LLi] & LLb) {
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#ifdef LL_USERHOOK
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if (!e || !LLx || LLcsymb == LLindex[e])
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#endif
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return retval;
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}
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}
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}
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#ifdef LL_USERHOOK
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if (LLx) {
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LLx = LLuserhook(e, list);
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continue;
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}
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#endif /* LL_USERHOOK */
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#if LL_NON_CORR
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if ((!nc_done) && (LLsymb > 0)) {
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LLmessage(0);
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LLnc_recover();
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nc_done = 1;
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fake_eof = 1;
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}
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else {
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LLmessage(0);
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}
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#else
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LLmessage(0);
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#endif
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retval = 1;
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LLread();
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}
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/* NOTREACHED */
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}
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void LLnewlevel(unsigned int *LLsinfo) {
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register int i;
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if (LLlevel++) {
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LLsinfo[LL_NSETS+LL_NTERMINALS] = (unsigned) LLsymb;
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LLsinfo[LL_NSETS+LL_NTERMINALS+1] = (unsigned) LLcsymb;
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for (i = LL_NTERMINALS - 1; i >= 0; i--) {
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LLsinfo[i] = LLtcnt[i];
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LLtcnt[i] = 0;
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}
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for (i = LL_NSETS - 1; i >= 0; i--) {
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LLsinfo[LL_NTERMINALS+i] = LLscnt[i];
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LLscnt[i] = 0;
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}
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}
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LLtincr(0);
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}
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void LLoldlevel(unsigned int *LLsinfo) {
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register int i;
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LLtdecr(0);
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#ifdef LL_DEBUG
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for (i = 0; i < LL_NTERMINALS; i++) LL_assert(LLtcnt[i] == 0);
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for (i = 0; i < LL_NSETS; i++) LL_assert(LLscnt[i] == 0);
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#endif
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if (--LLlevel) {
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for (i = LL_NSETS - 1; i >= 0; i--) {
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LLscnt[i] = LLsinfo[LL_NTERMINALS+i];
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}
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for (i = LL_NTERMINALS - 1; i >= 0; i--) {
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LLtcnt[i] = LLsinfo[i];
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}
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LLsymb = (int) LLsinfo[LL_NSETS+LL_NTERMINALS];
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LLcsymb = (int) LLsinfo[LL_NSETS+LL_NTERMINALS+1];
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}
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}
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