/**************************************************************************** Copyright (c) 2006 - 2010, Armin Biere, Johannes Kepler University. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. ****************************************************************************/ #include #include #include #include #include #include #include #include "picosat.h" /* By default code for 'all different constraints' is disabled, since 'NADC' * is defined. #define NADC */ /* By default we enable failed literals, since 'NFL' is undefined. * */ #define NFL /* By default we 'detach satisfied (large) clauses', e.g. NDSC undefined. * #define NDSC */ /* Do not use luby restart schedule instead of inner/outer. * #define NLUBY */ // #define VISCORES /* keep this disabled */ #ifdef VISCORES // #define WRITEGIF #endif #ifdef VISCORES #ifndef WRITEGIF #include /* for 'usleep' */ #endif #endif #define MINRESTART 100 /* minimum restart interval */ #define MAXRESTART 1000000 /* maximum restart interval */ #define RDECIDE 1000 /* interval of random decisions */ #define FRESTART 110 /* restart increase factor in percent */ #define FREDUCE 110 /* reduce increase factor in percent */ #define FFLIPPED 10000 /* flipped reduce factor */ #define FFLIPPEDPREC 10000000/* flipped reduce factor precision */ #ifndef TRACE #define NO_BINARY_CLAUSES /* store binary clauses more compactly */ #endif /* For debugging purposes you may want to define 'LOGGING', which actually * can be enforced by using the '--log' option for the configure script. */ #ifdef LOGGING #define LOG(code) do { code; } while (0) #else #define LOG(code) do { } while (0) #endif #define NOLOG(code) do { } while (0) /* log exception */ #define ONLYLOG(code) do { code; } while (0) /* force logging */ #define FALSE ((Val)-1) #define UNDEF ((Val)0) #define TRUE ((Val)1) #define COMPACT_TRACECHECK_TRACE_FMT 0 #define EXTENDED_TRACECHECK_TRACE_FMT 1 #define RUP_TRACE_FMT 2 #define NEWN(p,n) do { (p) = new (sizeof (*(p)) * (n)); } while (0) #define CLRN(p,n) do { memset ((p), 0, sizeof (*(p)) * (n)); } while (0) #define CLR(p) CLRN(p,1) #define DELETEN(p,n) \ do { delete (p, sizeof (*(p)) * (n)); (p) = 0; } while (0) #define RESIZEN(p,old_num,new_num) \ do { \ size_t old_size = sizeof (*(p)) * (old_num); \ size_t new_size = sizeof (*(p)) * (new_num); \ (p) = resize ((p), old_size, new_size) ; \ } while (0) #define ENLARGE(start,head,end) \ do { \ unsigned old_num = (unsigned)((end) - (start)); \ size_t new_num = old_num ? (2 * old_num) : 1; \ unsigned count = (head) - (start); \ assert ((start) <= (start)); \ RESIZEN((start),old_num,new_num); \ (head) = (start) + count; \ (end) = (start) + new_num; \ } while (0) #define NOTLIT(l) (lits + (1 ^ ((l) - lits))) #define LIT2IDX(l) ((unsigned)((l) - lits) / 2) #define LIT2IMPLS(l) (impls + (unsigned)((l) - lits)) #define LIT2INT(l) (LIT2SGN(l) * LIT2IDX(l)) #define LIT2SGN(l) (((unsigned)((l) - lits) & 1) ? -1 : 1) #define LIT2VAR(l) (vars + LIT2IDX(l)) #define LIT2HTPS(l) (htps + (unsigned)((l) - lits)) #define LIT2JWH(l) (jwh + ((l) - lits)) #ifndef NDSC #define LIT2DHTPS(l) (dhtps + (unsigned)((l) - lits)) #endif #ifdef NO_BINARY_CLAUSES typedef unsigned long Wrd; #define ISLITREASON(cls) (1&(Wrd)cls) #define LIT2REASON(lit) \ (assert (lit->val==TRUE), ((Cls*)(1 + (2*(lit - lits))))) #define REASON2LIT(cls) ((Lit*)(lits + ((Wrd)cls)/2)) #endif #define ENDOFCLS(c) ((void*)((c)->lits + (c)->size)) #define SOC ((oclauses == ohead) ? lclauses : oclauses) #define EOC lhead #define NXC(p) (((p) + 1 == ohead) ? lclauses : (p) + 1) #define OIDX2IDX(idx) (2 * ((idx) + 1)) #define LIDX2IDX(idx) (2 * (idx) + 1) #define ISLIDX(idx) ((idx)&1) #define IDX2OIDX(idx) (assert(!ISLIDX(idx)), (idx)/2 - 1) #define IDX2LIDX(idx) (assert(ISLIDX(idx)), (idx)/2) #define EXPORTIDX(idx) \ ((ISLIDX(idx) ? (IDX2LIDX (idx) + (ohead - oclauses)) : IDX2OIDX(idx)) + 1) #define IDX2CLS(i) \ (assert(i), (ISLIDX(i) ? lclauses : oclauses)[(i)/2 - !ISLIDX(i)]) #define IDX2ZHN(i) (assert(i), (ISLIDX(i) ? zhains[(i)/2] : 0)) #define CLS2TRD(c) (((Trd*)(c)) - 1) #define CLS2IDX(c) ((((Trd*)(c)) - 1)->idx) #define CLS2ACT(c) \ ((Act*)((assert((c)->learned)),assert((c)->size>2),ENDOFCLS(c))) #define VAR2LIT(v) (lits + 2 * ((v) - vars)) #define VAR2RNK(v) (rnks + ((v) - vars)) #define RNK2LIT(r) (lits + 2 * ((r) - rnks)) #define RNK2VAR(r) (vars + ((r) - rnks)) #define BLK_FILL_BYTES 8 #define SIZE_OF_BLK (sizeof (Blk) - BLK_FILL_BYTES) #define PTR2BLK(void_ptr) \ ((void_ptr) ? (Blk*)(((char*)(void_ptr)) - SIZE_OF_BLK) : 0) #define AVERAGE(a,b) ((b) ? (((double)a) / (double)(b)) : 0.0) #define PERCENT(a,b) (100.0 * AVERAGE(a,b)) #define ABORT(msg) \ do { \ fputs ("*** picosat: " msg "\n", stderr); \ abort (); \ } while (0) #define ABORTIF(cond,msg) \ do { \ if (!(cond)) break; \ ABORT (msg); \ } while (0) #define ZEROFLT (0x00000000u) #define INFFLT (0xffffffffu) #define FLTCARRY (1u << 25) #define FLTMSB (1u << 24) #define FLTMAXMANTISSA (FLTMSB - 1) #define FLTMANTISSA(d) ((d) & FLTMAXMANTISSA) #define FLTEXPONENT(d) ((int)((d) >> 24) - 128) #define FLTMINEXPONENT (-128) #define FLTMAXEXPONENT (127) #define cmpswapflt(a,b) \ do { \ Flt tmp; \ if (((a) < (b))) \ { \ tmp = (a); \ (a) = (b); \ (b) = tmp; \ } \ } while (0) #define unpackflt(u,m,e) \ do { \ (m) = FLTMANTISSA(u); \ (e) = FLTEXPONENT(u); \ (m) |= FLTMSB; \ } while (0) #define INSERTION_SORT_LIMIT 10 #define internal_sorting_swap(T,p,q) \ do { \ T tmp = *(q); \ *(q) = *(p); \ *(p) = tmp; \ } while (0) #define internal_sorting_cmpswap(T,cmp,p,q) \ do { \ if ((cmp) (*(p), *(q)) > 0) \ internal_sorting_swap (T, p, q); \ } while(0) #define internal_quicksort_partition(T,cmp,a,l,r) \ do { \ T pivot; \ int j; \ i = (l) - 1; /* result in 'i' */ \ j = (r); \ pivot = (a)[j]; \ for (;;) \ { \ while ((cmp) ((a)[++i], pivot) < 0) \ ; \ while ((cmp) (pivot, (a)[--j]) < 0) \ if (j == (l)) \ break; \ if (i >= j) \ break; \ internal_sorting_swap (T, (a) + i, (a) + j); \ } \ internal_sorting_swap (T, (a) + i, (a) + (r)); \ } while(0) #define internal_quicksort(T,cmp,a,n) \ do { \ int l = 0, r = (n) - 1, m, ll, rr, i; \ assert (ihead == indices); \ if (r - l <= INSERTION_SORT_LIMIT) \ break; \ for (;;) \ { \ m = (l + r) / 2; \ internal_sorting_swap (T, (a) + m, (a) + r - 1); \ internal_sorting_cmpswap (T, cmp, (a) + l, (a) + r - 1); \ internal_sorting_cmpswap (T, cmp, (a) + l, (a) + r); \ internal_sorting_cmpswap (T, cmp, (a) + r - 1, (a) + r); \ internal_quicksort_partition (T, cmp, (a), l + 1, r - 1); \ if (i - l < r - i) \ { \ ll = i + 1; \ rr = r; \ r = i - 1; \ } \ else \ { \ ll = l; \ rr = i - 1; \ l = i + 1; \ } \ if (r - l > INSERTION_SORT_LIMIT) \ { \ assert (rr - ll > INSERTION_SORT_LIMIT); \ if (ihead == eoi) \ ENLARGE (indices, ihead, eoi); \ *ihead++ = ll; \ if (ihead == eoi) \ ENLARGE (indices, ihead, eoi); \ *ihead++ = rr; \ } \ else if (rr - ll > INSERTION_SORT_LIMIT) \ { \ l = ll; \ r = rr; \ } \ else if (ihead > indices) \ { \ r = *--ihead; \ l = *--ihead; \ } \ else \ break; \ } \ } while (0) #define internal_insertion_sort(T,cmp,a,n) \ do { \ T pivot; \ int l = 0, r = (n) - 1, i, j; \ for (i = r; i > l; i--) \ internal_sorting_cmpswap (T, cmp, (a) + i - 1, (a) + i); \ for (i = l + 2; i <= r; i++) \ { \ j = i; \ pivot = (a)[i]; \ while ((cmp) (pivot, (a)[j - 1]) < 0) \ { \ (a)[j] = (a)[j - 1]; \ j--; \ } \ (a)[j] = pivot; \ } \ } while (0) #ifdef NDEBUG #define check_sorted(cmp,a,n) do { } while(0) #else #define check_sorted(cmp,a,n) \ do { \ int i; \ for (i = 0; i < (n) - 1; i++) \ assert ((cmp) ((a)[i], (a)[i + 1]) <= 0); \ } while(0) #endif #define sort(T,cmp,a,n) \ do { \ T * aa = (a); \ int nn = (n); \ internal_quicksort (T, cmp, aa, nn); \ internal_insertion_sort (T, cmp, aa, nn); \ assert (ihead == indices); \ check_sorted (cmp, aa, nn); \ } while (0) #define WRDSZ (sizeof (long) * 8) typedef unsigned Flt; /* 32 bit deterministic soft float */ typedef Flt Act; /* clause and variable activity */ typedef struct Blk Blk; /* allocated memory block */ typedef struct Cls Cls; /* clause */ typedef struct Lit Lit; /* literal */ typedef struct Rnk Rnk; /* variable to score mapping */ typedef signed char Val; /* TRUE, UNDEF, FALSE */ typedef struct Var Var; /* variable */ #ifdef TRACE typedef struct Trd Trd; /* trace data for clauses */ typedef struct Zhn Zhn; /* compressed chain (=zain) data */ typedef unsigned char Znt; /* compressed antecedent data */ #endif #ifdef NO_BINARY_CLAUSES typedef struct Ltk Ltk; struct Ltk { Lit ** start; unsigned count : WRDSZ == 32 ? 27 : 32; unsigned ldsize : WRDSZ == 32 ? 5 : 32; }; #endif struct Lit { Val val; }; struct Var { unsigned mark : 1; unsigned resolved : 1; unsigned phase : 1; unsigned assigned : 1; unsigned used : 1; unsigned failed : 1; #ifdef TRACE unsigned core : 1; #endif unsigned level : WRDSZ == 32 ? 24 : 32; Cls *reason; #ifndef NADC Lit ** inado; Lit ** ado; Lit *** adotabpos; #endif }; struct Rnk { Act score; unsigned pos : 30; /* 0 iff not on heap */ unsigned moreimportant : 1; unsigned lessimportant : 1; }; struct Cls { unsigned size; unsigned learned:1; unsigned collect:1; unsigned locked:1; unsigned fixed:1; unsigned used:1; #ifndef NDEBUG unsigned connected:1; #endif #ifdef TRACE unsigned core:1; unsigned collected:1; #endif Cls *next[2]; Lit *lits[2]; }; #ifdef TRACE struct Zhn { unsigned ref:31; unsigned core:1; Znt * liz; Znt znt[0]; }; struct Trd { unsigned idx; Cls cls[0]; }; #endif struct Blk { #ifndef NDEBUG union { size_t size; /* this is what we really use */ void *as_two_ptrs[2]; /* 2 * sizeof (void*) alignment of data */ } header; #endif char data[BLK_FILL_BYTES]; }; static enum State { RESET = 0, READY = 1, SAT = 2, UNSAT = 3, UNKNOWN = 4, } state = RESET; static int last_sat_call_result; static FILE *out; static char * prefix; static int verbosity; static unsigned level; static unsigned max_var; static unsigned size_vars; static Lit * __attribute__((aligned(64))) lits; static Var *vars; static Rnk *rnks; static Flt *jwh; static Cls **htps; #ifndef NDSC static Cls **dhtps; #endif #ifdef NO_BINARY_CLAUSES static Ltk *impls; static Cls impl, cimpl; static int implvalid, cimplvalid; #else static Cls **impls; #endif static Lit **trail, **thead, **eot, **ttail, ** ttail2; #ifndef NADC static Lit **ttailado; #endif static unsigned adecidelevel; static Lit **als, **alshead, **alstail, **eoals; static int *fals, *falshead, *eofals; static int *mass, szmass; static Lit *failed_assumption; static int extracted_all_failed_assumptions; static Rnk **heap, **hhead, **eoh; static Cls **oclauses, **ohead, **eoo; /* original clauses */ static Cls **lclauses, **lhead, ** eol; /* learned clauses */ #ifdef TRACE static int trace; static Zhn **zhains, **zhead, **eoz; static int ocore = -1; #endif static FILE * rup; static int rupstarted; static int rupvariables; static int rupclauses; static Cls *mtcls; static Cls *conflict; static Lit **added, **ahead, **eoa; static Var **marked, **mhead, **eom; static Var **dfs, **dhead, **eod; static Cls **resolved, **rhead, **eor; static unsigned char *buffer, *bhead, *eob; static Act vinc, lscore, ilvinc, ifvinc; #ifdef VISCORES static Act fvinc, nvinc; #endif static Act cinc, lcinc, ilcinc, fcinc; static unsigned srng; static size_t current_bytes; static size_t max_bytes; static size_t recycled; static double seconds; static double entered; static unsigned nentered; static int measurealltimeinlib; static char *rline[2]; static int szrline, rcount; static double levelsum; static unsigned iterations; static int reports; static int lastrheader = -2; static unsigned calls; static unsigned decisions; static unsigned restarts; static unsigned simps; static unsigned fsimplify; static unsigned isimplify; static unsigned reductions; static unsigned lreduce; static unsigned lreduceadjustcnt; static unsigned lreduceadjustinc; static unsigned lastreduceconflicts; static unsigned llocked; /* locked large learned clauses */ static unsigned lrestart; #ifdef NLUBY static unsigned drestart; static unsigned ddrestart; #else static unsigned lubycnt; static unsigned lubymaxdelta; static int waslubymaxdelta; #endif static unsigned long long lsimplify; static unsigned long long propagations; static unsigned long long lpropagations; static unsigned fixed; /* top level assignments */ #ifndef NFL static unsigned failedlits; static unsigned ifailedlits; static unsigned efailedlits; static unsigned flcalls; #ifdef STATS static unsigned flrounds; static unsigned long long flprops; static unsigned long long floopsed, fltried, flskipped; #endif static unsigned long long fllimit; static int simplifying; static Lit ** saved; static unsigned saved_size; #endif static unsigned conflicts; static unsigned noclauses; /* current number large original clauses */ static unsigned nlclauses; /* current number large learned clauses */ static unsigned olits; /* current literals in large original clauses */ static unsigned llits; /* current literals in large learned clauses */ static unsigned oadded; /* added original clauses */ static unsigned ladded; /* added learned clauses */ static unsigned loadded; /* added original large clauses */ static unsigned lladded; /* added learned large clauses */ static unsigned addedclauses; /* oadded + ladded */ static unsigned vused; /* used variables */ static unsigned llitsadded; /* added learned literals */ #ifdef STATS static unsigned loused; /* used large original clauses */ static unsigned llused; /* used large learned clauses */ static unsigned long long visits; static unsigned long long bvisits; static unsigned long long tvisits; static unsigned long long lvisits; static unsigned long long othertrue; static unsigned long long othertrue2; static unsigned long long othertruel; static unsigned long long othertrue2u; static unsigned long long othertruelu; static unsigned long long ltraversals; static unsigned long long traversals; #ifdef TRACE static unsigned long long antecedents; #endif static unsigned uips; static unsigned znts; static unsigned assumptions; static unsigned rdecisions; static unsigned sdecisions; static size_t srecycled; static size_t rrecycled; static unsigned long long derefs; #endif static unsigned minimizedllits; static unsigned nonminimizedllits; #ifndef NADC static Lit *** ados, *** hados, *** eados; static Lit *** adotab; static unsigned nadotab; static unsigned szadotab; static Cls * adoconflict; static unsigned adoconflicts; static unsigned adoconflictlimit = UINT_MAX; static int addingtoado; static int adodisabled; #endif static unsigned long long flips; #ifdef STATS static unsigned long long forced; static unsigned long long assignments; static unsigned inclreduces; static unsigned staticphasedecisions; static unsigned skippedrestarts; #endif static int * indices, * ihead, *eoi; static unsigned sdflips; static int defaultphase; static unsigned long long saved_flips; static unsigned saved_max_var; static unsigned min_flipped = UINT_MAX; static void * emgr; static void * (*enew)(void*,size_t); static void * (*eresize)(void*,void*,size_t,size_t); static void (*edelete)(void*,void*,size_t); #ifdef VISCORES static FILE * fviscores; #endif static Flt packflt (unsigned m, int e) { Flt res; assert (m < FLTMSB); assert (FLTMINEXPONENT <= e); assert (e <= FLTMAXEXPONENT); res = m | ((e + 128) << 24); return res; } static Flt base2flt (unsigned m, int e) { if (!m) return ZEROFLT; if (m < FLTMSB) { do { if (e <= FLTMINEXPONENT) return ZEROFLT; e--; m <<= 1; } while (m < FLTMSB); } else { while (m >= FLTCARRY) { if (e >= FLTMAXEXPONENT) return INFFLT; e++; m >>= 1; } } m &= ~FLTMSB; return packflt (m, e); } static Flt addflt (Flt a, Flt b) { unsigned ma, mb, delta; int ea, eb; cmpswapflt (a, b); if (!b) return a; unpackflt (a, ma, ea); unpackflt (b, mb, eb); assert (ea >= eb); delta = ea - eb; mb >>= delta; if (!mb) return a; ma += mb; if (ma & FLTCARRY) { if (ea == FLTMAXEXPONENT) return INFFLT; ea++; ma >>= 1; } assert (ma < FLTCARRY); ma &= FLTMAXMANTISSA; return packflt (ma, ea); } static Flt mulflt (Flt a, Flt b) { unsigned ma, mb; unsigned long long accu; int ea, eb; cmpswapflt (a, b); if (!b) return ZEROFLT; unpackflt (a, ma, ea); unpackflt (b, mb, eb); ea += eb; ea += 24; if (ea > FLTMAXEXPONENT) return INFFLT; if (ea < FLTMINEXPONENT) return ZEROFLT; accu = ma; accu *= mb; accu >>= 24; if (accu >= FLTCARRY) { if (ea == FLTMAXEXPONENT) return INFFLT; ea++; accu >>= 1; if (accu >= FLTCARRY) return INFFLT; } assert (accu < FLTCARRY); assert (accu & FLTMSB); ma = accu; ma &= ~FLTMSB; return packflt (ma, ea); } static int ISDIGIT (char c) { return '0' <= c && c <= '9'; } static Flt ascii2flt (const char *str) { Flt ten = base2flt (10, 0); Flt onetenth = base2flt (26843546, -28); Flt res = ZEROFLT, tmp, base; const char *p = str; char ch; ch = *p++; if (ch != '.') { if (!ISDIGIT (ch)) return INFFLT; /* better abort ? */ res = base2flt (ch - '0', 0); while ((ch = *p++)) { if (ch == '.') break; if (!ISDIGIT (ch)) return INFFLT; /* better abort? */ res = mulflt (res, ten); tmp = base2flt (ch - '0', 0); res = addflt (res, tmp); } } if (ch == '.') { ch = *p++; if (!ISDIGIT (ch)) return INFFLT; /* better abort ? */ base = onetenth; tmp = mulflt (base2flt (ch - '0', 0), base); res = addflt (res, tmp); while ((ch = *p++)) { if (!ISDIGIT (ch)) return INFFLT; /* better abort? */ base = mulflt (base, onetenth); tmp = mulflt (base2flt (ch - '0', 0), base); res = addflt (res, tmp); } } return res; } #if defined(VISCORES) static double flt2double (Flt f) { double res; unsigned m; int e, i; unpackflt (f, m, e); res = m; if (e < 0) { for (i = e; i < 0; i++) res *= 0.5; } else { for (i = 0; i < e; i++) res *= 2.0; } return res; } #endif static int log2flt (Flt a) { return FLTEXPONENT (a) + 24; } static int cmpflt (Flt a, Flt b) { if (a < b) return -1; if (a > b) return 1; return 0; } static void * new (size_t size) { size_t bytes; Blk *b; if (!size) return 0; bytes = size + SIZE_OF_BLK; if (enew) b = enew (emgr, bytes); else b = malloc (bytes); ABORTIF (!b, "out of memory in 'new'"); #ifndef NDEBUG b->header.size = size; #endif current_bytes += size; if (current_bytes > max_bytes) max_bytes = current_bytes; return b->data; } static void delete (void *void_ptr, size_t size) { size_t bytes; Blk *b; if (!void_ptr) { assert (!size); return; } assert (size); b = PTR2BLK (void_ptr); assert (size <= current_bytes); current_bytes -= size; assert (b->header.size == size); bytes = size + SIZE_OF_BLK; if (edelete) edelete (emgr, b, bytes); else free (b); } static void * resize (void *void_ptr, size_t old_size, size_t new_size) { size_t old_bytes, new_bytes; Blk *b; b = PTR2BLK (void_ptr); assert (old_size <= current_bytes); current_bytes -= old_size; if ((old_bytes = old_size)) { assert (old_size && b->header.size == old_size); old_bytes += SIZE_OF_BLK; } else assert (!b); if ((new_bytes = new_size)) new_bytes += SIZE_OF_BLK; if (eresize) b = eresize (emgr, b, old_bytes, new_bytes); else b = realloc (b, new_bytes); if (!new_size) { assert (!b); return 0; } ABORTIF (!b, "out of memory in 'resize'"); #ifndef NDEBUG b->header.size = new_size; #endif current_bytes += new_size; if (current_bytes > max_bytes) max_bytes = current_bytes; return b->data; } static unsigned int2unsigned (int l) { return (l < 0) ? 1 + 2 * -l : 2 * l; } static Lit * int2lit (int l) { return lits + int2unsigned (l); } static Lit ** end_of_lits (Cls * cls) { return cls->lits + cls->size; } static int lit2idx (Lit * lit) { return (lit - lits) / 2; } static int lit2sign (Lit * lit) { return ((lit - lits) & 1) ? -1 : 1; } static int lit2int (Lit * l) { return lit2idx (l) * lit2sign (l); } #if !defined(NDEBUG) || defined(LOGGING) static void dumplits (Lit ** lits, Lit ** eol) { int first; Lit ** p; if (lits == eol) { /* empty clause */ } else if (lits + 1 == eol) { fprintf (out, "%d ", lit2int (lits[0])); } else { assert (lits + 2 <= eol); first = (abs (lit2int (lits[0])) > abs (lit2int (lits[1]))); fprintf (out, "%d ", lit2int (lits[first])); fprintf (out, "%d ", lit2int (lits[!first])); for (p = lits + 2; p < eol; p++) fprintf (out, "%d ", lit2int (*p)); } fputc ('0', out); } static void dumpcls (Cls * cls) { Lit **eol; if (cls) { eol = end_of_lits (cls); dumplits (cls->lits, eol); #ifdef TRACE if (trace) fprintf (out, " clause(%u)", CLS2IDX (cls)); #endif } else fputs ("DECISION", out); } static void dumpclsnl (Cls * cls) { dumpcls (cls); fputc ('\n', out); } void dumpcnf (void) { Cls **p, *cls; for (p = SOC; p != EOC; p = NXC (p)) { cls = *p; if (!cls) continue; #ifdef TRACE if (cls->collected) continue; #endif dumpclsnl (*p); } } #endif static void delete_prefix (void) { if (!prefix) return; delete (prefix, strlen (prefix) + 1); prefix = 0; } static void new_prefix (const char * str) { delete_prefix (); assert (str); prefix = new (strlen (str) + 1); strcpy (prefix, str); } static void init (void) { static int count; ABORTIF (state != RESET, "API usage: multiple initializations"); count = 3 - !enew - !eresize - !edelete; ABORTIF (count && !enew, "API usage: missing 'picosat_set_new'"); ABORTIF (count && !eresize, "API usage: missing 'picosat_set_resize'"); ABORTIF (count && !edelete, "API usage: missing 'picosat_set_delete'"); assert (!max_var); /* check for proper reset */ assert (!size_vars); /* check for proper reset */ size_vars = 1; NEWN (lits, 2 * size_vars); NEWN (jwh, 2 * size_vars); NEWN (htps, 2 * size_vars); #ifndef NDSC NEWN (dhtps, 2 * size_vars); #endif NEWN (impls, 2 * size_vars); NEWN (vars, size_vars); NEWN (rnks, size_vars); ENLARGE (heap, hhead, eoh); /* because '0' pos denotes not on heap */ hhead = heap + 1; vinc = base2flt (1, 0); /* initial variable activity */ ifvinc = ascii2flt ("1.05"); /* variable score rescore factor */ #ifdef VISCORES fvinc = ascii2flt ("0.9523809"); /* 1/f = 1/1.1 */ nvinc = ascii2flt ("0.0476191"); /* 1 - 1/f = 1 - 1/1.1 */ #endif lscore = base2flt (1, 90); /* variable activity rescore limit */ ilvinc = base2flt (1, -90); /* inverse of 'lscore' */ cinc = base2flt (1, 0); /* initial clause activity */ fcinc = ascii2flt ("1.001"); /* clause activity rescore factor */ lcinc = base2flt (1, 90); /* clause activity rescore limit */ ilcinc = base2flt (1, -90); /* inverse of 'ilcinc' */ lreduceadjustcnt = lreduceadjustinc = 100; lpropagations = ~0ull; out = stdout; new_prefix ("c "); verbosity = 0; #ifdef NO_BINARY_CLAUSES memset (&impl, 0, sizeof (impl)); impl.size = 2; memset (&cimpl, 0, sizeof (impl)); cimpl.size = 2; #endif #ifdef VISCORES fviscores = popen ( "/usr/bin/gnuplot -background black" " -xrm 'gnuplot*textColor:white'" " -xrm 'gnuplot*borderColor:white'" " -xrm 'gnuplot*axisColor:white'" , "w"); fprintf (fviscores, "unset key\n"); // fprintf (fviscores, "set log y\n"); fflush (fviscores); system ("rm -rf /tmp/picosat-viscores"); system ("mkdir /tmp/picosat-viscores"); system ("mkdir /tmp/picosat-viscores/data"); #ifdef WRITEGIF system ("mkdir /tmp/picosat-viscores/gif"); fprintf (fviscores, "set terminal gif giant animate opt size 1024,768 x000000 xffffff" "\n"); fprintf (fviscores, "set output \"/tmp/picosat-viscores/gif/animated.gif\"\n"); #endif #endif defaultphase = 2; state = READY; last_sat_call_result = 0; } static size_t bytes_clause (unsigned size, unsigned learned) { size_t res; res = sizeof (Cls); res += size * sizeof (Lit *); res -= 2 * sizeof (Lit *); if (learned && size > 2) res += sizeof (Act); /* add activity */ #ifdef TRACE if (trace) res += sizeof (Trd); /* add trace data */ #endif return res; } static Cls * new_clause (unsigned size, unsigned learned) { size_t bytes; void * tmp; #ifdef TRACE Trd *trd; #endif Cls *res; bytes = bytes_clause (size, learned); tmp = new (bytes); #ifdef TRACE if (trace) { trd = tmp; if (learned) trd->idx = LIDX2IDX (lhead - lclauses); else trd->idx = OIDX2IDX (ohead - oclauses); res = trd->cls; } else #endif res = tmp; res->size = size; res->learned = learned; res->collect = 0; #ifndef NDEBUG res->connected = 0; #endif res->locked = 0; res->fixed = 0; res->used = 0; #ifdef TRACE res->core = 0; #ifndef NDEBUG res->collected = 0; #endif #endif if (learned && size > 2) *CLS2ACT (res) = cinc; return res; } static void delete_clause (Cls * cls) { size_t bytes; #ifdef TRACE Trd *trd; #endif bytes = bytes_clause (cls->size, cls->learned); #ifdef TRACE if (trace) { trd = CLS2TRD (cls); delete (trd, bytes); } else #endif delete (cls, bytes); } static void delete_clauses (void) { Cls **p; for (p = SOC; p != EOC; p = NXC (p)) if (*p) delete_clause (*p); DELETEN (oclauses, eoo - oclauses); DELETEN (lclauses, eol - lclauses); ohead = eoo = lhead = eol = 0; } #ifdef TRACE static void delete_zhain (Zhn * zhain) { const Znt *p, *znt; assert (zhain); znt = zhain->znt; for (p = znt; *p; p++) ; delete (zhain, sizeof (Zhn) + (p - znt) + 1); } static void delete_zhains (void) { Zhn **p, *z; for (p = zhains; p < zhead; p++) if ((z = *p)) delete_zhain (z); DELETEN (zhains, eoz - zhains); eoz = zhead = 0; } #endif #ifdef NO_BINARY_CLAUSES static void lrelease (Ltk * stk) { if (stk->start) DELETEN (stk->start, (1 << (stk->ldsize))); memset (stk, 0, sizeof (*stk)); } #endif #ifndef NADC static unsigned llength (Lit ** a) { Lit ** p; for (p = a; *p; p++) ; return p - a; } static void resetadoconflict (void) { assert (adoconflict); delete_clause (adoconflict); adoconflict = 0; } static void reset_ados (void) { Lit *** p; for (p = ados; p < hados; p++) DELETEN (*p, llength (*p) + 1); DELETEN (ados, eados - ados); hados = eados = 0; DELETEN (adotab, szadotab); szadotab = nadotab = 0; if (adoconflict) resetadoconflict (); adoconflicts = 0; adoconflictlimit = UINT_MAX; adodisabled = 0; } #endif static void reset (void) { ABORTIF (state == RESET, "API usage: reset without initialization"); delete_clauses (); #ifdef TRACE delete_zhains (); #endif #ifdef NO_BINARY_CLAUSES implvalid = 0; cimplvalid = 0; { unsigned i; for (i = 2; i <= 2 * max_var + 1; i++) lrelease (impls + i); } #endif #ifndef NADC reset_ados (); #endif #ifndef NFL DELETEN (saved, saved_size); saved_size = 0; #endif DELETEN (htps, 2 * size_vars); #ifndef NDSC DELETEN (dhtps, 2 * size_vars); #endif DELETEN (impls, 2 * size_vars); DELETEN (lits, 2 * size_vars); DELETEN (jwh, 2 * size_vars); DELETEN (vars, size_vars); DELETEN (rnks, size_vars); DELETEN (trail, eot - trail); trail = ttail = ttail2 = thead = eot = 0; #ifndef NADC ttailado = 0; #endif DELETEN (heap, eoh - heap); heap = hhead = eoh = 0; DELETEN (als, eoals - als); als = eoals = alshead = alstail = 0; extracted_all_failed_assumptions = 0; failed_assumption = 0; adecidelevel = 0; DELETEN (fals, eofals - fals); fals = eofals = falshead = 0; DELETEN (mass, szmass); szmass = 0; mass = 0; size_vars = 0; max_var = 0; mtcls = 0; #ifdef TRACE ocore = -1; #endif conflict = 0; DELETEN (added, eoa - added); eoa = ahead = 0; DELETEN (marked, eom - marked); eom = mhead = 0; DELETEN (dfs, eod - dfs); eod = dhead = 0; DELETEN (resolved, eor - resolved); eor = rhead = 0; DELETEN (buffer, eob - buffer); eob = bhead = 0; DELETEN (indices, eoi - indices); eoi = ihead = 0; delete_prefix (); delete (rline[0], szrline); delete (rline[1], szrline); rline[0] = rline[1] = 0; szrline = rcount = 0; assert (getenv ("LEAK") || !current_bytes); /* found leak if failing */ max_bytes = 0; recycled = 0; current_bytes = 0; lrestart = 0; lreduce = 0; lastreduceconflicts = 0; llocked = 0; lsimplify = 0; fsimplify = 0; seconds = 0; entered = 0; nentered = 0; measurealltimeinlib = 0; levelsum = 0.0; calls = 0; decisions = 0; restarts = 0; simps = 0; iterations = 0; reports = 0; lastrheader = -2; fixed = 0; #ifndef NFL failedlits = 0; simplifying = 0; fllimit = 0; #ifdef STATS efailedlits = ifailedlits = 0; fltried = flskipped = floopsed = 0; flcalls = flrounds = 0; flprops = 0; #endif #endif propagations = 0; conflicts = 0; noclauses = 0; oadded = 0; lladded = 0; loadded = 0; olits = 0; nlclauses = 0; ladded = 0; addedclauses = 0; llits = 0; out = 0; #ifdef TRACE trace = 0; #endif rup = 0; rupstarted = 0; rupclauses = 0; rupvariables = 0; level = 0; reductions = 0; vused = 0; llitsadded = 0; #ifdef STATS loused = 0; llused = 0; visits = 0; bvisits = 0; tvisits = 0; lvisits = 0; othertrue = 0; othertrue2 = 0; othertruel = 0; othertrue2u = 0; othertruelu = 0; ltraversals = 0; traversals = 0; #ifndef NO_BINARY_CLAUSES antecedents = 0; #endif znts = 0; uips = 0; assumptions = 0; rdecisions = 0; sdecisions = 0; srecycled = 0; rrecycled = 0; #endif minimizedllits = 0; nonminimizedllits = 0; state = RESET; srng = 0; saved_flips = 0; saved_max_var = 0; min_flipped = UINT_MAX; flips = 0; #ifdef STATS forced = 0; assignments = 0; #endif sdflips = 0; defaultphase = 2; #ifdef STATS staticphasedecisions = 0; inclreduces = 0; skippedrestarts = 0; #endif emgr = 0; enew = 0; eresize = 0; edelete = 0; #ifdef VISCORES pclose (fviscores); fviscores = 0; #endif } inline static void tpush (Lit * lit) { assert (lits < lit && lit <= lits + 2* max_var + 1); if (thead == eot) { unsigned ttail2count = ttail2 - trail; unsigned ttailcount = ttail - trail; #ifndef NADC unsigned ttailadocount = ttailado - trail; #endif ENLARGE (trail, thead, eot); ttail = trail + ttailcount; ttail2 = trail + ttail2count; #ifndef NADC ttailado = trail + ttailadocount; #endif } *thead++ = lit; } static void assign_reason (Var * v, Cls * reason) { #ifdef NO_BINARY_CLAUSES assert (reason != &impl); #endif v->reason = reason; } static void assign_phase (Lit * lit) { unsigned new_phase, idx; Var * v = LIT2VAR (lit); #ifndef NFL /* In 'simplifying' mode we only need to keep 'min_flipped' up to date if * we force assignments on the top level. The other assignments will be * undone and thus we can keep the old saved value of the phase. */ if (!level || !simplifying) #endif { new_phase = (LIT2SGN (lit) > 0); if (v->assigned) { sdflips -= sdflips/FFLIPPED; if (new_phase != v->phase) { assert (FFLIPPEDPREC >= FFLIPPED); sdflips += FFLIPPEDPREC / FFLIPPED; flips++; idx = lit2idx (lit); if (idx < min_flipped) min_flipped = idx; NOLOG (fprintf (out, "%sflipped %d\n", prefix, lit2int (lit))); } } v->phase = new_phase; v->assigned = 1; } lit->val = TRUE; NOTLIT (lit)->val = FALSE; } inline static void assign (Lit * lit, Cls * reason) { Var * v = LIT2VAR (lit); assert (lit->val == UNDEF); #ifdef STATS assignments++; #endif v->level = level; assign_phase (lit); assign_reason (v, reason); tpush (lit); } inline static int cmp_added (Lit * k, Lit * l) { Val a = k->val, b = l->val; Var *u, *v; int res; if (a == UNDEF && b != UNDEF) return -1; if (a != UNDEF && b == UNDEF) return 1; u = LIT2VAR (k); v = LIT2VAR (l); if (a != UNDEF) { assert (b != UNDEF); res = v->level - u->level; if (res) return res; /* larger level first */ } res = cmpflt (VAR2RNK (v)->score, VAR2RNK (u)->score); if (res) return res; /* larger activity first */ return u - v; /* smaller index first */ } static void sorttwolits (Lit ** v) { Lit * a = v[0], * b = v[1]; assert (a != b); if (a < b) return; v[0] = b; v[1] = a; } inline static void sortlits (Lit ** v, unsigned size) { if (size == 2) sorttwolits (v); /* same order with and with out 'NO_BINARY_CLAUSES' */ else sort (Lit *, cmp_added, v, size); } #ifdef NO_BINARY_CLAUSES static Cls * setimpl (Lit * a, Lit * b) { assert (!implvalid); assert (impl.size == 2); impl.lits[0] = a; impl.lits[1] = b; sorttwolits (impl.lits); implvalid = 1; return &impl; } static void resetimpl (void) { assert (implvalid); implvalid = 0; } static Cls * setcimpl (Lit * a, Lit * b) { assert (!cimplvalid); assert (cimpl.size == 2); cimpl.lits[0] = a; cimpl.lits[1] = b; sorttwolits (cimpl.lits); cimplvalid = 1; return &cimpl; } static void resetcimpl (void) { assert (cimplvalid); cimplvalid = 0; } #endif static int cmp_ptr (void *l, void *k) { return ((char*)l) - (char*)k; /* arbitrarily already reverse */ } static int cmp_rnk (Rnk * r, Rnk * s) { if (!r->moreimportant && s->moreimportant) return -1; if (r->moreimportant && !s->moreimportant) return 1; if (!r->lessimportant && s->lessimportant) return 1; if (r->lessimportant && !s->lessimportant) return -1; if (r->score < s->score) return -1; if (r->score > s->score) return 1; return -cmp_ptr (r, s); } static void hup (Rnk * v) { int upos, vpos; Rnk *u; #ifndef NFL assert (!simplifying); #endif vpos = v->pos; assert (0 < vpos); assert (vpos < hhead - heap); assert (heap[vpos] == v); while (vpos > 1) { upos = vpos / 2; u = heap[upos]; if (cmp_rnk (u, v) > 0) break; heap[vpos] = u; u->pos = vpos; vpos = upos; } heap[vpos] = v; v->pos = vpos; } static Cls *add_simplified_clause (int learned); inline static void add_antecedent (Cls * c) { assert (c); #ifdef NO_BINARY_CLAUSES if (ISLITREASON (c)) return; if (c == &impl) return; #else #ifdef STATS antecedents++; #endif #endif if (rhead == eor) ENLARGE (resolved, rhead, eor); assert (rhead < eor); *rhead++ = c; } #ifdef TRACE #ifdef NO_BINARY_CLAUSES #error "can not combine TRACE and NO_BINARY_CLAUSES" #endif #endif /* TRACE */ static void add_lit (Lit * lit) { assert (lit); if (ahead == eoa) ENLARGE (added, ahead, eoa); *ahead++ = lit; } static void push_var_as_marked (Var * v) { if (mhead == eom) ENLARGE (marked, mhead, eom); *mhead++ = v; } static void mark_var (Var * v) { assert (!v->mark); v->mark = 1; push_var_as_marked (v); } /* Whenever we have a top level derived unit we really should derive a unit * clause otherwise the resolutions in 'add_simplified_clause' become * incorrect. */ static Cls * resolve_top_level_unit (Lit * lit, Cls * reason) { unsigned count_resolved; Lit **p, **eol, *other; Var *u, *v; assert (rhead == resolved); assert (ahead == added); add_lit (lit); add_antecedent (reason); count_resolved = 1; v = LIT2VAR (lit); eol = end_of_lits (reason); for (p = reason->lits; p < eol; p++) { other = *p; u = LIT2VAR (other); if (u == v) continue; add_antecedent (u->reason); count_resolved++; } /* Some of the literals could be assumptions. If at least one * variable is not an assumption, we should resolve. */ if (count_resolved >= 2) { #ifdef NO_BINARY_CLAUSES if (reason == &impl) resetimpl (); #endif reason = add_simplified_clause (1); #ifdef NO_BINARY_CLAUSES if (reason->size == 2) { assert (reason == &impl); other = reason->lits[0]; if (lit == other) other = reason->lits[1]; assert (other->val == FALSE); reason = LIT2REASON (NOTLIT (other)); resetimpl (); } #endif assign_reason (v, reason); } else { ahead = added; rhead = resolved; } return reason; } static void fixvar (Var * v) { Rnk * r; assert (VAR2LIT (v) != UNDEF); assert (!v->level); fixed++; r = VAR2RNK (v); r->score = INFFLT; #ifndef NFL if (simplifying) return; #endif if (!r->pos) return; hup (r); } static void use_var (Var * v) { if (v->used) return; v->used = 1; vused++; } static void assign_forced (Lit * lit, Cls * reason) { Var *v; assert (reason); assert (lit->val == UNDEF); #ifdef STATS forced++; #endif assign (lit, reason); #ifdef NO_BINARY_CLAUSES assert (reason != &impl); if (ISLITREASON (reason)) reason = setimpl (lit, NOTLIT (REASON2LIT (reason))); #endif LOG (fprintf (out, "%sassign %d at level %d by ", prefix, lit2int (lit), level); dumpclsnl (reason)); v = LIT2VAR (lit); if (!level) use_var (v); if (reason && !level && reason->size > 1) reason = resolve_top_level_unit (lit, reason); #ifdef NO_BINARY_CLAUSES if (ISLITREASON (reason) || reason == &impl) { /* DO NOTHING */ } else #endif if (reason) { assert (!reason->locked); reason->locked = 1; if (reason->learned && reason->size > 2) llocked++; } #ifdef NO_BINARY_CLAUSES if (reason == &impl) resetimpl (); #endif if (!level) fixvar (v); } #ifdef NO_BINARY_CLAUSES static void lpush (Lit * lit, Cls * cls) { int pos = (cls->lits[0] == lit); Ltk * s = LIT2IMPLS (lit); unsigned oldsize, newsize; assert (cls->size == 2); if (!s->start) { assert (!s->count); assert (!s->ldsize); NEWN (s->start, 1); } else { oldsize = (1 << (s->ldsize)); assert (s->count <= oldsize); if (s->count == oldsize) { newsize = 2 * oldsize; RESIZEN (s->start, oldsize, newsize); s->ldsize++; } } s->start[s->count++] = cls->lits[pos]; } #endif static void connect_head_tail (Lit * lit, Cls * cls) { Cls ** s; assert (cls->size >= 1); if (cls->size == 2) { #ifdef NO_BINARY_CLAUSES lpush (lit, cls); return; #else s = LIT2IMPLS (lit); #endif } else s = LIT2HTPS (lit); if (cls->lits[0] != lit) { assert (cls->size >= 2); assert (cls->lits[1] == lit); cls->next[1] = *s; } else cls->next[0] = *s; *s = cls; } #ifdef TRACE static void zpush (Zhn * zhain) { assert (trace); if (zhead == eoz) ENLARGE (zhains, zhead, eoz); *zhead++ = zhain; } static int cmp_resolved (Cls * c, Cls * d) { assert (trace); return CLS2IDX (c) - CLS2IDX (d); } static void bpushc (unsigned char ch) { if (bhead == eob) ENLARGE (buffer, bhead, eob); *bhead++ = ch; } static void bpushu (unsigned u) { while (u & ~0x7f) { bpushc (u | 0x80); u >>= 7; } bpushc (u); } static void bpushd (unsigned prev, unsigned this) { unsigned delta; assert (prev < this); delta = this - prev; bpushu (delta); } static void add_zhain (void) { unsigned prev, this, count, rcount; Cls **p, *c; Zhn *res; assert (trace); assert (bhead == buffer); assert (rhead > resolved); rcount = rhead - resolved; sort (Cls *, cmp_resolved, resolved, rcount); prev = 0; for (p = resolved; p < rhead; p++) { c = *p; this = CLS2TRD (c)->idx; bpushd (prev, this); prev = this; } bpushc (0); count = bhead - buffer; res = new (sizeof (Zhn) + count); res->core = 0; res->ref = 0; memcpy (res->znt, buffer, count); bhead = buffer; #ifdef STATS znts += count - 1; #endif zpush (res); } #endif static void add_resolved (int learned) { #if defined(STATS) || defined(TRACE) Cls **p, *c; for (p = resolved; p < rhead; p++) { c = *p; if (c->used) continue; c->used = 1; if (c->size <= 2) continue; #ifdef STATS if (c->learned) llused++; else loused++; #endif } #endif #ifdef TRACE if (learned && trace) add_zhain (); #else (void) learned; #endif rhead = resolved; } static void incjwh (Cls * cls) { Lit **p, *lit, ** eol; Flt * f, inc, sum; unsigned size = 0; Var * v; Val val; eol = end_of_lits (cls); for (p = cls->lits; p < eol; p++) { lit = *p; val = lit->val; if (val && level > 0) { v = LIT2VAR (lit); if (v->level > 0) val = UNDEF; } if (val == TRUE) return; if (val != FALSE) size++; } inc = base2flt (1, -size); for (p = cls->lits; p < eol; p++) { lit = *p; f = LIT2JWH (lit); sum = addflt (*f, inc); *f = sum; } } static void write_rup_header (FILE * file) { char line[80]; int i; sprintf (line, "%%RUPD32 %u %u", rupvariables, rupclauses); fputs (line, file); for (i = 255 - strlen (line); i >= 0; i--) fputc (' ', file); fputc ('\n', file); fflush (file); } static void write_int (int d, FILE * file) { static char write_int_buffer[16]; unsigned tmp; char * res; int sign; assert (sizeof d <= 4); res = write_int_buffer + sizeof write_int_buffer; *--res = 0; sign = (d < 0); if (sign) tmp = (unsigned) -d; else tmp = d; do { assert (res > write_int_buffer); *--res = '0' + (tmp % 10); tmp /= 10; } while (tmp); if (sign) { assert (res > write_int_buffer); *--res = '-'; } fputs (res, file); } static Cls * add_simplified_clause (int learned) { unsigned num_true, num_undef, num_false, idx, size, count_resolved; Lit **p, **q, *lit, ** end; Cls *res, * reason; Val val; Var *v; REENTER: size = ahead - added; add_resolved (learned); if (learned) { ladded++; llitsadded += size; if (size > 2) { lladded++; nlclauses++; llits += size; } } else { oadded++; if (size > 2) { loadded++; noclauses++; olits += size; } } addedclauses++; assert (addedclauses == ladded + oadded); #ifdef NO_BINARY_CLAUSES if (size == 2) res = setimpl (added[0], added[1]); else #endif { sortlits (added, size); if (learned) { if (lhead == eol) { ENLARGE (lclauses, lhead, eol); /* A very difficult to find bug, which only occurs if the * learned clauses stack is immediately allocated before the * original clauses stack without padding. In this case, we * have 'SOC == EOC', which terminates all loops using the * idiom 'for (p = SOC; p != EOC; p = NXC(p))' immediately. * Unfortunately this occurred in 'fix_clause_lits' after * using a recent version of the memory allocator of 'Google' * perftools in the context of one large benchmark for * 'boolector'. */ if (eol == oclauses) ENLARGE (lclauses, lhead, eol); } idx = LIDX2IDX (lhead - lclauses); } else { if (ohead == eoo) { ENLARGE (oclauses, ohead, eoo); if (eol == oclauses) ENLARGE (oclauses, ohead, eoo); /* dito */ } idx = OIDX2IDX (ohead - oclauses); } assert (eol != oclauses); /* dito */ res = new_clause (size, learned); #if !defined(NDEBUG) && defined(TRACE) if (trace) assert (CLS2IDX (res) == idx); #endif if (learned) *lhead++ = res; else *ohead++ = res; #if !defined(NDEBUG) && defined(TRACE) if (trace && learned) assert (zhead - zhains == lhead - lclauses); #endif assert (lhead != oclauses); /* dito */ } if (learned && rup) { if (!rupstarted) { write_rup_header (rup); rupstarted = 1; } } num_true = num_undef = num_false = 0; q = res->lits; for (p = added; p < ahead; p++) { lit = *p; *q++ = lit; if (learned && rup) { write_int (lit2int (lit), rup); fputc (' ', rup); } val = lit->val; num_true += (val == TRUE); num_undef += (val == UNDEF); num_false += (val == FALSE); v = LIT2VAR (lit); } assert (num_false + num_true + num_undef == size); if (learned && rup) fputs ("0\n", rup); ahead = added; /* reset */ if (size > 0) { connect_head_tail (res->lits[0], res); if (size > 1) connect_head_tail (res->lits[1], res); } if (size == 0) { if (!mtcls) mtcls = res; } #ifdef NO_BINARY_CLAUSES if (size != 2) #endif #ifndef NDEBUG res->connected = 1; #endif LOG (fprintf (out, "%s%s ", prefix, learned ? "learned" : "original"); dumpclsnl (res)); /* Shrink clause by resolving it against top level assignments. */ if (!level && num_false > 0) { assert (ahead == added); assert (rhead == resolved); count_resolved = 1; add_antecedent (res); end = end_of_lits (res); for (p = res->lits; p < end; p++) { lit = *p; v = LIT2VAR (lit); use_var (v); if (lit->val == FALSE) { add_antecedent (v->reason); count_resolved++; } else add_lit (lit); } assert (count_resolved >= 2); learned = 1; #ifdef NO_BINARY_CLAUSES if (res == &impl) resetimpl (); #endif goto REENTER; /* and return simplified clause */ } if (!num_true && num_undef == 1) /* unit clause */ { lit = 0; for (p = res->lits; p < res->lits + size; p++) { if ((*p)->val == UNDEF) lit = *p; v = LIT2VAR (*p); use_var (v); } assert (lit); reason = res; #ifdef NO_BINARY_CLAUSES if (size == 2) { Lit * other = res->lits[0]; if (other == lit) other = res->lits[1]; assert (other->val == FALSE); reason = LIT2REASON (NOTLIT (other)); } #endif assign_forced (lit, reason); num_true++; } if (num_false == size && !conflict) { #ifdef NO_BINARY_CLAUSES if (res == &impl) conflict = setcimpl (res->lits[0], res->lits[1]); else #endif conflict = res; } if (!learned && !num_true && num_undef) incjwh (res); //FIXME: perhaps sketchy unsound hack /* #ifdef NO_BINARY_CLAUSES */ /* if (res == &impl) */ /* resetimpl (); */ /* #endif */ return res; } static int trivial_clause (void) { Lit **p, **q, *prev; Var *v; sort (Lit *, cmp_ptr, added, ahead - added); prev = 0; q = added; for (p = q; p < ahead; p++) { Lit *this = *p; v = LIT2VAR (this); if (prev == this) /* skip repeated literals */ continue; /* Top level satisfied ? */ if (this->val == TRUE && !v->level) return 1; if (prev == NOTLIT (this))/* found pair of dual literals */ return 1; *q++ = prev = this; } ahead = q; /* shrink */ return 0; } static void simplify_and_add_original_clause (void) { Cls * cls; if (trivial_clause ()) { ahead = added; if (ohead == eoo) ENLARGE (oclauses, ohead, eoo); *ohead++ = 0; addedclauses++; oadded++; } else { cls = add_simplified_clause (0); #ifdef NO_BINARY_CLAUSES if (cls == &impl) resetimpl (); #endif } } #ifndef NADC static void add_ado (void) { unsigned len = ahead - added; Lit ** ado, ** p, ** q, *lit; Var * v, * u; #ifdef TRACE assert (!trace); #endif ABORTIF (ados < hados && llength (ados[0]) != len, "internal: non matching all different constraint object lengths"); if (hados == eados) ENLARGE (ados, hados, eados); NEWN (ado, len + 1); *hados++ = ado; p = added; q = ado; u = 0; while (p < ahead) { lit = *p++; v = LIT2VAR (lit); ABORTIF (v->inado, "internal: variable in multiple all different objects"); v->inado = ado; if (!u && !lit->val) u = v; *q++ = lit; } assert (q == ado + len); *q++ = 0; /* TODO simply do a conflict test as in propado */ ABORTIF (!u, "internal: " "adding fully instantiated all different object not implemented yet"); assert (u); assert (u->inado == ado); assert (!u->ado); u->ado = ado; ahead = added; } #endif static void hdown (Rnk * r) { unsigned end, rpos, cpos, opos; Rnk *child, *other; assert (r->pos > 0); assert (heap[r->pos] == r); end = hhead - heap; rpos = r->pos; for (;;) { cpos = 2 * rpos; if (cpos >= end) break; opos = cpos + 1; child = heap[cpos]; if (cmp_rnk (r, child) < 0) { if (opos < end) { other = heap[opos]; if (cmp_rnk (child, other) < 0) { child = other; cpos = opos; } } } else if (opos < end) { child = heap[opos]; if (cmp_rnk (r, child) >= 0) break; cpos = opos; } else break; heap[rpos] = child; child->pos = rpos; rpos = cpos; } r->pos = rpos; heap[rpos] = r; } static Rnk * htop (void) { assert (hhead > heap); return heap[1]; } static Rnk * hpop (void) { Rnk *res, *last; unsigned end; assert (hhead > heap); res = heap[1]; res->pos = 0; end = --hhead - heap; if (end == 1) return res; last = heap[end]; heap[last->pos = 1] = last; hdown (last); return res; } inline static void hpush (Rnk * r) { assert (!r->pos); if (hhead == eoh) ENLARGE (heap, hhead, eoh); r->pos = hhead++ - heap; heap[r->pos] = r; hup (r); } static void fix_trail_lits (long delta) { Lit **p; for (p = trail; p < thead; p++) *p += delta; } #ifdef NO_BINARY_CLAUSES static void fix_impl_lits (long delta) { Ltk * s; Lit ** p; for (s = impls + 2; s < impls + 2 * max_var; s++) for (p = s->start; p < s->start + s->count; p++) *p += delta; } #endif static void fix_clause_lits (long delta) { Cls **p, *clause; Lit **q, *lit, **eol; for (p = SOC; p != EOC; p = NXC (p)) { clause = *p; if (!clause) continue; q = clause->lits; eol = end_of_lits (clause); while (q < eol) { assert (q - clause->lits <= (int) clause->size); lit = *q; lit += delta; *q++ = lit; } } } static void fix_added_lits (long delta) { Lit **p; for (p = added; p < ahead; p++) *p += delta; } static void fix_assumed_lits (long delta) { Lit **p; for (p = als; p < alshead; p++) *p += delta; } static void fix_heap_rnks (long delta) { Rnk **p; for (p = heap + 1; p < hhead; p++) *p += delta; } #ifndef NADC static void fix_ado (long delta, Lit ** ado) { Lit ** p; for (p = ado; *p; p++) *p += delta; } static void fix_ados (long delta) { Lit *** p; for (p = ados; p < hados; p++) fix_ado (delta, *p); } #endif static void enlarge (unsigned new_size_vars) { long rnks_delta, lits_delta, vars_delta; Lit *old_lits = lits; Rnk *old_rnks = rnks; Var *old_vars = vars; RESIZEN (lits, 2 * size_vars, 2 * new_size_vars); RESIZEN (jwh, 2 * size_vars, 2 * new_size_vars); RESIZEN (htps, 2 * size_vars, 2 * new_size_vars); #ifndef NDSC RESIZEN (dhtps, 2 * size_vars, 2 * new_size_vars); #endif RESIZEN (impls, 2 * size_vars, 2 * new_size_vars); RESIZEN (vars, size_vars, new_size_vars); RESIZEN (rnks, size_vars, new_size_vars); lits_delta = lits - old_lits; rnks_delta = rnks - old_rnks; vars_delta = vars - old_vars; fix_trail_lits (lits_delta); fix_clause_lits (lits_delta); fix_added_lits (lits_delta); fix_assumed_lits (lits_delta); #ifdef NO_BINARY_CLAUSES fix_impl_lits (lits_delta); #endif #ifndef NADC fix_ados (lits_delta); #endif fix_heap_rnks (rnks_delta); assert (mhead == marked); size_vars = new_size_vars; } static void unassign (Lit * lit) { Cls *reason; Var *v; Rnk *r; assert (lit->val == TRUE); LOG (fprintf (out, "%sunassign %d\n", prefix, lit2int (lit))); v = LIT2VAR (lit); reason = v->reason; #ifdef NO_BINARY_CLAUSES assert (reason != &impl); if (ISLITREASON (reason)) { /* DO NOTHING */ } else #endif if (reason) { assert (reason->locked); reason->locked = 0; if (reason->learned && reason->size > 2) { assert (llocked > 0); llocked--; } } lit->val = UNDEF; NOTLIT (lit)->val = UNDEF; r = VAR2RNK (v); if (!r->pos) hpush (r); #ifndef NDSC { Cls * p, * next, ** q; q = LIT2DHTPS (lit); p = *q; *q = 0; while (p) { Lit * other = p->lits[0]; if (other == lit) { other = p->lits[1]; q = p->next + 1; } else { assert (p->lits[1] == lit); q = p->next; } next = *q; *q = *LIT2HTPS (other); *LIT2HTPS (other) = p; p = next; } } #endif #ifndef NADC if (v->adotabpos) { assert (nadotab); assert (*v->adotabpos == v->ado); *v->adotabpos = 0; v->adotabpos = 0; nadotab--; } #endif } static Cls * var2reason (Var * var) { Cls * res = var->reason; #ifdef NO_BINARY_CLAUSES Lit * this, * other; if (ISLITREASON (res)) { this = VAR2LIT (var); if (this->val == FALSE) this = NOTLIT (this); other = REASON2LIT (res); assert (other->val == TRUE); assert (this->val == TRUE); res = setimpl (NOTLIT (other), this); } #endif return res; } static void mark_clause_to_be_collected (Cls * cls) { assert (!cls->collect); cls->collect = 1; } static void undo (unsigned new_level) { Lit *lit; Var *v; while (thead > trail) { lit = *--thead; v = LIT2VAR (lit); if (v->level == new_level) { thead++; /* fix pre decrement */ break; } unassign (lit); } level = new_level; ttail = thead; ttail2 = thead; #ifndef NADC ttailado = thead; #endif #ifdef NO_BINARY_CLAUSES if (conflict == &cimpl) resetcimpl (); #endif #ifndef NADC if (conflict && conflict == adoconflict) resetadoconflict (); #endif conflict = mtcls; if (level < adecidelevel) { assert (als < alshead); adecidelevel = 0; alstail = als; } LOG (fprintf (out, "%sback to level %u\n", prefix, level)); } #ifndef NDEBUG static int clause_satisfied (Cls * cls) { Lit **p, **eol, *lit; eol = end_of_lits (cls); for (p = cls->lits; p < eol; p++) { lit = *p; if (lit->val == TRUE) return 1; } return 0; } static void original_clauses_satisfied (void) { Cls **p, *cls; for (p = oclauses; p < ohead; p++) { cls = *p; if (!cls) continue; if (cls->learned) continue; assert (clause_satisfied (cls)); } } static void assumptions_satisfied (void) { Lit *lit, ** p; for (p = als; p < alshead; p++) { lit = *p; assert (lit->val == TRUE); } } #endif static void sflush (void) { double now = picosat_time_stamp (); double delta = now - entered; delta = (delta < 0) ? 0 : delta; seconds += delta; entered = now; } static double mb (void) { return current_bytes / (double) (1 << 20); } static double avglevel (void) { return decisions ? levelsum / decisions : 0.0; } static void rheader (void) { assert (lastrheader <= reports); if (lastrheader == reports) return; lastrheader = reports; fprintf (out, "%s\n", prefix); fprintf (out, "%s %s\n", prefix, rline[0]); fprintf (out, "%s %s\n", prefix, rline[1]); fprintf (out, "%s\n", prefix); } static unsigned dynamic_flips_per_assignment_per_mille (void) { assert (FFLIPPEDPREC >= 1000); return sdflips / (FFLIPPEDPREC / 1000); } #ifdef NLUBY static int high_agility (void) { return dynamic_flips_per_assignment_per_mille () >= 200; } static int very_high_agility (void) { return dynamic_flips_per_assignment_per_mille () >= 250; } #else static int medium_agility (void) { return dynamic_flips_per_assignment_per_mille () >= 230; } #endif static void relemdata (void) { char *p; int x; if (reports < 0) { /* strip trailing white space */ for (x = 0; x <= 1; x++) { p = rline[x] + strlen (rline[x]); while (p-- > rline[x]) { if (*p != ' ') break; *p = 0; } } rheader (); } else fputc ('\n', out); rcount = 0; } static void relemhead (const char * name, int fp, double val) { int x, y, len, size; const char *fmt; unsigned tmp, e; if (reports < 0) { x = rcount & 1; y = (rcount / 2) * 12 + x * 6; if (rcount == 1) sprintf (rline[1], "%6s", ""); len = strlen (name); while (szrline <= len + y + 1) { size = szrline ? 2 * szrline : 128; rline[0] = resize (rline[0], szrline, size); rline[1] = resize (rline[1], szrline, size); szrline = size; } fmt = (len <= 6) ? "%6s%10s" : "%-10s%4s"; sprintf (rline[x] + y, fmt, name, ""); } else if (val < 0) { assert (fp); if (val > -100 && (tmp = val * 10.0 - 0.5) > -1000.0) { fprintf (out, "-%4.1f ", -tmp / 10.0); } else { tmp = -val / 10.0 + 0.5; e = 1; while (tmp >= 100) { tmp /= 10; e++; } fprintf (out, "-%2ue%u ", tmp, e); } } else { if (fp && val < 1000 && (tmp = val * 10.0 + 0.5) < 10000) { fprintf (out, "%5.1f ", tmp / 10.0); } else if (!fp && (tmp = val) < 100000) { fprintf (out, "%5u ", tmp); } else { tmp = val / 10.0 + 0.5; e = 1; while (tmp >= 1000) { tmp /= 10; e++; } fprintf (out, "%3ue%u ", tmp, e); } } rcount++; } inline static void relem (const char *name, int fp, double val) { if (name) relemhead (name, fp, val); else relemdata (); } static unsigned reduce_limit_on_lclauses (void) { unsigned res = lreduce; res += llocked; return res; } static void report (int level, char type) { int rounds; if (verbosity < level) return; sflush (); if (!reports) reports = -1; for (rounds = (reports < 0) ? 2 : 1; rounds; rounds--) { if (reports >= 0) fprintf (out, "%s%c ", prefix, type); relem ("seconds", 1, seconds); relem ("level", 1, avglevel ()); assert (fixed <= max_var); relem ("variables", 0, max_var - fixed); relem ("used", 1, PERCENT (vused, max_var)); relem ("original", 0, noclauses); relem ("conflicts", 0, conflicts); //relem ("decisions", 0, decisions); // relem ("conf/dec", 1, PERCENT(conflicts,decisions)); // relem ("limit", 0, reduce_limit_on_lclauses ()); relem ("learned", 0, nlclauses); // relem ("limit", 1, PERCENT (nlclauses, reduce_limit_on_lclauses ())); relem ("limit", 0, lreduce); #ifdef STATS relem ("learning", 1, PERCENT (llused, lladded)); #endif relem ("agility", 1, dynamic_flips_per_assignment_per_mille () / 10.0); // relem ("original", 0, noclauses); relem ("MB", 1, mb ()); // relem ("lladded", 0, lladded); // relem ("llused", 0, llused); relem (0, 0, 0); reports++; } /* Adapt this to the number of rows in your terminal. */ #define ROWS 25 if (reports % (ROWS - 3) == (ROWS - 4)) rheader (); fflush (out); } static int bcp_queue_is_empty (void) { if (ttail != thead) return 0; if (ttail2 != thead) return 0; #ifndef NADC if (ttailado != thead) return 0; #endif return 1; } static int satisfied (void) { assert (!mtcls); assert (!failed_assumption); if (alstail < alshead) return 0; assert (!conflict); assert (bcp_queue_is_empty ()); return thead == trail + max_var; /* all assigned */ } static void vrescore (void) { Rnk *p, *eor = rnks + max_var; for (p = rnks + 1; p <= eor; p++) if (p->score != INFFLT) p->score = mulflt (p->score, ilvinc); vinc = mulflt (vinc, ilvinc);; #ifdef VISCORES nvinc = mulflt (nvinc, lscore);; #endif } static void inc_score (Var * v) { Flt score; Rnk *r; #ifndef NFL if (simplifying) return; #endif if (!v->level) return; r = VAR2RNK (v); score = r->score; assert (score != INFFLT); score = addflt (score, vinc); assert (score < INFFLT); r->score = score; if (r->pos > 0) hup (r); if (score > lscore) vrescore (); } static void inc_activity (Cls * cls) { Act *p; if (!cls->learned) return; if (cls->size <= 2) return; p = CLS2ACT (cls); *p = addflt (*p, cinc); } static unsigned hashlevel (unsigned l) { return 1u << (l & 31); } static void push (Var * v) { if (dhead == eod) ENLARGE (dfs, dhead, eod); *dhead++ = v; } static Var * pop (void) { assert (dfs < dhead); return *--dhead; } static void analyze (void) { unsigned open, minlevel, siglevels, l, old, i, orig; Lit *this, *other, **p, **q, **eol; Var *v, *u, **m, *start, *uip; Cls *c; assert (conflict); assert (ahead == added); assert (mhead == marked); assert (rhead == resolved); /* 2. Search for First UIP variable and mark all resolved variables. At * the same time determine the minimum decision level involved. Increase * activities of resolved variables. */ q = thead; open = 0; minlevel = level; siglevels = 0; uip = 0; c = conflict; for (;;) { add_antecedent (c); inc_activity (c); eol = end_of_lits (c); for (p = c->lits; p < eol; p++) { other = *p; if (other->val == TRUE) continue; assert (other->val == FALSE); u = LIT2VAR (other); if (u->mark) continue; u->mark = 1; inc_score (u); use_var (u); if (u->level == level) { open++; } else { push_var_as_marked (u); if (u->level) { /* The statistics counter 'nonminimizedllits' sums up the * number of literals that would be added if only the * 'first UIP' scheme for learned clauses would be used * and no clause minimization. */ nonminimizedllits++; if (u->level < minlevel) minlevel = u->level; siglevels |= hashlevel (u->level); } else { assert (!u->level); assert (u->reason); } } } do { if (q == trail) { uip = 0; goto DONE_FIRST_UIP; } this = *--q; uip = LIT2VAR (this); } while (!uip->mark); uip->mark = 0; c = var2reason (uip); #ifdef NO_BINARY_CLAUSES if (c == &impl) resetimpl (); #endif open--; if ((!open && level) || !c) break; assert (c); } DONE_FIRST_UIP: if (uip) { assert (level); this = VAR2LIT (uip); this += (this->val == TRUE); nonminimizedllits++; minimizedllits++; add_lit (this); #ifdef STATS if (uip->reason) uips++; #endif } else assert (!level); /* 3. Try to mark more intermediate variables, with the goal to minimize * the conflict clause. This is a DFS from already marked variables * backward through the implication graph. It tries to reach other marked * variables. If the search reaches an unmarked decision variable or a * variable assigned below the minimum level of variables in the first uip * learned clause or a level on which no variable has been marked, then * the variable from which the DFS is started is not redundant. Otherwise * the start variable is redundant and will eventually be removed from the * learned clause in step 4. We initially implemented BFS, but then * profiling revelead that this step is a bottle neck for certain * incremental applications. After switching to DFS this hot spot went * away. */ orig = mhead - marked; for (i = 0; i < orig; i++) { start = marked[i]; assert (start->mark); assert (start != uip); assert (start->level < level); if (!start->reason) continue; old = mhead - marked; assert (dhead == dfs); push (start); while (dhead > dfs) { u = pop (); assert (u->mark); c = var2reason (u); #ifdef NO_BINARY_CLAUSES if (c == &impl) resetimpl (); #endif if (!c || ((l = u->level) && (l < minlevel || ((hashlevel (l) & ~siglevels))))) { while (mhead > marked + old) /* reset all marked */ (*--mhead)->mark = 0; dhead = dfs; /* and DFS stack */ break; } eol = end_of_lits (c); for (p = c->lits; p < eol; p++) { v = LIT2VAR (*p); if (v->mark) continue; mark_var (v); push (v); } } } for (m = marked; m < mhead; m++) { v = *m; assert (v->mark); assert (!v->resolved); use_var (v); c = var2reason (v); if (!c) continue; #ifdef NO_BINARY_CLAUSES if (c == &impl) resetimpl (); #endif eol = end_of_lits (c); for (p = c->lits; p < eol; p++) { other = *p; u = LIT2VAR (other); if (!u->level) continue; if (!u->mark) /* 'MARKTEST' */ break; } if (p != eol) continue; add_antecedent (c); v->resolved = 1; } for (m = marked; m < mhead; m++) { v = *m; assert (v->mark); v->mark = 0; if (v->resolved) { v->resolved = 0; continue; } this = VAR2LIT (v); if (this->val == TRUE) this++; /* actually NOTLIT */ add_lit (this); minimizedllits++; } assert (ahead <= eoa); assert (rhead <= eor); mhead = marked; } static void fanalyze (void) { Lit ** eol, ** p, * lit; Cls * cls, * reason; Var * v, * u; int next; double start = picosat_time_stamp (); assert (failed_assumption); assert (failed_assumption->val == FALSE); v = LIT2VAR (failed_assumption); reason = var2reason (v); if (!reason) return; #ifdef NO_BINARY_CLAUSES if (reason == &impl) resetimpl (); #endif eol = end_of_lits (reason); for (p = reason->lits; p != eol; p++) { lit = *p; u = LIT2VAR (lit); if (u == v) continue; if (u->reason) break; } if (p == eol) return; assert (ahead == added); assert (mhead == marked); assert (rhead == resolved); next = 0; mark_var (v); add_lit (NOTLIT (failed_assumption)); do { v = marked[next++]; use_var (v); if (v->reason) { reason = var2reason (v); #ifdef NO_BINARY_CLAUSES if (reason == &impl) resetimpl (); #endif add_antecedent (reason); eol = end_of_lits (reason); for (p = reason->lits; p != eol; p++) { lit = *p; u = LIT2VAR (lit); if (u == v) continue; if (u->mark) continue; mark_var (u); } } else { lit = VAR2LIT (v); if (lit->val == TRUE) lit = NOTLIT (lit); add_lit (lit); } } while (marked + next < mhead); cls = add_simplified_clause (1); v = LIT2VAR (failed_assumption); reason = var2reason (v); #ifdef NO_BINARY_CLAUSES if (reason == &impl) resetimpl (); else #endif { assert (reason->locked); reason->locked = 0; } if (reason->learned && reason->size > 2) { assert (llocked > 0); llocked--; } v->reason = cls; assert (cls->learned); assert (!cls->locked); cls->locked = 1; if (cls->size > 2) { llocked++; assert (llocked > 0); } while (mhead > marked) (*--mhead)->mark = 0; if (verbosity) fprintf (out, "%sfanalyze took %.1f seconds\n", prefix, picosat_time_stamp () - start); } /* Propagate assignment of 'this' to 'FALSE' by visiting all binary clauses in * which 'this' occurs. */ inline static void prop2 (Lit * this) { #ifdef NO_BINARY_CLAUSES Lit ** l, ** start; Ltk * lstk; #else Cls * cls, ** p; Cls * next; #endif Lit * other; Val tmp; assert (this->val == FALSE); #ifdef NO_BINARY_CLAUSES lstk = LIT2IMPLS (this); start = lstk->start; l = start + lstk->count; while (l != start) { #ifdef STATS /* The counter 'visits' is the number of clauses that are * visited during propagations of assignments. */ visits++; bvisits++; #endif other = *--l; tmp = other->val; if (tmp == TRUE) { #ifdef STATS othertrue++; othertrue2++; if (LIT2VAR (other)->level < level) othertrue2u++; #endif continue; } if (tmp != FALSE) { assign_forced (other, LIT2REASON (NOTLIT(this))); continue; } if (conflict == &cimpl) resetcimpl (); conflict = setcimpl (this, other); } #else /* Traverse all binary clauses with 'this'. Head/Tail pointers for binary * clauses do not have to be modified here. */ p = LIT2IMPLS (this); for (cls = *p; cls; cls = next) { #ifdef STATS visits++; bvisits++; #endif assert (!cls->collect); #ifdef TRACE assert (!cls->collected); #endif assert (cls->size == 2); other = cls->lits[0]; if (other == this) { next = cls->next[0]; other = cls->lits[1]; #ifdef STATS #endif } else next = cls->next[1]; tmp = other->val; if (tmp == TRUE) { #ifdef STATS othertrue++; othertrue2++; if (LIT2VAR (other)->level < level) othertrue2u++; #endif continue; } if (tmp == FALSE) conflict = cls; else assign_forced (other, cls); /* unit clause */ } #endif /* !defined(NO_BINARY_CLAUSES) */ } #ifndef NDSC static int should_disconnect_head_tail (Lit * lit) { unsigned lit_level; Var * v; assert (lit->val == TRUE); v = LIT2VAR (lit); lit_level = v->level; if (!lit_level) return 1; #ifndef NFL if (simplifying) return 0; #endif return lit_level < level; } #endif inline static void propl (Lit * this) { Lit **l, *other, *prev, *new_lit, **eol; Cls *next, **htp_ptr, **new_htp_ptr; Cls *cls; #ifdef STATS unsigned size; #endif htp_ptr = LIT2HTPS (this); assert (this->val == FALSE); /* Traverse all non binary clauses with 'this'. Head/Tail pointers are * updated as well. */ for (cls = *htp_ptr; cls; cls = next) { #ifdef STATS visits++; size = cls->size; if (size == 2) bvisits++; else if (size >= 3) { traversals++; /* other is dereferenced at least */ if (size == 3) tvisits++; else if (size >= 4) { lvisits++; ltraversals++; } } #endif #ifdef TRACE assert (!cls->collected); #endif assert (cls->size > 0); /* With assumptions we need to traverse unit clauses as well. */ if (cls->size == 1) { assert (!conflict); conflict = cls; break; } other = cls->lits[0]; if (other != this) { cls->lits[0] = this; cls->lits[1] = other; next = cls->next[1]; cls->next[1] = cls->next[0]; cls->next[0] = next; } else { other = cls->lits[1]; next = cls->next[0]; } assert (other == cls->lits[1]); assert (this == cls->lits[0]); assert (next == cls->next[0]); assert (!cls->collect); if (other->val == TRUE) { #ifdef STATS othertrue++; othertruel++; #endif #ifndef NDSC if (should_disconnect_head_tail (other)) { new_htp_ptr = LIT2DHTPS (other); cls->next[0] = *new_htp_ptr; *new_htp_ptr = cls; #ifdef STATS othertruelu++; #endif *htp_ptr = next; continue; } #endif htp_ptr = cls->next; continue; } l = cls->lits + 1; eol = cls->lits + cls->size; prev = this; while (++l != eol) { #ifdef STATS if (size >= 3) { traversals++; if (size > 3) ltraversals++; } #endif new_lit = *l; *l = prev; prev = new_lit; if (new_lit->val != FALSE) break; } if (l == eol) { while (l > cls->lits + 2) { new_lit = *--l; *l = prev; prev = new_lit; } assert (cls->lits[0] == this); assert (other == cls->lits[1]); if (other->val == FALSE) /* found conflict */ { assert (!conflict); conflict = cls; return; } assign_forced (other, cls); /* unit clause */ htp_ptr = cls->next; } else { assert (new_lit->val == TRUE || new_lit->val == UNDEF); cls->lits[0] = new_lit; // *l = this; new_htp_ptr = LIT2HTPS (new_lit); cls->next[0] = *new_htp_ptr; *new_htp_ptr = cls; *htp_ptr = next; } } } #ifndef NADC static unsigned primes[] = { 996293, 330643, 753947, 500873 }; #define PRIMES ((sizeof primes)/sizeof *primes) static unsigned hash_ado (Lit ** ado, unsigned salt) { unsigned i, res, tmp; Lit ** p, * lit; assert (salt < PRIMES); i = salt; res = 0; for (p = ado; (lit = *p); p++) { assert (lit->val); tmp = res >> 31; res <<= 1; if (lit->val > 0) res |= 1; assert (i < PRIMES); res *= primes[i++]; if (i == PRIMES) i = 0; res += tmp; } return res & (szadotab - 1); } static unsigned cmp_ado (Lit ** a, Lit ** b) { Lit ** p, ** q, * l, * k; int res; for (p = a, q = b; (l = *p); p++, q++) { k = *q; assert (k); if ((res = (l->val - k->val))) return res; } assert (!*q); return 0; } static Lit *** find_ado (Lit ** ado) { Lit *** res, ** other; unsigned pos, delta; pos = hash_ado (ado, 0); assert (pos < szadotab); res = adotab + pos; other = *res; if (!other || !cmp_ado (other, ado)) return res; delta = hash_ado (ado, 1); if (!(delta & 1)) delta++; assert (delta & 1); assert (delta < szadotab); for (;;) { pos += delta; if (pos >= szadotab) pos -= szadotab; assert (pos < szadotab); res = adotab + pos; other = *res; if (!other || !cmp_ado (other, ado)) return res; } } static void enlarge_adotab (void) { /* TODO make this generic */ ABORTIF (szadotab, "internal: all different objects table needs larger initial size"); assert (!nadotab); szadotab = 10000; NEWN (adotab, szadotab); CLRN (adotab, szadotab); } static int propado (Var * v) { Lit ** p, ** q, *** adotabpos, **ado, * lit; Var * u; if (level && adodisabled) return 1; assert (!conflict); assert (!adoconflict); assert (VAR2LIT (v)->val != UNDEF); assert (!v->adotabpos); if (!v->ado) return 1; assert (v->inado); for (p = v->ado; (lit = *p); p++) if (lit->val == UNDEF) { u = LIT2VAR (lit); assert (!u->ado); u->ado = v->ado; v->ado = 0; return 1; } if (4 * nadotab >= 3 * szadotab) /* at least 75% filled */ enlarge_adotab (); adotabpos = find_ado (v->ado); ado = *adotabpos; if (!ado) { nadotab++; v->adotabpos = adotabpos; *adotabpos = v->ado; return 1; } assert (ado != v->ado); adoconflict = new_clause (2 * llength (ado), 1); q = adoconflict->lits; for (p = ado; (lit = *p); p++) *q++ = lit->val == FALSE ? lit : NOTLIT (lit); for (p = v->ado; (lit = *p); p++) *q++ = lit->val == FALSE ? lit : NOTLIT (lit); assert (q == ENDOFCLS (adoconflict)); conflict = adoconflict; adoconflicts++; return 0; } #endif static void bcp (void) { int props = 0; assert (!conflict); if (mtcls || conflict) return; for (;;) { if (ttail2 < thead) /* prioritize implications */ { props++; prop2 (NOTLIT (*ttail2++)); } else if (ttail < thead) /* unit clauses or clauses with length > 2 */ { if (conflict) break; propl (NOTLIT (*ttail++)); if (conflict) break; } #ifndef NADC else if (ttailado < thead) { if (conflict) break; propado (LIT2VAR (*ttailado++)); if (conflict) break; } #endif else break; /* all assignments propagated, so break */ } propagations += props; } /* This version of 'drive' is independent of the global variable 'level' and * thus even works if we resolve ala 'relsat' without driving an assignment. */ static unsigned drive (void) { Var *v, *first, *second; Lit **p; first = 0; for (p = added; p < ahead; p++) { v = LIT2VAR (*p); if (!first || v->level > first->level) first = v; } if (!first) return 0; second = 0; for (p = added; p < ahead; p++) { v = LIT2VAR (*p); if (v->level == first->level) continue; if (!second || v->level > second->level) second = v; } if (!second) return 0; return second->level; } #ifdef VISCORES static void viscores (void) { Rnk *p, *eor = rnks + max_var; char name[100], cmd[200]; FILE * data; Flt s; int i; for (p = rnks + 1; p <= eor; p++) { s = p->score; if (s == INFFLT) continue; s = mulflt (s, nvinc); assert (flt2double (s) <= 1.0); } sprintf (name, "/tmp/picosat-viscores/data/%08u", conflicts); sprintf (cmd, "sort -n|nl>%s", name); data = popen (cmd, "w"); for (p = rnks + 1; p <= eor; p++) { s = p->score; if (s == INFFLT) continue; s = mulflt (s, nvinc); fprintf (data, "%lf %d\n", 100.0 * flt2double (s), (int)(p - rnks)); } fflush (data); pclose (data); for (i = 0; i < 8; i++) { sprintf (cmd, "awk '$3%%8==%d' %s>%s.%d", i, name, name, i); system (cmd); } fprintf (fviscores, "set title \"%u\"\n", conflicts); fprintf (fviscores, "plot [0:%u] 0, 100 * (1 - 1/1.1), 100", max_var); for (i = 0; i < 8; i++) fprintf (fviscores, ", \"%s.%d\" using 1:2:3 with labels tc lt %d", name, i, i + 1); fputc ('\n', fviscores); fflush (fviscores); #ifndef WRITEGIF usleep (50000); /* refresh rate of 20 Hz */ #endif } #endif static void crescore (void) { Cls **p, *cls; Act *a; Flt factor; int l = log2flt (cinc); assert (l > 0); factor = base2flt (1, -l); for (p = lclauses; p != lhead; p++) { cls = *p; if (!cls) continue; #ifdef TRACE if (cls->collected) continue; #endif assert (cls->learned); if (cls->size <= 2) continue; a = CLS2ACT (cls); *a = mulflt (*a, factor); } cinc = mulflt (cinc, factor); } static void inc_vinc (void) { #ifdef VISCORES nvinc = mulflt (nvinc, fvinc); #endif vinc = mulflt (vinc, ifvinc); } inline static void inc_max_var (void) { Lit *lit; Rnk *r; Var *v; assert (max_var < size_vars); max_var++; /* new index of variable */ assert (max_var); /* no unsigned overflow */ if (max_var == size_vars) enlarge (size_vars + (size_vars + 3) / 4); /* increase by 25% */ assert (max_var < size_vars); lit = lits + 2 * max_var; lit[0].val = lit[1].val = UNDEF; memset (htps + 2 * max_var, 0, 2 * sizeof *htps); #ifndef NDSC memset (dhtps + 2 * max_var, 0, 2 * sizeof *dhtps); #endif memset (impls + 2 * max_var, 0, 2 * sizeof *impls); memset (jwh + 2 * max_var, 0, 2 * sizeof *jwh); v = vars + max_var; /* initialize variable components */ CLR (v); r = rnks + max_var; /* initialize rank */ CLR (r); hpush (r); } static void force (Cls * cls) { Lit ** p, ** eol, * lit, * forced; Cls * reason; Var *v; forced = 0; reason = cls; eol = end_of_lits (cls); for (p = cls->lits; p < eol; p++) { lit = *p; if (lit->val == UNDEF) { assert (!forced); forced = lit; #ifdef NO_BINARY_CLAUSES if (cls == &impl) reason = LIT2REASON (NOTLIT (p[p == cls->lits ? 1 : -1])); #endif } else assert (lit->val == FALSE); } #ifdef NO_BINARY_CLAUSES if (cls == &impl) resetimpl (); #endif if (!forced) return; assign_forced (forced, reason); v = LIT2VAR (forced); } static void inc_lreduce (void) { #ifdef STATS inclreduces++; #endif lreduce *= FREDUCE; lreduce /= 100; report (1, '+'); } static void backtrack (void) { unsigned new_level; Cls * cls; conflicts++; LOG (fprintf (out, "%sconflict ", prefix); dumpclsnl (conflict)); analyze (); new_level = drive (); // TODO: why not? assert (new_level != 1 || (ahead - added) == 2); cls = add_simplified_clause (1); undo (new_level); force (cls); if ( #ifndef NFL !simplifying && #endif !--lreduceadjustcnt) { lreduceadjustinc *= 15; lreduceadjustinc /= 10; lreduceadjustcnt = lreduceadjustinc; inc_lreduce (); } if (verbosity >= 4 && !(conflicts % 1000)) report (4, 'C'); } static void inc_cinc (void) { cinc = mulflt (cinc, fcinc); if (lcinc < cinc) crescore (); } static void incincs (void) { inc_vinc (); inc_cinc (); #ifdef VISCORES viscores (); #endif } static void disconnect_clause (Cls * cls) { assert (cls->connected); if (cls->size > 2) { if (cls->learned) { assert (nlclauses > 0); nlclauses--; assert (llits >= cls->size); llits -= cls->size; } else { assert (noclauses > 0); noclauses--; assert (olits >= cls->size); olits -= cls->size; } } #ifndef NDEBUG cls->connected = 0; #endif } static int clause_is_toplevel_satisfied (Cls * cls) { Lit *lit, **p, **eol = end_of_lits (cls); Var *v; for (p = cls->lits; p < eol; p++) { lit = *p; if (lit->val == TRUE) { v = LIT2VAR (lit); if (!v->level) return 1; } } return 0; } static int collect_clause (Cls * cls) { assert (cls->collect); cls->collect = 0; #ifdef TRACE assert (!cls->collected); cls->collected = 1; #endif disconnect_clause (cls); #ifdef TRACE if (trace && (!cls->learned || cls->used)) return 0; #endif delete_clause (cls); return 1; } static size_t collect_clauses (void) { Cls *cls, **p, **q, * next; Lit * lit, * eol; size_t res; Var * v; int i; res = current_bytes; eol = lits + 2 * max_var + 1; for (lit = lits + 2; lit <= eol; lit++) { for (i = 0; i <= 1; i++) { if (i) { #ifdef NO_BINARY_CLAUSES Ltk * lstk = LIT2IMPLS (lit); Lit ** r, ** s; r = lstk->start; for (s = r; s < lstk->start + lstk->count; s++) { Lit * other = *s; Var *v = LIT2VAR (other); if (v->level || other->val != TRUE) *r++ = other; } lstk->count = r - lstk->start; continue; #else p = LIT2IMPLS (lit); #endif } else p = LIT2HTPS (lit); for (cls = *p; cls; cls = next) { q = cls->next; if (cls->lits[0] != lit) q++; next = *q; if (cls->collect) *p = next; else p = q; } } } #ifndef NDSC for (lit = lits + 2; lit <= eol; lit++) { p = LIT2DHTPS (lit); while ((cls = *p)) { Lit * other = cls->lits[0]; if (other == lit) { q = cls->next + 1; } else { assert (cls->lits[1] == lit); q = cls->next; } if (cls->collect) *p = *q; else p = q; } } #endif for (v = vars + 1; v <= vars + max_var; v++) { cls = v->reason; if (!cls) continue; #ifdef NO_BINARY_CLAUSES if (ISLITREASON (cls)) continue; #endif if (cls->collect) v->reason = 0; } for (p = SOC; p != EOC; p = NXC (p)) { cls = *p; if (!cls) continue; if (!cls->collect) continue; if (collect_clause (cls)) *p = 0; } #ifdef TRACE if (!trace) #endif { q = oclauses; for (p = q; p < ohead; p++) if ((cls = *p)) *q++ = cls; ohead = q; q = lclauses; for (p = q; p < lhead; p++) if ((cls = *p)) *q++ = cls; lhead = q; } assert (current_bytes <= res); res -= current_bytes; recycled += res; LOG (fprintf (out, "%scollected %ld bytes\n", prefix, res)); return res; } static int need_to_reduce (void) { return nlclauses >= reduce_limit_on_lclauses (); } #ifdef NLUBY static void inc_drestart (void) { drestart *= FRESTART; drestart /= 100; if (drestart >= MAXRESTART) drestart = MAXRESTART; } static void inc_ddrestart (void) { ddrestart *= FRESTART; ddrestart /= 100; if (ddrestart >= MAXRESTART) ddrestart = MAXRESTART; } #else static int luby (int i) { int k; for (k = 1; k < 32; k++) if (i == (1 << k) - 1) return 1 << (k - 1); for (k = 1;; k++) if ((1 << (k - 1)) <= i && i < (1 << k) - 1) return luby (i - (1 << (k-1)) + 1); } #endif #ifndef NLUBY static void inc_lrestart (int skip) { unsigned delta; delta = 100 * luby (++lubycnt); lrestart = conflicts + delta; if (waslubymaxdelta) report (1, skip ? 'N' : 'R'); else report (2, skip ? 'n' : 'r'); if (delta > lubymaxdelta) { lubymaxdelta = delta; waslubymaxdelta = 1; } else waslubymaxdelta = 0; } #endif static void init_restart (void) { #ifdef NLUBY /* TODO: why is it better in incremental usage to have smaller initial * outer restart interval? */ ddrestart = calls > 1 ? MINRESTART : 1000; drestart = MINRESTART; lrestart = conflicts + drestart; #else lubycnt = 0; lubymaxdelta = 0; waslubymaxdelta = 0; inc_lrestart (0); #endif } static void restart (void) { int skip; #ifdef NLUBY char kind; int outer; inc_drestart (); outer = (drestart >= ddrestart); if (outer) skip = very_high_agility (); else skip = high_agility (); #else skip = medium_agility (); #endif #ifdef STATS if (skip) skippedrestarts++; #endif assert (conflicts >= lrestart); if (!skip) { restarts++; assert (level > 1); LOG (fprintf (out, "%srestart %u\n", prefix, restarts)); undo (0); } #ifdef NLUBY if (outer) { kind = skip ? 'N' : 'R'; inc_ddrestart (); drestart = MINRESTART; } else if (skip) { kind = 'n'; } else { kind = 'r'; } assert (drestart <= MAXRESTART); lrestart = conflicts + drestart; assert (lrestart > conflicts); report (outer ? 1 : 2, kind); #else inc_lrestart (skip); #endif } inline static void assign_decision (Lit * lit) { assert (!conflict); level++; LOG (fprintf (out, "%snew level %u\n", prefix, level)); LOG (fprintf (out, "%sassign %d at level %d <= DECISION\n", prefix, lit2int (lit), level)); assign (lit, 0); } #ifndef NFL static int lit_has_binary_clauses (Lit * lit) { #ifdef NO_BINARY_CLAUSES Ltk* lstk = LIT2IMPLS (lit); return lstk->count != 0; #else return *LIT2IMPLS (lit) != 0; #endif } static void flbcp (void) { #ifdef STATS unsigned long long propagaions_before_bcp = propagations; #endif bcp (); #ifdef STATS flprops += propagations - propagaions_before_bcp; #endif } inline static int cmp_inverse_rnk (Rnk * a, Rnk * b) { return -cmp_rnk (a, b); } inline static Flt rnk2jwh (Rnk * r) { Flt res, sum, pjwh, njwh; Lit * plit, * nlit; plit = RNK2LIT (r); nlit = plit + 1; pjwh = *LIT2JWH (plit); njwh = *LIT2JWH (nlit); res = mulflt (pjwh, njwh); sum = addflt (pjwh, njwh); sum = mulflt (sum, base2flt (1, -10)); res = addflt (res, sum); return res; } static int cmp_inverse_jwh_rnk (Rnk * r, Rnk * s) { Flt a = rnk2jwh (r); Flt b = rnk2jwh (s); int res = cmpflt (a, b); if (res) return -res; return cmp_inverse_rnk (r, s); } static void faillits (void) { unsigned i, j, old_trail_count, common, saved_count; unsigned new_saved_size, oldladded = ladded; unsigned long long limit, delta; Lit * lit, * other, * pivot; int new_trail_count; Rnk * r, ** p, ** q; Var * v; if (heap + 1 >= hhead) return; if (propagations < fllimit) return; flcalls++; #ifdef STATSA flrounds++; #endif delta = propagations/10; if (delta >= 100*1000*1000) delta = 100*1000*1000; else if (delta <= 100*1000) delta = 100*1000; limit = propagations + delta; fllimit = propagations; assert (!level); assert (simplifying); if (flcalls <= 1) sort (Rnk *, cmp_inverse_jwh_rnk, heap + 1, hhead - (heap + 1)); else sort (Rnk *, cmp_inverse_rnk, heap + 1, hhead - (heap + 1)); i = 1; /* NOTE: heap starts at position '1' */ while (propagations < limit) { if (heap + i == hhead) { if (ladded == oldladded) break; i = 1; #ifdef STATS flrounds++; #endif oldladded = ladded; } assert (heap + i < hhead); r = heap[i++]; lit = RNK2LIT (r); if (lit->val) continue; if (!lit_has_binary_clauses (NOTLIT (lit))) { #ifdef STATS flskipped++; #endif continue; } #ifdef STATS fltried++; #endif LOG (fprintf (out, "%strying %d as failed literal\n", prefix, lit2int (lit))); assign_decision (lit); old_trail_count = thead - trail; flbcp (); if (conflict) { EXPLICITLY_FAILED_LITERAL: LOG (fprintf (out, "%sfound explicitly failed literal %d\n", prefix, lit2int (lit))); failedlits++; efailedlits++; backtrack (); flbcp (); if (!conflict) continue; CONTRADICTION: assert (!level); backtrack (); assert (mtcls); goto RETURN; } if (propagations >= limit) { undo (0); break; } lit = NOTLIT (lit); if (!lit_has_binary_clauses (NOTLIT (lit))) { #ifdef STATS flskipped++; #endif undo (0); continue; } #ifdef STATS fltried++; #endif LOG (fprintf (out, "%strying %d as failed literals\n", prefix, lit2int (lit))); new_trail_count = thead - trail; saved_count = new_trail_count - old_trail_count; if (saved_count > saved_size) { new_saved_size = saved_size ? 2 * saved_size : 1; while (saved_count > new_saved_size) new_saved_size *= 2; RESIZEN (saved, saved_size, new_saved_size); saved_size = new_saved_size; } for (j = 0; j < saved_count; j++) { other = trail[old_trail_count + j]; saved[j] = trail[old_trail_count + j]; } undo (0); assign_decision (lit); flbcp (); if (conflict) goto EXPLICITLY_FAILED_LITERAL; pivot = (thead - trail <= new_trail_count) ? lit : NOTLIT (lit); common = 0; for (j = 0; j < saved_count; j++) if ((other = saved[j])->val == TRUE) saved[common++] = other; undo (0); LOG (if (common) fprintf (out, "%sfound %d literals implied by %d and %d\n", prefix, common, lit2int (NOTLIT (lit)), lit2int (lit))); for (j = 0; j < common /* TODO: For some Velev benchmarks, extracting the common implicit * failed literals took quite some time. This needs to be fixed by * a dedicated analyzer. Up to then we bound the number of * propagations in this loop as well. */ && propagations < limit + delta ; j++) { other = saved[j]; if (other->val == TRUE) continue; assert (!other->val); LOG (fprintf (out, "%sforcing %d as forced implicitly failed literal\n", prefix, lit2int (other))); assert (pivot != NOTLIT (other)); assert (pivot != other); assign_decision (NOTLIT (other)); flbcp (); assert (level == 1); if (conflict) { backtrack (); assert (!level); } else { assign_decision (pivot); flbcp (); backtrack (); if (level) { assert (level == 1); flbcp (); if (conflict) { backtrack (); assert (!level); } else { assign_decision (NOTLIT (pivot)); flbcp (); backtrack (); if (level) { assert (level == 1); flbcp (); if (!conflict) { #ifdef STATS floopsed++; #endif undo (0); continue; } backtrack (); } assert (!level); } assert (!level); } } assert (!level); flbcp (); failedlits++; ifailedlits++; if (conflict) goto CONTRADICTION; } } fllimit += 9 * (propagations - fllimit); /* 10% for failed literals */ RETURN: /* First flush top level assigned literals. Those are prohibited from * being pushed up the heap during 'faillits' since 'simplifying' is set. */ assert (heap < hhead); for (p = q = heap + 1; p < hhead; p++) { r = *p; v = vars + (r - rnks); lit = RNK2LIT (r); if (lit->val) r->pos = 0; else *q++ = r; } /* Then resort with respect to EVSIDS score and fix positions. */ sort (Rnk *, cmp_inverse_rnk, heap + 1, hhead - (heap + 1)); for (p = heap + 1; p < hhead; p++) (*p)->pos = p - heap; } #endif static void simplify (void) { unsigned collect, delta; size_t bytes_collected; Cls **p, *cls; assert (!mtcls); assert (!satisfied ()); assert (lsimplify <= propagations); assert (fsimplify <= fixed); #ifndef NFL if (level) undo (0); simplifying = 1; faillits (); simplifying = 0; if (mtcls) return; #endif collect = 0; for (p = SOC; p != EOC; p = NXC (p)) { cls = *p; if (!cls) continue; #ifdef TRACE if (cls->collected) continue; #endif if (cls->locked) continue; assert (!cls->collect); if (clause_is_toplevel_satisfied (cls)) { mark_clause_to_be_collected (cls); collect++; } } if (collect) { bytes_collected = collect_clauses (); #ifdef STATS srecycled += bytes_collected; #endif } delta = 10 * (olits + llits) + 100000; if (delta > 2000000) delta = 2000000; lsimplify = propagations + delta; fsimplify = fixed; simps++; report (1, 's'); } static void iteration (void) { assert (!level); assert (bcp_queue_is_empty ()); assert (isimplify < fixed); iterations++; report (2, 'i'); #ifdef NLUBY drestart = MINRESTART; lrestart = conflicts + drestart; #else init_restart (); #endif isimplify = fixed; } static int cmp_activity (Cls * c, Cls * d) { Act a; Act b; assert (c->learned); assert (d->learned); a = *CLS2ACT (c); b = *CLS2ACT (d); if (a < b) return -1; if (b < a) return 1; /* Prefer shorter clauses. */ if (c->size < d->size) return 1; if (c->size > d->size) return -1; return 0; } static void reduce (unsigned percentage) { unsigned rcount, lcollect, collect, target, ld; size_t bytes_collected; Cls **p, *cls; Act minact; lastreduceconflicts = conflicts; assert (percentage <= 100); LOG (fprintf (out, "%sreducing %u%% learned clauses\n", prefix, percentage)); while (nlclauses - llocked > (unsigned)(eor - resolved)) ENLARGE (resolved, rhead, eor); collect = 0; lcollect = 0; for (p = ((fsimplify < fixed) ? SOC : lclauses); p != EOC; p = NXC (p)) { cls = *p; if (!cls) continue; #ifdef TRACE if (cls->collected) continue; #endif if (cls->locked) continue; assert (!cls->collect); if (fsimplify < fixed && clause_is_toplevel_satisfied (cls)) { mark_clause_to_be_collected (cls); collect++; if (cls->learned && cls->size > 2) lcollect++; continue; } if (cls->fixed) continue; if (!cls->learned) continue; if (cls->size <= 2) continue; assert (rhead < eor); *rhead++ = cls; } assert (rhead <= eor); fsimplify = fixed; rcount = rhead - resolved; sort (Cls *, cmp_activity, resolved, rcount); assert (nlclauses >= lcollect); target = nlclauses - lcollect + 1; for (ld = 1; ld < 32 && ((unsigned) (1 << ld)) < target; ld++) ; minact = mulflt (cinc, base2flt (1, -ld)); target = (percentage * target + 99) / 100; if (target >= rcount) { target = rcount; } else if (*CLS2ACT (resolved[target]) < minact) { /* If the distribution of clause activities is skewed and the median * is actually below the maximum average activity, then we collect all * clauses below this activity. */ while (++target < rcount && *CLS2ACT (resolved[target]) < minact) ; } else { while (target > 0 && !cmp_activity (resolved[target - 1], resolved[target])) target--; } rhead = resolved + target; while (rhead > resolved) { cls = *--rhead; mark_clause_to_be_collected (cls); collect++; if (cls->learned && cls->size > 2) /* just for consistency */ lcollect++; } if (collect) { reductions++; bytes_collected = collect_clauses (); #ifdef STATS rrecycled += bytes_collected; #endif report (2, '-'); } if (!lcollect) inc_lreduce (); /* avoid dead lock */ assert (rhead == resolved); } static void init_reduce (void) { lreduce = loadded / 2; if (lreduce < 100) lreduce = 100; #if 0 if (lreduce > 10000) lreduce = 10000; #endif if (verbosity) fprintf (out, "%s\n%sinitial reduction limit %u clauses\n%s\n", prefix, prefix, lreduce, prefix); } static unsigned rng (void) { unsigned res = srng; srng *= 1664525u; srng += 1013904223u; NOLOG (fprintf (out, "%srng () = %u\n", prefix, res)); return res; } static unsigned rrng (unsigned low, unsigned high) { unsigned long long tmp; unsigned res, elements; assert (low <= high); elements = high - low + 1; tmp = rng (); tmp *= elements; tmp >>= 32; tmp += low; res = tmp; NOLOG (fprintf (out, "%srrng (%u, %u) = %u\n", prefix, low, high, res)); assert (low <= res); assert (res <= high); return res; } static Lit * decide_phase (Lit * lit) { Lit * not_lit = NOTLIT (lit); Var *v = LIT2VAR (lit); assert (LIT2SGN (lit) > 0); if (!v->assigned) { #ifdef STATS staticphasedecisions++; #endif if (defaultphase == 1) { /* assign to TRUE */ } else if (defaultphase == 0) { /* assign to FALSE */ lit = not_lit; } else if (defaultphase == 3) { /* randomly assign default phase */ if (rrng (1, 2) != 2) lit = not_lit; } else if (*LIT2JWH(lit) <= *LIT2JWH (not_lit)) { /* assign to FALSE (Jeroslow-Wang says there are more short * clauses with negative occurence of this variable, so satisfy * those, to minimize BCP) */ lit = not_lit; } else { /* assign to TRUE (... but strictly more positive occurrences) */ } } else { /* repeat last phase: phase saving heuristic */ if (v->phase) { /* assign to TRUE (last phase was TRUE as well) */ } else { /* assign to FALSE (last phase was FALSE as well) */ lit = not_lit; } } return lit; } static unsigned gcd (unsigned a, unsigned b) { unsigned tmp; assert (a); assert (b); if (a < b) { tmp = a; a = b; b = tmp; } while (b) { assert (a >= b); tmp = b; b = a % b; a = tmp; } return a; } static Lit * rdecide (void) { unsigned idx, delta, spread; Lit * res; spread = RDECIDE; if (rrng (1, spread) != 2) return 0; assert (1 <= max_var); idx = rrng (1, max_var); res = int2lit (idx); if (res->val != UNDEF) { delta = rrng (1, max_var); while (gcd (delta, max_var) != 1) delta--; assert (1 <= delta); assert (delta <= max_var); do { idx += delta; if (idx > max_var) idx -= max_var; res = int2lit (idx); } while (res->val != UNDEF); } #ifdef STATS rdecisions++; #endif res = decide_phase (res); LOG (fprintf (out, "%srdecide %d\n", prefix, lit2int (res))); return res; } static Lit * sdecide (void) { Rnk *r, * tmp; Lit *res; for (;;) { r = htop (); res = RNK2LIT (r); if (res->val == UNDEF) break; tmp = hpop (); assert (tmp == r); NOLOG (fprintf (out, "%shpop %u %u %u\n", prefix, r - rnks, FLTMANTISSA(r->score), FLTEXPONENT(r->score))); } #ifdef STATS sdecisions++; #endif res = decide_phase (res); LOG (fprintf (out, "%ssdecide %d\n", prefix, lit2int (res))); return res; } static Lit * adecide (void) { Lit *lit; Var * v; assert (als < alshead); assert (!failed_assumption); while (alstail < alshead) { lit = *alstail++; if (lit->val == FALSE) { failed_assumption = lit; v = LIT2VAR (lit); use_var (v); LOG (fprintf (out, "%sfirst failed assumption %d\n", prefix, lit2int (failed_assumption))); fanalyze (); return 0; } if (lit->val == TRUE) { v = LIT2VAR (lit); if (v->level > adecidelevel) adecidelevel = v->level; continue; } #ifdef STATS assumptions++; #endif LOG (fprintf (out, "%sadecide %d\n", prefix, lit2int (lit))); adecidelevel = level + 1; return lit; } return 0; } static void decide (void) { Lit * lit; assert (!satisfied ()); assert (!conflict); if (alstail < alshead && (lit = adecide ())) ; else if (failed_assumption) return; else if (satisfied ()) return; else if (!(lit = rdecide ())) lit = sdecide (); assert (lit); assign_decision (lit); levelsum += level; decisions++; } static int sat (int l) { int count = 0, backtracked; if (!conflict) bcp (); if (conflict) backtrack (); if (mtcls) return PICOSAT_UNSATISFIABLE; if (satisfied ()) goto SATISFIED; if (lsimplify <= propagations) simplify (); if (mtcls) return PICOSAT_UNSATISFIABLE; if (satisfied ()) goto SATISFIED; init_restart (); isimplify = fixed; backtracked = 0; for (;;) { if (!conflict) bcp (); if (conflict) { incincs (); backtrack (); if (mtcls) return PICOSAT_UNSATISFIABLE; backtracked = 1; continue; } if (satisfied ()) { SATISFIED: #ifndef NDEBUG original_clauses_satisfied (); assumptions_satisfied (); #endif return PICOSAT_SATISFIABLE; } if (backtracked) { backtracked = 0; if (!level && isimplify < fixed) iteration (); } if (l >= 0 && count >= l) /* decision limit reached ? */ return PICOSAT_UNKNOWN; if (propagations >= lpropagations)/* propagation limit reached ? */ return PICOSAT_UNKNOWN; #ifndef NADC if (!adodisabled && adoconflicts >= adoconflictlimit) { assert (bcp_queue_is_empty ()); return PICOSAT_UNKNOWN; } #endif if (fsimplify < fixed && lsimplify <= propagations) { simplify (); if (!bcp_queue_is_empty ()) continue; #ifndef NFL if (mtcls) return PICOSAT_UNSATISFIABLE; if (satisfied ()) return PICOSAT_SATISFIABLE; assert (!level); #endif } if (!lreduce) init_reduce (); if (need_to_reduce ()) reduce (50); if (conflicts >= lrestart && level > 2) restart (); decide (); if (failed_assumption) return PICOSAT_UNSATISFIABLE; count++; } } static void rebias (void) { Cls ** p, * c; Var * v; for (v = vars + 1; v <= vars + max_var; v++) v->assigned = 0; memset (jwh, 0, 2 * (max_var + 1) * sizeof *jwh); for (p = oclauses; p < ohead; p++) { c = *p; if (!c) continue; if (c->learned) continue; incjwh (c); } } #ifdef TRACE static unsigned core (void) { unsigned idx, prev, this, delta, i, lcore, vcore; unsigned *stack, *shead, *eos; Lit **q, **eol, *lit; Cls *cls, *reason; Znt *p, byte; Zhn *zhain; Var *v; assert (trace); assert (mtcls || failed_assumption); if (ocore >= 0) return ocore; lcore = ocore = vcore = 0; stack = shead = eos = 0; ENLARGE (stack, shead, eos); if (mtcls) { idx = CLS2IDX (mtcls); *shead++ = idx; } else { assert (failed_assumption); v = LIT2VAR (failed_assumption); reason = v->reason; assert (reason); idx = CLS2IDX (reason); *shead++ = idx; } while (shead > stack) { idx = *--shead; zhain = IDX2ZHN (idx); if (zhain) { if (zhain->core) continue; zhain->core = 1; lcore++; cls = IDX2CLS (idx); if (cls) { assert (!cls->core); cls->core = 1; } i = 0; delta = 0; prev = 0; for (p = zhain->znt; (byte = *p); p++, i += 7) { delta |= (byte & 0x7f) << i; if (byte & 0x80) continue; this = prev + delta; assert (prev < this); /* no overflow */ if (shead == eos) ENLARGE (stack, shead, eos); *shead++ = this; prev = this; delta = 0; i = -7; } } else { cls = IDX2CLS (idx); assert (cls); assert (!cls->learned); if (cls->core) continue; cls->core = 1; ocore++; eol = end_of_lits (cls); for (q = cls->lits; q < eol; q++) { lit = *q; v = LIT2VAR (lit); if (v->core) continue; v->core = 1; vcore++; if (!failed_assumption) continue; if (lit != failed_assumption) continue; reason = v->reason; if (!reason) continue; if (reason->core) continue; idx = CLS2IDX (reason); if (shead == eos) ENLARGE (stack, shead, eos); *shead++ = idx; } } } DELETEN (stack, eos - stack); if (verbosity) fprintf (out, "%s%u core variables out of %u (%.1f%%)\n" "%s%u core original clauses out of %u (%.1f%%)\n" "%s%u core learned clauses out of %u (%.1f%%)\n", prefix, vcore, max_var, PERCENT (vcore, max_var), prefix, ocore, oadded, PERCENT (ocore, oadded), prefix, lcore, ladded, PERCENT (lcore, ladded)); return ocore; } static void write_unsigned (unsigned d, FILE * file) { static char write_unsigned_buffer[20]; unsigned tmp; char * res; assert (sizeof d <= 4); res = write_unsigned_buffer + sizeof write_unsigned_buffer; *--res = 0; tmp = d; do { assert (res > write_unsigned_buffer); *--res = '0' + (tmp % 10); tmp /= 10; } while (tmp); fputs (res, file); } static void trace_lits (Cls * cls, FILE * file) { Lit **p, **eol = end_of_lits (cls); assert (cls); assert (cls->core); for (p = cls->lits; p < eol; p++) { write_int (LIT2INT (*p), file); fputc (' ', file); } fputc ('0', file); } static void write_idx (unsigned idx, FILE * file) { write_unsigned (EXPORTIDX (idx), file); } static void trace_clause (unsigned idx, Cls * cls, FILE * file, int fmt) { assert (cls); assert (cls->core); assert (fmt == RUP_TRACE_FMT || !cls->learned); assert (CLS2IDX (cls) == idx); if (fmt != RUP_TRACE_FMT) { write_idx (idx, file); fputc (' ', file); } trace_lits (cls, file); if (fmt != RUP_TRACE_FMT) fputs (" 0", file); fputc ('\n', file); } static void trace_zhain (unsigned idx, Zhn * zhain, FILE * file, int fmt) { unsigned prev, this, delta, i; Znt *p, byte; Cls * cls; assert (zhain); assert (zhain->core); write_idx (idx, file); fputc (' ', file); if (fmt == EXTENDED_TRACECHECK_TRACE_FMT) { cls = IDX2CLS (idx); assert (cls); trace_lits (cls, file); } else { assert (fmt == COMPACT_TRACECHECK_TRACE_FMT); putc ('*', file); } i = 0; delta = 0; prev = 0; for (p = zhain->znt; (byte = *p); p++, i += 7) { delta |= (byte & 0x7f) << i; if (byte & 0x80) continue; this = prev + delta; putc (' ', file); write_idx (this, file); prev = this; delta = 0; i = -7; } fputs (" 0\n", file); } static void write_core (FILE * file) { Lit **q, **eol; Cls **p, *cls; fprintf (file, "p cnf %u %u\n", max_var, core ()); for (p = SOC; p != EOC; p = NXC (p)) { cls = *p; if (!cls || cls->learned || !cls->core) continue; eol = end_of_lits (cls); for (q = cls->lits; q < eol; q++) { write_int (LIT2INT (*q), file); fputc (' ', file); } fputs ("0\n", file); } } #endif static void write_trace (FILE * file, int fmt) { #ifdef TRACE Cls *cls, ** p; Zhn *zhain; unsigned i; core (); if (fmt == RUP_TRACE_FMT) { rupvariables = picosat_variables (), rupclauses = picosat_added_original_clauses (); write_rup_header (file); } for (p = SOC; p != EOC; p = NXC (p)) { cls = *p; if (oclauses <= p && p < eoo) { i = OIDX2IDX (p - oclauses); assert (!cls || CLS2IDX (cls) == i); } else { assert (lclauses <= p && p < eol); i = LIDX2IDX (p - lclauses); } zhain = IDX2ZHN (i); if (zhain) { if (zhain->core) { if (fmt == RUP_TRACE_FMT) trace_clause (i, cls, file, fmt); else trace_zhain (i, zhain, file, fmt); } } else if (cls) { if (fmt != RUP_TRACE_FMT && cls) { if (cls->core) trace_clause (i, cls, file, fmt); } } } #else (void) file; (void) fmt; #endif } static void write_core_wrapper (FILE * file, int fmt) { (void) fmt; #ifdef TRACE write_core (file); #else (void) file; #endif } static Lit * import_lit (int lit) { ABORTIF (lit == INT_MIN, "API usage: INT_MIN literal"); while (abs (lit) > (int) max_var) inc_max_var (); return int2lit (lit); } #ifdef TRACE static void reset_core (void) { Cls ** p, * c; Zhn ** q, * z; unsigned i; for (i = 1; i <= max_var; i++) vars[i].core = 0; for (p = SOC; p != EOC; p = NXC (p)) if ((c = *p)) c->core = 0; for (q = zhains; q != zhead; q++) if ((z = *q)) z->core = 0; ocore = -1; } #endif static void reset_assumptions (void) { Lit ** p; failed_assumption = 0; if (extracted_all_failed_assumptions) { for (p = als; p < alshead; p++) LIT2VAR (*p)->failed = 0; extracted_all_failed_assumptions = 0; } alstail = alshead = als; adecidelevel = 0; } static void check_ready (void) { ABORTIF (state == RESET, "API usage: uninitialized"); } static void check_sat_state (void) { ABORTIF (state != SAT, "API usage: expected to be in SAT state"); } static void check_unsat_state (void) { ABORTIF (state != UNSAT, "API usage: expected to be in UNSAT state"); } static void check_sat_or_unsat_or_unknown_state (void) { ABORTIF (state != SAT && state != UNSAT && state != UNKNOWN, "API usage: expected to be in SAT, UNSAT, or UNKNOWN state"); } static void reset_incremental_usage (void) { unsigned num_non_false; Lit * lit, ** q; check_sat_or_unsat_or_unknown_state (); LOG (fprintf (out, "%sRESET incremental usage\n", prefix)); if (level) undo (0); reset_assumptions (); if (conflict) { num_non_false = 0; for (q = conflict->lits; q < end_of_lits (conflict); q++) { lit = *q; if (lit->val != FALSE) num_non_false++; } // assert (num_non_false >= 2); // TODO: why this assertion? #ifdef NO_BINARY_CLAUSES if (conflict == &cimpl) resetcimpl (); #endif #ifndef NADC if (conflict == adoconflict) resetadoconflict (); #endif conflict = 0; } #ifdef TRACE reset_core (); #endif saved_flips = flips; min_flipped = UINT_MAX; saved_max_var = max_var; state = READY; } static void enter (void) { if (nentered++) return; check_ready (); entered = picosat_time_stamp (); } static void leave (void) { assert (nentered); if (--nentered) return; sflush (); } static void check_trace_support_and_execute (FILE * file, void (*f)(FILE*,int), int fmt) { check_ready (); check_unsat_state (); #ifdef TRACE ABORTIF (!trace, "API usage: tracing disabled"); enter (); f (file, fmt); leave (); #else (void) file; (void) fmt; (void) f; ABORT ("compiled without trace support"); #endif } static void extract_all_failed_assumptions (void) { Lit ** p, ** eol; Var * v, * u; int pos; Cls * c; assert (!extracted_all_failed_assumptions); assert (failed_assumption); assert (mhead == marked); if (marked == eom) ENLARGE (marked, mhead, eom); v = LIT2VAR (failed_assumption); mark_var (v); pos = 0; while (pos < mhead - marked) { v = marked[pos++]; assert (v->mark); c = var2reason (v); if (!c) continue; eol = end_of_lits (c); for (p = c->lits; p < eol; p++) { u = LIT2VAR (*p); if (!u->mark) mark_var (u); } } for (p = als; p < alshead; p++) { u = LIT2VAR (*p); if (!u->mark) continue; u->failed = 1; LOG (fprintf (out, "%sfailed assumption %d\n", prefix, lit2int (*p))); } while (mhead > marked) (*--mhead)->mark = 0; extracted_all_failed_assumptions = 1; } const char * picosat_copyright (void) { return "Copyright (c) 2006 - 2010 Armin Biere JKU Linz"; } void picosat_init (void) { init (); } void picosat_adjust (int new_max_var) { unsigned new_size_vars; enter (); new_max_var = abs (new_max_var); new_size_vars = new_max_var + 1; if (size_vars < new_size_vars) enlarge (new_size_vars); while (max_var < (unsigned) new_max_var) inc_max_var (); leave (); } int picosat_inc_max_var (void) { if (measurealltimeinlib) enter (); else check_ready (); inc_max_var (); if (measurealltimeinlib) leave (); return max_var; } void picosat_set_verbosity (int new_verbosity_level) { check_ready (); verbosity = new_verbosity_level; } int picosat_enable_trace_generation (void) { int res = 0; check_ready (); #ifdef TRACE ABORTIF (addedclauses, "API usage: trace generation enabled after adding clauses"); res = trace = 1; #endif return res; } void picosat_set_incremental_rup_file (FILE * rup_file, int m, int n) { check_ready (); assert (!rupstarted); rup = rup_file; rupvariables = m; rupclauses = n; } void picosat_set_output (FILE * output_file) { check_ready (); out = output_file; } void picosat_measure_all_calls (void) { check_ready (); measurealltimeinlib = 1; } void picosat_set_prefix (const char * str) { check_ready (); new_prefix (str); } void picosat_set_seed (unsigned s) { check_ready (); srng = s; } void picosat_reset (void) { check_ready (); reset (); } int picosat_add (int int_lit) { int res = oadded; Lit *lit; if (measurealltimeinlib) enter (); else check_ready (); ABORTIF (rup && rupstarted && oadded >= (unsigned)rupclauses, "API usage: adding too many clauses after RUP header written"); #ifndef NADC ABORTIF (addingtoado, "API usage: 'picosat_add' and 'picosat_add_ado_lit' mixed"); #endif if (state != READY) reset_incremental_usage (); lit = import_lit (int_lit); if (int_lit) add_lit (lit); else simplify_and_add_original_clause (); if (measurealltimeinlib) leave (); return res; } void picosat_add_ado_lit (int external_lit) { #ifndef NADC Lit * internal_lit; if (measurealltimeinlib) enter (); else check_ready (); if (state != READY) reset_incremental_usage (); ABORTIF (!addingtoado && ahead > added, "API usage: 'picosat_add' and 'picosat_add_ado_lit' mixed"); if (external_lit) { addingtoado = 1; internal_lit = import_lit (external_lit); add_lit (internal_lit); } else { addingtoado = 0; add_ado (); } if (measurealltimeinlib) leave (); #else (void) external_lit; ABORT ("compiled without all different constraint support"); #endif } void picosat_assume (int int_lit) { Lit *lit; if (measurealltimeinlib) enter (); else check_ready (); if (state != READY) reset_incremental_usage (); lit = import_lit (int_lit); if (alshead == eoals) { assert (alstail == als); ENLARGE (als, alshead, eoals); alstail = als; } *alshead++ = lit; LOG (fprintf (out, "%sassumption %d\n", prefix, int_lit)); if (measurealltimeinlib) leave (); } int picosat_sat (int l) { int res; char ch; enter (); calls++; LOG (fprintf (out, "%sSTART call %u\n", prefix, calls)); if (added < ahead) { #ifndef NADC if (addingtoado) ABORT ("API usage: incomplete all different constraint"); else #endif ABORT ("API usage: incomplete clause"); } if (state != READY) reset_incremental_usage (); res = sat (l); assert (state == READY); switch (res) { case PICOSAT_UNSATISFIABLE: ch = '0'; state = UNSAT; break; case PICOSAT_SATISFIABLE: ch = '1'; state = SAT; break; default: ch = '?'; state = UNKNOWN; break; } if (verbosity) { report (1, ch); rheader (); } leave (); LOG (fprintf (out, "%sEND call %u\n", prefix, calls)); last_sat_call_result = res; return res; } int picosat_res (void) { return last_sat_call_result; } int picosat_deref (int int_lit) { Lit *lit; check_ready (); check_sat_state (); ABORTIF (!int_lit, "API usage: can not deref zero literal"); ABORTIF (mtcls, "API usage: deref after empty clause generated"); #ifdef STATS derefs++; #endif if (abs (int_lit) > (int) max_var) return 0; lit = int2lit (int_lit); if (lit->val == TRUE) return 1; if (lit->val == FALSE) return -1; return 0; } int picosat_deref_toplevel (int int_lit) { Lit *lit; Var * v; check_ready (); ABORTIF (!int_lit, "API usage: can not deref zero literal"); ABORTIF (mtcls, "API usage: deref after empty clause generated"); #ifdef STATS derefs++; #endif if (abs (int_lit) > (int) max_var) return 0; lit = int2lit (int_lit); v = LIT2VAR (lit); if (v->level > 0) return 0; if (lit->val == TRUE) return 1; if (lit->val == FALSE) return -1; return 0; } int picosat_inconsistent (void) { check_ready (); return mtcls != 0; } int picosat_corelit (int int_lit) { int res; check_ready (); check_unsat_state (); ABORTIF (!int_lit, "API usage: zero literal can not be in core"); assert (mtcls || failed_assumption); res = 0; #ifdef TRACE { ABORTIF (!trace, "tracing disabled"); if (measurealltimeinlib) enter (); core (); if (abs (int_lit) <= (int) max_var) res = vars[abs (int_lit)].core; assert (!res || failed_assumption || vars[abs (int_lit)].used); if (measurealltimeinlib) leave (); } #else ABORT ("compiled without trace support"); #endif return res; } int picosat_coreclause (int ocls) { int res; check_ready (); check_unsat_state (); ABORTIF (ocls < 0, "API usage: negative original clause index"); ABORTIF (ocls >= (int)oadded, "API usage: original clause index exceeded"); assert (mtcls || failed_assumption); res = 0; #ifdef TRACE { Cls ** clsptr, * cls; ABORTIF (!trace, "tracing disabled"); if (measurealltimeinlib) enter (); core (); clsptr = oclauses + ocls; assert (clsptr < ohead); cls = *clsptr; if (cls) res = cls->core; if (measurealltimeinlib) leave (); } #else ABORT ("compiled without trace support"); #endif return res; } int picosat_failed_assumption (int int_lit) { Lit * lit; Var * v; ABORTIF (!int_lit, "API usage: zero literal as assumption"); check_ready (); check_unsat_state (); if (mtcls) return 0; assert (failed_assumption); if (abs (int_lit) > (int) max_var) return 0; if (!extracted_all_failed_assumptions) extract_all_failed_assumptions (); lit = import_lit (int_lit); v = LIT2VAR (lit); return v->failed; } const int * picosat_failed_assumptions (void) { Lit ** p, * lit; Var * v; int ilit; falshead = fals; check_ready (); check_unsat_state (); if (!mtcls) { assert (failed_assumption); if (!extracted_all_failed_assumptions) extract_all_failed_assumptions (); for (p = als; p < alshead; p++) { lit = *p; v = LIT2VAR (*p); if (!v->failed) continue; ilit = LIT2INT (lit); if (falshead == eofals) ENLARGE (fals, falshead, eofals); *falshead++ = ilit; } } if (falshead == eofals) ENLARGE (fals, falshead, eofals); *falshead++ = 0; return fals; } static const char * enumstr (int i) { int last = i % 10; if (last == 1) return "st"; if (last == 2) return "nd"; if (last == 3) return "rd"; return "th"; } const int * picosat_mus_assumptions (void * s, void (*cb)(void*,const int*), int fix) { int i, j, ilit, len, oldlen, norig = alshead - als, nwork, * work, res; signed char * redundant; Lit ** p, * lit; int failed; Var * v; check_ready (); check_unsat_state (); len = 0; if (!mtcls) { assert (failed_assumption); if (!extracted_all_failed_assumptions) extract_all_failed_assumptions (); for (p = als; p < alshead; p++) if (LIT2VAR (*p)->failed) len++; } if (mass) DELETEN (mass, szmass); szmass = len + 1; NEWN (mass, szmass); i = 0; for (p = als; p < alshead; p++) { lit = *p; v = LIT2VAR (lit); if (!v->failed) continue; ilit = LIT2INT (lit); assert (i < len); mass[i++] = ilit; } assert (i == len); mass[i] = 0; if (verbosity) fprintf (out, "%sinitial set of failed assumptions of size %d out of %d (%.0f%%)\n", prefix, len, norig, PERCENT (len, norig)); if (cb) cb (s, mass); nwork = len; NEWN (work, nwork); for (i = 0; i < len; i++) work[i] = mass[i]; NEWN (redundant, nwork); CLRN (redundant, nwork); for (i = 0; i < nwork; i++) { if (redundant[i]) continue; if (verbosity > 1) fprintf (out, "%strying to drop %d%s assumption %d\n", prefix, i, enumstr (i), work[i]); for (j = 0; j < nwork; j++) if (i != j && !redundant[j]) picosat_assume (work[j]); res = picosat_sat (-1); if (res == 10) { if (verbosity > 1) fprintf (out, "%sfailed to drop %d%s assumption %d\n", prefix, i, enumstr (i), work[i]); if (fix) { picosat_add (work[i]); picosat_add (0); } } else { assert (res == 20); if (verbosity > 1) fprintf (out, "%ssuceeded to drop %d%s assumption %d\n", prefix, i, enumstr (i), work[i]); redundant[i] = 1; for (j = 0; j < nwork; j++) { failed = picosat_failed_assumption (work[j]); if (j <= i) { assert (redundant[j] == !failed); continue; } if (!failed) { redundant[j] = -1; if (verbosity > 1) fprintf (out, "%salso suceeded to drop %d%s assumption %d\n", prefix, j, enumstr (j), work[j]); } } oldlen = len; len = 0; for (j = 0; j < nwork; j++) if (!redundant[j]) mass[len++] = work[j]; mass[len] = 0; assert (len < oldlen); if (fix) { picosat_add (-work[i]); picosat_add (0); } #ifndef NDEBUG for (j = 0; j <= i; j++) assert (redundant[j] >= 0); #endif for (j = i + 1; j < nwork; j++) { if (redundant[j] >= 0) continue; if (fix) { picosat_add (-work[j]); picosat_add (0); } redundant[j] = 1; } if (verbosity) fprintf (out, "%sreduced set of failed assumptions of size %d out of %d (%.0f%%)\n", prefix, len, norig, PERCENT (len, norig)); if (cb) cb (s, mass); } } DELETEN (work, nwork); DELETEN (redundant, nwork); if (verbosity) fprintf (out, "%sreinitializaing unsat state", prefix); for (i = 0; i < len; i++) picosat_assume (mass[i]); res = picosat_sat (-1); assert (res == 20); return mass; } int picosat_usedlit (int int_lit) { int res; check_ready (); check_sat_or_unsat_or_unknown_state (); ABORTIF (!int_lit, "API usage: zero literal can not be used"); int_lit = abs (int_lit); res = (int_lit <= (int) max_var) ? vars[int_lit].used : 0; return res; } void picosat_write_clausal_core (FILE * file) { check_trace_support_and_execute (file, write_core_wrapper, 0); } void picosat_write_compact_trace (FILE * file) { check_trace_support_and_execute (file, write_trace, COMPACT_TRACECHECK_TRACE_FMT); } void picosat_write_extended_trace (FILE * file) { check_trace_support_and_execute (file, write_trace, EXTENDED_TRACECHECK_TRACE_FMT); } void picosat_write_rup_trace (FILE * file) { check_trace_support_and_execute (file, write_trace, RUP_TRACE_FMT); } size_t picosat_max_bytes_allocated (void) { check_ready (); return max_bytes; } void picosat_set_propagation_limit (unsigned long long l) { lpropagations = l; } unsigned long long picosat_propagations (void) { return propagations; } int picosat_variables (void) { check_ready (); return (int) max_var; } int picosat_added_original_clauses (void) { check_ready (); return (int) oadded; } void picosat_stats (void) { unsigned redlits; #ifdef STATS check_ready (); assert (sdecisions + rdecisions + assumptions == decisions); #endif if (calls > 1) fprintf (out, "%s%u calls\n", prefix, calls); fprintf (out, "%s%u iterations\n", prefix, iterations); fprintf (out, "%s%u restarts", prefix, restarts); #ifdef STATS fprintf (out, " (%u skipped)", skippedrestarts); #endif fputc ('\n', out); #ifndef NFL fprintf (out, "%s%u failed literals", prefix, failedlits); #ifdef STATS fprintf (out, ", %u calls, %u rounds, %llu propagations", flcalls, flrounds, flprops); #endif fputc ('\n', out); #ifdef STATS fprintf (out, "%sfl: %u = %.1f%% implicit, %llu oopsed, %llu tried, %llu skipped\n", prefix, ifailedlits, PERCENT (ifailedlits, failedlits), floopsed, fltried, flskipped); #endif #endif fprintf (out, "%s%u conflicts", prefix, conflicts); #ifdef STATS fprintf (out, " (%u uips = %.1f%%)\n", uips, PERCENT(uips,conflicts)); #else fputc ('\n', out); #endif #ifndef NADC fprintf (out, "%s%u adc conflicts\n", prefix, adoconflicts); #endif #ifdef STATS fprintf (out, "%s%llu dereferenced literals\n", prefix, derefs); #endif fprintf (out, "%s%u decisions", prefix, decisions); #ifdef STATS fprintf (out, " (%u random = %.2f%%", rdecisions, PERCENT (rdecisions, decisions)); fprintf (out, ", %u assumptions", assumptions); fputc (')', out); #endif fputc ('\n', out); #ifdef STATS fprintf (out, "%s%u static phase decisions (%.1f%% of all variables)\n", prefix, staticphasedecisions, PERCENT (staticphasedecisions, max_var)); #endif fprintf (out, "%s%u fixed variables\n", prefix, fixed); assert (nonminimizedllits >= minimizedllits); redlits = nonminimizedllits - minimizedllits; fprintf (out, "%s%u learned literals\n", prefix, llitsadded); fprintf (out, "%s%.1f%% deleted literals\n", prefix, PERCENT (redlits, nonminimizedllits)); #ifdef STATS #ifndef NO_BINARY_CLAUSES fprintf (out, "%s%llu antecedents (%.1f antecedents per clause", prefix, antecedents, AVERAGE (antecedents, conflicts)); #endif #ifdef TRACE if (trace) fprintf (out, ", %.1f bytes/antecedent)", AVERAGE (znts, antecedents)); #endif #if !defined(NO_BINARY_CLAUSES) || defined(TRACE) fputs (")\n", out); #endif fprintf (out, "%s%llu propagations (%.1f propagations per decision)\n", prefix, propagations, AVERAGE (propagations, decisions)); fprintf (out, "%s%llu visits (%.1f per propagation)\n", prefix, visits, AVERAGE (visits, propagations)); fprintf (out, "%s%llu binary clauses visited (%.1f%% %.1f per propagation)\n", prefix, bvisits, PERCENT (bvisits, visits), AVERAGE (bvisits, propagations)); fprintf (out, "%s%llu ternary clauses visited (%.1f%% %.1f per propagation)\n", prefix, tvisits, PERCENT (tvisits, visits), AVERAGE (tvisits, propagations)); fprintf (out, "%s%llu large clauses visited (%.1f%% %.1f per propagation)\n", prefix, lvisits, PERCENT (lvisits, visits), AVERAGE (lvisits, propagations)); fprintf (out, "%s%llu other true (%.1f%% of visited clauses)\n", prefix, othertrue, PERCENT (othertrue, visits)); fprintf (out, "%s%llu other true in binary clauses (%.1f%%)" ", %llu upper (%.1f%%)\n", prefix, othertrue2, PERCENT (othertrue2, othertrue), othertrue2u, PERCENT (othertrue2u, othertrue2)); fprintf (out, "%s%llu other true in large clauses (%.1f%%)" ", %llu upper (%.1f%%)\n", prefix, othertruel, PERCENT (othertruel, othertrue), othertruelu, PERCENT (othertruelu, othertruel)); fprintf (out, "%s%llu ternary and large traversals (%.1f per visit)\n", prefix, traversals, AVERAGE (traversals, visits)); fprintf (out, "%s%llu large traversals (%.1f per large visit)\n", prefix, ltraversals, AVERAGE (ltraversals, lvisits)); fprintf (out, "%s%llu assignments\n", prefix, assignments); #else fprintf (out, "%s%llu propagations\n", prefix, picosat_propagations ()); #endif fprintf (out, "%s%.1f%% variables used\n", prefix, PERCENT (vused, max_var)); sflush (); fprintf (out, "%s%.1f seconds in library\n", prefix, seconds); fprintf (out, "%s%.1f megaprops/second\n", prefix, AVERAGE (propagations / 1e6f, seconds)); #ifdef STATS fprintf (out, "%s%.1f million visits per second\n", prefix, AVERAGE (visits / 1e6f, seconds)); fprintf (out, "%srecycled %.1f MB in %u reductions\n", prefix, rrecycled / (double) (1 << 20), reductions); fprintf (out, "%srecycled %.1f MB in %u simplifications\n", prefix, srecycled / (double) (1 << 20), simps); #else fprintf (out, "%s%u simplifications\n", prefix, simps); fprintf (out, "%s%u reductions\n", prefix, reductions); fprintf (out, "%s%.1f MB recycled\n", prefix, recycled / (double) (1 << 20)); #endif fprintf (out, "%s%.1f MB maximally allocated\n", prefix, picosat_max_bytes_allocated () / (double) (1 << 20)); } #ifndef NGETRUSAGE #include #include #include #endif double picosat_time_stamp (void) { double res = -1; #ifndef NGETRUSAGE struct rusage u; res = 0; if (!getrusage (RUSAGE_SELF, &u)) { res += u.ru_utime.tv_sec + 1e-6 * u.ru_utime.tv_usec; res += u.ru_stime.tv_sec + 1e-6 * u.ru_stime.tv_usec; } #endif return res; } double picosat_seconds (void) { check_ready (); return seconds; } void picosat_print (FILE * file) { #ifdef NO_BINARY_CLAUSES Lit * lit, *other, * last; Ltk * stack; #endif Lit **q, **eol; Cls **p, *cls; unsigned n; if (measurealltimeinlib) enter (); else check_ready (); n = 0; n += alshead - als; for (p = SOC; p != EOC; p = NXC (p)) { cls = *p; if (!cls) continue; #ifdef TRACE if (cls->collected) continue; #endif n++; } #ifdef NO_BINARY_CLAUSES last = int2lit (-max_var); for (lit = int2lit (1); lit <= last; lit++) { stack = LIT2IMPLS (lit); eol = stack->start + stack->count; for (q = stack->start; q < eol; q++) if (*q >= lit) n++; } #endif fprintf (file, "p cnf %d %u\n", max_var, n); for (p = SOC; p != EOC; p = NXC (p)) { cls = *p; if (!cls) continue; #ifdef TRACE if (cls->collected) continue; #endif eol = end_of_lits (cls); for (q = cls->lits; q < eol; q++) { write_int (lit2int (*q), file); fputc (' ', file); } fputs ("0\n", file); } #ifdef NO_BINARY_CLAUSES last = int2lit (-max_var); for (lit = int2lit (1); lit <= last; lit++) { stack = LIT2IMPLS (lit); eol = stack->start + stack->count; for (q = stack->start; q < eol; q++) if ((other = *q) >= lit) fprintf (file, "%d %d 0\n", lit2int (lit), lit2int (other)); } #endif { Lit **r; for (r = als; r < alshead; r++) fprintf (file, "%d 0\n", lit2int (*r)); } fflush (file); if (measurealltimeinlib) leave (); } void picosat_enter (void) { enter (); } void picosat_leave (void) { leave (); } void picosat_message (int level, const char * fmt, ...) { va_list ap; if (level > verbosity) return; fputs (prefix, out); va_start (ap, fmt); vfprintf (out, fmt, ap); va_end (ap); fputc ('\n', out); } int picosat_changed (void) { int res; check_ready (); check_sat_state (); res = (min_flipped <= saved_max_var); assert (!res || saved_flips != flips); return res; } static void setemgr (void * nmgr) { ABORTIF (emgr && emgr != nmgr, "API usage: mismatched external memory managers"); emgr = nmgr; } void picosat_set_new (void * nmgr, void * (*nnew)(void*,size_t)) { ABORTIF (state != RESET, "API usage: 'picosat_set_new' after 'picosat_init'"); enew = nnew; setemgr (nmgr); } void picosat_set_resize (void * nmgr, void * (*nresize)(void*,void*,size_t,size_t)) { ABORTIF (state != RESET, "API usage: 'picosat_set_resize' after 'picosat_init'"); eresize = nresize; setemgr (nmgr); } void picosat_set_delete (void * nmgr, void (*ndelete)(void*,void*,size_t)) { ABORTIF (state != RESET, "API usage: 'picosat_set_delete' after 'picosat_init'"); edelete = ndelete; setemgr (nmgr); } void picosat_reset_phases (void) { rebias (); } void picosat_reset_scores (void) { Rnk * r; hhead = heap + 1; for (r = rnks + 1; r <= rnks + max_var; r++) { CLR (r); hpush (r); } } void picosat_remove_learned (unsigned percentage) { reset_incremental_usage (); reduce (percentage); } void picosat_set_global_default_phase (int phase) { check_ready (); ABORTIF (phase < 0, "API usage: 'picosat_set_global_default_phase' " "with negative argument"); ABORTIF (phase > 3, "API usage: 'picosat_set_global_default_phase' " "with argument > 3"); defaultphase = phase; } void picosat_set_default_phase_lit (int int_lit, int phase) { unsigned newphase; Lit * lit; Var * v; check_ready (); lit = import_lit (int_lit); v = LIT2VAR (lit); if (phase) { newphase = (int_lit < 0) == (phase < 0); v->phase = newphase; v->assigned = 1; } else v->assigned = 0; } void picosat_set_more_important_lit (int int_lit) { Lit * lit; Var * v; Rnk * r; check_ready (); lit = import_lit (int_lit); v = LIT2VAR (lit); r = VAR2RNK (v); ABORTIF (r->lessimportant, "can not mark variable more and less important"); if (r->moreimportant) return; r->moreimportant = 1; if (r->pos) hup (r); } void picosat_set_less_important_lit (int int_lit) { Lit * lit; Var * v; Rnk * r; check_ready (); lit = import_lit (int_lit); v = LIT2VAR (lit); r = VAR2RNK (v); ABORTIF (r->moreimportant, "can not mark variable more and less important"); if (r->lessimportant) return; r->lessimportant = 1; if (r->pos) hup (r); } #ifndef NADC unsigned picosat_ado_conflicts (void) { check_ready (); return adoconflicts; } void picosat_disable_ado (void) { check_ready (); assert (!adodisabled); adodisabled = 1; } void picosat_enable_ado (void) { check_ready (); assert (adodisabled); adodisabled = 0; } void picosat_set_ado_conflict_limit (unsigned newadoconflictlimit) { check_ready (); adoconflictlimit = newadoconflictlimit; } #endif int picosat_haveados (void) { #ifndef NADC return 1; #else return 0; #endif }