Files
psat/cnf.c
2022-07-17 14:03:47 -04:00

295 lines
8.4 KiB
C

#include "cnf.h"
cnf* readDIMACS(char* path) {
cnf* c = malloc(sizeof(cnf));
CHECK(c, "Failed to alloc CNF struct\n");
FILE* f = fopen(path, "r");
CHECK(f, "Failed to open file\n");
u32 bufsize = 1000;
char* buf = malloc(sizeof(char) * bufsize);
CHECK(buf, "Failed to alloc read buffer\n");
CHECK(fgets(buf, sizeof(char) * bufsize, f), "Failed to read file\n");
while (buf[0] == 'c') {
CHECK(fgets(buf, sizeof(char) * bufsize, f), "Failed to read file\n");
}
char* temp = buf;
while (*temp == ' ' || *temp == 'p' || *temp == 'c' || *temp == 'n' || *temp == 'f') {
temp++;
}
c->varcnt = 0;
while (((u8) (*temp - '0')) < 10) {
c->varcnt *= 10;
c->varcnt += (*temp - '0');
temp++;
}
while (*temp == ' ') temp++;
c->clausecnt = 0;
while (((u8) (*temp - '0')) < 10) {
c->clausecnt *= 10;
c->clausecnt += (*temp - '0');
temp++;
}
u32 nsize = sizeof(char) * (c->varcnt * 12LU) + 10;
char* nbuf = realloc(buf, nsize);
CHECK(nbuf, "Failed to realloc read buffer\n");
buf = nbuf;
u32 cnt = 0;
u32 cap = 32;
c->variables = calloc( cap, sizeof(u32));
CHECK(c->variables, "Failed to allocate literal variables\n");
c->clauses = calloc( cap, sizeof(u32));
CHECK(c->clauses, "Failed to allocate literal clauses\n");
c->pars = calloc( cap, sizeof(u8));
CHECK(c->pars, "Failed to allocate literal parities\n");
c->lastvars = calloc( c->clausecnt, sizeof(u32));
CHECK(c->lastvars, "Failed to allocate clause lastvars\n");
for (u32 i = 0; i < c->clausecnt; ++i) {
CHECK(fgets(buf, nsize, f), "Failed to read clause\n");
temp = buf;
while (*temp == ' ') temp++;
bool empty = true;
bool tr = true;
while (*temp != '\n') {
if (cnt == cap) {
u32 ncap = cap << 1U;
c->variables = realloc(c->variables, sizeof(u32) * ncap);
memset(c->variables + cap, 0, sizeof(u32) * cap);
CHECK(c->variables, "Failed to realloc variable array\n");
c->clauses = realloc(c->clauses, sizeof(u32) * ncap);
memset(c->clauses + cap, 0, sizeof(u32) * cap);
CHECK(c->clauses, "Failed to realloc clause array\n");
c->pars = realloc(c->pars, sizeof(u8) * ncap);
memset(c->pars + cap, 0, sizeof(u8) * cap);
CHECK(c->pars, "Failed to realloc parity array\n");
cap = ncap;
}
if (*temp == '-') {
tr = false;
} else if (((u8) (*temp - '0')) < 10) {
c->variables[cnt] *= 10;
c->variables[cnt] += (*temp - '0');
} else {
while (temp[1] == ' ') temp++;
c->pars[cnt] = tr;
c->clauses[cnt] = i;
c->variables[cnt] -= 1;
if (c->lastvars[i] < c->variables[cnt]) c->lastvars[i] = c->variables[cnt];
empty = false;
tr = true;
cnt++;
if (temp[1] == '0') {
break;
}
}
temp++;
}
if (empty) {
printf("UNSAT: Empty clause %u\n", i);
return NULL;
}
}
for (u32 i = 0; i < c->clausecnt; ++i) {
c->lastvars[i] += 1U;
c->lastvars[i] = c->varcnt - c->lastvars[i];
}
c->litcnt = cnt;
c->variables = realloc(c->variables, sizeof(u32) * c->litcnt);
c->clauses = realloc(c->clauses, sizeof(u32) * c->litcnt);
c->pars = realloc(c->pars, sizeof(u8) * c->litcnt);
free(buf);
if (fclose(f)) {
printf("Failed to close file\n");
return NULL;
}
return c;
}
void printcnf(cnf* c) {
printf("p cnf %u %u\n", c->varcnt, c->clausecnt);
u32 pclause = 0;
for (u32 i = 0; i < c->litcnt; ++i) {
if (c->clauses[i] != pclause) printf("0\n");
if (c->pars[i] == 0) printf("-");
printf("%u ", c->variables[i] + 1);
pclause = c->clauses[i];
}
printf("0\n");
}
void freecnf(cnf* c) {
free(c->pars);
free(c->clauses);
free(c->variables);
free(c->lastvars);
free(c);
}
const u64 RBITS = 8;
const u64 RSIZE = 1LU << RBITS;
const u64 RLVLS = (63LU / RBITS) + 1;
const u64 RMASK = RSIZE - 1;
// Currently sorting array of program pointers by the score of the programs
// I need to sort by lastvar, within that sort by clause
void sortlastnum(cnf* c, u64 N) {
bool v = false;
u32* d = malloc(sizeof(u32) * c->litcnt);
u32* d2 = malloc(sizeof(u32) * c->litcnt);
u8* d3 = malloc(sizeof(u8) * c->litcnt);
u64 qb[RLVLS * RSIZE];
u64 qe[RLVLS * RSIZE];
memset(qb, 0, sizeof(u64) * RLVLS * RSIZE);
memset(qe, 0, sizeof(u64) * RLVLS * RSIZE);
for (u64 pass = 0; pass < RLVLS; ++pass) {
u64 shift = pass * RBITS;
for (u64 i = 0; i < N; ++i) {
u32 val = UINT32_MAX - c->lastvars[(c->clausecnt - 1) - c->clauses[i]];
u64 ind = (val >> shift) & RMASK;
qe[pass * RSIZE + ind]++;
}
u64 uc = 0;
for (u64 i = 0; i < RSIZE; ++i) if (qe[pass * RSIZE + i]) uc++;
if (uc == 1) continue;
qb[pass * RSIZE] = 0;
for (u64 i = 1; i < RSIZE; ++i) {
qb[pass * RSIZE + i] = qb[pass * RSIZE + i - 1] + qe[pass * RSIZE + i - 1];
}
for (u64 i = 0; i < N; ++i) {
u32 val = UINT32_MAX - c->lastvars[(c->clausecnt - 1) - c->clauses[i]];
u64 ind = (val >> shift) & RMASK;
d[qb[pass * RSIZE + ind]] = c->variables[i];
d2[qb[pass * RSIZE + ind]] = c->clauses[i];
d3[qb[pass * RSIZE + ind]] = c->pars[i];
qb[pass * RSIZE + ind]++;
__builtin_prefetch(d + qb[pass * RSIZE + ind] + 1);
__builtin_prefetch(d2 + qb[pass * RSIZE + ind] + 1);
__builtin_prefetch(d3 + qb[pass * RSIZE + ind] + 1);
}
u32* tptr = c->variables;
c->variables = d;
d = tptr;
tptr = c->clauses;
c->clauses = d2;
d2 = tptr;
u8* tptr2 = c->pars;
c->pars = d3;
d3 = tptr2;
v = !v;
}
if (v) {
u32* tptr = c->variables;
c->variables = d;
d = tptr;
tptr = c->clauses;
c->clauses = d2;
d2 = tptr;
u8* tptr2 = c->pars;
c->pars = d3;
d3 = tptr2;
memcpy(c->variables, d, N * sizeof(u32));
memcpy(c->clauses, d2, N * sizeof(u32));
memcpy(c->pars, d3, N * sizeof(u8));
}
free(d);
free(d2);
free(d3);
u32* swaparr = malloc(sizeof(u32) * c->clausecnt);
for (u32 i = 0; i < c->clausecnt; ++i) {
swaparr[i] = i;
}
v = false;
d = malloc(sizeof(u32) * c->clausecnt);
memset(qb, 0, sizeof(u64) * RLVLS * RSIZE);
memset(qe, 0, sizeof(u64) * RLVLS * RSIZE);
for (u64 pass = 0; pass < RLVLS; ++pass) {
u64 shift = pass * RBITS;
for (u64 i = 0; i < c->clausecnt; ++i) {
u32 val = UINT32_MAX - c->lastvars[swaparr[i]];
u64 ind = (val >> shift) & RMASK;
qe[pass * RSIZE + ind]++;
}
u64 uc = 0;
for (u64 i = 0; i < RSIZE; ++i) if (qe[pass * RSIZE + i]) uc++;
if (uc == 1) continue;
qb[pass * RSIZE] = 0;
for (u64 i = 1; i < RSIZE; ++i) {
qb[pass * RSIZE + i] = qb[pass * RSIZE + i - 1] + qe[pass * RSIZE + i - 1];
}
for (u64 i = 0; i < c->clausecnt; ++i) {
u32 val = UINT32_MAX - c->lastvars[swaparr[i]];
u64 ind = (val >> shift) & RMASK;
d[qb[pass * RSIZE + ind]] = swaparr[i];
qb[pass * RSIZE + ind]++;
__builtin_prefetch(d + qb[pass * RSIZE + ind] + 1);
}
u32* tptr = swaparr;
swaparr = d;
d = tptr;
v = !v;
}
if (v) {
u32* tptr = swaparr;
swaparr = d;
d = tptr;
memcpy(swaparr, d, c->clausecnt * sizeof(u32));
}
//free(d);
for (uint i = 0; i < c->clausecnt; ++i) {
d[swaparr[i]] = i;
}
for (uint i = 0; i < c->litcnt; ++i) {
c->clauses[i] = d[c->clauses[i]];
}
for (uint i = 0; i < c->clausecnt; ++i) {
swaparr[d[i]] = c->lastvars[i];
}
memcpy(c->lastvars, swaparr, sizeof(u32) * c->clausecnt);
free(swaparr);
free(d);
}