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[MemProf] Fix reporting with -memprof-matching-cold-threshold #173327

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[MemProf] Fix reporting with -memprof-matching-cold-threshold #173327

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15 changes: 9 additions & 6 deletions llvm/include/llvm/Analysis/MemoryProfileInfo.h
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Original file line number Diff line number Diff line change
Expand Up @@ -75,8 +75,9 @@ class CallStackTrie {
// If the user has requested reporting of hinted sizes, keep track of the
// associated full stack id and profiled sizes. Can have more than one
// after trimming (e.g. when building from metadata). This is only placed on
// the last (root-most) trie node for each allocation context.
std::vector<ContextTotalSize> ContextSizeInfo;
// the last (root-most) trie node for each allocation context. Also
// track the original allocation type of the context.
std::vector<std::pair<ContextTotalSize, AllocationType>> ContextInfo;
// Map of caller stack id to the corresponding child Trie node.
std::map<uint64_t, CallStackTrieNode *> Callers;
CallStackTrieNode(AllocationType Type)
Expand Down Expand Up @@ -118,10 +119,12 @@ class CallStackTrie {
delete Node;
}

// Recursively build up a complete list of context size information from the
// trie nodes reached form the given Node, for hint size reporting.
void collectContextSizeInfo(CallStackTrieNode *Node,
std::vector<ContextTotalSize> &ContextSizeInfo);
// Recursively build up a complete list of context information from the
// trie nodes reached form the given Node, including each context's
// ContextTotalSize and AllocationType, for hint size reporting.
void collectContextInfo(
CallStackTrieNode *Node,
std::vector<std::pair<ContextTotalSize, AllocationType>> &ContextInfo);

// Recursively convert hot allocation types to notcold, since we don't
// actually do any cloning for hot contexts, to facilitate more aggressive
Expand Down
74 changes: 49 additions & 25 deletions llvm/lib/Analysis/MemoryProfileInfo.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -181,7 +181,13 @@ void CallStackTrie::addCallStack(
Curr = New;
}
assert(Curr);
llvm::append_range(Curr->ContextSizeInfo, ContextSizeInfo);
// Append all of the ContextSizeInfo, along with their original AllocType.
llvm::append_range(
Curr->ContextInfo,
llvm::map_range(
ContextSizeInfo, [AllocType](const ContextTotalSize &CTS) {
return std::pair<ContextTotalSize, AllocationType>(CTS, AllocType);
}));
}

void CallStackTrie::addCallStack(MDNode *MIB) {
Expand Down Expand Up @@ -214,18 +220,18 @@ void CallStackTrie::addCallStack(MDNode *MIB) {
addCallStack(getMIBAllocType(MIB), CallStack, std::move(ContextSizeInfo));
}

static MDNode *createMIBNode(LLVMContext &Ctx, ArrayRef<uint64_t> MIBCallStack,
AllocationType AllocType,
ArrayRef<ContextTotalSize> ContextSizeInfo,
const uint64_t MaxColdSize,
bool BuiltFromExistingMetadata,
uint64_t &TotalBytes, uint64_t &ColdBytes) {
static MDNode *
createMIBNode(LLVMContext &Ctx, ArrayRef<uint64_t> MIBCallStack,
AllocationType AllocType,
ArrayRef<std::pair<ContextTotalSize, AllocationType>> ContextInfo,
const uint64_t MaxColdSize, bool BuiltFromExistingMetadata,
uint64_t &TotalBytes, uint64_t &ColdBytes) {
SmallVector<Metadata *> MIBPayload(
{buildCallstackMetadata(MIBCallStack, Ctx)});
MIBPayload.push_back(
MDString::get(Ctx, getAllocTypeAttributeString(AllocType)));

if (ContextSizeInfo.empty()) {
if (ContextInfo.empty()) {
// The profile matcher should have provided context size info if there was a
// MinCallsiteColdBytePercent < 100. Here we check >=100 to gracefully
// handle a user-provided percent larger than 100. However, we may not have
Expand All @@ -234,7 +240,8 @@ static MDNode *createMIBNode(LLVMContext &Ctx, ArrayRef<uint64_t> MIBCallStack,
return MDNode::get(Ctx, MIBPayload);
}

for (const auto &[FullStackId, TotalSize] : ContextSizeInfo) {
for (const auto &[CSI, AT] : ContextInfo) {
const auto &[FullStackId, TotalSize] = CSI;
TotalBytes += TotalSize;
bool LargeColdContext = false;
if (AllocType == AllocationType::Cold) {
Expand Down Expand Up @@ -267,11 +274,12 @@ static MDNode *createMIBNode(LLVMContext &Ctx, ArrayRef<uint64_t> MIBCallStack,
return MDNode::get(Ctx, MIBPayload);
}

void CallStackTrie::collectContextSizeInfo(
CallStackTrieNode *Node, std::vector<ContextTotalSize> &ContextSizeInfo) {
llvm::append_range(ContextSizeInfo, Node->ContextSizeInfo);
void CallStackTrie::collectContextInfo(
CallStackTrieNode *Node,
std::vector<std::pair<ContextTotalSize, AllocationType>> &ContextInfo) {
llvm::append_range(ContextInfo, Node->ContextInfo);
for (auto &Caller : Node->Callers)
collectContextSizeInfo(Caller.second, ContextSizeInfo);
collectContextInfo(Caller.second, ContextInfo);
}

void CallStackTrie::convertHotToNotCold(CallStackTrieNode *Node) {
Expand All @@ -283,6 +291,17 @@ void CallStackTrie::convertHotToNotCold(CallStackTrieNode *Node) {
convertHotToNotCold(Caller.second);
}

// Helper to emit messages for non-cold contexts that are ignored for various
// reasons when reporting of hinted bytes is enabled.
static void emitIgnoredNonColdContextMessage(StringRef Tag,
uint64_t FullStackId,
StringRef Extra,
uint64_t TotalSize) {
errs() << "MemProf hinting: Total size for " << Tag
<< " non-cold full allocation context hash " << FullStackId << Extra
<< ": " << TotalSize << "\n";
}

// Copy over some or all of NewMIBNodes to the SavedMIBNodes vector, depending
// on options that enable filtering out some NotCold contexts.
static void saveFilteredNewMIBNodes(std::vector<Metadata *> &NewMIBNodes,
Expand Down Expand Up @@ -321,9 +340,7 @@ static void saveFilteredNewMIBNodes(std::vector<Metadata *> &NewMIBNodes,
uint64_t TS =
mdconst::dyn_extract<ConstantInt>(ContextSizePair->getOperand(1))
->getZExtValue();
errs() << "MemProf hinting: Total size for " << Tag
<< " non-cold full allocation context hash " << FullStackId
<< Extra << ": " << TS << "\n";
emitIgnoredNonColdContextMessage(Tag, FullStackId, Extra, TS);
}
};

Expand Down Expand Up @@ -430,10 +447,10 @@ bool CallStackTrie::buildMIBNodes(CallStackTrieNode *Node, LLVMContext &Ctx,
// Trim context below the first node in a prefix with a single alloc type.
// Add an MIB record for the current call stack prefix.
if (hasSingleAllocType(Node->AllocTypes)) {
std::vector<ContextTotalSize> ContextSizeInfo;
collectContextSizeInfo(Node, ContextSizeInfo);
std::vector<std::pair<ContextTotalSize, AllocationType>> ContextInfo;
collectContextInfo(Node, ContextInfo);
MIBNodes.push_back(createMIBNode(
Ctx, MIBCallStack, (AllocationType)Node->AllocTypes, ContextSizeInfo,
Ctx, MIBCallStack, (AllocationType)Node->AllocTypes, ContextInfo,
MaxColdSize, BuiltFromExistingMetadata, TotalBytes, ColdBytes));
return true;
}
Expand Down Expand Up @@ -486,10 +503,10 @@ bool CallStackTrie::buildMIBNodes(CallStackTrieNode *Node, LLVMContext &Ctx,
// non-cold allocation type.
if (!CalleeHasAmbiguousCallerContext)
return false;
std::vector<ContextTotalSize> ContextSizeInfo;
collectContextSizeInfo(Node, ContextSizeInfo);
std::vector<std::pair<ContextTotalSize, AllocationType>> ContextInfo;
collectContextInfo(Node, ContextInfo);
MIBNodes.push_back(createMIBNode(
Ctx, MIBCallStack, AllocationType::NotCold, ContextSizeInfo, MaxColdSize,
Ctx, MIBCallStack, AllocationType::NotCold, ContextInfo, MaxColdSize,
BuiltFromExistingMetadata, TotalBytes, ColdBytes));
return true;
}
Expand All @@ -503,9 +520,16 @@ void CallStackTrie::addSingleAllocTypeAttribute(CallBase *CI, AllocationType AT,
removeAnyExistingAmbiguousAttribute(CI);
CI->addFnAttr(A);
if (MemProfReportHintedSizes) {
std::vector<ContextTotalSize> ContextSizeInfo;
collectContextSizeInfo(Alloc, ContextSizeInfo);
for (const auto &[FullStackId, TotalSize] : ContextSizeInfo) {
std::vector<std::pair<ContextTotalSize, AllocationType>> ContextInfo;
collectContextInfo(Alloc, ContextInfo);
for (const auto &[CSI, OrigAT] : ContextInfo) {
const auto &[FullStackId, TotalSize] = CSI;
// If the original alloc type is not the one being applied as the hint,
// report that we ignored this context.
if (AT != OrigAT) {
emitIgnoredNonColdContextMessage("ignored", FullStackId, "", TotalSize);
continue;
}
errs() << "MemProf hinting: Total size for full allocation context hash "
<< FullStackId << " and " << Descriptor << " alloc type "
<< getAllocTypeAttributeString(AT) << ": " << TotalSize << "\n";
Expand Down
4 changes: 2 additions & 2 deletions llvm/test/Transforms/PGOProfile/memprof.ll
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Expand Up @@ -400,10 +400,10 @@ for.end: ; preds = %for.cond
;; with the full allocation context hash, type, and size in bytes.
; TOTALSIZESTHRESH60: Total size for full allocation context hash 8525406123785421946 and dominant alloc type cold: 10
; TOTALSIZESTHRESH60: Total size for full allocation context hash 11714230664165068698 and dominant alloc type cold: 10
; TOTALSIZESTHRESH60: Total size for full allocation context hash 5725971306423925017 and dominant alloc type cold: 10
; TOTALSIZESTHRESH60: Total size for ignored non-cold full allocation context hash 5725971306423925017: 10
; TOTALSIZESTHRESH60: Total size for full allocation context hash 16342802530253093571 and dominant alloc type cold: 10
; TOTALSIZESTHRESH60: Total size for full allocation context hash 18254812774972004394 and dominant alloc type cold: 10
; TOTALSIZESTHRESH60: Total size for full allocation context hash 1093248920606587996 and dominant alloc type cold: 10
; TOTALSIZESTHRESH60: Total size for ignored non-cold full allocation context hash 1093248920606587996: 10
; TOTALSIZESSINGLE: Total size for full allocation context hash 6792096022461663180 and single alloc type notcold: 10
; REMARKSINGLE: remark: memprof.cc:25:13: call in function main marked with memprof allocation attribute notcold
; TOTALSIZESSINGLE: Total size for full allocation context hash 15737101490731057601 and single alloc type cold: 10
Expand Down