#ifndef LLVM_ANALYSIS_ALIASSETTRACKER_H
#define LLVM_ANALYSIS_ALIASSETTRACKER_H
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/ilist.h"
#include "llvm/ADT/ilist_node.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/ValueHandle.h"
#include <vector>
namespace llvm {
class LoadInst;
class StoreInst;
class VAArgInst;
class AliasSetTracker;
class AliasSet;
class AliasSet : public ilist_node<AliasSet> {
friend class AliasSetTracker;
class PointerRec {
Value *Val; PointerRec **PrevInList, *NextInList;
AliasSet *AS;
uint64_t Size;
AAMDNodes AAInfo;
public:
PointerRec(Value *V)
: Val(V), PrevInList(nullptr), NextInList(nullptr), AS(nullptr), Size(0),
AAInfo(DenseMapInfo<AAMDNodes>::getEmptyKey()) {}
Value *getValue() const { return Val; }
PointerRec *getNext() const { return NextInList; }
bool hasAliasSet() const { return AS != nullptr; }
PointerRec** setPrevInList(PointerRec **PIL) {
PrevInList = PIL;
return &NextInList;
}
void updateSizeAndAAInfo(uint64_t NewSize, const AAMDNodes &NewAAInfo) {
if (NewSize > Size) Size = NewSize;
if (AAInfo == DenseMapInfo<AAMDNodes>::getEmptyKey())
AAInfo = NewAAInfo;
else if (AAInfo != NewAAInfo)
AAInfo = DenseMapInfo<AAMDNodes>::getTombstoneKey();
}
uint64_t getSize() const { return Size; }
AAMDNodes getAAInfo() const {
if (AAInfo == DenseMapInfo<AAMDNodes>::getEmptyKey() ||
AAInfo == DenseMapInfo<AAMDNodes>::getTombstoneKey())
return AAMDNodes();
return AAInfo;
}
AliasSet *getAliasSet(AliasSetTracker &AST) {
assert(AS && "No AliasSet yet!");
if (AS->Forward) {
AliasSet *OldAS = AS;
AS = OldAS->getForwardedTarget(AST);
AS->addRef();
OldAS->dropRef(AST);
}
return AS;
}
void setAliasSet(AliasSet *as) {
assert(!AS && "Already have an alias set!");
AS = as;
}
void eraseFromList() {
if (NextInList) NextInList->PrevInList = PrevInList;
*PrevInList = NextInList;
if (AS->PtrListEnd == &NextInList) {
AS->PtrListEnd = PrevInList;
assert(*AS->PtrListEnd == nullptr && "List not terminated right!");
}
delete this;
}
};
PointerRec *PtrList, **PtrListEnd; AliasSet *Forward;
std::vector<AssertingVH<Instruction> > UnknownInsts;
unsigned RefCount : 28;
enum AccessLattice {
NoAccess = 0,
RefAccess = 1,
ModAccess = 2,
ModRefAccess = RefAccess | ModAccess
};
unsigned Access : 2;
enum AliasLattice {
SetMustAlias = 0, SetMayAlias = 1
};
unsigned Alias : 1;
bool Volatile : 1;
void addRef() { ++RefCount; }
void dropRef(AliasSetTracker &AST) {
assert(RefCount >= 1 && "Invalid reference count detected!");
if (--RefCount == 0)
removeFromTracker(AST);
}
Instruction *getUnknownInst(unsigned i) const {
assert(i < UnknownInsts.size());
return UnknownInsts[i];
}
public:
bool isRef() const { return Access & RefAccess; }
bool isMod() const { return Access & ModAccess; }
bool isMustAlias() const { return Alias == SetMustAlias; }
bool isMayAlias() const { return Alias == SetMayAlias; }
bool isVolatile() const { return Volatile; }
bool isForwardingAliasSet() const { return Forward; }
void mergeSetIn(AliasSet &AS, AliasSetTracker &AST);
class iterator;
iterator begin() const { return iterator(PtrList); }
iterator end() const { return iterator(); }
bool empty() const { return PtrList == nullptr; }
void print(raw_ostream &OS) const;
void dump() const;
class iterator : public std::iterator<std::forward_iterator_tag,
PointerRec, ptrdiff_t> {
PointerRec *CurNode;
public:
explicit iterator(PointerRec *CN = nullptr) : CurNode(CN) {}
bool operator==(const iterator& x) const {
return CurNode == x.CurNode;
}
bool operator!=(const iterator& x) const { return !operator==(x); }
value_type &operator*() const {
assert(CurNode && "Dereferencing AliasSet.end()!");
return *CurNode;
}
value_type *operator->() const { return &operator*(); }
Value *getPointer() const { return CurNode->getValue(); }
uint64_t getSize() const { return CurNode->getSize(); }
AAMDNodes getAAInfo() const { return CurNode->getAAInfo(); }
iterator& operator++() { assert(CurNode && "Advancing past AliasSet.end()!");
CurNode = CurNode->getNext();
return *this;
}
iterator operator++(int) { iterator tmp = *this; ++*this; return tmp;
}
};
private:
friend struct ilist_sentinel_traits<AliasSet>;
AliasSet()
: PtrList(nullptr), PtrListEnd(&PtrList), Forward(nullptr), RefCount(0),
Access(NoAccess), Alias(SetMustAlias), Volatile(false) {
}
AliasSet(const AliasSet &AS) = delete;
void operator=(const AliasSet &AS) = delete;
PointerRec *getSomePointer() const {
return PtrList;
}
AliasSet *getForwardedTarget(AliasSetTracker &AST) {
if (!Forward) return this;
AliasSet *Dest = Forward->getForwardedTarget(AST);
if (Dest != Forward) {
Dest->addRef();
Forward->dropRef(AST);
Forward = Dest;
}
return Dest;
}
void removeFromTracker(AliasSetTracker &AST);
void addPointer(AliasSetTracker &AST, PointerRec &Entry, uint64_t Size,
const AAMDNodes &AAInfo,
bool KnownMustAlias = false);
void addUnknownInst(Instruction *I, AliasAnalysis &AA);
void removeUnknownInst(AliasSetTracker &AST, Instruction *I) {
bool WasEmpty = UnknownInsts.empty();
for (size_t i = 0, e = UnknownInsts.size(); i != e; ++i)
if (UnknownInsts[i] == I) {
UnknownInsts[i] = UnknownInsts.back();
UnknownInsts.pop_back();
--i; --e; }
if (!WasEmpty && UnknownInsts.empty())
dropRef(AST);
}
void setVolatile() { Volatile = true; }
public:
bool aliasesPointer(const Value *Ptr, uint64_t Size, const AAMDNodes &AAInfo,
AliasAnalysis &AA) const;
bool aliasesUnknownInst(const Instruction *Inst, AliasAnalysis &AA) const;
};
inline raw_ostream& operator<<(raw_ostream &OS, const AliasSet &AS) {
AS.print(OS);
return OS;
}
class AliasSetTracker {
class ASTCallbackVH final : public CallbackVH {
AliasSetTracker *AST;
void deleted() override;
void allUsesReplacedWith(Value *) override;
public:
ASTCallbackVH(Value *V, AliasSetTracker *AST = nullptr);
ASTCallbackVH &operator=(Value *V);
};
struct ASTCallbackVHDenseMapInfo : public DenseMapInfo<Value *> {};
AliasAnalysis &AA;
ilist<AliasSet> AliasSets;
typedef DenseMap<ASTCallbackVH, AliasSet::PointerRec*,
ASTCallbackVHDenseMapInfo>
PointerMapType;
PointerMapType PointerMap;
public:
explicit AliasSetTracker(AliasAnalysis &aa) : AA(aa) {}
~AliasSetTracker() { clear(); }
bool add(Value *Ptr, uint64_t Size, const AAMDNodes &AAInfo); bool add(LoadInst *LI);
bool add(StoreInst *SI);
bool add(VAArgInst *VAAI);
bool add(Instruction *I); void add(BasicBlock &BB); void add(const AliasSetTracker &AST); bool addUnknown(Instruction *I);
bool remove(Value *Ptr, uint64_t Size, const AAMDNodes &AAInfo);
bool remove(LoadInst *LI);
bool remove(StoreInst *SI);
bool remove(VAArgInst *VAAI);
bool remove(Instruction *I);
void remove(AliasSet &AS);
bool removeUnknown(Instruction *I);
void clear();
const ilist<AliasSet> &getAliasSets() const { return AliasSets; }
AliasSet &getAliasSetForPointer(Value *P, uint64_t Size,
const AAMDNodes &AAInfo,
bool *New = nullptr);
AliasSet *getAliasSetForPointerIfExists(const Value *P, uint64_t Size,
const AAMDNodes &AAInfo) {
return findAliasSetForPointer(P, Size, AAInfo);
}
bool containsPointer(const Value *P, uint64_t Size,
const AAMDNodes &AAInfo) const;
bool containsUnknown(const Instruction *I) const;
AliasAnalysis &getAliasAnalysis() const { return AA; }
void deleteValue(Value *PtrVal);
void copyValue(Value *From, Value *To);
typedef ilist<AliasSet>::iterator iterator;
typedef ilist<AliasSet>::const_iterator const_iterator;
const_iterator begin() const { return AliasSets.begin(); }
const_iterator end() const { return AliasSets.end(); }
iterator begin() { return AliasSets.begin(); }
iterator end() { return AliasSets.end(); }
void print(raw_ostream &OS) const;
void dump() const;
private:
friend class AliasSet;
void removeAliasSet(AliasSet *AS);
AliasSet::PointerRec &getEntryFor(Value *V) {
AliasSet::PointerRec *&Entry = PointerMap[ASTCallbackVH(V, this)];
if (!Entry)
Entry = new AliasSet::PointerRec(V);
return *Entry;
}
AliasSet &addPointer(Value *P, uint64_t Size, const AAMDNodes &AAInfo,
AliasSet::AccessLattice E,
bool &NewSet) {
NewSet = false;
AliasSet &AS = getAliasSetForPointer(P, Size, AAInfo, &NewSet);
AS.Access |= E;
return AS;
}
AliasSet *findAliasSetForPointer(const Value *Ptr, uint64_t Size,
const AAMDNodes &AAInfo);
AliasSet *findAliasSetForUnknownInst(Instruction *Inst);
};
inline raw_ostream& operator<<(raw_ostream &OS, const AliasSetTracker &AST) {
AST.print(OS);
return OS;
}
}
#endif