//
//===----------------------------------------------------------------------===//
-#ifndef LLVM_ANALYSIS_MEMORY_DEPENDENCE_H
-#define LLVM_ANALYSIS_MEMORY_DEPENDENCE_H
+#ifndef LLVM_ANALYSIS_MEMORYDEPENDENCEANALYSIS_H
+#define LLVM_ANALYSIS_MEMORYDEPENDENCEANALYSIS_H
-#include "llvm/BasicBlock.h"
-#include "llvm/Pass.h"
-#include "llvm/Support/ValueHandle.h"
-#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/PointerIntPair.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/PredIteratorCache.h"
+#include "llvm/IR/ValueHandle.h"
+#include "llvm/Pass.h"
namespace llvm {
class Function;
class Instruction;
class CallSite;
class AliasAnalysis;
- class TargetData;
+ class AssumptionCache;
class MemoryDependenceAnalysis;
class PredIteratorCache;
class DominatorTree;
class PHITransAddr;
-
+
/// MemDepResult - A memory dependence query can return one of three different
/// answers, described below.
class MemDepResult {
enum DepType {
/// Invalid - Clients of MemDep never see this.
Invalid = 0,
-
+
/// Clobber - This is a dependence on the specified instruction which
/// clobbers the desired value. The pointer member of the MemDepResult
/// pair holds the instruction that clobbers the memory. For example,
/// this occurs when we see a may-aliased store to the memory location we
/// care about.
+ ///
+ /// There are several cases that may be interesting here:
+ /// 1. Loads are clobbered by may-alias stores.
+ /// 2. Loads are considered clobbered by partially-aliased loads. The
+ /// client may choose to analyze deeper into these cases.
Clobber,
/// Def - This is a dependence on the specified instruction which
/// and no intervening clobbers. No validation is done that the
/// operands to the calls are the same.
Def,
-
+
+ /// Other - This marker indicates that the query has no known dependency
+ /// in the specified block. More detailed state info is encoded in the
+ /// upper part of the pair (i.e. the Instruction*)
+ Other
+ };
+ /// If DepType is "Other", the upper part of the pair
+ /// (i.e. the Instruction* part) is instead used to encode more detailed
+ /// type information as follows
+ enum OtherType {
/// NonLocal - This marker indicates that the query has no dependency in
/// the specified block. To find out more, the client should query other
/// predecessor blocks.
- NonLocal
+ NonLocal = 0x4,
+ /// NonFuncLocal - This marker indicates that the query has no
+ /// dependency in the specified function.
+ NonFuncLocal = 0x8,
+ /// Unknown - This marker indicates that the query dependency
+ /// is unknown.
+ Unknown = 0xc
};
+
typedef PointerIntPair<Instruction*, 2, DepType> PairTy;
PairTy Value;
explicit MemDepResult(PairTy V) : Value(V) {}
public:
- MemDepResult() : Value(0, Invalid) {}
-
+ MemDepResult() : Value(nullptr, Invalid) {}
+
/// get methods: These are static ctor methods for creating various
/// MemDepResult kinds.
static MemDepResult getDef(Instruction *Inst) {
+ assert(Inst && "Def requires inst");
return MemDepResult(PairTy(Inst, Def));
}
static MemDepResult getClobber(Instruction *Inst) {
+ assert(Inst && "Clobber requires inst");
return MemDepResult(PairTy(Inst, Clobber));
}
static MemDepResult getNonLocal() {
- return MemDepResult(PairTy(0, NonLocal));
+ return MemDepResult(
+ PairTy(reinterpret_cast<Instruction*>(NonLocal), Other));
+ }
+ static MemDepResult getNonFuncLocal() {
+ return MemDepResult(
+ PairTy(reinterpret_cast<Instruction*>(NonFuncLocal), Other));
+ }
+ static MemDepResult getUnknown() {
+ return MemDepResult(
+ PairTy(reinterpret_cast<Instruction*>(Unknown), Other));
}
/// isClobber - Return true if this MemDepResult represents a query that is
- /// a instruction clobber dependency.
+ /// an instruction clobber dependency.
bool isClobber() const { return Value.getInt() == Clobber; }
/// isDef - Return true if this MemDepResult represents a query that is
- /// a instruction definition dependency.
+ /// an instruction definition dependency.
bool isDef() const { return Value.getInt() == Def; }
-
+
/// isNonLocal - Return true if this MemDepResult represents a query that
/// is transparent to the start of the block, but where a non-local hasn't
/// been done.
- bool isNonLocal() const { return Value.getInt() == NonLocal; }
-
+ bool isNonLocal() const {
+ return Value.getInt() == Other
+ && Value.getPointer() == reinterpret_cast<Instruction*>(NonLocal);
+ }
+
+ /// isNonFuncLocal - Return true if this MemDepResult represents a query
+ /// that is transparent to the start of the function.
+ bool isNonFuncLocal() const {
+ return Value.getInt() == Other
+ && Value.getPointer() == reinterpret_cast<Instruction*>(NonFuncLocal);
+ }
+
+ /// isUnknown - Return true if this MemDepResult represents a query which
+ /// cannot and/or will not be computed.
+ bool isUnknown() const {
+ return Value.getInt() == Other
+ && Value.getPointer() == reinterpret_cast<Instruction*>(Unknown);
+ }
+
/// getInst() - If this is a normal dependency, return the instruction that
/// is depended on. Otherwise, return null.
- Instruction *getInst() const { return Value.getPointer(); }
-
+ Instruction *getInst() const {
+ if (Value.getInt() == Other) return nullptr;
+ return Value.getPointer();
+ }
+
bool operator==(const MemDepResult &M) const { return Value == M.Value; }
bool operator!=(const MemDepResult &M) const { return Value != M.Value; }
bool operator<(const MemDepResult &M) const { return Value < M.Value; }
/// In a default-constructed MemDepResult object, the type will be Dirty
/// and the instruction pointer will be null.
///
-
+
/// isDirty - Return true if this is a MemDepResult in its dirty/invalid.
/// state.
bool isDirty() const { return Value.getInt() == Invalid; }
-
+
static MemDepResult getDirty(Instruction *Inst) {
return MemDepResult(PairTy(Inst, Invalid));
}
// BB is the sort key, it can't be changed.
BasicBlock *getBB() const { return BB; }
-
+
void setResult(const MemDepResult &R) { Result = R; }
const MemDepResult &getResult() const { return Result; }
-
+
bool operator<(const NonLocalDepEntry &RHS) const {
return BB < RHS.BB;
}
};
-
+
/// NonLocalDepResult - This is a result from a NonLocal dependence query.
/// For each BasicBlock (the BB entry) it keeps a MemDepResult and the
/// (potentially phi translated) address that was live in the block.
public:
NonLocalDepResult(BasicBlock *bb, MemDepResult result, Value *address)
: Entry(bb, result), Address(address) {}
-
+
// BB is the sort key, it can't be changed.
BasicBlock *getBB() const { return Entry.getBB(); }
-
+
void setResult(const MemDepResult &R, Value *Addr) {
Entry.setResult(R);
Address = Addr;
}
-
+
const MemDepResult &getResult() const { return Entry.getResult(); }
-
+
/// getAddress - Return the address of this pointer in this block. This can
/// be different than the address queried for the non-local result because
/// of phi translation. This returns null if the address was not available
/// The address is always null for a non-local 'call' dependence.
Value *getAddress() const { return Address; }
};
-
+
/// MemoryDependenceAnalysis - This is an analysis that determines, for a
/// given memory operation, what preceding memory operations it depends on.
/// It builds on alias analysis information, and tries to provide a lazy,
/// Size - The maximum size of the dereferences of the
/// pointer. May be UnknownSize if the sizes are unknown.
uint64_t Size;
- /// TBAATag - The TBAA tag associated with dereferences of the
- /// pointer. May be null if there are no tags or conflicting tags.
- const MDNode *TBAATag;
+ /// AATags - The AA tags associated with dereferences of the
+ /// pointer. The members may be null if there are no tags or
+ /// conflicting tags.
+ AAMDNodes AATags;
- NonLocalPointerInfo() : Size(AliasAnalysis::UnknownSize), TBAATag(0) {}
+ NonLocalPointerInfo() : Size(MemoryLocation::UnknownSize) {}
};
/// CachedNonLocalPointerInfo - This map stores the cached results of doing
CachedNonLocalPointerInfo NonLocalPointerDeps;
// A map from instructions to their non-local pointer dependencies.
- typedef DenseMap<Instruction*,
+ typedef DenseMap<Instruction*,
SmallPtrSet<ValueIsLoadPair, 4> > ReverseNonLocalPtrDepTy;
ReverseNonLocalPtrDepTy ReverseNonLocalPtrDeps;
-
+
/// PerInstNLInfo - This is the instruction we keep for each cached access
/// that we have for an instruction. The pointer is an owning pointer and
/// the bool indicates whether we have any dirty bits in the set.
typedef std::pair<NonLocalDepInfo, bool> PerInstNLInfo;
-
+
// A map from instructions to their non-local dependencies.
typedef DenseMap<Instruction*, PerInstNLInfo> NonLocalDepMapType;
-
+
NonLocalDepMapType NonLocalDeps;
-
+
// A reverse mapping from dependencies to the dependees. This is
// used when removing instructions to keep the cache coherent.
typedef DenseMap<Instruction*,
SmallPtrSet<Instruction*, 4> > ReverseDepMapType;
ReverseDepMapType ReverseLocalDeps;
-
+
// A reverse mapping from dependencies to the non-local dependees.
ReverseDepMapType ReverseNonLocalDeps;
-
+
/// Current AA implementation, just a cache.
AliasAnalysis *AA;
- TargetData *TD;
- OwningPtr<PredIteratorCache> PredCache;
+ DominatorTree *DT;
+ AssumptionCache *AC;
+ const TargetLibraryInfo *TLI;
+ PredIteratorCache PredCache;
+
public:
MemoryDependenceAnalysis();
- ~MemoryDependenceAnalysis();
+ ~MemoryDependenceAnalysis() override;
static char ID;
/// Pass Implementation stuff. This doesn't do any analysis eagerly.
- bool runOnFunction(Function &);
-
+ bool runOnFunction(Function &) override;
+
/// Clean up memory in between runs
- void releaseMemory();
-
+ void releaseMemory() override;
+
/// getAnalysisUsage - Does not modify anything. It uses Value Numbering
/// and Alias Analysis.
///
- virtual void getAnalysisUsage(AnalysisUsage &AU) const;
-
+ void getAnalysisUsage(AnalysisUsage &AU) const override;
+
/// getDependency - Return the instruction on which a memory operation
/// depends. See the class comment for more details. It is illegal to call
/// this on non-memory instructions.
/// removed. Clients must copy this data if they want it around longer than
/// that.
const NonLocalDepInfo &getNonLocalCallDependency(CallSite QueryCS);
-
-
+
+
/// getNonLocalPointerDependency - Perform a full dependency query for an
- /// access to the specified (non-volatile) memory location, returning the
- /// set of instructions that either define or clobber the value.
+ /// access to the QueryInst's specified memory location, returning the set
+ /// of instructions that either define or clobber the value.
+ ///
+ /// Warning: For a volatile query instruction, the dependencies will be
+ /// accurate, and thus usable for reordering, but it is never legal to
+ /// remove the query instruction.
///
- /// This method assumes the pointer has a "NonLocal" dependency within BB.
- void getNonLocalPointerDependency(const AliasAnalysis::Location &Loc,
- bool isLoad, BasicBlock *BB,
+ /// This method assumes the pointer has a "NonLocal" dependency within
+ /// QueryInst's parent basic block.
+ void getNonLocalPointerDependency(Instruction *QueryInst,
SmallVectorImpl<NonLocalDepResult> &Result);
/// removeInstruction - Remove an instruction from the dependence analysis,
/// updating the dependence of instructions that previously depended on it.
void removeInstruction(Instruction *InstToRemove);
-
+
/// invalidateCachedPointerInfo - This method is used to invalidate cached
/// information about the specified pointer, because it may be too
/// conservative in memdep. This is an optional call that can be used when
/// This needs to be done when the CFG changes, e.g., due to splitting
/// critical edges.
void invalidateCachedPredecessors();
-
- private:
- MemDepResult getPointerDependencyFrom(const AliasAnalysis::Location &Loc,
- bool isLoad,
+
+ /// getPointerDependencyFrom - Return the instruction on which a memory
+ /// location depends. If isLoad is true, this routine ignores may-aliases
+ /// with read-only operations. If isLoad is false, this routine ignores
+ /// may-aliases with reads from read-only locations. If possible, pass
+ /// the query instruction as well; this function may take advantage of
+ /// the metadata annotated to the query instruction to refine the result.
+ ///
+ /// Note that this is an uncached query, and thus may be inefficient.
+ ///
+ MemDepResult getPointerDependencyFrom(const MemoryLocation &Loc,
+ bool isLoad,
BasicBlock::iterator ScanIt,
- BasicBlock *BB);
+ BasicBlock *BB,
+ Instruction *QueryInst = nullptr);
+
+ /// getLoadLoadClobberFullWidthSize - This is a little bit of analysis that
+ /// looks at a memory location for a load (specified by MemLocBase, Offs,
+ /// and Size) and compares it against a load. If the specified load could
+ /// be safely widened to a larger integer load that is 1) still efficient,
+ /// 2) safe for the target, and 3) would provide the specified memory
+ /// location value, then this function returns the size in bytes of the
+ /// load width to use. If not, this returns zero.
+ static unsigned getLoadLoadClobberFullWidthSize(const Value *MemLocBase,
+ int64_t MemLocOffs,
+ unsigned MemLocSize,
+ const LoadInst *LI);
+
+ private:
MemDepResult getCallSiteDependencyFrom(CallSite C, bool isReadOnlyCall,
BasicBlock::iterator ScanIt,
BasicBlock *BB);
- bool getNonLocalPointerDepFromBB(const PHITransAddr &Pointer,
- const AliasAnalysis::Location &Loc,
- bool isLoad, BasicBlock *BB,
+ bool getNonLocalPointerDepFromBB(Instruction *QueryInst,
+ const PHITransAddr &Pointer,
+ const MemoryLocation &Loc, bool isLoad,
+ BasicBlock *BB,
SmallVectorImpl<NonLocalDepResult> &Result,
- DenseMap<BasicBlock*, Value*> &Visited,
+ DenseMap<BasicBlock *, Value *> &Visited,
bool SkipFirstBlock = false);
- MemDepResult GetNonLocalInfoForBlock(const AliasAnalysis::Location &Loc,
- bool isLoad, BasicBlock *BB,
- NonLocalDepInfo *Cache,
+ MemDepResult GetNonLocalInfoForBlock(Instruction *QueryInst,
+ const MemoryLocation &Loc, bool isLoad,
+ BasicBlock *BB, NonLocalDepInfo *Cache,
unsigned NumSortedEntries);
void RemoveCachedNonLocalPointerDependencies(ValueIsLoadPair P);
-
+
/// verifyRemoved - Verify that the specified instruction does not occur
/// in our internal data structures.
void verifyRemoved(Instruction *Inst) const;
-
+
};
} // End llvm namespace
projects / oota-llvm.git / blobdiff