/* tblcmp - table compression routines */ /* * Copyright (c) 1987, the University of California * * The United States Government has rights in this work pursuant to * contract no. DE-AC03-76SF00098 between the United States Department of * Energy and the University of California. * * This program may be redistributed. Enhancements and derivative works * may be created provided the new works, if made available to the general * public, are made available for use by anyone. */ #include "flexdef.h" /* bldtbl - build table entries for dfa state * * synopsis * int state[numecs], statenum, totaltrans, comstate, comfreq; * bldtbl( state, statenum, totaltrans, comstate, comfreq ); * * State is the statenum'th dfa state. It is indexed by equivalence class and * gives the number of the state to enter for a given equivalence class. * totaltrans is the total number of transitions out of the state. Comstate * is that state which is the destination of the most transitions out of State. * Comfreq is how many transitions there are out of State to Comstate. * * A note on terminology: * "protos" are transition tables which have a high probability of * either being redundant (a state processed later will have an identical * transition table) or nearly redundant (a state processed later will have * many of the same out-transitions). A "most recently used" queue of * protos is kept around with the hope that most states will find a proto * which is similar enough to be usable, and therefore compacting the * output tables. * "templates" are a special type of proto. If a transition table is * homogeneous or nearly homogeneous (all transitions go to the same * destination) then the odds are good that future states will also go * to the same destination state on basically the same character set. * These homogeneous states are so common when dealing with large rule * sets that they merit special attention. If the transition table were * simply made into a proto, then (typically) each subsequent, similar * state will differ from the proto for two out-transitions. One of these * out-transitions will be that character on which the proto does not go * to the common destination, and one will be that character on which the * state does not go to the common destination. Templates, on the other * hand, go to the common state on EVERY transition character, and therefore * cost only one difference. */ bldtbl( state, statenum, totaltrans, comstate, comfreq ) int state[], statenum, totaltrans, comstate, comfreq; { int extptr, extrct[2][CSIZE + 1]; int mindiff, minprot, i, d; int checkcom; /* If extptr is 0 then the first array of extrct holds the result of the * "best difference" to date, which is those transitions which occur in * "state" but not in the proto which, to date, has the fewest differences * between itself and "state". If extptr is 1 then the second array of * extrct hold the best difference. The two arrays are toggled * between so that the best difference to date can be kept around and * also a difference just created by checking against a candidate "best" * proto. */ extptr = 0; /* if the state has too few out-transitions, don't bother trying to * compact its tables */ if ( (totaltrans * 100) < (numecs * PROTO_SIZE_PERCENTAGE) ) mkentry( state, numecs, statenum, JAMSTATE, totaltrans ); else { /* checkcom is true if we should only check "state" against * protos which have the same "comstate" value */ checkcom = comfreq * 100 > totaltrans * CHECK_COM_PERCENTAGE; minprot = firstprot; mindiff = totaltrans; if ( checkcom ) { /* find first proto which has the same "comstate" */ for ( i = firstprot; i != NIL; i = protnext[i] ) if ( protcomst[i] == comstate ) { minprot = i; mindiff = tbldiff( state, minprot, extrct[extptr] ); break; } } else { /* since we've decided that the most common destination out * of "state" does not occur with a high enough frequency, * we set the "comstate" to zero, assuring that if this state * is entered into the proto list, it will not be considered * a template. */ comstate = 0; if ( firstprot != NIL ) { minprot = firstprot; mindiff = tbldiff( state, minprot, extrct[extptr] ); } } /* we now have the first interesting proto in "minprot". If * it matches within the tolerances set for the first proto, * we don't want to bother scanning the rest of the proto list * to see if we have any other reasonable matches. */ if ( mindiff * 100 > totaltrans * FIRST_MATCH_DIFF_PERCENTAGE ) { /* not a good enough match. Scan the rest of the protos */ for ( i = minprot; i != NIL; i = protnext[i] ) { d = tbldiff( state, i, extrct[1 - extptr] ); if ( d < mindiff ) { extptr = 1 - extptr; mindiff = d; minprot = i; } } } /* check if the proto we've decided on as our best bet is close * enough to the state we want to match to be usable */ if ( mindiff * 100 > totaltrans * ACCEPTABLE_DIFF_PERCENTAGE ) { /* no good. If the state is homogeneous enough, we make a * template out of it. Otherwise, we make a proto. */ if ( comfreq * 100 >= totaltrans * TEMPLATE_SAME_PERCENTAGE ) mktemplate( state, statenum, comstate ); else { mkprot( state, statenum, comstate ); mkentry( state, numecs, statenum, JAMSTATE, totaltrans ); } } else { /* use the proto */ mkentry( extrct[extptr], numecs, statenum, prottbl[minprot], mindiff ); /* if this state was sufficiently different from the proto * we built it from, make it, too, a proto */ if ( mindiff * 100 >= totaltrans * NEW_PROTO_DIFF_PERCENTAGE ) mkprot( state, statenum, comstate ); /* since mkprot added a new proto to the proto queue, it's possible * that "minprot" is no longer on the proto queue (if it happened * to have been the last entry, it would have been bumped off). * If it's not there, then the new proto took its physical place * (though logically the new proto is at the beginning of the * queue), so in that case the following call will do nothing. */ mv2front( minprot ); } } } /* cmptmps - compress template table entries * * synopsis * cmptmps(); * * template tables are compressed by using the 'template equivalence * classes', which are collections of transition character equivalence * classes which always appear together in templates - really meta-equivalence * classes. until this point, the tables for templates have been stored * up at the top end of the nxt array; they will now be compressed and have * table entries made for them. */ cmptmps() { int tmpstorage[CSIZE + 1]; register int *tmp = tmpstorage, i, j; int totaltrans, trans; peakpairs = numtemps * numecs + tblend; if ( usemecs ) { /* create equivalence classes base on data gathered on template * transitions */ nummecs = cre8ecs( tecfwd, tecbck, numecs ); } else nummecs = numecs; if ( lastdfa + numtemps + 1 >= current_max_dfas ) increase_max_dfas(); /* loop through each template */ for ( i = 1; i <= numtemps; ++i ) { totaltrans = 0; /* number of non-jam transitions out of this template */ for ( j = 1; j <= numecs; ++j ) { trans = tnxt[numecs * i + j]; if ( usemecs ) { /* the absolute value of tecbck is the meta-equivalence class * of a given equivalence class, as set up by cre8ecs */ if ( tecbck[j] > 0 ) { tmp[tecbck[j]] = trans; if ( trans > 0 ) ++totaltrans; } } else { tmp[j] = trans; if ( trans > 0 ) ++totaltrans; } } /* it is assumed (in a rather subtle way) in the skeleton that * if we're using meta-equivalence classes, the def[] entry for * all templates is the jam template, i.e., templates never default * to other non-jam table entries (e.g., another template) */ /* leave room for the jam-state after the last real state */ mkentry( tmp, nummecs, lastdfa + i + 1, JAMSTATE, totaltrans ); } } /* expand_nxt_chk - expand the next check arrays */ expand_nxt_chk() { register int old_max = current_max_xpairs; current_max_xpairs += MAX_XPAIRS_INCREMENT; ++num_reallocs; nxt = reallocate_integer_array( nxt, current_max_xpairs ); chk = reallocate_integer_array( chk, current_max_xpairs ); bzero( (char *) (chk + old_max), MAX_XPAIRS_INCREMENT * sizeof( int ) / sizeof( char ) ); } /* find_table_space - finds a space in the table for a state to be placed * * synopsis * int *state, numtrans, block_start; * int find_table_space(); * * block_start = find_table_space( state, numtrans ); * * State is the state to be added to the full speed transition table. * Numtrans is the number of out-transitions for the state. * * find_table_space() returns the position of the start of the first block (in * chk) able to accommodate the state * * In determining if a state will or will not fit, find_table_space() must take * into account the fact that an end-of-buffer state will be added at [0], * and an action number will be added in [-1]. */ int find_table_space( state, numtrans ) int *state, numtrans; { /* firstfree is the position of the first possible occurrence of two * consecutive unused records in the chk and nxt arrays */ register int i; register int *state_ptr, *chk_ptr; register int *ptr_to_last_entry_in_state; /* if there are too many out-transitions, put the state at the end of * nxt and chk */ if ( numtrans > MAX_XTIONS_FOR_FULL_INTERIOR_FIT ) { /* if table is empty, return the first available spot in chk/nxt, * which should be 1 */ if ( tblend < 2 ) return ( 1 ); i = tblend - numecs; /* start searching for table space near the * end of chk/nxt arrays */ } else i = firstfree; /* start searching for table space from the * beginning (skipping only the elements * which will definitely not hold the new * state) */ while ( 1 ) /* loops until a space is found */ { if ( i + numecs > current_max_xpairs ) expand_nxt_chk(); /* loops until space for end-of-buffer and action number are found */ while ( 1 ) { if ( chk[i - 1] == 0 ) /* check for action number space */ { if ( chk[i] == 0 ) /* check for end-of-buffer space */ break; else i += 2; /* since i != 0, there is no use checking to * see if (++i) - 1 == 0, because that's the * same as i == 0, so we skip a space */ } else ++i; if ( i + numecs > current_max_xpairs ) expand_nxt_chk(); } /* if we started search from the beginning, store the new firstfree for * the next call of find_table_space() */ if ( numtrans <= MAX_XTIONS_FOR_FULL_INTERIOR_FIT ) firstfree = i + 1; /* check to see if all elements in chk (and therefore nxt) that are * needed for the new state have not yet been taken */ state_ptr = &state[1]; ptr_to_last_entry_in_state = &chk[i + numecs + 1]; for ( chk_ptr = &chk[i + 1]; chk_ptr != ptr_to_last_entry_in_state; ++chk_ptr ) if ( *(state_ptr++) != 0 && *chk_ptr != 0 ) break; if ( chk_ptr == ptr_to_last_entry_in_state ) return ( i ); else ++i; } } /* genctbl - generates full speed compressed transition table * * synopsis * genctbl(); */ genctbl() { register int i; /* table of verify for transition and offset to next state */ printf( "static struct yy_trans_info yy_transition[%d] =\n", tblend + numecs + 1 ); printf( " {\n" ); /* We want the transition to be represented as the offset to the * next state, not the actual state number, which is what it currently is. * The offset is base[nxt[i]] - base[chk[i]]. That's just the * difference between the starting points of the two involved states * (to - from). * * first, though, we need to find some way to put in our end-of-buffer * flags and states. We do this by making a state with absolutely no * transitions. We put it at the end of the table. */ /* at this point, we're guaranteed that there's enough room in nxt[] * and chk[] to hold tblend + numecs entries. We need just two slots. * One for the action and one for the end-of-buffer transition. We * now *assume* that we're guaranteed the only character we'll try to * index this nxt/chk pair with is EOB, i.e., 0, so we don't have to * make sure there's room for jam entries for other characters. */ base[lastdfa + 1] = tblend + 2; nxt[tblend + 1] = END_OF_BUFFER_ACTION; chk[tblend + 1] = numecs + 1; chk[tblend + 2] = 1; /* anything but EOB */ nxt[tblend + 2] = 0; /* so that "make test" won't show arb. differences */ /* make sure every state has a end-of-buffer transition and an action # */ for ( i = 0; i <= lastdfa; ++i ) { chk[base[i]] = EOB_POSITION; chk[base[i] - 1] = ACTION_POSITION; nxt[base[i] - 1] = dfaacc[i].dfaacc_state; /* action number */ } for ( i = 0; i <= lastsc * 2; ++i ) nxt[base[i] - 1] = DEFAULT_ACTION; dataline = 0; datapos = 0; for ( i = 0; i <= tblend; ++i ) { if ( chk[i] == EOB_POSITION ) transition_struct_out( 0, base[lastdfa + 1] - i ); else if ( chk[i] == ACTION_POSITION ) transition_struct_out( 0, nxt[i] ); else if ( chk[i] > numecs || chk[i] == 0 ) transition_struct_out( 0, 0 ); /* unused slot */ else /* verify, transition */ transition_struct_out( chk[i], base[nxt[i]] - (i - chk[i]) ); } /* here's the final, end-of-buffer state */ transition_struct_out( chk[tblend + 1], nxt[tblend + 1] ); transition_struct_out( chk[tblend + 2], nxt[tblend + 2] ); printf( " };\n" ); printf( "\n" ); /* table of pointers to start states */ printf( "static struct yy_trans_info *yy_state_ptr[%d] =\n", lastsc * 2 + 1 ); printf( " {\n" ); for ( i = 0; i <= lastsc * 2; ++i ) printf( " &yy_transition[%d],\n", base[i] ); printf( " };\n" ); if ( useecs ) genecs(); } /* gentabs - generate data statements for the transition tables * * synopsis * gentabs(); */ gentabs() { int i, j, k, *accset, nacc, *acc_array; char clower(); /* *everything* is done in terms of arrays starting at 1, so provide * a null entry for the zero element of all FTL arrays */ static char ftl_long_decl[] = "static long int %c[%d] =\n { 0,\n"; static char ftl_short_decl[] = "static short int %c[%d] =\n { 0,\n"; static char ftl_char_decl[] = "static char %c[%d] =\n { 0,\n"; acc_array = allocate_integer_array( current_max_dfas ); nummt = 0; if ( fulltbl ) jambase = lastdfa + 1; /* home of "jam" pseudo-state */ printf( "#define YY_JAM %d\n", jamstate ); printf( "#define YY_JAM_BASE %d\n", jambase ); if ( usemecs ) printf( "#define YY_TEMPLATE %d\n", lastdfa + 2 ); if ( reject ) { /* write out accepting list and pointer list * first we generate the ACCEPT array. In the process, we compute * the indices that will go into the ALIST array, and save the * indices in the dfaacc array */ printf( accnum > 127 ? ftl_short_decl : ftl_char_decl, ACCEPT, max( numas, 1 ) + 1 ); j = 1; /* index into ACCEPT array */ for ( i = 1; i <= lastdfa; ++i ) { acc_array[i] = j; if ( accsiz[i] != 0 ) { accset = dfaacc[i].dfaacc_set; nacc = accsiz[i]; if ( trace ) fprintf( stderr, "state # %d accepts: ", i ); for ( k = 1; k <= nacc; ++k ) { ++j; mkdata( accset[k] ); if ( trace ) { fprintf( stderr, "[%d]", accset[k] ); if ( k < nacc ) fputs( ", ", stderr ); else putc( '\n', stderr ); } } } } /* add accepting number for the "jam" state */ acc_array[i] = j; dataend(); } else { for ( i = 1; i <= lastdfa; ++i ) acc_array[i] = dfaacc[i].dfaacc_state; acc_array[i] = 0; /* add (null) accepting number for jam state */ } /* spit out ALIST array. If we're doing "reject", it'll be pointers * into the ACCEPT array. Otherwise it's actual accepting numbers. * In either case, we just dump the numbers. */ /* "lastdfa + 2" is the size of ALIST; includes room for FTL arrays * beginning at 0 and for "jam" state */ k = lastdfa + 2; if ( reject ) /* we put a "cap" on the table associating lists of accepting * numbers with state numbers. This is needed because we tell * where the end of an accepting list is by looking at where * the list for the next state starts. */ ++k; #ifdef UNSIGNED_CHAR printf( ftl_short_decl, ALIST, k ); #else printf( ((reject && numas > 126) || accnum > 127) ? ftl_short_decl : ftl_char_decl, ALIST, k ); #endif /* set up default actions */ for ( i = 1; i <= lastsc * 2; ++i ) acc_array[i] = DEFAULT_ACTION; acc_array[end_of_buffer_state] = END_OF_BUFFER_ACTION; for ( i = 1; i <= lastdfa; ++i ) { mkdata( acc_array[i] ); if ( ! reject && trace && acc_array[i] ) fprintf( stderr, "state # %d accepts: [%d]\n", i, acc_array[i] ); } /* add entry for "jam" state */ mkdata( acc_array[i] ); if ( reject ) /* add "cap" for the list */ mkdata( acc_array[i] ); dataend(); if ( useecs ) genecs(); if ( usemecs ) { /* write out meta-equivalence classes (used to index templates with) */ if ( trace ) fputs( "\n\nMeta-Equivalence Classes:\n", stderr ); printf( ftl_char_decl, MATCHARRAY, numecs + 1 ); for ( i = 1; i <= numecs; ++i ) { if ( trace ) fprintf( stderr, "%d = %d\n", i, abs( tecbck[i] ) ); mkdata( abs( tecbck[i] ) ); } dataend(); } if ( ! fulltbl ) { int total_states = lastdfa + numtemps; printf( tblend > MAX_SHORT ? ftl_long_decl : ftl_short_decl, BASEARRAY, total_states + 1 ); for ( i = 1; i <= lastdfa; ++i ) { register int d = def[i]; if ( base[i] == JAMSTATE ) base[i] = jambase; if ( d == JAMSTATE ) def[i] = jamstate; else if ( d < 0 ) { /* template reference */ ++tmpuses; def[i] = lastdfa - d + 1; } mkdata( base[i] ); } /* generate jam state's base index */ mkdata( base[i] ); for ( ++i /* skip jam state */; i <= total_states; ++i ) { mkdata( base[i] ); def[i] = jamstate; } dataend(); printf( tblend > MAX_SHORT ? ftl_long_decl : ftl_short_decl, DEFARRAY, total_states + 1 ); for ( i = 1; i <= total_states; ++i ) mkdata( def[i] ); dataend(); printf( lastdfa > MAX_SHORT ? ftl_long_decl : ftl_short_decl, NEXTARRAY, tblend + 1 ); for ( i = 1; i <= tblend; ++i ) { if ( nxt[i] == 0 || chk[i] == 0 ) nxt[i] = jamstate; /* new state is the JAM state */ mkdata( nxt[i] ); } dataend(); printf( lastdfa > MAX_SHORT ? ftl_long_decl : ftl_short_decl, CHECKARRAY, tblend + 1 ); for ( i = 1; i <= tblend; ++i ) { if ( chk[i] == 0 ) ++nummt; mkdata( chk[i] ); } dataend(); } } /* generate equivalence-class tables */ genecs() { register int i, j; static char ftl_char_decl[] = "static char %c[%d] =\n { 0,\n"; int numrows; printf( ftl_char_decl, ECARRAY, CSIZE + 1 ); for ( i = 1; i <= CSIZE; ++i ) { if ( caseins && (i >= 'A') && (i <= 'Z') ) ecgroup[i] = ecgroup[clower( i )]; ecgroup[i] = abs( ecgroup[i] ); mkdata( ecgroup[i] ); } dataend(); if ( trace ) { fputs( "\n\nEquivalence Classes:\n\n", stderr ); numrows = (CSIZE + 1) / 8; for ( j = 1; j <= numrows; ++j ) { for ( i = j; i <= CSIZE; i = i + numrows ) { if ( i >= 1 && i <= 31 ) fprintf( stderr, "^%c = %-2d", 'A' + i - 1, ecgroup[i] ); else if ( i >= 32 && i <= 126 ) fprintf( stderr, " %c = %-2d", i, ecgroup[i] ); else if ( i == 127 ) fprintf( stderr, "^@ = %-2d", ecgroup[i] ); else fprintf( stderr, "\nSomething Weird: %d = %d\n", i, ecgroup[i] ); putc( '\t', stderr ); } putc( '\n', stderr ); } } } /* inittbl - initialize transition tables * * synopsis * inittbl(); * * Initializes "firstfree" to be one beyond the end of the table. Initializes * all "chk" entries to be zero. Note that templates are built in their * own tbase/tdef tables. They are shifted down to be contiguous * with the non-template entries during table generation. */ inittbl() { register int i; bzero( (char *) chk, current_max_xpairs * sizeof( int ) / sizeof( char ) ); tblend = 0; firstfree = tblend + 1; numtemps = 0; if ( usemecs ) { /* set up doubly-linked meta-equivalence classes * these are sets of equivalence classes which all have identical * transitions out of TEMPLATES */ tecbck[1] = NIL; for ( i = 2; i <= numecs; ++i ) { tecbck[i] = i - 1; tecfwd[i - 1] = i; } tecfwd[numecs] = NIL; } } /* make_tables - generate transition tables * * synopsis * make_tables(); * * Generates transition tables and finishes generating output file */ make_tables() { if ( fullspd ) { /* need to define YY_TRANS_OFFSET_TYPE as a size large * enough to hold the biggest offset */ int total_table_size = tblend + numecs + 1; printf( "#define YY_TRANS_OFFSET_TYPE %s\n", total_table_size > MAX_SHORT ? "long" : "short" ); } if ( fullspd || fulltbl ) skelout(); /* compute the tables and copy them to output file */ if ( fullspd ) genctbl(); else gentabs(); skelout(); (void) fclose( temp_action_file ); temp_action_file = fopen( action_file_name, "r" ); /* copy prolog from action_file to output file */ action_out(); skelout(); /* copy actions from action_file to output file */ action_out(); skelout(); /* copy remainder of input to output */ line_directive_out( stdout ); (void) flexscan(); /* copy remainder of input to output */ } /* mkdeftbl - make the default, "jam" table entries * * synopsis * mkdeftbl(); */ mkdeftbl() { int i; jamstate = lastdfa + 1; if ( tblend + numecs > current_max_xpairs ) expand_nxt_chk(); for ( i = 1; i <= numecs; ++i ) { nxt[tblend + i] = 0; chk[tblend + i] = jamstate; } jambase = tblend; base[jamstate] = jambase; /* should generate a run-time array bounds check if * ever used as a default */ def[jamstate] = BAD_SUBSCRIPT; tblend += numecs; ++numtemps; } /* mkentry - create base/def and nxt/chk entries for transition array * * synopsis * int state[numchars + 1], numchars, statenum, deflink, totaltrans; * mkentry( state, numchars, statenum, deflink, totaltrans ); * * "state" is a transition array "numchars" characters in size, "statenum" * is the offset to be used into the base/def tables, and "deflink" is the * entry to put in the "def" table entry. If "deflink" is equal to * "JAMSTATE", then no attempt will be made to fit zero entries of "state" * (i.e., jam entries) into the table. It is assumed that by linking to * "JAMSTATE" they will be taken care of. In any case, entries in "state" * marking transitions to "SAME_TRANS" are treated as though they will be * taken care of by whereever "deflink" points. "totaltrans" is the total * number of transitions out of the state. If it is below a certain threshold, * the tables are searched for an interior spot that will accommodate the * state array. */ mkentry( state, numchars, statenum, deflink, totaltrans ) register int *state; int numchars, statenum, deflink, totaltrans; { register int minec, maxec, i, baseaddr; int tblbase, tbllast; if ( totaltrans == 0 ) { /* there are no out-transitions */ if ( deflink == JAMSTATE ) base[statenum] = JAMSTATE; else base[statenum] = 0; def[statenum] = deflink; return; } for ( minec = 1; minec <= numchars; ++minec ) { if ( state[minec] != SAME_TRANS ) if ( state[minec] != 0 || deflink != JAMSTATE ) break; } if ( totaltrans == 1 ) { /* there's only one out-transition. Save it for later to fill * in holes in the tables. */ stack1( statenum, minec, state[minec], deflink ); return; } for ( maxec = numchars; maxec > 0; --maxec ) { if ( state[maxec] != SAME_TRANS ) if ( state[maxec] != 0 || deflink != JAMSTATE ) break; } /* Whether we try to fit the state table in the middle of the table * entries we have already generated, or if we just take the state * table at the end of the nxt/chk tables, we must make sure that we * have a valid base address (i.e., non-negative). Note that not only are * negative base addresses dangerous at run-time (because indexing the * next array with one and a low-valued character might generate an * array-out-of-bounds error message), but at compile-time negative * base addresses denote TEMPLATES. */ /* find the first transition of state that we need to worry about. */ if ( totaltrans * 100 <= numchars * INTERIOR_FIT_PERCENTAGE ) { /* attempt to squeeze it into the middle of the tabls */ baseaddr = firstfree; while ( baseaddr < minec ) { /* using baseaddr would result in a negative base address below * find the next free slot */ for ( ++baseaddr; chk[baseaddr] != 0; ++baseaddr ) ; } if ( baseaddr + maxec - minec >= current_max_xpairs ) expand_nxt_chk(); for ( i = minec; i <= maxec; ++i ) if ( state[i] != SAME_TRANS ) if ( state[i] != 0 || deflink != JAMSTATE ) if ( chk[baseaddr + i - minec] != 0 ) { /* baseaddr unsuitable - find another */ for ( ++baseaddr; baseaddr < current_max_xpairs && chk[baseaddr] != 0; ++baseaddr ) ; if ( baseaddr + maxec - minec >= current_max_xpairs ) expand_nxt_chk(); /* reset the loop counter so we'll start all * over again next time it's incremented */ i = minec - 1; } } else { /* ensure that the base address we eventually generate is * non-negative */ baseaddr = max( tblend + 1, minec ); } tblbase = baseaddr - minec; tbllast = tblbase + maxec; if ( tbllast >= current_max_xpairs ) expand_nxt_chk(); base[statenum] = tblbase; def[statenum] = deflink; for ( i = minec; i <= maxec; ++i ) if ( state[i] != SAME_TRANS ) if ( state[i] != 0 || deflink != JAMSTATE ) { nxt[tblbase + i] = state[i]; chk[tblbase + i] = statenum; } if ( baseaddr == firstfree ) /* find next free slot in tables */ for ( ++firstfree; chk[firstfree] != 0; ++firstfree ) ; tblend = max( tblend, tbllast ); } /* mk1tbl - create table entries for a state (or state fragment) which * has only one out-transition * * synopsis * int state, sym, onenxt, onedef; * mk1tbl( state, sym, onenxt, onedef ); */ mk1tbl( state, sym, onenxt, onedef ) int state, sym, onenxt, onedef; { if ( firstfree < sym ) firstfree = sym; while ( chk[firstfree] != 0 ) if ( ++firstfree >= current_max_xpairs ) expand_nxt_chk(); base[state] = firstfree - sym; def[state] = onedef; chk[firstfree] = state; nxt[firstfree] = onenxt; if ( firstfree > tblend ) { tblend = firstfree++; if ( firstfree >= current_max_xpairs ) expand_nxt_chk(); } } /* mkprot - create new proto entry * * synopsis * int state[], statenum, comstate; * mkprot( state, statenum, comstate ); */ mkprot( state, statenum, comstate ) int state[], statenum, comstate; { int i, slot, tblbase; if ( ++numprots >= MSP || numecs * numprots >= PROT_SAVE_SIZE ) { /* gotta make room for the new proto by dropping last entry in * the queue */ slot = lastprot; lastprot = protprev[lastprot]; protnext[lastprot] = NIL; } else slot = numprots; protnext[slot] = firstprot; if ( firstprot != NIL ) protprev[firstprot] = slot; firstprot = slot; prottbl[slot] = statenum; protcomst[slot] = comstate; /* copy state into save area so it can be compared with rapidly */ tblbase = numecs * (slot - 1); for ( i = 1; i <= numecs; ++i ) protsave[tblbase + i] = state[i]; } /* mktemplate - create a template entry based on a state, and connect the state * to it * * synopsis * int state[], statenum, comstate, totaltrans; * mktemplate( state, statenum, comstate, totaltrans ); */ mktemplate( state, statenum, comstate ) int state[], statenum, comstate; { int i, numdiff, tmpbase, tmp[CSIZE + 1]; char transset[CSIZE + 1]; int tsptr; ++numtemps; tsptr = 0; /* calculate where we will temporarily store the transition table * of the template in the tnxt[] array. The final transition table * gets created by cmptmps() */ tmpbase = numtemps * numecs; if ( tmpbase + numecs >= current_max_template_xpairs ) { current_max_template_xpairs += MAX_TEMPLATE_XPAIRS_INCREMENT; ++num_reallocs; tnxt = reallocate_integer_array( tnxt, current_max_template_xpairs ); } for ( i = 1; i <= numecs; ++i ) if ( state[i] == 0 ) tnxt[tmpbase + i] = 0; else { transset[tsptr++] = i; tnxt[tmpbase + i] = comstate; } if ( usemecs ) mkeccl( transset, tsptr, tecfwd, tecbck, numecs ); mkprot( tnxt + tmpbase, -numtemps, comstate ); /* we rely on the fact that mkprot adds things to the beginning * of the proto queue */ numdiff = tbldiff( state, firstprot, tmp ); mkentry( tmp, numecs, statenum, -numtemps, numdiff ); } /* mv2front - move proto queue element to front of queue * * synopsis * int qelm; * mv2front( qelm ); */ mv2front( qelm ) int qelm; { if ( firstprot != qelm ) { if ( qelm == lastprot ) lastprot = protprev[lastprot]; protnext[protprev[qelm]] = protnext[qelm]; if ( protnext[qelm] != NIL ) protprev[protnext[qelm]] = protprev[qelm]; protprev[qelm] = NIL; protnext[qelm] = firstprot; protprev[firstprot] = qelm; firstprot = qelm; } } /* ntod - convert an ndfa to a dfa * * synopsis * ntod(); * * creates the dfa corresponding to the ndfa we've constructed. the * dfa starts out in state #1. */ ntod() { int *accset, ds, nacc, newds; int duplist[CSIZE + 1], sym, hashval, numstates, dsize; int targfreq[CSIZE + 1], targstate[CSIZE + 1], state[CSIZE + 1]; int *nset, *dset; int targptr, totaltrans, i, comstate, comfreq, targ; int *epsclosure(), snstods(), symlist[CSIZE + 1]; /* this is so find_table_space(...) will know where to start looking in * chk/nxt for unused records for space to put in the state */ if ( fullspd ) firstfree = 0; accset = allocate_integer_array( accnum + 1 ); nset = allocate_integer_array( current_max_dfa_size ); todo_head = todo_next = 0; #define ADD_QUEUE_ELEMENT(element) \ if ( ++element >= current_max_dfas ) \ { /* check for queue overflowing */ \ if ( todo_head == 0 ) \ increase_max_dfas(); \ else \ element = 0; \ } #define NEXT_QUEUE_ELEMENT(element) ((element + 1) % (current_max_dfas + 1)) for ( i = 0; i <= CSIZE; ++i ) { duplist[i] = NIL; symlist[i] = false; } for ( i = 0; i <= accnum; ++i ) accset[i] = NIL; if ( trace ) { dumpnfa( scset[1] ); fputs( "\n\nDFA Dump:\n\n", stderr ); } inittbl(); if ( fullspd ) { for ( i = 0; i <= numecs; ++i ) state[i] = 0; place_state( state, 0, 0 ); } if ( fulltbl ) { /* declare it "short" because it's a real long-shot that that * won't be large enough */ printf( "static short int %c[][%d] =\n {\n", NEXTARRAY, numecs + 1 ); /* '}' so vi doesn't get too confused */ /* generate 0 entries for state #0 */ for ( i = 0; i <= numecs; ++i ) mk2data( 0 ); /* force ',' and dataflush() next call to mk2data */ datapos = NUMDATAITEMS; /* force extra blank line next dataflush() */ dataline = NUMDATALINES; } /* create the first states */ for ( i = 1; i <= lastsc * 2; ++i ) { numstates = 1; /* for each start condition, make one state for the case when * we're at the beginning of the line (the '%' operator) and * one for the case when we're not */ if ( i % 2 == 1 ) nset[numstates] = scset[(i / 2) + 1]; else nset[numstates] = mkbranch( scbol[i / 2], scset[i / 2] ); nset = epsclosure( nset, &numstates, accset, &nacc, &hashval ); if ( snstods( nset, numstates, accset, nacc, hashval, &ds ) ) { numas = numas + nacc; totnst = totnst + numstates; todo[todo_next] = ds; ADD_QUEUE_ELEMENT(todo_next); } } if ( fulltbl ) { if ( ! snstods( nset, 0, accset, 0, 0, &end_of_buffer_state ) ) flexfatal( "could not create unique end-of-buffer state" ); numas += 1; todo[todo_next] = end_of_buffer_state; ADD_QUEUE_ELEMENT(todo_next); } while ( todo_head != todo_next ) { targptr = 0; totaltrans = 0; for ( i = 1; i <= numecs; ++i ) state[i] = 0; ds = todo[todo_head]; todo_head = NEXT_QUEUE_ELEMENT(todo_head); dset = dss[ds]; dsize = dfasiz[ds]; if ( trace ) fprintf( stderr, "state # %d:\n", ds ); sympartition( dset, dsize, symlist, duplist ); for ( sym = 1; sym <= numecs; ++sym ) { if ( symlist[sym] ) { symlist[sym] = 0; if ( duplist[sym] == NIL ) { /* symbol has unique out-transitions */ numstates = symfollowset( dset, dsize, sym, nset ); nset = epsclosure( nset, &numstates, accset, &nacc, &hashval ); if ( snstods( nset, numstates, accset, nacc, hashval, &newds ) ) { totnst = totnst + numstates; todo[todo_next] = newds; ADD_QUEUE_ELEMENT(todo_next); numas = numas + nacc; } state[sym] = newds; if ( trace ) fprintf( stderr, "\t%d\t%d\n", sym, newds ); targfreq[++targptr] = 1; targstate[targptr] = newds; ++numuniq; } else { /* sym's equivalence class has the same transitions * as duplist(sym)'s equivalence class */ targ = state[duplist[sym]]; state[sym] = targ; if ( trace ) fprintf( stderr, "\t%d\t%d\n", sym, targ ); /* update frequency count for destination state */ i = 0; while ( targstate[++i] != targ ) ; ++targfreq[i]; ++numdup; } ++totaltrans; duplist[sym] = NIL; } } numsnpairs = numsnpairs + totaltrans; if ( caseins && ! useecs ) { register int j; for ( i = 'A', j = 'a'; i <= 'Z'; ++i, ++j ) state[i] = state[j]; } if ( fulltbl ) { /* supply array's 0-element */ if ( ds == end_of_buffer_state ) mk2data( 0 ); else mk2data( end_of_buffer_state ); for ( i = 1; i <= numecs; ++i ) mk2data( state[i] ); /* force ',' and dataflush() next call to mk2data */ datapos = NUMDATAITEMS; /* force extra blank line next dataflush() */ dataline = NUMDATALINES; } else if ( fullspd ) place_state( state, ds, totaltrans ); else { /* determine which destination state is the most common, and * how many transitions to it there are */ comfreq = 0; comstate = 0; for ( i = 1; i <= targptr; ++i ) if ( targfreq[i] > comfreq ) { comfreq = targfreq[i]; comstate = targstate[i]; } bldtbl( state, ds, totaltrans, comstate, comfreq ); } } if ( fulltbl ) dataend(); else { cmptmps(); /* create compressed template entries */ /* create tables for all the states with only one out-transition */ while ( onesp > 0 ) { mk1tbl( onestate[onesp], onesym[onesp], onenext[onesp], onedef[onesp] ); --onesp; } mkdeftbl(); } } /* place_state - place a state into full speed transition table * * synopsis * int *state, statenum, transnum; * place_state( state, statenum, transnum ); * * State is the statenum'th state. It is indexed by equivalence class and * gives the number of the state to enter for a given equivalence class. * Transnum is the number of out-transitions for the state. */ place_state( state, statenum, transnum ) int *state, statenum, transnum; { register int i; register int *state_ptr; int position = find_table_space( state, transnum ); /* base is the table of start positions */ base[statenum] = position; /* put in action number marker; this non-zero number makes sure that * find_table_space() knows that this position in chk/nxt is taken * and should not be used for another accepting number in another state */ chk[position - 1] = 1; /* put in end-of-buffer marker; this is for the same purposes as above */ chk[position] = 1; /* place the state into chk and nxt */ state_ptr = &state[1]; for ( i = 1; i <= numecs; ++i, ++state_ptr ) if ( *state_ptr != 0 ) { chk[position + i] = i; nxt[position + i] = *state_ptr; } if ( position + numecs > tblend ) tblend = position + numecs; } /* stack1 - save states with only one out-transition to be processed later * * synopsis * int statenum, sym, nextstate, deflink; * stack1( statenum, sym, nextstate, deflink ); * * if there's room for another state one the "one-transition" stack, the * state is pushed onto it, to be processed later by mk1tbl. If there's * no room, we process the sucker right now. */ stack1( statenum, sym, nextstate, deflink ) int statenum, sym, nextstate, deflink; { if ( onesp >= ONE_STACK_SIZE ) mk1tbl( statenum, sym, nextstate, deflink ); else { ++onesp; onestate[onesp] = statenum; onesym[onesp] = sym; onenext[onesp] = nextstate; onedef[onesp] = deflink; } } /* tbldiff - compute differences between two state tables * * synopsis * int state[], pr, ext[]; * int tbldiff, numdifferences; * numdifferences = tbldiff( state, pr, ext ) * * "state" is the state array which is to be extracted from the pr'th * proto. "pr" is both the number of the proto we are extracting from * and an index into the save area where we can find the proto's complete * state table. Each entry in "state" which differs from the corresponding * entry of "pr" will appear in "ext". * Entries which are the same in both "state" and "pr" will be marked * as transitions to "SAME_TRANS" in "ext". The total number of differences * between "state" and "pr" is returned as function value. Note that this * number is "numecs" minus the number of "SAME_TRANS" entries in "ext". */ int tbldiff( state, pr, ext ) int state[], pr, ext[]; { register int i, *sp = state, *ep = ext, *protp; register int numdiff = 0; protp = &protsave[numecs * (pr - 1)]; for ( i = numecs; i > 0; --i ) { if ( *++protp == *++sp ) *++ep = SAME_TRANS; else { *++ep = *sp; ++numdiff; } } return ( numdiff ); }