// Construct a Derivation that neighbours an existing Derivation.
KBestExtractor::Derivation::Derivation(const Derivation &d, std::size_t i)
{
edge = d.edge;
backPointers = d.backPointers;
subderivations = d.subderivations;
std::size_t j = ++backPointers[i];
scoreBreakdown = d.scoreBreakdown;
// Deduct the score of the old subderivation.
scoreBreakdown.MinusEquals(subderivations[i]->scoreBreakdown);
// Update the subderivation pointer.
boost::shared_ptr<Derivation> newSub(edge->tail[i]->kBestList[j]);
subderivations[i] = newSub;
// Add the score of the new subderivation.
scoreBreakdown.PlusEquals(subderivations[i]->scoreBreakdown);
score = scoreBreakdown.GetWeightedScore();
}
void Enqueue::visit(StmtSingle& s)
{
if (_failure) return;
if (_printer) _printer->visit(s);
// LHS variable must be a memory buffer. It must be writable. The only
// way it could be an image is if it were also an argument to matmul().
// Then it would also appear on the RHS. So it must also be readable.
// As it must be readable and writable, it can not be an image. This
// implies the vector length can never be zero.
_lhsVecLength = getVecLength(s.lhsVariable());
_lhsPrec = s.lhsVariable()->prec();
// RHS variable vector lengths
_smallVecLength = _largeVecLength = _lhsVecLength;
for (set< AstVariable* >::const_iterator
it = s.rhsVariable().begin(); it != s.rhsVariable().end(); it++)
{
size_t vecLen = getVecLength(*it);
if (0 == vecLen)
{
vecLen = PrecType::vecLength( _xid->getPrec(*it) );
}
if (vecLen < _smallVecLength) _smallVecLength = vecLen;
if (vecLen > _largeVecLength) _largeVecLength = vecLen;
}
// stream dimensions come from the left hand side
const size_t lhsWidth = s.lhsVariable()->W();
const size_t lhsHeight = s.lhsVariable()->H();
// if context is the global index space, then every statement with a
// stream larger than one element needs a loop
const bool everyStmtNeedsLoop
= _subs.top()->isGlobalIndexTiles() &&
lhsWidth * lhsHeight > _smallVecLength;
const size_t padW
= (0 != (lhsWidth % _smallVecLength))
? _smallVecLength * (1 + (lhsWidth / _smallVecLength))
: lhsWidth;
// if context does not match the statement stream dimensions
const bool streamSizeMismatch
= _subs.top()->boundingWidth() != padW / _smallVecLength ||
_subs.top()->boundingHeight() != lhsHeight;
// check if a loop is necessary over the stream in the statement
const bool needLoop = everyStmtNeedsLoop || streamSizeMismatch;
// is a loop 1D or 2D?
const bool useLoopH = 1 != lhsHeight;
// new subscript for loop
ForLoopSubscript newSub( padW / _smallVecLength,
lhsHeight);
// begin loop
if (needLoop)
{
// for-loop index for height
const size_t loopIdxH = useLoopH
? _func->loopBegin( 0, lhsHeight )
: -1;
// for-loop index for width
const size_t loopIdxW
= _func->loopBegin( 0, lhsWidth < _smallVecLength
? 1
: padW / _smallVecLength );
// for-loop subscript
newSub.setLoopVars(loopIdxW, loopIdxH);
newSub.setGlobalIndexTiles();
_subs.push(&newSub);
}
// mixed variable vector lengths require multiple statements and components
set< size_t > componentIdxSet;
if (_smallVecLength == _largeVecLength)
{
// all vector lengths are the same, nothing special required
componentIdxSet.insert(-1);
}
else
{
// mixed variable vector lengths in statement
_subs.top()->setMixedVecLength(_smallVecLength);
switch (_smallVecLength)
{
case (1) :
if (2 == _largeVecLength)
{
componentIdxSet.insert(0); // .s0 for vector length 2
componentIdxSet.insert(1); // .s1 for vector length 2
}
else
{
componentIdxSet.insert(0); // .s0 for vector length 2, 4
componentIdxSet.insert(1); // .s1 for vector length 2, 4
componentIdxSet.insert(2); // .s2 for vector length 4
componentIdxSet.insert(3); // .s3 for vector length 4
}
break;
case (2) :
componentIdxSet.insert(0); // .lo for vector length 4
componentIdxSet.insert(1); // .hi for vector length 4
break;
// can not be 4 as must be strictly less than large vector length
}
}
// loop over components
for (set< size_t >::const_iterator
it = componentIdxSet.begin(); it != componentIdxSet.end(); it++)
{
// set variable component
if (-1 != *it) _subs.top()->setMixedComponentIdx(*it);
// clear RHS statement string
_rhsStmt.str(string());
_scalarToScalar = s.scalarToScalar();
// descend into RHS
s.lhsVariable()->getArg(0)->accept(*this); // 0th arg is the RHS
_scalarToScalar = false;
// get LHS variable
Variable* lhsVar = NULL;
if (s.lhsVariable()->isTraceVariable())
{
const uint32_t varNum = s.lhsVariable()->variable();
if (_xid->traceUseRegister().count(varNum))
{
lhsVar = _func->traceVarPrivate(varNum);
}
else
{
lhsVar = _func->traceVar(varNum);
}
}
else
{
const AstVariable* varPtr = s.lhsVariable();
lhsVar = _func->splitVar(varPtr);
}
if (_func->isPrivate(lhsVar))
{
// add new assignment statement
_func->assignStatement(lhsVar, NULL, _rhsStmt.str());
}
else
{
// LHS variable dimensions in subscript for index arithmetic
_subs.top()->setVariable( lhsWidth,
lhsHeight,
_lhsVecLength );
// add new assignment statement
_func->assignStatement(lhsVar, _subs.top(), _rhsStmt.str());
}
}
_subs.top()->unsetMixedVecLength();
// end loop
if (needLoop)
{
if (useLoopH) _func->loopEnd();
_func->loopEnd();
_subs.pop();
}
}
void Enqueue::visit(StmtIndex& s)
{
if (_failure) return;
if (_printer) _printer->visit(s);
// LHS variable must be a memory buffer. It must be writable. The only
// way it could be an image is if it were also an argument to matmul().
// Then it would also appear on the RHS. So it must also be readable.
// As it must be readable and writable, it can not be an image. This
// implies the vector length can never be zero.
_lhsVecLength = getVecLength(s.lhsVariable());
_lhsPrec = s.lhsVariable()->prec();
// stream dimensions come from the left hand side
const size_t lhsWidth = s.lhsVariable()->W();
const size_t lhsHeight = s.lhsVariable()->H();
// if context is the global index space, then every statement with a
// stream larger than one element needs a loop
const bool everyStmtNeedsLoop
= lhsWidth * lhsHeight > _lhsVecLength;
// check if a loop is necessary over the stream in the statement
const bool needLoop = everyStmtNeedsLoop;
// new subscript for loop
ForLoopSubscript newSub( lhsWidth / _lhsVecLength,
lhsHeight );
// is a loop 1D or 2D?
const bool useLoopH = 1 != lhsHeight;
// begin loop
if (needLoop)
{
// for-loop index for height
const size_t loopIdxH = useLoopH
? _func->loopBegin(
0,
lhsHeight )
: -1;
// for-loop index for width
const size_t loopIdxW = _func->loopBegin(
0,
lhsWidth < _lhsVecLength
? 1
: lhsWidth / _lhsVecLength );
// for-loop subscript
newSub.setLoopVars(loopIdxW, loopIdxH);
newSub.setGlobalIndexTiles();
_subs.push(&newSub);
}
// LHS variable dimensions in subscript for index arithmetic
_subs.top()->setVariable( lhsWidth,
lhsHeight,
_lhsVecLength );
// descend into the AST index object
s.idxdataPtr()->accept(*this);
// get LHS variable (kernel generation variable, not the AST variable)
Variable* lhsVar = NULL;
if (s.lhsVariable()->isTraceVariable())
{
const uint32_t varNum = s.lhsVariable()->variable();
if (_xid->traceUseRegister().count(varNum))
{
lhsVar = _func->traceVarPrivate(varNum);
}
else
{
lhsVar = _func->traceVar(varNum);
}
}
else
{
const AstVariable* varPtr = s.lhsVariable();
lhsVar = _func->splitVar(varPtr);
}
// assign LHS with index value
_func->assignStatement(lhsVar, _subs.top(), _rhsStmt.str());
// end loop
if (needLoop)
{
if (useLoopH) _func->loopEnd();
_func->loopEnd();
_subs.pop();
}
}
