Skip to content

Commit

Permalink
Made table loading more than twice as fast.
Browse files Browse the repository at this point in the history
  • Loading branch information
@rokicki
rokicki committed Oct 7, 2023
1 parent 1f747dc commit 1817310
Show file tree
Hide file tree
Showing 2 changed files with 131 additions and 58 deletions.
175 changes: 122 additions & 53 deletions src/cpp/prunetable.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,7 @@
#else
#define SIGNATURE UNCOMPSIGNATURE
#endif
const int UNPACKBITS = 12; // must be at least 8
fillworker fillworkers[MAXTHREADS];
struct ioqueue ioqueue;
string inputbasename = "unknownpuzzle";
Expand Down Expand Up @@ -286,7 +287,7 @@ prunetable::prunetable(const puzdef &pd, ull maxmem) {
fillcnt = 0;
justread = 0;
for (int i = 0; i < 7; i++)
tabs[i] = 0;
dtabs[i] = 0;
if (!readpt(pd)) {
if (quiet == 0)
cout << "Initializing memory in " << duration() << endl << flush;
Expand Down Expand Up @@ -488,50 +489,82 @@ void prunetable::packblock(ull *mem, ull longcnt, uchar *buf, ull bytecnt) {
if (bytectr != bytecnt)
error("! packing issue 3");
}
void prunetable::unpackblock(ull *mem, ull longcnt, uchar *block, int bytecnt) {
/*
* Define this and use these longer versions if you suspect your
* compiler might not "do the right thing" when doing the pointer
* casts in the technically undefined behavior code below. The first
* one is written carefully to permit the compiler to recognize the
* unaligned load pattern.
*
* For now we go conservative and use the routines that *should* be
* compiled to single instructions (or two instructions for the byteway)
* but might not be, because on the platforms we care about they seem
* to be handled okay.
*/
#define CAREFUL_UNDEFINED
#ifdef CAREFUL_UNDEFINED
static ull getull_swap_unaligned(unsigned char *p) {
return __builtin_bswap64((((ull)p[7]) << 56) + (((ull)p[6]) << 48) +
(((ull)p[5]) << 40) + (((ull)p[4]) << 32) + (((ull)p[3]) << 24) +
(((ull)p[2]) << 16) + (((ull)p[1]) << 8) + (((ull)p[0])));
}
static void setull_unaligned(unsigned char *p, ull v) {
*p = v;
p[1] = v>>8;
p[2] = v>>16;
p[3] = v>>24;
p[4] = v>>32;
p[5] = v>>40;
p[6] = v>>48;
p[7] = v>>56;
}
#else
static ull getull_swap_unaligned(unsigned char *p) {
return __builtin_bswap64(*(ull *)p);
}
static void setull_unaligned(unsigned char *p, ull v) {
*(ull *)p = v;
}
#endif
void prunetable::unpackblock(ull *mem, ull longcnt, uchar *block, int) {
int havebits = 0;
ull accum = 0;
ull bitptr = 0 ;
for (ull i = 0; i < longcnt; i++) {
ull v = 0;
for (int j = 0; j < 8; j++) {
int bitsneeded = 8;
int k = 0;
while (1) {
if (havebits < bitsneeded) {
accum = __builtin_bswap64(*(ull *)(block + (bitptr >> 3))) &
((0xffffffffffffffffULL) >> (bitptr & 7)) ;
havebits = 64 - (bitptr & 7) ;
}
int cp = tabs[k][accum >> (havebits - bitsneeded)];
if (cp >= 0) {
if (cp >= 256) {
if (j != 0)
error("! unexpected high code");
v = cp - 256;
bitptr += codewidths[cp] ;
havebits -= codewidths[cp] ;
accum &= ((1LL << havebits) - 1);
goto setval;
} else {
v += ((ull)cp) << (8 * j);
bitptr += codewidths[cp] ;
havebits -= codewidths[cp] ;
accum &= ((1LL << havebits) - 1);
break;
}
ull bitptr = 0;
unsigned char *memb = (unsigned char *)mem;
longcnt *= 8;
for (ll i = longcnt; i>0; ) {
int bitsneeded = UNPACKBITS;
int k = 0;
while (1) {
if (havebits < bitsneeded) {
accum = getull_swap_unaligned(block + (bitptr >> 3)) &
((0xffffffffffffffffULL) >> (bitptr & 7));
havebits = 64 - (bitptr & 7);
}
auto dc = &(dtabs[k][accum >> (havebits - bitsneeded)]);
if (dc->bytewidth > 0) {
bitptr += dc->bitwidth;
havebits -= dc->bitwidth;
accum &= ((1ULL << havebits) - 1);
if (i >= 8) {
setull_unaligned(memb, dc->d);
memb += dc->bytewidth;
} else {
auto t = dc->d;
for (int ii=0; ii<dc->bytewidth; ii++) {
*memb++ = t;
t >>= 8;
}
}
bitsneeded += 8;
k++;
if (k >= 7)
error("! failure while decoding");
i -= dc->bytewidth;
break;
}
bitsneeded += UNPACKBITS;
if (bitsneeded > 56)
bitsneeded = 56;
k++;
}
setval:
mem[i] = v;
}
if (bytecnt != (bitptr + 7) >> 3)
error("! error when unpacking bytes");
}
void prunetable::writeblock(ull *mem, ull longcnt) {
ull bytecnt = calcblocksize(mem, longcnt);
Expand Down Expand Up @@ -764,7 +797,7 @@ int prunetable::readpt(const puzdef &pd) {
}
ull temp = 0;
r.read((char *)&temp, sizeof(temp));
// error("! I/O error in reading pruning table") ;
// error("! I/O error in reading pruning table");
if (temp != size) {
cout << "Pruning table size is different; recreating pruning table" << endl;
r.close();
Expand Down Expand Up @@ -814,43 +847,79 @@ int prunetable::readpt(const puzdef &pd) {
}
at = 0; // restore the widthbases
int theight[8];
for (int i = 0; i < 8; i++)
theight[i] = 0;
for (int i = 63; i > 0; i--) {
if (widthcounts[i]) {
widthbases[i] = at >> (maxwidth - i);
at += ((ull)widthcounts[i]) << (maxwidth - i);
}
if ((i & 7) == 1) {
int t = maxwidth - i - 7;
if ((i % UNPACKBITS) == 1) {
int t = maxwidth - i - UNPACKBITS + 1;
if (t < 0) {
theight[i >> 3] = (at << -t);
theight[i / UNPACKBITS] = (at << -t);
} else {
theight[i >> 3] = (at + (1LL << t) - 1) >> t;
theight[i / UNPACKBITS] = (at + (1LL << t) - 1) >> t;
}
}
}
for (int i = 0; i < 7; i++)
if (theight[i]) {
tabs[i] = (short *)malloc(theight[i] * sizeof(short));
memset(tabs[i], -1, theight[i] * sizeof(short));
}
for (int i = 0; i < 8; i++)
if (theight[i])
dtabs[i] = (struct decompinfo *)calloc(theight[i], sizeof(struct decompinfo));
at = 0;
int twidth = (maxwidth + 7) & -8;
int twidth = (maxwidth + UNPACKBITS - 1) / UNPACKBITS * UNPACKBITS;
for (int i = 63; i > 0; i--) {
if (widthcounts[i]) {
for (int cp = 0; cp < 272; cp++)
if (codewidths[cp] == i) {
int k = (i - 1) >> 3;
int incsh = twidth - 8 * k - 8;
int k = (i - 1) / UNPACKBITS;
int incsh = twidth - UNPACKBITS * (k + 1);
ull inc = 1LL << incsh;
ull nextat = at + (1LL << (twidth - i));
while (at < nextat) {
tabs[k][at >> incsh] = cp;
if (cp >= 256) {
dtabs[k][at >> incsh] = {(unsigned int)(cp - 256), (uchar)i, 8};
} else {
dtabs[k][at >> incsh] = {(unsigned int)cp, (uchar)i, 1};
}
at += inc;
}
at = nextat;
}
}
}
// now expand the arrays we created so we can unpack multiple bytes at once.
// the challenge here is we need the unmodified table as we modify it, but we don't
// want to allocate whole new copies. we also want to be careful to limit the
// byte count to 4.
// <><>
decompinfo *expander = (decompinfo *)malloc(theight[0] * sizeof(struct decompinfo));
memcpy(expander, dtabs[0], theight[0] * sizeof(struct decompinfo));
for (int k=0; k<8; k++) {
// don't consider expanding anything that would push us past 56 needed bits
if (UNPACKBITS * (k + 1) > 56)
break;
if (theight[k])
for (int i=0; i<theight[k]; i++) {
auto dc = &(dtabs[k][i]);
if (dc->bitwidth && dc->bytewidth < 4) {
int xtra = (k + 1) * UNPACKBITS - dc->bitwidth;
int added = 0;
while (xtra > 0) {
int leftover = i & ((1 << xtra) - 1);
auto dc2 = &(expander[leftover << (UNPACKBITS - xtra)]);
if (dc2->bitwidth == 0 || dc2->bitwidth > xtra || dc->bytewidth + dc2->bytewidth > 4)
break;
xtra -= dc2->bitwidth;
added++;
dc->bytewidth += dc2->bytewidth;
dc->d += dc2->d << (8 * added);
dc->bitwidth += dc2->bitwidth;
}
}
}
}
free(expander);
ll longcnt = (size + 31) >> 5;
if (longcnt % BLOCKSIZE != 0)
error("! when reading, expected multiple of BLOCKSIZE");
Expand Down
14 changes: 9 additions & 5 deletions src/cpp/prunetable.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -76,12 +76,16 @@ struct ioqueue {
ostream *outf;
};
extern struct ioqueue ioqueue;
struct decompinfo {
unsigned int d;
uchar bitwidth, bytewidth;
};
struct prunetable {
prunetable() {
amem = 0;
mem = 0;
for (int i = 0; i < 7; i++)
tabs[i] = 0;
dtabs[i] = 0;
}
prunetable(const puzdef &pd, ull maxmem);
prunetable(const prunetable &) = delete;
Expand Down Expand Up @@ -131,9 +135,9 @@ struct prunetable {
mem = 0;
}
for (int i = 0; i < 7; i++)
if (tabs[i]) {
free(tabs[i]);
tabs[i] = 0;
if (dtabs[i]) {
free(dtabs[i]);
dtabs[i] = 0;
}
}
// if someone set options that affect the hash, we add a suffix to the
Expand All @@ -159,7 +163,7 @@ struct prunetable {
int wval, wbval;
uchar codewidths[544];
ull codevals[544];
short *tabs[7];
decompinfo *dtabs[7];
char justread;
};
#define PRUNETABLE_H
Expand Down

0 comments on commit 1817310

Please sign in to comment.