llvm-6502/lib/IR/Metadata.cpp
Duncan P. N. Exon Smith 85cbe57fc5 IR: Don't track nullptr on metadata RAUW
The RAUW support in `Metadata` supports going to `nullptr` specifically
to handle values being deleted, causing `ValueAsMetadata` to be deleted.

Fix the case where the reference is from a `TrackingMDRef` (as opposed
to an `MDOperand` or a `MetadataAsValue`).

This is surprisingly rare -- metadata tracked by `TrackingMDRef` going
to null -- but it came up in an openSUSE bootstrap during inlining.  The
tracking ref was held by the `ValueMap` because it was referencing a
local, the basic block containing the local became dead after it had
been merged in, and when the local was deleted, the tracking ref
asserted in an `isa`.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224146 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-12 19:24:33 +00:00

1055 lines
32 KiB
C++

//===-- Metadata.cpp - Implement Metadata classes -------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Metadata classes.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/Metadata.h"
#include "LLVMContextImpl.h"
#include "SymbolTableListTraitsImpl.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/LeakDetector.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/ValueHandle.h"
using namespace llvm;
MetadataAsValue::MetadataAsValue(Type *Ty, Metadata *MD)
: Value(Ty, MetadataAsValueVal), MD(MD) {
track();
}
MetadataAsValue::~MetadataAsValue() {
getType()->getContext().pImpl->MetadataAsValues.erase(MD);
untrack();
}
/// \brief Canonicalize metadata arguments to intrinsics.
///
/// To support bitcode upgrades (and assembly semantic sugar) for \a
/// MetadataAsValue, we need to canonicalize certain metadata.
///
/// - nullptr is replaced by an empty MDNode.
/// - An MDNode with a single null operand is replaced by an empty MDNode.
/// - An MDNode whose only operand is a \a ConstantAsMetadata gets skipped.
///
/// This maintains readability of bitcode from when metadata was a type of
/// value, and these bridges were unnecessary.
static Metadata *canonicalizeMetadataForValue(LLVMContext &Context,
Metadata *MD) {
if (!MD)
// !{}
return MDNode::get(Context, None);
// Return early if this isn't a single-operand MDNode.
auto *N = dyn_cast<MDNode>(MD);
if (!N || N->getNumOperands() != 1)
return MD;
if (!N->getOperand(0))
// !{}
return MDNode::get(Context, None);
if (auto *C = dyn_cast<ConstantAsMetadata>(N->getOperand(0)))
// Look through the MDNode.
return C;
return MD;
}
MetadataAsValue *MetadataAsValue::get(LLVMContext &Context, Metadata *MD) {
MD = canonicalizeMetadataForValue(Context, MD);
auto *&Entry = Context.pImpl->MetadataAsValues[MD];
if (!Entry)
Entry = new MetadataAsValue(Type::getMetadataTy(Context), MD);
return Entry;
}
MetadataAsValue *MetadataAsValue::getIfExists(LLVMContext &Context,
Metadata *MD) {
MD = canonicalizeMetadataForValue(Context, MD);
auto &Store = Context.pImpl->MetadataAsValues;
auto I = Store.find(MD);
return I == Store.end() ? nullptr : I->second;
}
void MetadataAsValue::handleChangedMetadata(Metadata *MD) {
LLVMContext &Context = getContext();
MD = canonicalizeMetadataForValue(Context, MD);
auto &Store = Context.pImpl->MetadataAsValues;
// Stop tracking the old metadata.
Store.erase(this->MD);
untrack();
this->MD = nullptr;
// Start tracking MD, or RAUW if necessary.
auto *&Entry = Store[MD];
if (Entry) {
replaceAllUsesWith(Entry);
delete this;
return;
}
this->MD = MD;
track();
Entry = this;
}
void MetadataAsValue::track() {
if (MD)
MetadataTracking::track(&MD, *MD, *this);
}
void MetadataAsValue::untrack() {
if (MD)
MetadataTracking::untrack(MD);
}
void ReplaceableMetadataImpl::addRef(void *Ref, OwnerTy Owner) {
bool WasInserted =
UseMap.insert(std::make_pair(Ref, std::make_pair(Owner, NextIndex)))
.second;
(void)WasInserted;
assert(WasInserted && "Expected to add a reference");
++NextIndex;
assert(NextIndex != 0 && "Unexpected overflow");
}
void ReplaceableMetadataImpl::dropRef(void *Ref) {
bool WasErased = UseMap.erase(Ref);
(void)WasErased;
assert(WasErased && "Expected to drop a reference");
}
void ReplaceableMetadataImpl::moveRef(void *Ref, void *New,
const Metadata &MD) {
auto I = UseMap.find(Ref);
assert(I != UseMap.end() && "Expected to move a reference");
auto OwnerAndIndex = I->second;
UseMap.erase(I);
bool WasInserted = UseMap.insert(std::make_pair(New, OwnerAndIndex)).second;
(void)WasInserted;
assert(WasInserted && "Expected to add a reference");
// Check that the references are direct if there's no owner.
(void)MD;
assert((OwnerAndIndex.first || *static_cast<Metadata **>(Ref) == &MD) &&
"Reference without owner must be direct");
assert((OwnerAndIndex.first || *static_cast<Metadata **>(New) == &MD) &&
"Reference without owner must be direct");
}
void ReplaceableMetadataImpl::replaceAllUsesWith(Metadata *MD) {
assert(!(MD && isa<MDNodeFwdDecl>(MD)) && "Expected non-temp node");
if (UseMap.empty())
return;
// Copy out uses since UseMap will get touched below.
typedef std::pair<void *, std::pair<OwnerTy, uint64_t>> UseTy;
SmallVector<UseTy, 8> Uses(UseMap.begin(), UseMap.end());
std::sort(Uses.begin(), Uses.end(), [](const UseTy &L, const UseTy &R) {
return L.second.second < R.second.second;
});
for (const auto &Pair : Uses) {
OwnerTy Owner = Pair.second.first;
if (!Owner) {
// Update unowned tracking references directly.
Metadata *&Ref = *static_cast<Metadata **>(Pair.first);
Ref = MD;
if (MD)
MetadataTracking::track(Ref);
UseMap.erase(Pair.first);
continue;
}
// Check for MetadataAsValue.
if (Owner.is<MetadataAsValue *>()) {
Owner.get<MetadataAsValue *>()->handleChangedMetadata(MD);
continue;
}
// There's a Metadata owner -- dispatch.
Metadata *OwnerMD = Owner.get<Metadata *>();
switch (OwnerMD->getMetadataID()) {
#define HANDLE_METADATA_LEAF(CLASS) \
case Metadata::CLASS##Kind: \
cast<CLASS>(OwnerMD)->handleChangedOperand(Pair.first, MD); \
continue;
#include "llvm/IR/Metadata.def"
default:
llvm_unreachable("Invalid metadata subclass");
}
}
assert(UseMap.empty() && "Expected all uses to be replaced");
}
void ReplaceableMetadataImpl::resolveAllUses(bool ResolveUsers) {
if (UseMap.empty())
return;
if (!ResolveUsers) {
UseMap.clear();
return;
}
// Copy out uses since UseMap could get touched below.
typedef std::pair<void *, std::pair<OwnerTy, uint64_t>> UseTy;
SmallVector<UseTy, 8> Uses(UseMap.begin(), UseMap.end());
std::sort(Uses.begin(), Uses.end(), [](const UseTy &L, const UseTy &R) {
return L.second.second < R.second.second;
});
UseMap.clear();
for (const auto &Pair : Uses) {
auto Owner = Pair.second.first;
if (!Owner)
continue;
if (Owner.is<MetadataAsValue *>())
continue;
// Resolve GenericMDNodes that point at this.
auto *OwnerMD = dyn_cast<GenericMDNode>(Owner.get<Metadata *>());
if (!OwnerMD)
continue;
if (OwnerMD->isResolved())
continue;
OwnerMD->decrementUnresolvedOperands();
if (!OwnerMD->hasUnresolvedOperands())
OwnerMD->resolve();
}
}
static Function *getLocalFunction(Value *V) {
assert(V && "Expected value");
if (auto *A = dyn_cast<Argument>(V))
return A->getParent();
if (BasicBlock *BB = cast<Instruction>(V)->getParent())
return BB->getParent();
return nullptr;
}
ValueAsMetadata *ValueAsMetadata::get(Value *V) {
assert(V && "Unexpected null Value");
auto &Context = V->getContext();
auto *&Entry = Context.pImpl->ValuesAsMetadata[V];
if (!Entry) {
assert((isa<Constant>(V) || isa<Argument>(V) || isa<Instruction>(V)) &&
"Expected constant or function-local value");
assert(!V->NameAndIsUsedByMD.getInt() &&
"Expected this to be the only metadata use");
V->NameAndIsUsedByMD.setInt(true);
if (auto *C = dyn_cast<Constant>(V))
Entry = new ConstantAsMetadata(Context, C);
else
Entry = new LocalAsMetadata(Context, V);
}
return Entry;
}
ValueAsMetadata *ValueAsMetadata::getIfExists(Value *V) {
assert(V && "Unexpected null Value");
return V->getContext().pImpl->ValuesAsMetadata.lookup(V);
}
void ValueAsMetadata::handleDeletion(Value *V) {
assert(V && "Expected valid value");
auto &Store = V->getType()->getContext().pImpl->ValuesAsMetadata;
auto I = Store.find(V);
if (I == Store.end())
return;
// Remove old entry from the map.
ValueAsMetadata *MD = I->second;
assert(MD && "Expected valid metadata");
assert(MD->getValue() == V && "Expected valid mapping");
Store.erase(I);
// Delete the metadata.
MD->replaceAllUsesWith(nullptr);
delete MD;
}
void ValueAsMetadata::handleRAUW(Value *From, Value *To) {
assert(From && "Expected valid value");
assert(To && "Expected valid value");
assert(From != To && "Expected changed value");
assert(From->getType() == To->getType() && "Unexpected type change");
LLVMContext &Context = From->getType()->getContext();
auto &Store = Context.pImpl->ValuesAsMetadata;
auto I = Store.find(From);
if (I == Store.end()) {
assert(!From->NameAndIsUsedByMD.getInt() &&
"Expected From not to be used by metadata");
return;
}
// Remove old entry from the map.
assert(From->NameAndIsUsedByMD.getInt() &&
"Expected From to be used by metadata");
From->NameAndIsUsedByMD.setInt(false);
ValueAsMetadata *MD = I->second;
assert(MD && "Expected valid metadata");
assert(MD->getValue() == From && "Expected valid mapping");
Store.erase(I);
if (isa<LocalAsMetadata>(MD)) {
if (auto *C = dyn_cast<Constant>(To)) {
// Local became a constant.
MD->replaceAllUsesWith(ConstantAsMetadata::get(C));
delete MD;
return;
}
if (getLocalFunction(From) && getLocalFunction(To) &&
getLocalFunction(From) != getLocalFunction(To)) {
// Function changed.
MD->replaceAllUsesWith(nullptr);
delete MD;
return;
}
} else if (!isa<Constant>(To)) {
// Changed to function-local value.
MD->replaceAllUsesWith(nullptr);
delete MD;
return;
}
auto *&Entry = Store[To];
if (Entry) {
// The target already exists.
MD->replaceAllUsesWith(Entry);
delete MD;
return;
}
// Update MD in place (and update the map entry).
assert(!To->NameAndIsUsedByMD.getInt() &&
"Expected this to be the only metadata use");
To->NameAndIsUsedByMD.setInt(true);
MD->V = To;
Entry = MD;
}
//===----------------------------------------------------------------------===//
// MDString implementation.
//
MDString *MDString::get(LLVMContext &Context, StringRef Str) {
auto &Store = Context.pImpl->MDStringCache;
auto I = Store.find(Str);
if (I != Store.end())
return &I->second;
auto *Entry =
StringMapEntry<MDString>::Create(Str, Store.getAllocator(), MDString());
bool WasInserted = Store.insert(Entry);
(void)WasInserted;
assert(WasInserted && "Expected entry to be inserted");
Entry->second.Entry = Entry;
return &Entry->second;
}
StringRef MDString::getString() const {
assert(Entry && "Expected to find string map entry");
return Entry->first();
}
//===----------------------------------------------------------------------===//
// MDNode implementation.
//
void *MDNode::operator new(size_t Size, unsigned NumOps) {
void *Ptr = ::operator new(Size + NumOps * sizeof(MDOperand));
MDOperand *O = static_cast<MDOperand *>(Ptr);
for (MDOperand *E = O + NumOps; O != E; ++O)
(void)new (O) MDOperand;
return O;
}
void MDNode::operator delete(void *Mem) {
MDNode *N = static_cast<MDNode *>(Mem);
MDOperand *O = static_cast<MDOperand *>(Mem);
for (MDOperand *E = O - N->NumOperands; O != E; --O)
(O - 1)->~MDOperand();
::operator delete(O);
}
MDNode::MDNode(LLVMContext &Context, unsigned ID, ArrayRef<Metadata *> MDs)
: Metadata(ID), Context(Context), NumOperands(MDs.size()),
MDNodeSubclassData(0) {
for (unsigned I = 0, E = MDs.size(); I != E; ++I)
setOperand(I, MDs[I]);
}
bool MDNode::isResolved() const {
if (isa<MDNodeFwdDecl>(this))
return false;
return cast<GenericMDNode>(this)->isResolved();
}
static bool isOperandUnresolved(Metadata *Op) {
if (auto *N = dyn_cast_or_null<MDNode>(Op))
return !N->isResolved();
return false;
}
GenericMDNode::GenericMDNode(LLVMContext &C, ArrayRef<Metadata *> Vals)
: MDNode(C, GenericMDNodeKind, Vals) {
// Check whether any operands are unresolved, requiring re-uniquing.
for (const auto &Op : operands())
if (isOperandUnresolved(Op))
incrementUnresolvedOperands();
if (hasUnresolvedOperands())
ReplaceableUses.reset(new ReplaceableMetadataImpl);
}
GenericMDNode::~GenericMDNode() {
LLVMContextImpl *pImpl = getContext().pImpl;
if (isStoredDistinctInContext())
pImpl->NonUniquedMDNodes.erase(this);
else
pImpl->MDNodeSet.erase(this);
dropAllReferences();
}
void GenericMDNode::resolve() {
assert(!isResolved() && "Expected this to be unresolved");
// Move the map, so that this immediately looks resolved.
auto Uses = std::move(ReplaceableUses);
SubclassData32 = 0;
assert(isResolved() && "Expected this to be resolved");
// Drop RAUW support.
Uses->resolveAllUses();
}
void GenericMDNode::resolveCycles() {
if (isResolved())
return;
// Resolve this node immediately.
resolve();
// Resolve all operands.
for (const auto &Op : operands()) {
if (!Op)
continue;
assert(!isa<MDNodeFwdDecl>(Op) &&
"Expected all forward declarations to be resolved");
if (auto *N = dyn_cast<GenericMDNode>(Op))
if (!N->isResolved())
N->resolveCycles();
}
}
void MDNode::dropAllReferences() {
for (unsigned I = 0, E = NumOperands; I != E; ++I)
setOperand(I, nullptr);
if (auto *G = dyn_cast<GenericMDNode>(this))
if (!G->isResolved()) {
G->ReplaceableUses->resolveAllUses(/* ResolveUsers */ false);
G->ReplaceableUses.reset();
}
}
namespace llvm {
/// \brief Make MDOperand transparent for hashing.
///
/// This overload of an implementation detail of the hashing library makes
/// MDOperand hash to the same value as a \a Metadata pointer.
///
/// Note that overloading \a hash_value() as follows:
///
/// \code
/// size_t hash_value(const MDOperand &X) { return hash_value(X.get()); }
/// \endcode
///
/// does not cause MDOperand to be transparent. In particular, a bare pointer
/// doesn't get hashed before it's combined, whereas \a MDOperand would.
static const Metadata *get_hashable_data(const MDOperand &X) { return X.get(); }
}
void GenericMDNode::handleChangedOperand(void *Ref, Metadata *New) {
unsigned Op = static_cast<MDOperand *>(Ref) - op_begin();
assert(Op < getNumOperands() && "Expected valid operand");
if (isStoredDistinctInContext()) {
assert(isResolved() && "Expected distinct node to be resolved");
// This node is not uniqued. Just set the operand and be done with it.
setOperand(Op, New);
return;
}
if (InRAUW) {
// We just hit a recursion due to RAUW. Set the operand and move on, since
// we're about to be deleted.
//
// FIXME: Can this cycle really happen?
setOperand(Op, New);
return;
}
auto &Store = getContext().pImpl->MDNodeSet;
Store.erase(this);
Metadata *Old = getOperand(Op);
setOperand(Op, New);
// Drop uniquing for self-reference cycles or if an operand drops to null.
//
// FIXME: Stop dropping uniquing when an operand drops to null. The original
// motivation was to prevent madness during teardown of LLVMContextImpl, but
// dropAllReferences() fixes that problem in a better way. (It's just here
// now for better staging of semantic changes.)
if (New == this || !New) {
storeDistinctInContext();
setHash(0);
if (!isResolved())
resolve();
return;
}
// Re-calculate the hash.
setHash(hash_combine_range(op_begin(), op_end()));
#ifndef NDEBUG
{
SmallVector<Metadata *, 8> MDs(op_begin(), op_end());
unsigned RawHash = hash_combine_range(MDs.begin(), MDs.end());
assert(getHash() == RawHash &&
"Expected hash of MDOperand to equal hash of Metadata*");
}
#endif
// Re-unique the node.
GenericMDNodeInfo::KeyTy Key(this);
auto I = Store.find_as(Key);
if (I == Store.end()) {
Store.insert(this);
if (!isResolved()) {
// Check if the last unresolved operand has just been resolved; if so,
// resolve this as well.
if (isOperandUnresolved(Old))
decrementUnresolvedOperands();
if (isOperandUnresolved(New))
incrementUnresolvedOperands();
if (!hasUnresolvedOperands())
resolve();
}
return;
}
// Collision.
if (!isResolved()) {
// Still unresolved, so RAUW.
InRAUW = true;
ReplaceableUses->replaceAllUsesWith(*I);
delete this;
return;
}
// Store in non-uniqued form if this node has already been resolved.
setHash(0);
storeDistinctInContext();
}
MDNode *MDNode::getMDNode(LLVMContext &Context, ArrayRef<Metadata *> MDs,
bool Insert) {
auto &Store = Context.pImpl->MDNodeSet;
GenericMDNodeInfo::KeyTy Key(MDs);
auto I = Store.find_as(Key);
if (I != Store.end())
return *I;
if (!Insert)
return nullptr;
// Coallocate space for the node and Operands together, then placement new.
GenericMDNode *N = new (MDs.size()) GenericMDNode(Context, MDs);
N->setHash(Key.Hash);
Store.insert(N);
return N;
}
MDNodeFwdDecl *MDNode::getTemporary(LLVMContext &Context,
ArrayRef<Metadata *> MDs) {
MDNodeFwdDecl *N = new (MDs.size()) MDNodeFwdDecl(Context, MDs);
LeakDetector::addGarbageObject(N);
return N;
}
void MDNode::deleteTemporary(MDNode *N) {
assert(isa<MDNodeFwdDecl>(N) && "Expected forward declaration");
LeakDetector::removeGarbageObject(N);
delete cast<MDNodeFwdDecl>(N);
}
void MDNode::storeDistinctInContext() {
assert(!IsDistinctInContext && "Expected newly distinct metadata");
IsDistinctInContext = true;
auto *G = cast<GenericMDNode>(this);
G->setHash(0);
getContext().pImpl->NonUniquedMDNodes.insert(G);
}
// Replace value from this node's operand list.
void MDNode::replaceOperandWith(unsigned I, Metadata *New) {
if (getOperand(I) == New)
return;
if (auto *N = dyn_cast<GenericMDNode>(this)) {
N->handleChangedOperand(mutable_begin() + I, New);
return;
}
assert(isa<MDNodeFwdDecl>(this) && "Expected an MDNode");
setOperand(I, New);
}
void MDNode::setOperand(unsigned I, Metadata *New) {
assert(I < NumOperands);
if (isStoredDistinctInContext() || isa<MDNodeFwdDecl>(this))
// No need for a callback, this isn't uniqued.
mutable_begin()[I].reset(New, nullptr);
else
mutable_begin()[I].reset(New, this);
}
/// \brief Get a node, or a self-reference that looks like it.
///
/// Special handling for finding self-references, for use by \a
/// MDNode::concatenate() and \a MDNode::intersect() to maintain behaviour from
/// when self-referencing nodes were still uniqued. If the first operand has
/// the same operands as \c Ops, return the first operand instead.
static MDNode *getOrSelfReference(LLVMContext &Context,
ArrayRef<Metadata *> Ops) {
if (!Ops.empty())
if (MDNode *N = dyn_cast_or_null<MDNode>(Ops[0]))
if (N->getNumOperands() == Ops.size() && N == N->getOperand(0)) {
for (unsigned I = 1, E = Ops.size(); I != E; ++I)
if (Ops[I] != N->getOperand(I))
return MDNode::get(Context, Ops);
return N;
}
return MDNode::get(Context, Ops);
}
MDNode *MDNode::concatenate(MDNode *A, MDNode *B) {
if (!A)
return B;
if (!B)
return A;
SmallVector<Metadata *, 4> MDs(A->getNumOperands() + B->getNumOperands());
unsigned j = 0;
for (unsigned i = 0, ie = A->getNumOperands(); i != ie; ++i)
MDs[j++] = A->getOperand(i);
for (unsigned i = 0, ie = B->getNumOperands(); i != ie; ++i)
MDs[j++] = B->getOperand(i);
// FIXME: This preserves long-standing behaviour, but is it really the right
// behaviour? Or was that an unintended side-effect of node uniquing?
return getOrSelfReference(A->getContext(), MDs);
}
MDNode *MDNode::intersect(MDNode *A, MDNode *B) {
if (!A || !B)
return nullptr;
SmallVector<Metadata *, 4> MDs;
for (unsigned i = 0, ie = A->getNumOperands(); i != ie; ++i) {
Metadata *MD = A->getOperand(i);
for (unsigned j = 0, je = B->getNumOperands(); j != je; ++j)
if (MD == B->getOperand(j)) {
MDs.push_back(MD);
break;
}
}
// FIXME: This preserves long-standing behaviour, but is it really the right
// behaviour? Or was that an unintended side-effect of node uniquing?
return getOrSelfReference(A->getContext(), MDs);
}
MDNode *MDNode::getMostGenericFPMath(MDNode *A, MDNode *B) {
if (!A || !B)
return nullptr;
APFloat AVal = mdconst::extract<ConstantFP>(A->getOperand(0))->getValueAPF();
APFloat BVal = mdconst::extract<ConstantFP>(B->getOperand(0))->getValueAPF();
if (AVal.compare(BVal) == APFloat::cmpLessThan)
return A;
return B;
}
static bool isContiguous(const ConstantRange &A, const ConstantRange &B) {
return A.getUpper() == B.getLower() || A.getLower() == B.getUpper();
}
static bool canBeMerged(const ConstantRange &A, const ConstantRange &B) {
return !A.intersectWith(B).isEmptySet() || isContiguous(A, B);
}
static bool tryMergeRange(SmallVectorImpl<ConstantInt *> &EndPoints,
ConstantInt *Low, ConstantInt *High) {
ConstantRange NewRange(Low->getValue(), High->getValue());
unsigned Size = EndPoints.size();
APInt LB = EndPoints[Size - 2]->getValue();
APInt LE = EndPoints[Size - 1]->getValue();
ConstantRange LastRange(LB, LE);
if (canBeMerged(NewRange, LastRange)) {
ConstantRange Union = LastRange.unionWith(NewRange);
Type *Ty = High->getType();
EndPoints[Size - 2] =
cast<ConstantInt>(ConstantInt::get(Ty, Union.getLower()));
EndPoints[Size - 1] =
cast<ConstantInt>(ConstantInt::get(Ty, Union.getUpper()));
return true;
}
return false;
}
static void addRange(SmallVectorImpl<ConstantInt *> &EndPoints,
ConstantInt *Low, ConstantInt *High) {
if (!EndPoints.empty())
if (tryMergeRange(EndPoints, Low, High))
return;
EndPoints.push_back(Low);
EndPoints.push_back(High);
}
MDNode *MDNode::getMostGenericRange(MDNode *A, MDNode *B) {
// Given two ranges, we want to compute the union of the ranges. This
// is slightly complitade by having to combine the intervals and merge
// the ones that overlap.
if (!A || !B)
return nullptr;
if (A == B)
return A;
// First, walk both lists in older of the lower boundary of each interval.
// At each step, try to merge the new interval to the last one we adedd.
SmallVector<ConstantInt *, 4> EndPoints;
int AI = 0;
int BI = 0;
int AN = A->getNumOperands() / 2;
int BN = B->getNumOperands() / 2;
while (AI < AN && BI < BN) {
ConstantInt *ALow = mdconst::extract<ConstantInt>(A->getOperand(2 * AI));
ConstantInt *BLow = mdconst::extract<ConstantInt>(B->getOperand(2 * BI));
if (ALow->getValue().slt(BLow->getValue())) {
addRange(EndPoints, ALow,
mdconst::extract<ConstantInt>(A->getOperand(2 * AI + 1)));
++AI;
} else {
addRange(EndPoints, BLow,
mdconst::extract<ConstantInt>(B->getOperand(2 * BI + 1)));
++BI;
}
}
while (AI < AN) {
addRange(EndPoints, mdconst::extract<ConstantInt>(A->getOperand(2 * AI)),
mdconst::extract<ConstantInt>(A->getOperand(2 * AI + 1)));
++AI;
}
while (BI < BN) {
addRange(EndPoints, mdconst::extract<ConstantInt>(B->getOperand(2 * BI)),
mdconst::extract<ConstantInt>(B->getOperand(2 * BI + 1)));
++BI;
}
// If we have more than 2 ranges (4 endpoints) we have to try to merge
// the last and first ones.
unsigned Size = EndPoints.size();
if (Size > 4) {
ConstantInt *FB = EndPoints[0];
ConstantInt *FE = EndPoints[1];
if (tryMergeRange(EndPoints, FB, FE)) {
for (unsigned i = 0; i < Size - 2; ++i) {
EndPoints[i] = EndPoints[i + 2];
}
EndPoints.resize(Size - 2);
}
}
// If in the end we have a single range, it is possible that it is now the
// full range. Just drop the metadata in that case.
if (EndPoints.size() == 2) {
ConstantRange Range(EndPoints[0]->getValue(), EndPoints[1]->getValue());
if (Range.isFullSet())
return nullptr;
}
SmallVector<Metadata *, 4> MDs;
MDs.reserve(EndPoints.size());
for (auto *I : EndPoints)
MDs.push_back(ConstantAsMetadata::get(I));
return MDNode::get(A->getContext(), MDs);
}
//===----------------------------------------------------------------------===//
// NamedMDNode implementation.
//
static SmallVector<TrackingMDRef, 4> &getNMDOps(void *Operands) {
return *(SmallVector<TrackingMDRef, 4> *)Operands;
}
NamedMDNode::NamedMDNode(const Twine &N)
: Name(N.str()), Parent(nullptr),
Operands(new SmallVector<TrackingMDRef, 4>()) {}
NamedMDNode::~NamedMDNode() {
dropAllReferences();
delete &getNMDOps(Operands);
}
unsigned NamedMDNode::getNumOperands() const {
return (unsigned)getNMDOps(Operands).size();
}
MDNode *NamedMDNode::getOperand(unsigned i) const {
assert(i < getNumOperands() && "Invalid Operand number!");
auto *N = getNMDOps(Operands)[i].get();
if (N && i > 10000)
N->dump();
return cast_or_null<MDNode>(N);
}
void NamedMDNode::addOperand(MDNode *M) { getNMDOps(Operands).emplace_back(M); }
void NamedMDNode::eraseFromParent() {
getParent()->eraseNamedMetadata(this);
}
void NamedMDNode::dropAllReferences() {
getNMDOps(Operands).clear();
}
StringRef NamedMDNode::getName() const {
return StringRef(Name);
}
//===----------------------------------------------------------------------===//
// Instruction Metadata method implementations.
//
void Instruction::setMetadata(StringRef Kind, MDNode *Node) {
if (!Node && !hasMetadata())
return;
setMetadata(getContext().getMDKindID(Kind), Node);
}
MDNode *Instruction::getMetadataImpl(StringRef Kind) const {
return getMetadataImpl(getContext().getMDKindID(Kind));
}
void Instruction::dropUnknownMetadata(ArrayRef<unsigned> KnownIDs) {
SmallSet<unsigned, 5> KnownSet;
KnownSet.insert(KnownIDs.begin(), KnownIDs.end());
// Drop debug if needed
if (KnownSet.erase(LLVMContext::MD_dbg))
DbgLoc = DebugLoc();
if (!hasMetadataHashEntry())
return; // Nothing to remove!
DenseMap<const Instruction *, LLVMContextImpl::MDMapTy> &MetadataStore =
getContext().pImpl->MetadataStore;
if (KnownSet.empty()) {
// Just drop our entry at the store.
MetadataStore.erase(this);
setHasMetadataHashEntry(false);
return;
}
LLVMContextImpl::MDMapTy &Info = MetadataStore[this];
unsigned I;
unsigned E;
// Walk the array and drop any metadata we don't know.
for (I = 0, E = Info.size(); I != E;) {
if (KnownSet.count(Info[I].first)) {
++I;
continue;
}
Info[I] = std::move(Info.back());
Info.pop_back();
--E;
}
assert(E == Info.size());
if (E == 0) {
// Drop our entry at the store.
MetadataStore.erase(this);
setHasMetadataHashEntry(false);
}
}
/// setMetadata - Set the metadata of of the specified kind to the specified
/// node. This updates/replaces metadata if already present, or removes it if
/// Node is null.
void Instruction::setMetadata(unsigned KindID, MDNode *Node) {
if (!Node && !hasMetadata())
return;
// Handle 'dbg' as a special case since it is not stored in the hash table.
if (KindID == LLVMContext::MD_dbg) {
DbgLoc = DebugLoc::getFromDILocation(Node);
return;
}
// Handle the case when we're adding/updating metadata on an instruction.
if (Node) {
LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
assert(!Info.empty() == hasMetadataHashEntry() &&
"HasMetadata bit is wonked");
if (Info.empty()) {
setHasMetadataHashEntry(true);
} else {
// Handle replacement of an existing value.
for (auto &P : Info)
if (P.first == KindID) {
P.second.reset(Node);
return;
}
}
// No replacement, just add it to the list.
Info.emplace_back(std::piecewise_construct, std::make_tuple(KindID),
std::make_tuple(Node));
return;
}
// Otherwise, we're removing metadata from an instruction.
assert((hasMetadataHashEntry() ==
(getContext().pImpl->MetadataStore.count(this) > 0)) &&
"HasMetadata bit out of date!");
if (!hasMetadataHashEntry())
return; // Nothing to remove!
LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
// Common case is removing the only entry.
if (Info.size() == 1 && Info[0].first == KindID) {
getContext().pImpl->MetadataStore.erase(this);
setHasMetadataHashEntry(false);
return;
}
// Handle removal of an existing value.
for (unsigned i = 0, e = Info.size(); i != e; ++i)
if (Info[i].first == KindID) {
Info[i] = std::move(Info.back());
Info.pop_back();
assert(!Info.empty() && "Removing last entry should be handled above");
return;
}
// Otherwise, removing an entry that doesn't exist on the instruction.
}
void Instruction::setAAMetadata(const AAMDNodes &N) {
setMetadata(LLVMContext::MD_tbaa, N.TBAA);
setMetadata(LLVMContext::MD_alias_scope, N.Scope);
setMetadata(LLVMContext::MD_noalias, N.NoAlias);
}
MDNode *Instruction::getMetadataImpl(unsigned KindID) const {
// Handle 'dbg' as a special case since it is not stored in the hash table.
if (KindID == LLVMContext::MD_dbg)
return DbgLoc.getAsMDNode();
if (!hasMetadataHashEntry()) return nullptr;
LLVMContextImpl::MDMapTy &Info = getContext().pImpl->MetadataStore[this];
assert(!Info.empty() && "bit out of sync with hash table");
for (const auto &I : Info)
if (I.first == KindID)
return I.second;
return nullptr;
}
void Instruction::getAllMetadataImpl(
SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
Result.clear();
// Handle 'dbg' as a special case since it is not stored in the hash table.
if (!DbgLoc.isUnknown()) {
Result.push_back(
std::make_pair((unsigned)LLVMContext::MD_dbg, DbgLoc.getAsMDNode()));
if (!hasMetadataHashEntry()) return;
}
assert(hasMetadataHashEntry() &&
getContext().pImpl->MetadataStore.count(this) &&
"Shouldn't have called this");
const LLVMContextImpl::MDMapTy &Info =
getContext().pImpl->MetadataStore.find(this)->second;
assert(!Info.empty() && "Shouldn't have called this");
Result.reserve(Result.size() + Info.size());
for (auto &I : Info)
Result.push_back(std::make_pair(I.first, cast<MDNode>(I.second.get())));
// Sort the resulting array so it is stable.
if (Result.size() > 1)
array_pod_sort(Result.begin(), Result.end());
}
void Instruction::getAllMetadataOtherThanDebugLocImpl(
SmallVectorImpl<std::pair<unsigned, MDNode *>> &Result) const {
Result.clear();
assert(hasMetadataHashEntry() &&
getContext().pImpl->MetadataStore.count(this) &&
"Shouldn't have called this");
const LLVMContextImpl::MDMapTy &Info =
getContext().pImpl->MetadataStore.find(this)->second;
assert(!Info.empty() && "Shouldn't have called this");
Result.reserve(Result.size() + Info.size());
for (auto &I : Info)
Result.push_back(std::make_pair(I.first, cast<MDNode>(I.second.get())));
// Sort the resulting array so it is stable.
if (Result.size() > 1)
array_pod_sort(Result.begin(), Result.end());
}
/// clearMetadataHashEntries - Clear all hashtable-based metadata from
/// this instruction.
void Instruction::clearMetadataHashEntries() {
assert(hasMetadataHashEntry() && "Caller should check");
getContext().pImpl->MetadataStore.erase(this);
setHasMetadataHashEntry(false);
}