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2022-09-29 17:59:04 +03:00

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C

/* Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. */
/* Copyright (c) 1988 AT&T */
/* All Rights Reserved */
/* THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF */
/* UNIX System Laboratories, Inc. */
/* The copyright notice above does not evidence any */
/* actual or intended publication of such source code. */
#ident "$Header: /proj/irix6.5.7m/isms/eoe/cmd/yacc/RCS/y3.c,v 1.7 1996/03/19 23:39:39 danc Exp $"
# include "dextern"
static void go2gen(int c);
static void precftn(int r, int t, int s);
static void wract(int i);
static void wrstate(int i);
static void wdef(char *s, int n);
/* important local variables */
static int lastred; /* number of the last reduction of a state */
int *defact;
extern int *toklev;
extern int cwp;
/* Emit #defines for the external symbols like yyerror, so that they are
either prefixed by 'yy', or with <sym_prefix> if -p <sym_prefix> was
specified on the yacc command line */
void
output_prefix(void)
{
if (symbol_prefix != NULL) {
fprintf(ftable, "#define yyparse %sparse\n", symbol_prefix);
fprintf(ftable, "#define yylval %slval\n", symbol_prefix);
fprintf(ftable, "#define yyval %sval\n", symbol_prefix);
fprintf(ftable, "#define yy_yys %s_yys\n", symbol_prefix);
fprintf(ftable, "#define yys %ss\n", symbol_prefix);
fprintf(ftable, "#define yy_yyv %s_yyv\n", symbol_prefix);
fprintf(ftable, "#define yyv %sv\n", symbol_prefix);
fprintf(ftable, "#define yyexca %sexca\n", symbol_prefix);
fprintf(ftable, "#define yyact %sact\n", symbol_prefix);
fprintf(ftable, "#define yypact %spact\n", symbol_prefix);
fprintf(ftable, "#define yypgo %spgo\n", symbol_prefix);
fprintf(ftable, "#define yyr1 %sr1\n", symbol_prefix);
fprintf(ftable, "#define yyr2 %sr2\n", symbol_prefix);
fprintf(ftable, "#define yychk %schk\n", symbol_prefix);
fprintf(ftable, "#define yydef %sdef\n", symbol_prefix);
fprintf(ftable, "#define yytoks %stoks\n", symbol_prefix);
fprintf(ftable, "#define yyreds %sreds\n", symbol_prefix);
fprintf(ftable, "#define yydebug %sdebug\n", symbol_prefix);
fprintf(ftable, "#define yypv %spv\n", symbol_prefix);
fprintf(ftable, "#define yyps %sps\n", symbol_prefix);
fprintf(ftable, "#define yystate %sstate\n", symbol_prefix);
fprintf(ftable, "#define yytmp %stmp\n", symbol_prefix);
fprintf(ftable, "#define yynerrs %snerrs\n", symbol_prefix);
fprintf(ftable, "#define yyerrflag %serrflag\n", symbol_prefix);
fprintf(ftable, "#define yychar %schar\n", symbol_prefix);
fprintf(ftable, "#define yyerror %serror\n", symbol_prefix);
fprintf(ftable, "#define yylex %slex\n", symbol_prefix);
} /* if */
} /* output_prefix */
/* print the output for the states */
void
output(void)
{
int i, k, c;
register WSET *u, *v;
(void) fprintf( ftable, "yytabelem yyexca[] ={\n" );
SLOOP(i) { /* output the stuff for state i */
nolook = !(tystate[i]==MUSTLOOKAHEAD);
closure(i);
/* output actions */
nolook = 1;
aryfil(temp1, ntoksz+nnontersz+1, 0);
WSLOOP(wsets,u) {
c = *(u->pitem);
if (c>1 && c<NTBASE && temp1[c]==0) {
WSLOOP(u,v) {
if (c == *(v->pitem))
putitem(v->pitem+1, (LOOKSETS *)0);
}
temp1[c] = state(c);
}
else if (c > NTBASE && temp1[(c -= NTBASE)+ntokens]==0){
temp1[ c+ntokens ] = amem[indgo[i]+c];
}
}
if (i == 1)
temp1[1] = ACCEPTCODE;
/* now, we have the shifts; look at the reductions */
lastred = 0;
WSLOOP(wsets,u) {
c = *(u->pitem);
if (c<=0) { /* reduction */
lastred = -c;
TLOOP(k) {
if (BIT(u->ws.lset,k)) {
if (temp1[k] == 0)
temp1[k] = c;
else if (temp1[k]<0) { /* reduce/reduce conflict */
if (foutput!=NULL)
(void) pfmt(foutput,
MM_NOSTD, ":92:\n%d: reduce/reduce conflict (red'ns %d and %d ) on %s",
i, -temp1[k], lastred, symnam(k) );
if( -temp1[k] > lastred ) temp1[k] = -lastred;
++zzrrconf;
}
else /* potential shift/reduce conflict */
precftn( lastred, k, i );
}
}
}
}
wract(i);
}
(void) fprintf(ftable, "\t};\n");
wdef("YYNPROD", nprod);
}
static int pkdebug = 0;
int
apack(int *p, int n)
{
/* pack state i from temp1 into amem */
int off;
register int *pp, *qq;
int *q, *r, *rr;
/* we don't need to worry about checking because we
we will only look up entries known to be there... */
/* eliminate leading and trailing 0's */
q = p+n;
for( pp=p,off=0 ; *pp==0 && pp<=q; ++pp,--off ) /* EMPTY */ ;
if( pp > q ) return(0); /* no actions */
p = pp;
/* now, find a place for the elements from p to q, inclusive */
/* for( rr=amem; rr<=r; ++rr,++off ){ */ /* try rr */
rr = amem;
for ( ; ; ++rr, ++off) {
if (rr >= &amem[new_actsize-1])
exp_act(&rr);
qq=rr;
for( pp=p ; pp<=q ; ++pp,++qq){
if( *pp ){
if ( qq >= &amem[new_actsize-1]) {
r=rr;
exp_act(&rr);
qq = qq - r + rr;
}
if( *pp != *qq && *qq != 0 ) goto nextk;
}
}
/* we have found an acceptable k */
if( pkdebug && foutput!=NULL )
(void) fprintf( foutput, "off = %d, k = %d\n", off, rr-amem );
qq=rr;
for( pp=p; pp<=q; ++pp,++qq ){
if( *pp ){
if( qq >= &amem[new_actsize-1] ) {
r=rr;
exp_act(&rr);
qq = qq - r + rr;
}
if( qq>memp ) memp = qq;
*qq = *pp;
}
}
if( pkdebug && foutput!=NULL ){
for( pp=amem; pp<= memp; pp+=10 ){
(void) fprintf( foutput, "\t");
for( qq=pp; qq<=pp+9; ++qq )
(void) fprintf( foutput, "%d ", *qq );
(void) fprintf( foutput, "\n");
}
}
return( off );
nextk: ;
}
/* error("no space in action table" ); */
/* NOTREACHED */
}
void
go2out(void)
{
/* output the gotos for the nontermninals */
int i, j, k, best, count, cbest, times;
(void) fprintf( ftemp, "$\n" ); /* mark begining of gotos */
for( i=1; i<=nnonter; ++i ) {
go2gen(i);
/* find the best one to make default */
best = -1;
times = 0;
for( j=0; j<=nstate; ++j ){ /* is j the most frequent */
if( tystate[j] == 0 ) continue;
if( tystate[j] == best ) continue;
/* is tystate[j] the most frequent */
count = 0;
cbest = tystate[j];
for( k=j; k<=nstate; ++k ) if( tystate[k]==cbest ) ++count;
if( count > times ){
best = cbest;
times = count;
}
}
/* best is now the default entry */
zzgobest += (times-1);
for( j=0; j<=nstate; ++j ){
if( tystate[j] != 0 && tystate[j]!=best ){
(void) fprintf( ftemp, "%d,%d,", j, tystate[j] );
zzgoent += 1;
}
}
/* now, the default */
zzgoent += 1;
(void) fprintf( ftemp, "%d\n", best );
}
}
static int g2debug = 0;
static void
go2gen(int c)
{
/* output the gotos for nonterminal c */
int i, work, cc;
ITEM *p, *q;
/* first, find nonterminals with gotos on c */
aryfil( temp1, nnonter+1, 0 );
temp1[c] = 1;
work = 1;
while( work ){
work = 0;
PLOOP(0,i){
if( (cc=prdptr[i][1]-NTBASE) >= 0 ){ /* cc is a nonterminal */
if( temp1[cc] != 0 ){ /* cc has a goto on c */
cc = *prdptr[i]-NTBASE; /* thus, the left side of production i does too */
if( temp1[cc] == 0 ){
work = 1;
temp1[cc] = 1;
}
}
}
}
}
/* now, we have temp1[c] = 1 if a goto on c in closure of cc */
if( g2debug && foutput!=NULL ){
(void) fprintf( foutput, "%s: gotos on ", nontrst[c].name );
NTLOOP(i) if( temp1[i] ) (void) fprintf( foutput, "%s ", nontrst[i].name);
(void) fprintf( foutput, "\n");
}
/* now, go through and put gotos into tystate */
aryfil( tystate, nstate, 0 );
SLOOP(i){
ITMLOOP(i,p,q){
if( (cc= *p->pitem) >= NTBASE ){
if( temp1[cc -= NTBASE] ){ /* goto on c is possible */
tystate[i] = amem[indgo[i]+c];
break;
}
}
}
}
}
static void
precftn(int r, int t, int s)
{
/* decide a shift/reduce conflict by precedence.
* r is a rule number, t a token number
* the conflict is in state s
* temp1[t] is changed to reflect the action
*/
int lp,lt, action;
lp = levprd[r];
lt = toklev[t];
if( PLEVEL(lt) == 0 || PLEVEL(lp) == 0 ) {
/* conflict */
if( foutput != NULL ) (void) pfmt( foutput, MM_NOSTD, ":93:\n%d: shift/reduce conflict (shift %d, red'n %d) on %s",
s, temp1[t], r, symnam(t) );
++zzsrconf;
return;
}
if( PLEVEL(lt) == PLEVEL(lp) ) action = ASSOC(lt) & ~04;
else if( PLEVEL(lt) > PLEVEL(lp) ) action = RASC; /* shift */
else action = LASC; /* reduce */
switch( action ){
case BASC: /* error action */
temp1[t] = ERRCODE;
return;
case LASC: /* reduce */
temp1[t] = -r;
return;
}
}
static void
wract(int i) /* output state i */
{
/* temp1 has the actions, lastred the default */
int p, p0, p1;
int ntimes, tred, count, j;
int flag;
/* find the best choice for lastred */
lastred = 0;
ntimes = 0;
TLOOP(j){
if( temp1[j] >= 0 ) continue;
if( temp1[j]+lastred == 0 ) continue;
/* count the number of appearances of temp1[j] */
count = 0;
tred = -temp1[j];
SETRED(levprd[tred], 1);
TLOOP(p){
if( temp1[p]+tred == 0 ) ++count;
}
if( count >ntimes ){
lastred = tred;
ntimes = count;
}
}
/* for error recovery, arrange that, if there is a shift on the
* error recovery token, `error', that the default be the error
* action
*/
if( temp1[2] > 0 ) lastred = 0;
/* clear out entries in temp1 which equal lastred */
TLOOP(p) if( temp1[p]+lastred == 0 )temp1[p]=0;
wrstate(i);
defact[i] = lastred;
flag = 0;
TLOOP(p0){
if( (p1=temp1[p0])!=0 ) {
if( p1 < 0 ){
p1 = -p1;
goto exc;
}
else if( p1 == ACCEPTCODE ) {
p1 = -1;
goto exc;
}
else if( p1 == ERRCODE ) {
p1 = 0;
goto exc;
exc:
if( flag++ == 0 ) (void) fprintf( ftable, "-1, %d,\n", i );
(void) fprintf( ftable, "\t%d, %d,\n", tokset[p0].value, p1 );
++zzexcp;
}
else {
(void) fprintf( ftemp, "%d,%d,", tokset[p0].value, p1 );
++zzacent;
}
}
}
if( flag ) {
defact[i] = -2;
(void) fprintf( ftable, "\t-2, %d,\n", lastred );
}
(void) fprintf( ftemp, "\n" );
return;
}
static void
wrstate(int i) /* writes state i */
{
register int j0,j1;
register ITEM *pp, *qq;
register WSET *u;
if( foutput == NULL ) return;
(void) fprintf( foutput, "\nstate %d\n",i);
ITMLOOP(i,pp,qq) (void) fprintf( foutput, "\t%s\n", writem(pp->pitem));
if( tystate[i] == MUSTLOOKAHEAD ){
/* print out empty productions in closure */
WSLOOP( wsets+(pstate[i+1]-pstate[i]), u ){
if( *(u->pitem) < 0 ) (void) fprintf( foutput, "\t%s\n", writem(u->pitem) );
}
}
/* check for state equal to another */
TLOOP(j0) if( (j1=temp1[j0]) != 0 ){
(void) fprintf( foutput, "\n\t%s ", symnam(j0) );
if( j1>0 ){ /* shift, error, or accept */
if( j1 == ACCEPTCODE ) (void) pfmt( foutput, MM_NOSTD, ":94:accept" );
else if( j1 == ERRCODE ) (void) pfmt( foutput, MM_NOSTD, ":95:error" );
else (void) pfmt( foutput, MM_NOSTD, ":96:shift %d", j1 );
}
else (void) pfmt( foutput, MM_NOSTD, ":97:reduce %d",-j1 );
}
/* output the final production */
if( lastred ) (void) pfmt( foutput, MM_NOSTD, ":98:\n\t. reduce %d\n\n", lastred );
else (void) pfmt( foutput, MM_NOSTD, ":99:\n\t. error\n\n" );
/* now, output nonterminal actions */
j1 = ntokens;
for( j0 = 1; j0 <= nnonter; ++j0 ){
if( temp1[++j1] ) (void) pfmt( foutput, MM_NOSTD, ":100:\t%s goto %d\n", symnam( j0+NTBASE), temp1[j1] );
}
}
static void
wdef(char *s, int n) /* output a definition of s to the value n */
{
(void) fprintf( ftable, "# define %s %d\n", s, n );
}
void
warray(char *s, int *v, int n)
{
register int i;
(void) fprintf( ftable, "yytabelem %s[]={\n", s );
for( i=0; i<n; ){
if( i%10 == 0 ) (void) fprintf( ftable, "\n" );
(void) fprintf( ftable, "%6d", v[i] );
if( ++i == n ) (void) fprintf( ftable, " };\n" );
else (void) fprintf( ftable, "," );
}
}
void
hideprod(void)
{
/* in order to free up the mem and amem arrays for the optimizer,
* and still be able to output yyr1, etc., after the sizes of
* the action array is known, we hide the nonterminals
* derived by productions in levprd.
*/
register int i, j;
j = 0;
levprd[0] = 0;
PLOOP(1,i){
if( !(REDBIT(levprd[i])) ){
++j;
if( foutput != NULL ){
(void) pfmt( foutput, MM_NOSTD, ":101:Rule not reduced: %s\n", writem( prdptr[i] ) );
}
}
levprd[i] = *prdptr[i] - NTBASE;
}
if( j ) (void) pfmt( stderr, MM_ERROR, ":102:%d rules never reduced\n", j );
}