diff options
Diffstat (limited to 'include/llvm/Analysis/MemoryDependenceAnalysis.h')
| -rw-r--r-- | include/llvm/Analysis/MemoryDependenceAnalysis.h | 95 |
1 files changed, 49 insertions, 46 deletions
diff --git a/include/llvm/Analysis/MemoryDependenceAnalysis.h b/include/llvm/Analysis/MemoryDependenceAnalysis.h index a715eaeee11c..47afd1b77b0e 100644 --- a/include/llvm/Analysis/MemoryDependenceAnalysis.h +++ b/include/llvm/Analysis/MemoryDependenceAnalysis.h @@ -11,17 +11,17 @@ // //===----------------------------------------------------------------------===// -#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/Pass.h" +#include "llvm/Support/ValueHandle.h" namespace llvm { class Function; @@ -34,14 +34,14 @@ namespace llvm { 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, @@ -72,7 +72,7 @@ namespace llvm { /// 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*) @@ -99,7 +99,7 @@ namespace llvm { explicit MemDepResult(PairTy V) : Value(V) {} public: MemDepResult() : Value(0, Invalid) {} - + /// get methods: These are static ctor methods for creating various /// MemDepResult kinds. static MemDepResult getDef(Instruction *Inst) { @@ -130,7 +130,7 @@ namespace llvm { /// isDef - Return true if this MemDepResult represents a query that is /// 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. @@ -145,7 +145,7 @@ namespace llvm { 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 { @@ -159,7 +159,7 @@ namespace llvm { if (Value.getInt() == Other) return NULL; 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; } @@ -175,11 +175,11 @@ namespace llvm { /// 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)); } @@ -199,16 +199,16 @@ namespace llvm { // 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. @@ -218,17 +218,17 @@ namespace llvm { 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 @@ -238,7 +238,7 @@ namespace llvm { /// 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, @@ -297,30 +297,30 @@ namespace llvm { 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; DataLayout *TD; @@ -333,15 +333,15 @@ namespace llvm { /// Pass Implementation stuff. This doesn't do any analysis eagerly. bool runOnFunction(Function &); - + /// Clean up memory in between runs void releaseMemory(); - + /// getAnalysisUsage - Does not modify anything. It uses Value Numbering /// and Alias Analysis. /// virtual void getAnalysisUsage(AnalysisUsage &AU) const; - + /// 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. @@ -360,8 +360,8 @@ namespace llvm { /// 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. @@ -374,7 +374,7 @@ namespace llvm { /// 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 @@ -387,20 +387,23 @@ namespace llvm { /// This needs to be done when the CFG changes, e.g., due to splitting /// critical edges. void invalidateCachedPredecessors(); - + /// 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. + /// 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 AliasAnalysis::Location &Loc, - bool isLoad, + bool isLoad, BasicBlock::iterator ScanIt, - BasicBlock *BB); - - + BasicBlock *BB, + Instruction *QueryInst = 0); + + /// 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 @@ -413,7 +416,7 @@ namespace llvm { unsigned MemLocSize, const LoadInst *LI, const DataLayout &TD); - + private: MemDepResult getCallSiteDependencyFrom(CallSite C, bool isReadOnlyCall, BasicBlock::iterator ScanIt, @@ -430,11 +433,11 @@ namespace llvm { 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 |