# 2.11BSD#431 - /usr/src/ucb/pascal/eyacc/ey4.c

##### Functions

    apack             X
    go2               X
    go2gen            X
    go2out            X
    output            X
    precftn           X
    prred             X
    wract             X
    wrstate           X

##### Variables

    cdebug            X
    g2debug           X
    pkdebug           X

       1: /* (c) 1979 Regents of the University of California */
       2: # include "ey.h"
       3:
       4: output(){ /* print the output for the states */
       5:
       6:   int i, j, k, c;
       7:
       8:   settab();
       9:   arrset("yyact");
      10:
      11:   for( i=0; i<nstate; ++i ){ /* output the stuff for state i */
      12:     nolook = (tystate[i]==0);
      13:     closure(i);
      14:     /* output actions */
      15:     aryfil( temp1, nterms+1, 0 );
      16:     for( j=0; j<cwset; ++j ){ /* look at the items */
      17:       c = *( wsets[j].pitem );
      18:       if( c>0 && c<NTBASE && temp1[c]==0 ) temp1[c] = go2(i,c);
      19:       }
      20:
      21:     if( i == 1 ) temp1[1] = ACCEPTCODE;
      22:
      23:     /* now, we have the shifts; look at the reductions */
      24:
      25:     lastred = 0;
      26:     for( j=0; j<cwset; ++j ){
      27:       c = *( wsets[j].pitem );
      28:       if( c<=0 ){ /* reduction */
      29:         lastred = -c;
      30:         for( k=1; k<=nterms; ++k ){
      31:           if( ((wsets[j].ws[k>>4])&(1<<(k&017))) != 0 ) {
      32:             if( temp1[k] == 0 ) temp1[k] = c;
      33:             else if( temp1[k]<0 ){ /* reduce/reduce conflict */
      34:               settty();
      35:               fprintf( cout , "\n%d: reduce/reduce conflict (red'ns %d and %d ) on %s",
      36:                 i, -temp1[k], lastred, symnam(k) );
      37:               if( -temp1[k] > lastred ) temp1[k] = -lastred;
      38:               ++zzrrconf;
      39:               settab();
      40:               }
      41:             else { /* potential shift/reduce conflict */
      42:               switch( precftn( lastred, k ) ) {
      43:
      44:             case 0: /* precedence does not apply */
      45:
      46:                 settty();
      47:                 fprintf( cout , "\n%d: shift/reduce conflict (shift %d, red'n %d) on %s", i,
      48:             temp1[k], lastred, symnam(k) );
      49:                 ++zzsrconf;
      50:                 settab();
      51:                 break;
      52:
      53:             case 1: /*  reduce */
      54:
      55:                 temp1[k] = -lastred;
      56:                 break;
      57:
      58:             case 2: /* error, binary operator */
      59:
      60:                 temp1[k] = ERRCODE;
      61:                 break;
      62:
      63:             case 3: /* shift ... leave the entry alone */
      64:
      65:                 break;
      66:                 }
      67:               }
      68:             }
      69:           }
      70:         }
      71:       }
      72:     wract(i);
      73:     }
      74:
      75:   settab();
      76:   arrdone();
      77:
      78:   /* now, output the pointers to the action array */
      79:   /* also output the info about reductions */
      80:   prred();
      81:   }
      82:
      83: prred(){ /* print the information about the actions and the reductions */
      84:   int index, i;
      85:
      86:   arrset("yypact");
      87:   index = 1;    /* position in the output table */
      88:
      89:   for( i=0; i<nstate; ++i ){
      90:     if( tystate[i]>0 ){  /* the state is real */
      91:       temp1[i] = index;
      92:       arrval( index );
      93:       index += tystate[i];
      94:       }
      95:     else {
      96:       arrval( temp1[-tystate[i]] );
      97:       }
      98:     }
      99:
     100:   arrdone();
     101:
     102:   arrset("yyr1");
     103:   for( i=1; i<nprod; ++i ) arrval( *prdptr[i] - NTBASE );
     104:   arrdone();
     105:
     106:   arrset("yyr2");
     107:   for( i=1; i<nprod; ++i ) arrval( ( prdptr[i+1]-prdptr[i]-2 ) );
     108:   arrdone();
     109:
     110:   }
     111:
     112: go2(i,c){ /* do a goto on the closure state, not worrying about lookaheads */
     113:   if( c<NTBASE ) return( amem[ apstate[i]+c ] );
     114:   else return( amem[ apstate[i] + c - NTBASE + nterms ] );
     115:   }
     116:
     117: int pkdebug = 0;
     118: apack(p, n ) int *p;{ /* pack state i from temp1 into amem */
     119:   _REGISTER k, l, off;
     120:   int j;
     121:
     122:   /* find the spot */
     123:
     124:   j = n;
     125:   for( off = 0; off <= j && p[off] == 0; ++off ) ;
     126:   if( off > j ){ /* no actions */
     127:     return(0);
     128:     }
     129:   j -= off;
     130:   for( k=0; k<actsiz; ++k ){
     131:     for( l=0; l<=j; ++l ){
     132:       if( p[off+l] != 0 ){
     133:         if( p[off+l] != amem[k+l] && amem[k+l] != 0 ) goto nextk;
     134:         }
     135:       }
     136:     if( pkdebug ){ settty(); fprintf( cout , "off = %d, k = %d\n", off, k ); }
     137:     /* we have found an acceptable k */
     138:     for( l=0; l<=j; ++l ){
     139:       if( p[off+l] ){
     140:         if( k+l >= actsiz ) error("action table overflow");
     141:         if( k+l >= memact ) memact = k+l;
     142:         amem[k+l] = p[off+l];
     143:         }
     144:       }
     145:     if( pkdebug ){
     146:       for( k=0; k<memact; k+=10){
     147:         fprintf( cout , "\t");
     148:         for( l=0; l<=9; ++l ) fprintf( cout , "%d ", amem[k+l] );
     149:         fprintf( cout , "\n");
     150:         }
     151:       }
     152:     return(k-off);
     153:
     154:     nextk: ;
     155:     }
     156:   error("no space in action table");
     157:   }
     158:
     159: go2out(){ /* output the gotos for the nontermninals */
     160:   int i, j, k, best, offset, count, cbest, times;
     161:
     162:   settab();
     163:   arrset("yygo");
     164:   offset = 1;
     165:
     166:   for( i=1; i<=nnonter; ++i ) {
     167:     go2gen(i);
     168:
     169:     /* find the best one to make default */
     170:
     171:     temp2[i] = offset;
     172:
     173:     best = -1;
     174:     times = 0;
     175:
     176:     for( j=0; j<=nstate; ++j ){ /* is j the most frequent */
     177:       if( tystate[j] == 0 ) continue;
     178:       if( tystate[j] == best ) continue;
     179:
     180:       /* is tystate[j] the most frequent */
     181:
     182:       count = 0;
     183:       cbest = tystate[j];
     184:
     185:       for( k=j; k<=nstate; ++k ) if( tystate[k]==cbest ) ++count;
     186:
     187:       if( count > times ){
     188:         best = cbest;
     189:         times = count;
     190:         }
     191:       }
     192:
     193:     /* best is now the default entry */
     194:
     195:     zzgobest += (times-1)*2;
     196:     settab();
     197:     for( j=0; j<=nstate; ++j ){
     198:       if( tystate[j] != 0 && tystate[j]!=best ){
     199:         arrval( j );
     200:         arrval( tystate[j] );
     201:         offset += 2;
     202:         zzgoent += 2;
     203:         }
     204:       }
     205:
     206:     /* now, the default */
     207:
     208:     zzgoent += 2;
     209:     arrval( -1 );
     210:     arrval( best );
     211:     offset += 2;
     212:
     213:     }
     214:
     215:   arrdone();
     216:
     217:   arrset("yypgo");
     218:   for( i=1; i<=nnonter; ++i ) arrval( temp2[i] );
     219:   arrdone();
     220:
     221:   }
     222:
     223: int g2debug = 0;
     224: go2gen(c){ /* output the gotos for nonterminal c */
     225:
     226:   int i, work, cc;
     227:   struct item *p, *q;
     228:
     229:   /* first, find nonterminals with gotos on c */
     230:
     231:   aryfil( temp1, nnonter+1, 0 );
     232:   temp1[c] = 1;
     233:
     234:   work = 1;
     235:   while( work ){
     236:     work = 0;
     237:     for( i=0; i<nprod; ++i ){
     238:       if( (cc=prdptr[i][1]-NTBASE) >= 0 ){ /* cc is a nonterminal */
     239:         if( temp1[cc] != 0 ){ /* cc has a goto on c */
     240:           cc = *prdptr[i]-NTBASE; /* thus, the left side of production i does too */
     241:           if( temp1[cc] == 0 ){
     242:             work = 1;
     243:             temp1[cc] = 1;
     244:             }
     245:           }
     246:         }
     247:       }
     248:     }
     249:
     250:   /* now, we have temp1[c] = 1 if a goto on c in closure of cc */
     251:
     252:   if( g2debug ){
     253:     settty();
     254:     fprintf( cout , "%s: gotos on ", nontrst[c].name );
     255:     for( i=0; i<=nnonter; ++i ) if( temp1[i]) fprintf( cout , "%s ", nontrst[i].name);
     256:     fprintf( cout , "\n");
     257:     }
     258:
     259:   /* now, go through and put gotos into tystate */
     260:
     261:   aryfil( tystate, nstate, 0 );
     262:   settty();
     263:   fprintf( cout , "\nnonterminal %s\n", nontrst[c].name );
     264:   for( i=0; i<nstate; ++i ){
     265:     q = pstate[i+1];
     266:     for( p=pstate[i]; p<q; ++p ){
     267:       if( (cc= *p->pitem) >= NTBASE ){
     268:         if( temp1[cc -= NTBASE] ){ /* goto on c is possible */
     269:           tystate[i] = amem[indgo[i]+c];
     270:           break;
     271:           }
     272:         }
     273:       }
     274:     if( tystate[i] ) fprintf( cout , "\t%d\t%d\n", i, tystate[i]);
     275:     }
     276:   }
     277:
     278: precftn(r,t){ /* decide a shift/reduce conflict by precedence.
     279: 			Returns 0 if action is 'do nothing',1 if action is reduce,
     280: 			2 if the action is 'error,binary operator'
     281: 			and 3 if the action is 'reduce'. */
     282:
     283:     int lp,lt;
     284:     lp = levprd[r];
     285:     lt = trmlev[t];
     286:     if ((lt==0)||((lp&03)==0))return(0);
     287:     if((lt>>3) == (lp>>3)){
     288:         return(lt&03);
     289:         }
     290:     if((lt>>3) > (lp>>3)) return(3);
     291:     return(1);
     292:     }
     293:
     294: int cdebug = 0; /* debug for common states */
     295: wract(i){ /* output state i */
     296:   /* temp1 has the actions, lastred the default */
     297:   int p, p0, p1, size;
     298:   int ntimes, tred, count, j;
     299:   struct item *q0, *q1;
     300:
     301:   /* find the best choice for lastred */
     302:
     303:   lastred = 0;
     304:   ntimes = 0;
     305:   /***** UCB MOD - full state spec if shift on error *****/
     306:   if (temp1[2] <= 0)
     307:   for( j=1; j<=nterms; ++j ){
     308:     if( temp1[j] >= 0 ) continue;
     309:     if( temp1[j]+lastred == 0 ) continue;
     310:     /* count the number of appearances of temp1[j] */
     311:     count = 0;
     312:     tred = -temp1[j];
     313:     for( p=1; p<=nterms; ++p ){
     314:       if( temp1[p]+tred == 0 ) ++count;
     315:       }
     316:     if( count >ntimes ){
     317:       lastred = tred;
     318:       ntimes = count;
     319:       }
     320:     }
     321:
     322:     /* clear out entries in temp1 which equal lastred */
     323:     for( p=1; p<= nterms; ++p ) if( temp1[p]+lastred == 0 )temp1[p]=0;
     324:
     325:     /* write out the state */
     326:
     327:     /* first, check for equality with another state */
     328:     /* see if there is a nonterminal with all dots before it. */
     329:
     330:     p0 = 0;
     331:     q1 = pstate[i+1];
     332:     for( q0=pstate[i]; q0<q1; ++q0 ){
     333:       if( (p1= *(q0->pitem) ) < NTBASE ) goto standard;
     334:       if( p0 == 0 ) p0 = p1;
     335:       else if( p0 != p1 ) goto standard;
     336:       }
     337:
     338:     /* now, all items have dots before p0 */
     339:     if( cdebug ){
     340:       settty();
     341:       fprintf( cout , "state %d, pre-nonterminal %s\n",i,nontrst[p0-NTBASE].name);
     342:       }
     343:
     344:     for( j=0; j<i; ++j ){
     345:       if( apstate[i] != apstate[j] ) continue;
     346:
     347:       /* equal positions -- check items */
     348:
     349:       if( cdebug )fprintf( cout , "states %d and %d have equal positions\n",i,j);
     350:       q1 = pstate[j+1];
     351:       for( q0=pstate[j]; q0<q1; ++q0 ){
     352:         if( *(q0->pitem) != p0 ) goto nextj;
     353:         }
     354:
     355:       /* we have a match with state j ! */
     356:
     357:       tystate[i] = -j;
     358:       zzacsave += tystate[j];
     359:       zznsave++;
     360:       wrstate(i);
     361:       return;
     362:
     363:     nextj:  ;
     364:       }
     365:
     366:
     367:   standard:
     368:     tystate[i] = 2;
     369:     wrstate(i);
     370:
     371:     size = 0;
     372:     for( p0=1; p0<=nterms; ++p0 )
     373:       if( (p1=temp1[p0])!=0 ) {
     374:     /***** UCB MOD - test actions are negative of symbol to be tested
     375: 			 this speeds up the parser as it is easy to check for
     376: 	 *****/
     377:         arrval( -trmset[p0].value );
     378:         if( p1 < 0 ) arrval( REDUCACT - p1 );
     379:         else if( p1 == ACCEPTCODE ) arrval( ACCEPTACT );
     380:         else if( p1 == ERRCODE ) arrval( ERRACT );
     381:         else arrval( SHIFTACT + p1 );
     382:         size += 2;
     383:         }
     384:     if( lastred ) arrval( REDUCACT + lastred );
     385:     else arrval( ERRACT );
     386:     tystate[i] = size+1; /* store entry size in tystate */
     387:     zzacent += (size+1);
     388:     return;
     389:   }
     390:
     391: wrstate(i){ /* writes state i */
     392:     int j0,j1,s;
     393:         struct item *pp, *qq;
     394:     settty();
     395:     fprintf( cout , "\nstate %d\n",i);
     396:     qq = pstate[i+1];
     397:     for( pp=pstate[i]; pp<qq; ++pp) fprintf( cout , "\t%s\n", writem(pp));
     398:
     399:         /* check for state equal to another */
     400:
     401:         if( tystate[i] <= 0 ){
     402:           fprintf( cout , "\n\tsame as %d\n\n", -tystate[i] );
     403:           return;
     404:           }
     405:
     406:     for( j0=1; j0<=nterms; ++j0 ) if( (j1=temp1[j0]) != 0 ){
     407:     fprintf( cout , "\n\t%s  ", symnam(j0) );
     408:              if( j1>0 ){ /* shift, error, or accept */
     409:                if( j1 == ACCEPTCODE ) fprintf( cout ,  "accept" );
     410:                else if( j1 == ERRCODE ) fprintf( cout ,  "error" );
     411:                else fprintf( cout ,  "shift %d", j1 );
     412:                }
     413:            else fprintf( cout , "reduce %d",-j1 );
     414:        }
     415:
     416:     /* output the final production */
     417:
     418:     if( lastred ) fprintf( cout , "\n\t.  reduce %d\n\n", lastred );
     419:     else fprintf( cout , "\n\t.  error\n\n" );
     420:
     421: ret:
     422:     settab();
     423:     }

#### Defined functions

apack defined in line 118; used 2 times

- in /usr/src/ucb/pascal/eyacc/ey3.c line 239-240(2)

go2 defined in line 112; used 1 times

- in line 18

go2gen defined in line 224; used 1 times

- in line 167

go2out defined in line 159; used 1 times

- in /usr/src/ucb/pascal/eyacc/ey1.c line 81

output defined in line 4; used 1 times

- in /usr/src/ucb/pascal/eyacc/ey1.c line 80

precftn defined in line 278; used 1 times

- in line 42

prred defined in line 83; used 1 times

- in line 80

wract defined in line 295; used 1 times

- in line 72

wrstate defined in line 391; used 2 times

- in line 360, 369

#### Defined variables

cdebug defined in line 294; used 2 times

- in line 339, 349

g2debug defined in line 223; used 1 times

- in line 252

pkdebug defined in line 117; used 2 times

- in line 136, 145

Last modified: 1981-01-28 Generated: 2016-12-26 | Generated by src2html V0.67 page hit count: 1341 |