unsigned
DWARFVerifier::verifyDebugNamesCULists(const DWARFDebugNames &AccelTable) {
// A map from CU offset to the (first) Name Index offset which claims to index
// this CU.
DenseMap<uint32_t, uint32_t> CUMap;
const uint32_t NotIndexed = std::numeric_limits<uint32_t>::max();
CUMap.reserve(DCtx.getNumCompileUnits());
for (const auto &CU : DCtx.compile_units())
CUMap[CU->getOffset()] = NotIndexed;
unsigned NumErrors = 0;
for (const DWARFDebugNames::NameIndex &NI : AccelTable) {
if (NI.getCUCount() == 0) {
error() << formatv("Name Index @ {0:x} does not index any CU\n",
NI.getUnitOffset());
++NumErrors;
continue;
}
for (uint32_t CU = 0, End = NI.getCUCount(); CU < End; ++CU) {
uint32_t Offset = NI.getCUOffset(CU);
auto Iter = CUMap.find(Offset);
if (Iter == CUMap.end()) {
error() << formatv(
"Name Index @ {0:x} references a non-existing CU @ {1:x}\n",
NI.getUnitOffset(), Offset);
++NumErrors;
continue;
}
if (Iter->second != NotIndexed) {
error() << formatv("Name Index @ {0:x} references a CU @ {1:x}, but "
"this CU is already indexed by Name Index @ {2:x}\n",
NI.getUnitOffset(), Offset, Iter->second);
continue;
}
Iter->second = NI.getUnitOffset();
}
}
for (const auto &KV : CUMap) {
if (KV.second == NotIndexed)
warn() << formatv("CU @ {0:x} not covered by any Name Index\n", KV.first);
}
return NumErrors;
}
// Builds the graph + StratifiedSets for a function.
CFLAAResult::FunctionInfo CFLAAResult::buildSetsFrom(Function *Fn) {
NodeMapT Map;
GraphT Graph;
SmallVector<Value *, 4> ReturnedValues;
buildGraphFrom(*this, Fn, ReturnedValues, Map, Graph);
DenseMap<GraphT::Node, Value *> NodeValueMap;
NodeValueMap.reserve(Map.size());
for (const auto &Pair : Map)
NodeValueMap.insert(std::make_pair(Pair.second, Pair.first));
const auto findValueOrDie = [&NodeValueMap](GraphT::Node Node) {
auto ValIter = NodeValueMap.find(Node);
assert(ValIter != NodeValueMap.end());
return ValIter->second;
};
StratifiedSetsBuilder<Value *> Builder;
SmallVector<GraphT::Node, 16> Worklist;
for (auto &Pair : Map) {
Worklist.clear();
auto *Value = Pair.first;
Builder.add(Value);
auto InitialNode = Pair.second;
Worklist.push_back(InitialNode);
while (!Worklist.empty()) {
auto Node = Worklist.pop_back_val();
auto *CurValue = findValueOrDie(Node);
if (canSkipAddingToSets(CurValue))
continue;
Optional<StratifiedAttr> MaybeCurIndex = valueToAttrIndex(CurValue);
if (MaybeCurIndex)
Builder.noteAttributes(CurValue, *MaybeCurIndex);
for (const auto &EdgeTuple : Graph.edgesFor(Node)) {
auto Weight = std::get<0>(EdgeTuple);
auto Label = Weight.first;
auto &OtherNode = std::get<1>(EdgeTuple);
auto *OtherValue = findValueOrDie(OtherNode);
if (canSkipAddingToSets(OtherValue))
continue;
bool Added;
switch (directionOfEdgeType(Label)) {
case Level::Above:
Added = Builder.addAbove(CurValue, OtherValue);
break;
case Level::Below:
Added = Builder.addBelow(CurValue, OtherValue);
break;
case Level::Same:
Added = Builder.addWith(CurValue, OtherValue);
break;
}
auto Aliasing = Weight.second;
if (MaybeCurIndex)
Aliasing.set(*MaybeCurIndex);
if (auto MaybeOtherIndex = valueToAttrIndex(OtherValue))
Aliasing.set(*MaybeOtherIndex);
Builder.noteAttributes(CurValue, Aliasing);
Builder.noteAttributes(OtherValue, Aliasing);
if (Added)
Worklist.push_back(OtherNode);
}
}
}
// There are times when we end up with parameters not in our graph (i.e. if
// it's only used as the condition of a branch). Other bits of code depend on
// things that were present during construction being present in the graph.
// So, we add all present arguments here.
for (auto &Arg : Fn->args()) {
if (!Builder.add(&Arg))
continue;
auto Attrs = valueToAttrIndex(&Arg);
if (Attrs.hasValue())
Builder.noteAttributes(&Arg, *Attrs);
}
return FunctionInfo(Builder.build(), std::move(ReturnedValues));
}
/// Given \p BBs as input, find another set of BBs which collectively
/// dominates \p BBs and have the minimal sum of frequencies. Return the BB
/// set found in \p BBs.
static void findBestInsertionSet(DominatorTree &DT, BlockFrequencyInfo &BFI,
BasicBlock *Entry,
SmallPtrSet<BasicBlock *, 8> &BBs) {
assert(!BBs.count(Entry) && "Assume Entry is not in BBs");
// Nodes on the current path to the root.
SmallPtrSet<BasicBlock *, 8> Path;
// Candidates includes any block 'BB' in set 'BBs' that is not strictly
// dominated by any other blocks in set 'BBs', and all nodes in the path
// in the dominator tree from Entry to 'BB'.
SmallPtrSet<BasicBlock *, 16> Candidates;
for (auto BB : BBs) {
// Ignore unreachable basic blocks.
if (!DT.isReachableFromEntry(BB))
continue;
Path.clear();
// Walk up the dominator tree until Entry or another BB in BBs
// is reached. Insert the nodes on the way to the Path.
BasicBlock *Node = BB;
// The "Path" is a candidate path to be added into Candidates set.
bool isCandidate = false;
do {
Path.insert(Node);
if (Node == Entry || Candidates.count(Node)) {
isCandidate = true;
break;
}
assert(DT.getNode(Node)->getIDom() &&
"Entry doens't dominate current Node");
Node = DT.getNode(Node)->getIDom()->getBlock();
} while (!BBs.count(Node));
// If isCandidate is false, Node is another Block in BBs dominating
// current 'BB'. Drop the nodes on the Path.
if (!isCandidate)
continue;
// Add nodes on the Path into Candidates.
Candidates.insert(Path.begin(), Path.end());
}
// Sort the nodes in Candidates in top-down order and save the nodes
// in Orders.
unsigned Idx = 0;
SmallVector<BasicBlock *, 16> Orders;
Orders.push_back(Entry);
while (Idx != Orders.size()) {
BasicBlock *Node = Orders[Idx++];
for (auto ChildDomNode : DT.getNode(Node)->getChildren()) {
if (Candidates.count(ChildDomNode->getBlock()))
Orders.push_back(ChildDomNode->getBlock());
}
}
// Visit Orders in bottom-up order.
using InsertPtsCostPair =
std::pair<SmallPtrSet<BasicBlock *, 16>, BlockFrequency>;
// InsertPtsMap is a map from a BB to the best insertion points for the
// subtree of BB (subtree not including the BB itself).
DenseMap<BasicBlock *, InsertPtsCostPair> InsertPtsMap;
InsertPtsMap.reserve(Orders.size() + 1);
for (auto RIt = Orders.rbegin(); RIt != Orders.rend(); RIt++) {
BasicBlock *Node = *RIt;
bool NodeInBBs = BBs.count(Node);
SmallPtrSet<BasicBlock *, 16> &InsertPts = InsertPtsMap[Node].first;
BlockFrequency &InsertPtsFreq = InsertPtsMap[Node].second;
// Return the optimal insert points in BBs.
if (Node == Entry) {
BBs.clear();
if (InsertPtsFreq > BFI.getBlockFreq(Node) ||
(InsertPtsFreq == BFI.getBlockFreq(Node) && InsertPts.size() > 1))
BBs.insert(Entry);
else
BBs.insert(InsertPts.begin(), InsertPts.end());
break;
}
BasicBlock *Parent = DT.getNode(Node)->getIDom()->getBlock();
// Initially, ParentInsertPts is empty and ParentPtsFreq is 0. Every child
// will update its parent's ParentInsertPts and ParentPtsFreq.
SmallPtrSet<BasicBlock *, 16> &ParentInsertPts = InsertPtsMap[Parent].first;
BlockFrequency &ParentPtsFreq = InsertPtsMap[Parent].second;
// Choose to insert in Node or in subtree of Node.
// Don't hoist to EHPad because we may not find a proper place to insert
// in EHPad.
// If the total frequency of InsertPts is the same as the frequency of the
// target Node, and InsertPts contains more than one nodes, choose hoisting
// to reduce code size.
if (NodeInBBs ||
(!Node->isEHPad() &&
(InsertPtsFreq > BFI.getBlockFreq(Node) ||
(InsertPtsFreq == BFI.getBlockFreq(Node) && InsertPts.size() > 1)))) {
ParentInsertPts.insert(Node);
ParentPtsFreq += BFI.getBlockFreq(Node);
} else {
ParentInsertPts.insert(InsertPts.begin(), InsertPts.end());
ParentPtsFreq += InsertPtsFreq;
}
}
}
