// Currently the transfer function used by DFAGen is assumed to be:
// Y = gen[n] U (X - kill[n]).
OA_ptr<DataFlowSet>
ManagerReachingDefs::transfer(
OA_ptr<DataFlowSet> xdfset,
StmtHandle stmt)
{
OA_ptr<ReachingDefsDFSet> xdfgenset;
xdfgenset = xdfset.convert<ReachingDefsDFSet>();
OA_ptr<ReachingDefsDFSet> x;
x = new ReachingDefsDFSet(*xdfgenset);
// if debug mode is on print information about transfer function
if (debug) {
cout << "In transfer: " << endl;
cout << "\t Stmt = " << mIR->toString(stmt) << endl;
cout << "\t X = ";
dumpset(x);
}
OA_ptr<DataFlowSet> genBaseObj = genSet(stmt, x);
OA_ptr<ReachingDefsDFSet> gen = genBaseObj.convert<ReachingDefsDFSet>();
OA_ptr<DataFlowSet> killBaseObj = killSet(stmt, x);
OA_ptr<ReachingDefsDFSet> kill = killBaseObj.convert<ReachingDefsDFSet>();
// Add gen[n] to Y
OA_ptr<DataFlow::DataFlowSetImplIterator<StmtHandle > > genIter;
genIter = new DataFlow::DataFlowSetImplIterator<StmtHandle > (gen);
for(; genIter->isValid(); ++(*genIter)) {
StmtHandle genVal;
genVal = genIter->current();
mReachingDefsMap->insert(stmt, genVal);
}
// Add X - kill[n] to Y
x->minusEqu(*kill);
OA_ptr<DataFlow::DataFlowSetImplIterator<StmtHandle > > xIter;
xIter = new DataFlow::DataFlowSetImplIterator<StmtHandle > (x);
for(; xIter->isValid(); ++(*xIter)) {
StmtHandle xVal;
xVal = xIter->current();
mReachingDefsMap->insert(stmt, xVal);
}
// if debug mode is on print information about transfer function
if(debug) {
cout << "\t gen = ";
dumpset(gen);
cout << "\t kill = ";
dumpset(kill);
cout << "\t Y = ";
dumpset(mReachingDefsMap->getReachingDefsSet(stmt));
}
return mReachingDefsMap->getReachingDefsSet(stmt);
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
void AggregateCopyPropagation::LocalCopyPropagation(Block* block,
TOperandToIdDict& availableCopies) {
BitVector killSet(infoList_.Count());
BitVector copySet(infoList_.Count()); // Unused here.
// Try to use the original operand instead of the copy.
// We need to recompute the 'kill' set, because copies available
// at the block entry might be invalidated by 'store' and 'call'.
for(auto instr = block->FirstInstruction(); instr;
instr = instr->NextInstruction()) {
if(auto callInstr = instr->As<CallInstr>()) {
// This might be a call that kills copies.
AddToKillSet(callInstr, killSet, copySet);
ReplaceWithOriginal(callInstr, availableCopies, killSet);
}
else if(auto storeInstr = instr->As<StoreInstr>()) {
AddToKillSet(storeInstr, killSet, copySet);
}
else if(auto loadInstr = instr->As<LoadInstr>()) {
// Try to replace the operands with the original ones.
ReplaceWithOriginal(loadInstr, availableCopies, killSet);
}
}
}
