void bitbaseInit(void) {
// Allocate memory.
bitbase=malloc((FileNB/2)*RankNB*SqNB*ColourNB*sizeof(uint64_t));
if (bitbase==NULL)
mainFatalError("Error: Could not allocate memory for KPvK bitbase.\n");
// Generate bitbase.
bitbaseGen();
}
void ttInit(void) {
// Setup tt as a HTable.
tt=htableNew(sizeof(TTCluster), ttDefaultSizeMb);
if (tt==NULL)
mainFatalError("Error: Could not allocate transposition table.\n");
// Add uci options to change size and clear.
uciOptionNewSpin("Hash", &htableResizeInterface, tt, 1, ttMaxSizeMb, ttDefaultSizeMb);
uciOptionNewButton("Clear Hash", &htableClearInterface, tt);
}
void bitbaseGen(void) {
// Allocate array to use while generating bitbase.
BitBaseResultFull *array=malloc((FileNB/2)*RankNB*SqNB*ColourNB*SqNB*sizeof(BitBaseResultFull));
if (array==NULL)
mainFatalError("Error: Could not allocate memory for generating KPvK bitbase.\n");
// Mark positions which are obviously won/drawn/invalid (otherwise mark as unknown).
Sq wKingSq, bKingSq;
Colour stm;
File pawnFile;
Rank pawnRank;
for(pawnFile=FileA;pawnFile<=FileD;++pawnFile)
for(pawnRank=Rank8;pawnRank>=Rank2;--pawnRank) {
Sq pawnSq=sqMake(pawnFile, pawnRank);
for(wKingSq=0;wKingSq<SqNB;++wKingSq)
for(stm=0;stm<ColourNB;++stm)
for(bKingSq=0;bKingSq<SqNB;++bKingSq) {
unsigned int index=bitbaseIndexFull(pawnFile, pawnRank, wKingSq, stm, bKingSq);
array[index]=bitbaseComputeStaticResult(pawnSq, wKingSq, stm, bKingSq);
}
}
// Loop over each pawn file and ranks in backwards order (from 7 to 2).
// We can do this as different files are independent and, for example, rank 5
// positions do not depend on any rank 4 positions.
for(pawnFile=FileA;pawnFile<=FileD;++pawnFile)
for(pawnRank=Rank7;pawnRank>=Rank2;--pawnRank) {
Sq pawnSq=sqMake(pawnFile, pawnRank);
// Compute position results based on child positions.
bool change;
do {
change=false;
for(wKingSq=0;wKingSq<SqNB;++wKingSq)
for(stm=0;stm<ColourNB;++stm)
for(bKingSq=0;bKingSq<SqNB;++bKingSq) {
// Position already solved?
unsigned int index=bitbaseIndexFull(pawnFile, pawnRank, wKingSq, stm, bKingSq);
if (array[index]!=BitBaseResultFullUnknown)
continue;
// Try to compute result and update change flag if successful.
BitBaseResultFull result=bitbaseComputeDynamicResult(array, pawnSq, wKingSq, stm, bKingSq);
change|=((array[index]=result)!=BitBaseResultFullUnknown);
}
} while(change);
// Update global array.
// Any positions left 'unknown' are draws (although neither side can 'force' it per se).
for(wKingSq=0;wKingSq<SqNB;++wKingSq)
for(stm=0;stm<ColourNB;++stm) {
unsigned int index=bitbaseIndex(pawnFile, pawnRank, wKingSq, stm);
bitbase[index]=0;
for(bKingSq=0;bKingSq<SqNB;++bKingSq) {
unsigned int fullIndex=bitbaseIndexFull(pawnFile, pawnRank, wKingSq, stm, bKingSq);
STATICASSERT(BitBaseResultWin==1);
if (array[fullIndex]==BitBaseResultFullWin)
bitbase[index]|=(1llu<<bKingSq);
}
}
}
// Verify counts.
# ifndef NDEBUG
unsigned countTotal=0, countWin=0, countDraw=0, countInvalid=0, countUnknown=0;
for(pawnFile=FileA;pawnFile<=FileD;++pawnFile)
for(pawnRank=Rank2;pawnRank<=Rank7;++pawnRank)
for(wKingSq=0;wKingSq<SqNB;++wKingSq)
for(stm=0;stm<ColourNB;++stm)
for(bKingSq=0;bKingSq<SqNB;++bKingSq) {
unsigned int fullIndex=bitbaseIndexFull(pawnFile, pawnRank, wKingSq, stm, bKingSq);
switch(array[fullIndex]) {
case BitBaseResultFullWin:
++countWin;
break;
case BitBaseResultFullDraw:
++countDraw;
break;
case BitBaseResultFullInvalid:
++countInvalid;
break;
case BitBaseResultFullUnknown:
++countUnknown;
break;
}
++countTotal;
}
assert(countTotal==196608);
assert(countWin==111282);
assert(countInvalid==30932);
assert(countDraw+countUnknown==54394);
# endif
// Free working array.
free(array);
}
