mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-08-30 05:29:47 +00:00
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206243 91177308-0d34-0410-b5e6-96231b3b80d8
439 lines
15 KiB
C++
439 lines
15 KiB
C++
//===- llvm/Analysis/AliasSetTracker.h - Build Alias Sets -------*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file defines two classes: AliasSetTracker and AliasSet. These interface
|
|
// are used to classify a collection of pointer references into a maximal number
|
|
// of disjoint sets. Each AliasSet object constructed by the AliasSetTracker
|
|
// object refers to memory disjoint from the other sets.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#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/IR/ValueHandle.h"
|
|
#include <vector>
|
|
|
|
namespace llvm {
|
|
|
|
class AliasAnalysis;
|
|
class LoadInst;
|
|
class StoreInst;
|
|
class VAArgInst;
|
|
class AliasSetTracker;
|
|
class AliasSet;
|
|
|
|
class AliasSet : public ilist_node<AliasSet> {
|
|
friend class AliasSetTracker;
|
|
|
|
class PointerRec {
|
|
Value *Val; // The pointer this record corresponds to.
|
|
PointerRec **PrevInList, *NextInList;
|
|
AliasSet *AS;
|
|
uint64_t Size;
|
|
const MDNode *TBAAInfo;
|
|
public:
|
|
PointerRec(Value *V)
|
|
: Val(V), PrevInList(nullptr), NextInList(nullptr), AS(nullptr), Size(0),
|
|
TBAAInfo(DenseMapInfo<const MDNode *>::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 updateSizeAndTBAAInfo(uint64_t NewSize, const MDNode *NewTBAAInfo) {
|
|
if (NewSize > Size) Size = NewSize;
|
|
|
|
if (TBAAInfo == DenseMapInfo<const MDNode *>::getEmptyKey())
|
|
// We don't have a TBAAInfo yet. Set it to NewTBAAInfo.
|
|
TBAAInfo = NewTBAAInfo;
|
|
else if (TBAAInfo != NewTBAAInfo)
|
|
// NewTBAAInfo conflicts with TBAAInfo.
|
|
TBAAInfo = DenseMapInfo<const MDNode *>::getTombstoneKey();
|
|
}
|
|
|
|
uint64_t getSize() const { return Size; }
|
|
|
|
/// getTBAAInfo - Return the TBAAInfo, or null if there is no
|
|
/// information or conflicting information.
|
|
const MDNode *getTBAAInfo() const {
|
|
// If we have missing or conflicting TBAAInfo, return null.
|
|
if (TBAAInfo == DenseMapInfo<const MDNode *>::getEmptyKey() ||
|
|
TBAAInfo == DenseMapInfo<const MDNode *>::getTombstoneKey())
|
|
return nullptr;
|
|
return TBAAInfo;
|
|
}
|
|
|
|
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; // Doubly linked list of nodes.
|
|
AliasSet *Forward; // Forwarding pointer.
|
|
|
|
// All instructions without a specific address in this alias set.
|
|
std::vector<AssertingVH<Instruction> > UnknownInsts;
|
|
|
|
// RefCount - Number of nodes pointing to this AliasSet plus the number of
|
|
// AliasSets forwarding to it.
|
|
unsigned RefCount : 28;
|
|
|
|
/// AccessType - Keep track of whether this alias set merely refers to the
|
|
/// locations of memory, whether it modifies the memory, or whether it does
|
|
/// both. The lattice goes from "NoModRef" to either Refs or Mods, then to
|
|
/// ModRef as necessary.
|
|
///
|
|
enum AccessType {
|
|
NoModRef = 0, Refs = 1, // Ref = bit 1
|
|
Mods = 2, ModRef = 3 // Mod = bit 2
|
|
};
|
|
unsigned AccessTy : 2;
|
|
|
|
/// AliasType - Keep track the relationships between the pointers in the set.
|
|
/// Lattice goes from MustAlias to MayAlias.
|
|
///
|
|
enum AliasType {
|
|
MustAlias = 0, MayAlias = 1
|
|
};
|
|
unsigned AliasTy : 1;
|
|
|
|
// Volatile - True if this alias set contains volatile loads or stores.
|
|
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:
|
|
/// Accessors...
|
|
bool isRef() const { return AccessTy & Refs; }
|
|
bool isMod() const { return AccessTy & Mods; }
|
|
bool isMustAlias() const { return AliasTy == MustAlias; }
|
|
bool isMayAlias() const { return AliasTy == MayAlias; }
|
|
|
|
// isVolatile - Return true if this alias set contains volatile loads or
|
|
// stores.
|
|
bool isVolatile() const { return Volatile; }
|
|
|
|
/// isForwardingAliasSet - Return true if this alias set should be ignored as
|
|
/// part of the AliasSetTracker object.
|
|
bool isForwardingAliasSet() const { return Forward; }
|
|
|
|
/// mergeSetIn - Merge the specified alias set into this alias set...
|
|
///
|
|
void mergeSetIn(AliasSet &AS, AliasSetTracker &AST);
|
|
|
|
// Alias Set iteration - Allow access to all of the pointer which are part of
|
|
// this alias set...
|
|
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;
|
|
|
|
/// Define an iterator for alias sets... this is just a forward iterator.
|
|
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); }
|
|
|
|
const iterator &operator=(const iterator &I) {
|
|
CurNode = I.CurNode;
|
|
return *this;
|
|
}
|
|
|
|
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(); }
|
|
const MDNode *getTBAAInfo() const { return CurNode->getTBAAInfo(); }
|
|
|
|
iterator& operator++() { // Preincrement
|
|
assert(CurNode && "Advancing past AliasSet.end()!");
|
|
CurNode = CurNode->getNext();
|
|
return *this;
|
|
}
|
|
iterator operator++(int) { // Postincrement
|
|
iterator tmp = *this; ++*this; return tmp;
|
|
}
|
|
};
|
|
|
|
private:
|
|
// Can only be created by AliasSetTracker. Also, ilist creates one
|
|
// to serve as a sentinel.
|
|
friend struct ilist_sentinel_traits<AliasSet>;
|
|
AliasSet()
|
|
: PtrList(nullptr), PtrListEnd(&PtrList), Forward(nullptr), RefCount(0),
|
|
AccessTy(NoModRef), AliasTy(MustAlias), Volatile(false) {
|
|
}
|
|
|
|
AliasSet(const AliasSet &AS) LLVM_DELETED_FUNCTION;
|
|
void operator=(const AliasSet &AS) LLVM_DELETED_FUNCTION;
|
|
|
|
PointerRec *getSomePointer() const {
|
|
return PtrList;
|
|
}
|
|
|
|
/// getForwardedTarget - Return the real alias set this represents. If this
|
|
/// has been merged with another set and is forwarding, return the ultimate
|
|
/// destination set. This also implements the union-find collapsing as well.
|
|
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 MDNode *TBAAInfo,
|
|
bool KnownMustAlias = false);
|
|
void addUnknownInst(Instruction *I, AliasAnalysis &AA);
|
|
void removeUnknownInst(Instruction *I) {
|
|
for (size_t i = 0, e = UnknownInsts.size(); i != e; ++i)
|
|
if (UnknownInsts[i] == I) {
|
|
UnknownInsts[i] = UnknownInsts.back();
|
|
UnknownInsts.pop_back();
|
|
--i; --e; // Revisit the moved entry.
|
|
}
|
|
}
|
|
void setVolatile() { Volatile = true; }
|
|
|
|
public:
|
|
/// aliasesPointer - Return true if the specified pointer "may" (or must)
|
|
/// alias one of the members in the set.
|
|
///
|
|
bool aliasesPointer(const Value *Ptr, uint64_t Size, const MDNode *TBAAInfo,
|
|
AliasAnalysis &AA) const;
|
|
bool aliasesUnknownInst(Instruction *Inst, AliasAnalysis &AA) const;
|
|
};
|
|
|
|
inline raw_ostream& operator<<(raw_ostream &OS, const AliasSet &AS) {
|
|
AS.print(OS);
|
|
return OS;
|
|
}
|
|
|
|
|
|
class AliasSetTracker {
|
|
/// CallbackVH - A CallbackVH to arrange for AliasSetTracker to be
|
|
/// notified whenever a Value is deleted.
|
|
class ASTCallbackVH : public CallbackVH {
|
|
AliasSetTracker *AST;
|
|
void deleted() override;
|
|
void allUsesReplacedWith(Value *) override;
|
|
public:
|
|
ASTCallbackVH(Value *V, AliasSetTracker *AST = nullptr);
|
|
ASTCallbackVH &operator=(Value *V);
|
|
};
|
|
/// ASTCallbackVHDenseMapInfo - Traits to tell DenseMap that tell us how to
|
|
/// compare and hash the value handle.
|
|
struct ASTCallbackVHDenseMapInfo : public DenseMapInfo<Value *> {};
|
|
|
|
AliasAnalysis &AA;
|
|
ilist<AliasSet> AliasSets;
|
|
|
|
typedef DenseMap<ASTCallbackVH, AliasSet::PointerRec*,
|
|
ASTCallbackVHDenseMapInfo>
|
|
PointerMapType;
|
|
|
|
// Map from pointers to their node
|
|
PointerMapType PointerMap;
|
|
|
|
public:
|
|
/// AliasSetTracker ctor - Create an empty collection of AliasSets, and use
|
|
/// the specified alias analysis object to disambiguate load and store
|
|
/// addresses.
|
|
explicit AliasSetTracker(AliasAnalysis &aa) : AA(aa) {}
|
|
~AliasSetTracker() { clear(); }
|
|
|
|
/// add methods - These methods are used to add different types of
|
|
/// instructions to the alias sets. Adding a new instruction can result in
|
|
/// one of three actions happening:
|
|
///
|
|
/// 1. If the instruction doesn't alias any other sets, create a new set.
|
|
/// 2. If the instruction aliases exactly one set, add it to the set
|
|
/// 3. If the instruction aliases multiple sets, merge the sets, and add
|
|
/// the instruction to the result.
|
|
///
|
|
/// These methods return true if inserting the instruction resulted in the
|
|
/// addition of a new alias set (i.e., the pointer did not alias anything).
|
|
///
|
|
bool add(Value *Ptr, uint64_t Size, const MDNode *TBAAInfo); // Add a location
|
|
bool add(LoadInst *LI);
|
|
bool add(StoreInst *SI);
|
|
bool add(VAArgInst *VAAI);
|
|
bool add(Instruction *I); // Dispatch to one of the other add methods...
|
|
void add(BasicBlock &BB); // Add all instructions in basic block
|
|
void add(const AliasSetTracker &AST); // Add alias relations from another AST
|
|
bool addUnknown(Instruction *I);
|
|
|
|
/// remove methods - These methods are used to remove all entries that might
|
|
/// be aliased by the specified instruction. These methods return true if any
|
|
/// alias sets were eliminated.
|
|
// Remove a location
|
|
bool remove(Value *Ptr, uint64_t Size, const MDNode *TBAAInfo);
|
|
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();
|
|
|
|
/// getAliasSets - Return the alias sets that are active.
|
|
///
|
|
const ilist<AliasSet> &getAliasSets() const { return AliasSets; }
|
|
|
|
/// getAliasSetForPointer - Return the alias set that the specified pointer
|
|
/// lives in. If the New argument is non-null, this method sets the value to
|
|
/// true if a new alias set is created to contain the pointer (because the
|
|
/// pointer didn't alias anything).
|
|
AliasSet &getAliasSetForPointer(Value *P, uint64_t Size,
|
|
const MDNode *TBAAInfo,
|
|
bool *New = nullptr);
|
|
|
|
/// getAliasSetForPointerIfExists - Return the alias set containing the
|
|
/// location specified if one exists, otherwise return null.
|
|
AliasSet *getAliasSetForPointerIfExists(Value *P, uint64_t Size,
|
|
const MDNode *TBAAInfo) {
|
|
return findAliasSetForPointer(P, Size, TBAAInfo);
|
|
}
|
|
|
|
/// containsPointer - Return true if the specified location is represented by
|
|
/// this alias set, false otherwise. This does not modify the AST object or
|
|
/// alias sets.
|
|
bool containsPointer(Value *P, uint64_t Size, const MDNode *TBAAInfo) const;
|
|
|
|
/// getAliasAnalysis - Return the underlying alias analysis object used by
|
|
/// this tracker.
|
|
AliasAnalysis &getAliasAnalysis() const { return AA; }
|
|
|
|
/// deleteValue method - This method is used to remove a pointer value from
|
|
/// the AliasSetTracker entirely. It should be used when an instruction is
|
|
/// deleted from the program to update the AST. If you don't use this, you
|
|
/// would have dangling pointers to deleted instructions.
|
|
///
|
|
void deleteValue(Value *PtrVal);
|
|
|
|
/// copyValue - This method should be used whenever a preexisting value in the
|
|
/// program is copied or cloned, introducing a new value. Note that it is ok
|
|
/// for clients that use this method to introduce the same value multiple
|
|
/// times: if the tracker already knows about a value, it will ignore the
|
|
/// request.
|
|
///
|
|
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);
|
|
|
|
// getEntryFor - Just like operator[] on the map, except that it creates an
|
|
// entry for the pointer if it doesn't already exist.
|
|
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 MDNode *TBAAInfo,
|
|
AliasSet::AccessType E,
|
|
bool &NewSet) {
|
|
NewSet = false;
|
|
AliasSet &AS = getAliasSetForPointer(P, Size, TBAAInfo, &NewSet);
|
|
AS.AccessTy |= E;
|
|
return AS;
|
|
}
|
|
AliasSet *findAliasSetForPointer(const Value *Ptr, uint64_t Size,
|
|
const MDNode *TBAAInfo);
|
|
|
|
AliasSet *findAliasSetForUnknownInst(Instruction *Inst);
|
|
};
|
|
|
|
inline raw_ostream& operator<<(raw_ostream &OS, const AliasSetTracker &AST) {
|
|
AST.print(OS);
|
|
return OS;
|
|
}
|
|
|
|
} // End llvm namespace
|
|
|
|
#endif
|