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merged 2 commits into from
Nov 15, 2023
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[nfc][instr] Encapsulate CFGMST #72207

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[nfc][instr] Encapsulate CFGMST
mtrofin Nov 14, 2023
dd9f5ed
Add a `numEdges`
mtrofin Nov 15, 2023
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64 changes: 36 additions & 28 deletions llvm/include/llvm/Transforms/Instrumentation/CFGMST.h
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Original file line number Diff line number Diff line change
Expand Up @@ -35,7 +35,6 @@ namespace llvm {
/// Implements a Union-find algorithm to compute Minimum Spanning Tree
/// for a given CFG.
template <class Edge, class BBInfo> class CFGMST {
public:
Function &F;

// Store all the edges in CFG. It may contain some stale edges
Expand All @@ -49,6 +48,12 @@ template <class Edge, class BBInfo> class CFGMST {
// (For function with an infinite loop, this block may be absent)
bool ExitBlockFound = false;

BranchProbabilityInfo *const BPI;
BlockFrequencyInfo *const BFI;

// If function entry will be always instrumented.
const bool InstrumentFuncEntry;

// Find the root group of the G and compress the path from G to the root.
BBInfo *findAndCompressGroup(BBInfo *G) {
if (G->Group != G)
Expand Down Expand Up @@ -77,21 +82,6 @@ template <class Edge, class BBInfo> class CFGMST {
return true;
}

// Give BB, return the auxiliary information.
BBInfo &getBBInfo(const BasicBlock *BB) const {
auto It = BBInfos.find(BB);
assert(It->second.get() != nullptr);
return *It->second.get();
}

// Give BB, return the auxiliary information if it's available.
BBInfo *findBBInfo(const BasicBlock *BB) const {
auto It = BBInfos.find(BB);
if (It == BBInfos.end())
return nullptr;
return It->second.get();
}

// Traverse the CFG using a stack. Find all the edges and assign the weight.
// Edges with large weight will be put into MST first so they are less likely
// to be instrumented.
Expand Down Expand Up @@ -236,6 +226,7 @@ template <class Edge, class BBInfo> class CFGMST {
}
}

public:
// Dump the Debug information about the instrumentation.
void dumpEdges(raw_ostream &OS, const Twine &Message) const {
if (!Message.str().empty())
Expand Down Expand Up @@ -274,25 +265,42 @@ template <class Edge, class BBInfo> class CFGMST {
return *AllEdges.back();
}

BranchProbabilityInfo *BPI;
BlockFrequencyInfo *BFI;

// If function entry will be always instrumented.
bool InstrumentFuncEntry;

public:
CFGMST(Function &Func, bool InstrumentFuncEntry_,
BranchProbabilityInfo *BPI_ = nullptr,
BlockFrequencyInfo *BFI_ = nullptr)
: F(Func), BPI(BPI_), BFI(BFI_),
InstrumentFuncEntry(InstrumentFuncEntry_) {
CFGMST(Function &Func, bool InstrumentFuncEntry,
BranchProbabilityInfo *BPI = nullptr,
BlockFrequencyInfo *BFI = nullptr)
: F(Func), BPI(BPI), BFI(BFI), InstrumentFuncEntry(InstrumentFuncEntry) {
buildEdges();
sortEdgesByWeight();
computeMinimumSpanningTree();
if (AllEdges.size() > 1 && InstrumentFuncEntry)
std::iter_swap(std::move(AllEdges.begin()),
std::move(AllEdges.begin() + AllEdges.size() - 1));
}

const std::vector<std::unique_ptr<Edge>> &allEdges() const {
return AllEdges;
}

std::vector<std::unique_ptr<Edge>> &allEdges() { return AllEdges; }

size_t numEdges() const { return AllEdges.size(); }

size_t bbInfoSize() const { return BBInfos.size(); }

// Give BB, return the auxiliary information.
BBInfo &getBBInfo(const BasicBlock *BB) const {
auto It = BBInfos.find(BB);
assert(It->second.get() != nullptr);
return *It->second.get();
}

// Give BB, return the auxiliary information if it's available.
BBInfo *findBBInfo(const BasicBlock *BB) const {
auto It = BBInfos.find(BB);
if (It == BBInfos.end())
return nullptr;
return It->second.get();
}
};

} // end namespace llvm
Expand Down
20 changes: 10 additions & 10 deletions llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp
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Expand Up @@ -750,7 +750,7 @@ static BasicBlock *getInstrBB(CFGMST<Edge, BBInfo> &MST, Edge &E,
#ifndef NDEBUG
static void dumpEdges(CFGMST<Edge, BBInfo> &MST, GCOVFunction &GF) {
size_t ID = 0;
for (auto &E : make_pointee_range(MST.AllEdges)) {
for (const auto &E : make_pointee_range(MST.allEdges())) {
GCOVBlock &Src = E.SrcBB ? GF.getBlock(E.SrcBB) : GF.getEntryBlock();
GCOVBlock &Dst = E.DestBB ? GF.getBlock(E.DestBB) : GF.getReturnBlock();
dbgs() << " Edge " << ID++ << ": " << Src.Number << "->" << Dst.Number
Expand Down Expand Up @@ -820,8 +820,8 @@ bool GCOVProfiler::emitProfileNotes(
CFGMST<Edge, BBInfo> MST(F, /*InstrumentFuncEntry_=*/false, BPI, BFI);

// getInstrBB can split basic blocks and push elements to AllEdges.
for (size_t I : llvm::seq<size_t>(0, MST.AllEdges.size())) {
auto &E = *MST.AllEdges[I];
for (size_t I : llvm::seq<size_t>(0, MST.numEdges())) {
auto &E = *MST.allEdges()[I];
// For now, disable spanning tree optimization when fork or exec* is
// used.
if (HasExecOrFork)
Expand All @@ -836,16 +836,16 @@ bool GCOVProfiler::emitProfileNotes(

// Some non-tree edges are IndirectBr which cannot be split. Ignore them
// as well.
llvm::erase_if(MST.AllEdges, [](std::unique_ptr<Edge> &E) {
llvm::erase_if(MST.allEdges(), [](std::unique_ptr<Edge> &E) {
return E->Removed || (!E->InMST && !E->Place);
});
const size_t Measured =
std::stable_partition(
MST.AllEdges.begin(), MST.AllEdges.end(),
MST.allEdges().begin(), MST.allEdges().end(),
[](std::unique_ptr<Edge> &E) { return E->Place; }) -
MST.AllEdges.begin();
MST.allEdges().begin();
for (size_t I : llvm::seq<size_t>(0, Measured)) {
Edge &E = *MST.AllEdges[I];
Edge &E = *MST.allEdges()[I];
GCOVBlock &Src =
E.SrcBB ? Func.getBlock(E.SrcBB) : Func.getEntryBlock();
GCOVBlock &Dst =
Expand All @@ -854,13 +854,13 @@ bool GCOVProfiler::emitProfileNotes(
E.DstNumber = Dst.Number;
}
std::stable_sort(
MST.AllEdges.begin(), MST.AllEdges.begin() + Measured,
MST.allEdges().begin(), MST.allEdges().begin() + Measured,
[](const std::unique_ptr<Edge> &L, const std::unique_ptr<Edge> &R) {
return L->SrcNumber != R->SrcNumber ? L->SrcNumber < R->SrcNumber
: L->DstNumber < R->DstNumber;
});

for (const Edge &E : make_pointee_range(MST.AllEdges)) {
for (const Edge &E : make_pointee_range(MST.allEdges())) {
GCOVBlock &Src =
E.SrcBB ? Func.getBlock(E.SrcBB) : Func.getEntryBlock();
GCOVBlock &Dst =
Expand Down Expand Up @@ -917,7 +917,7 @@ bool GCOVProfiler::emitProfileNotes(
CountersBySP.emplace_back(Counters, SP);

for (size_t I : llvm::seq<size_t>(0, Measured)) {
const Edge &E = *MST.AllEdges[I];
const Edge &E = *MST.allEdges()[I];
IRBuilder<> Builder(E.Place, E.Place->getFirstInsertionPt());
Value *V = Builder.CreateConstInBoundsGEP2_64(
Counters->getValueType(), Counters, 0, I);
Expand Down
24 changes: 12 additions & 12 deletions llvm/lib/Transforms/Instrumentation/PGOInstrumentation.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -582,12 +582,12 @@ template <class Edge, class BBInfo> class FuncPGOInstrumentation {
if (!IsCS) {
NumOfPGOSelectInsts += SIVisitor.getNumOfSelectInsts();
NumOfPGOMemIntrinsics += ValueSites[IPVK_MemOPSize].size();
NumOfPGOBB += MST.BBInfos.size();
NumOfPGOBB += MST.bbInfoSize();
ValueSites[IPVK_IndirectCallTarget] = VPC.get(IPVK_IndirectCallTarget);
} else {
NumOfCSPGOSelectInsts += SIVisitor.getNumOfSelectInsts();
NumOfCSPGOMemIntrinsics += ValueSites[IPVK_MemOPSize].size();
NumOfCSPGOBB += MST.BBInfos.size();
NumOfCSPGOBB += MST.bbInfoSize();
}

FuncName = getIRPGOFuncName(F);
Expand All @@ -597,7 +597,7 @@ template <class Edge, class BBInfo> class FuncPGOInstrumentation {
renameComdatFunction();
LLVM_DEBUG(dumpInfo("after CFGMST"));

for (auto &E : MST.AllEdges) {
for (const auto &E : MST.allEdges()) {
if (E->Removed)
continue;
IsCS ? NumOfCSPGOEdge++ : NumOfPGOEdge++;
Expand Down Expand Up @@ -640,7 +640,7 @@ void FuncPGOInstrumentation<Edge, BBInfo>::computeCFGHash() {
FunctionHash = (uint64_t)SIVisitor.getNumOfSelectInsts() << 56 |
(uint64_t)ValueSites[IPVK_IndirectCallTarget].size() << 48 |
//(uint64_t)ValueSites[IPVK_MemOPSize].size() << 40 |
(uint64_t)MST.AllEdges.size() << 32 | JC.getCRC();
(uint64_t)MST.numEdges() << 32 | JC.getCRC();
} else {
// The higher 32 bits.
auto updateJCH = [&JCH](uint64_t Num) {
Expand All @@ -654,7 +654,7 @@ void FuncPGOInstrumentation<Edge, BBInfo>::computeCFGHash() {
if (BCI) {
updateJCH(BCI->getInstrumentedBlocksHash());
} else {
updateJCH((uint64_t)MST.AllEdges.size());
updateJCH((uint64_t)MST.numEdges());
}

// Hash format for context sensitive profile. Reserve 4 bits for other
Expand All @@ -669,7 +669,7 @@ void FuncPGOInstrumentation<Edge, BBInfo>::computeCFGHash() {
LLVM_DEBUG(dbgs() << "Function Hash Computation for " << F.getName() << ":\n"
<< " CRC = " << JC.getCRC()
<< ", Selects = " << SIVisitor.getNumOfSelectInsts()
<< ", Edges = " << MST.AllEdges.size() << ", ICSites = "
<< ", Edges = " << MST.numEdges() << ", ICSites = "
<< ValueSites[IPVK_IndirectCallTarget].size());
if (!PGOOldCFGHashing) {
LLVM_DEBUG(dbgs() << ", Memops = " << ValueSites[IPVK_MemOPSize].size()
Expand Down Expand Up @@ -757,8 +757,8 @@ void FuncPGOInstrumentation<Edge, BBInfo>::getInstrumentBBs(

// Use a worklist as we will update the vector during the iteration.
std::vector<Edge *> EdgeList;
EdgeList.reserve(MST.AllEdges.size());
for (auto &E : MST.AllEdges)
EdgeList.reserve(MST.numEdges());
for (const auto &E : MST.allEdges())
EdgeList.push_back(E.get());

for (auto &E : EdgeList) {
Expand Down Expand Up @@ -1165,12 +1165,12 @@ class PGOUseFunc {
} // end anonymous namespace

/// Set up InEdges/OutEdges for all BBs in the MST.
static void
setupBBInfoEdges(FuncPGOInstrumentation<PGOUseEdge, PGOUseBBInfo> &FuncInfo) {
static void setupBBInfoEdges(
const FuncPGOInstrumentation<PGOUseEdge, PGOUseBBInfo> &FuncInfo) {
// This is not required when there is block coverage inference.
if (FuncInfo.BCI)
return;
for (auto &E : FuncInfo.MST.AllEdges) {
for (const auto &E : FuncInfo.MST.allEdges()) {
if (E->Removed)
continue;
const BasicBlock *SrcBB = E->SrcBB;
Expand Down Expand Up @@ -1226,7 +1226,7 @@ bool PGOUseFunc::setInstrumentedCounts(
// Set the profile count the Instrumented edges. There are BBs that not in
// MST but not instrumented. Need to set the edge count value so that we can
// populate the profile counts later.
for (auto &E : FuncInfo.MST.AllEdges) {
for (const auto &E : FuncInfo.MST.allEdges()) {
if (E->Removed || E->InMST)
continue;
const BasicBlock *SrcBB = E->SrcBB;
Expand Down