RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-29 06:10:48 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

BBVectorize: Account for internal shuffle costs

Browse Source 
When target costs are available, use them to account for the costs of
shuffles on internal edges of the DAG of candidate pairs.

Because the shuffle costs here are currently for only the internal edges,
the current target cost model is trivial, and the chain depth requirement
is still in place, I don't yet have an easy test
case. Nevertheless, by looking at the debug output, it does seem to do the right
think to the effective "size" of each DAG of candidate pairs.

llvm-svn: 167217
This commit is contained in:
Hal Finkel 2012-11-01 06:26:34 +00:00
parent 677865ac64
commit 5463245540
1 changed files with 60 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

62
lib/Transforms/Vectorize/BBVectorize.cpp
View File

@ -246,7 +246,10 @@ namespace {
void choosePairs(std::multimap<Value *, Value *> &CandidatePairs,
DenseMap<ValuePair, int> &CandidatePairCostSavings,
std::vector<Value *> &PairableInsts,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
std::multimap<ValuePair, ValuePair> &ConnectedPairs,
std::multimap<ValuePair, ValuePair> &ConnectedPairDeps,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<Value *, Value *>& ChosenPairs);
@ -308,7 +311,10 @@ namespace {
std::multimap<Value *, Value *> &CandidatePairs,
DenseMap<ValuePair, int> &CandidatePairCostSavings,
std::vector<Value *> &PairableInsts,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
std::multimap<ValuePair, ValuePair> &ConnectedPairs,
std::multimap<ValuePair, ValuePair> &ConnectedPairDeps,
DenseSet<ValuePair> &PairableInstUsers,
std::multimap<ValuePair, ValuePair> &PairableInstUserMap,
DenseMap<Value *, Value *> &ChosenPairs,
@ -550,6 +556,7 @@ namespace {
case Instruction::Trunc:
case Instruction::FPTrunc:
case Instruction::BitCast:
case Instruction::ShuffleVector:
return VTTI->getCastInstrCost(Opcode, T1, T2);
}
@ -714,7 +721,8 @@ namespace {
DenseMap<Value *, Value *> ChosenPairs;
choosePairs(CandidatePairs, CandidatePairCostSavings,
PairableInsts, ConnectedPairs,
PairableInsts, FixedOrderPairs, PairConnectionTypes,
ConnectedPairs, ConnectedPairDeps,
PairableInstUsers, ChosenPairs);
if (ChosenPairs.empty()) continue;
@ -1597,7 +1605,10 @@ namespace {
std::multimap<Value *, Value *> &CandidatePairs,
DenseMap<ValuePair, int> &CandidatePairCostSavings,
std::vector<Value *> &PairableInsts,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
std::multimap<ValuePair, ValuePair> &ConnectedPairs,
std::multimap<ValuePair, ValuePair> &ConnectedPairDeps,
DenseSet<ValuePair> &PairableInstUsers,
std::multimap<ValuePair, ValuePair> &PairableInstUserMap,
DenseMap<Value *, Value *> &ChosenPairs,
@ -1654,10 +1665,53 @@ namespace {
int EffSize = 0;
if (VTTI) {
// The node weights represent the cost savings associated with
// fusing the pair of instructions.
for (DenseSet<ValuePair>::iterator S = PrunedTree.begin(),
E = PrunedTree.end(); S != E; ++S) {
if (getDepthFactor(S->first))
EffSize += CandidatePairCostSavings.find(*S)->second;
// The edge weights contribute in a negative sense: they represent
// the cost of shuffles.
VPPIteratorPair IP = ConnectedPairDeps.equal_range(*S);
if (IP.first != ConnectedPairDeps.end()) {
unsigned NumDepsDirect = 0, NumDepsSwap = 0;
for (std::multimap<ValuePair, ValuePair>::iterator Q = IP.first;
Q != IP.second; ++Q) {
DenseMap<VPPair, unsigned>::iterator R =
PairConnectionTypes.find(VPPair(Q->second, Q->first));
assert(R != PairConnectionTypes.end() &&
"Cannot find pair connection type");
if (R->second == PairConnectionDirect)
++NumDepsDirect;
else if (R->second == PairConnectionSwap)
++NumDepsSwap;
}
// If there are more swaps than direct connections, then
// the pair order will be flipped during fusion. So the real
// number of swaps is the minimum number.
bool FlipOrder = !FixedOrderPairs.count(*S) &&
((NumDepsSwap > NumDepsDirect) ||
FixedOrderPairs.count(ValuePair(S->second, S->first)));
for (std::multimap<ValuePair, ValuePair>::iterator Q = IP.first;
Q != IP.second; ++Q) {
DenseMap<VPPair, unsigned>::iterator R =
PairConnectionTypes.find(VPPair(Q->second, Q->first));
assert(R != PairConnectionTypes.end() &&
"Cannot find pair connection type");
Type *Ty1 = Q->second.first->getType(),
*Ty2 = Q->second.second->getType();
Type *VTy = getVecTypeForPair(Ty1, Ty2);
if ((R->second == PairConnectionDirect && FlipOrder) ||
(R->second == PairConnectionSwap && !FlipOrder) ||
R->second == PairConnectionSplat)
EffSize -= (int) getInstrCost(Instruction::ShuffleVector,
VTy, VTy);
}
}
}
} else {
for (DenseSet<ValuePair>::iterator S = PrunedTree.begin(),
@ -1685,7 +1739,10 @@ namespace {
std::multimap<Value *, Value *> &CandidatePairs,
DenseMap<ValuePair, int> &CandidatePairCostSavings,
std::vector<Value *> &PairableInsts,
DenseSet<ValuePair> &FixedOrderPairs,
DenseMap<VPPair, unsigned> &PairConnectionTypes,
std::multimap<ValuePair, ValuePair> &ConnectedPairs,
std::multimap<ValuePair, ValuePair> &ConnectedPairDeps,
DenseSet<ValuePair> &PairableInstUsers,
DenseMap<Value *, Value *>& ChosenPairs) {
bool UseCycleCheck =
@ -1704,7 +1761,8 @@ namespace {
int BestEffSize = 0;
DenseSet<ValuePair> BestTree;
findBestTreeFor(CandidatePairs, CandidatePairCostSavings,
PairableInsts, ConnectedPairs,
PairableInsts, FixedOrderPairs, PairConnectionTypes,
ConnectedPairs, ConnectedPairDeps,
PairableInstUsers, PairableInstUserMap, ChosenPairs,
BestTree, BestMaxDepth, BestEffSize, ChoiceRange,
UseCycleCheck);