AA metadata refactoring (introduce AAMDNodes)

In order to enable the preservation of noalias function parameter information
after inlining, and the representation of block-level __restrict__ pointer
information (etc.), additional kinds of aliasing metadata will be introduced.
This metadata needs to be carried around in AliasAnalysis::Location objects
(and MMOs at the SDAG level), and so we need to generalize the current scheme
(which is hard-coded to just one TBAA MDNode*).

This commit introduces only the necessary refactoring to allow for the
introduction of other aliasing metadata types, but does not actually introduce
any (that will come in a follow-up commit). What it does introduce is a new
AAMDNodes structure to hold all of the aliasing metadata nodes associated with
a particular memory-accessing instruction, and uses that structure instead of
the raw MDNode* in AliasAnalysis::Location, etc.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213859 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Hal Finkel
2014-07-24 12:16:19 +00:00
parent a4abc43a56
commit 2c7c54c86c
50 changed files with 521 additions and 389 deletions

View File

@ -20,6 +20,7 @@
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/ilist.h"
#include "llvm/ADT/ilist_node.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/ValueHandle.h"
#include <vector>
@ -40,11 +41,11 @@ class AliasSet : public ilist_node<AliasSet> {
PointerRec **PrevInList, *NextInList;
AliasSet *AS;
uint64_t Size;
const MDNode *TBAAInfo;
AAMDNodes AAInfo;
public:
PointerRec(Value *V)
: Val(V), PrevInList(nullptr), NextInList(nullptr), AS(nullptr), Size(0),
TBAAInfo(DenseMapInfo<const MDNode *>::getEmptyKey()) {}
AAInfo(DenseMapInfo<AAMDNodes>::getEmptyKey()) {}
Value *getValue() const { return Val; }
@ -56,27 +57,27 @@ class AliasSet : public ilist_node<AliasSet> {
return &NextInList;
}
void updateSizeAndTBAAInfo(uint64_t NewSize, const MDNode *NewTBAAInfo) {
void updateSizeAndAAInfo(uint64_t NewSize, const AAMDNodes &NewAAInfo) {
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();
if (AAInfo == DenseMapInfo<AAMDNodes>::getEmptyKey())
// We don't have a AAInfo yet. Set it to NewAAInfo.
AAInfo = NewAAInfo;
else if (AAInfo != NewAAInfo)
// NewAAInfo conflicts with AAInfo.
AAInfo = DenseMapInfo<AAMDNodes>::getTombstoneKey();
}
uint64_t getSize() const { return Size; }
/// getTBAAInfo - Return the TBAAInfo, or null if there is no
/// getAAInfo - Return the AAInfo, 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;
AAMDNodes getAAInfo() const {
// If we have missing or conflicting AAInfo, return null.
if (AAInfo == DenseMapInfo<AAMDNodes>::getEmptyKey() ||
AAInfo == DenseMapInfo<AAMDNodes>::getTombstoneKey())
return AAMDNodes();
return AAInfo;
}
AliasSet *getAliasSet(AliasSetTracker &AST) {
@ -204,7 +205,7 @@ public:
Value *getPointer() const { return CurNode->getValue(); }
uint64_t getSize() const { return CurNode->getSize(); }
const MDNode *getTBAAInfo() const { return CurNode->getTBAAInfo(); }
AAMDNodes getAAInfo() const { return CurNode->getAAInfo(); }
iterator& operator++() { // Preincrement
assert(CurNode && "Advancing past AliasSet.end()!");
@ -250,7 +251,7 @@ private:
void removeFromTracker(AliasSetTracker &AST);
void addPointer(AliasSetTracker &AST, PointerRec &Entry, uint64_t Size,
const MDNode *TBAAInfo,
const AAMDNodes &AAInfo,
bool KnownMustAlias = false);
void addUnknownInst(Instruction *I, AliasAnalysis &AA);
void removeUnknownInst(Instruction *I) {
@ -267,7 +268,7 @@ 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,
bool aliasesPointer(const Value *Ptr, uint64_t Size, const AAMDNodes &AAInfo,
AliasAnalysis &AA) const;
bool aliasesUnknownInst(Instruction *Inst, AliasAnalysis &AA) const;
};
@ -322,7 +323,7 @@ public:
/// 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(Value *Ptr, uint64_t Size, const AAMDNodes &AAInfo); // Add a loc.
bool add(LoadInst *LI);
bool add(StoreInst *SI);
bool add(VAArgInst *VAAI);
@ -335,7 +336,7 @@ public:
/// 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(Value *Ptr, uint64_t Size, const AAMDNodes &AAInfo);
bool remove(LoadInst *LI);
bool remove(StoreInst *SI);
bool remove(VAArgInst *VAAI);
@ -354,20 +355,20 @@ public:
/// 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,
const AAMDNodes &AAInfo,
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);
const AAMDNodes &AAInfo) {
return findAliasSetForPointer(P, Size, AAInfo);
}
/// 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;
bool containsPointer(Value *P, uint64_t Size, const AAMDNodes &AAInfo) const;
/// getAliasAnalysis - Return the underlying alias analysis object used by
/// this tracker.
@ -414,16 +415,16 @@ private:
return *Entry;
}
AliasSet &addPointer(Value *P, uint64_t Size, const MDNode *TBAAInfo,
AliasSet &addPointer(Value *P, uint64_t Size, const AAMDNodes &AAInfo,
AliasSet::AccessType E,
bool &NewSet) {
NewSet = false;
AliasSet &AS = getAliasSetForPointer(P, Size, TBAAInfo, &NewSet);
AliasSet &AS = getAliasSetForPointer(P, Size, AAInfo, &NewSet);
AS.AccessTy |= E;
return AS;
}
AliasSet *findAliasSetForPointer(const Value *Ptr, uint64_t Size,
const MDNode *TBAAInfo);
const AAMDNodes &AAInfo);
AliasSet *findAliasSetForUnknownInst(Instruction *Inst);
};