From: Chandler Carruth <chandlerc@gmail.com>
Date: Thu, 4 Jun 2015 02:03:15 +0000 (+0000)
Subject: [PM/AA] Start refactoring AliasAnalysis to remove the analysis group and
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=dc967a97df7d1acc035939c149c856563e64e292;p=oota-llvm.git

[PM/AA] Start refactoring AliasAnalysis to remove the analysis group and
port it to the new pass manager.

All this does is extract the inner "location" class used by AA into its
own full fledged type. This seems *much* cleaner as MemoryDependence and
soon MemorySSA also use this heavily, and it doesn't make much sense
being inside the AA infrastructure.

This will also make it much easier to break apart the AA infrastructure
into something that stands on its own rather than using the analysis
group design.

There are a few places where this makes APIs not make sense -- they were
taking an AliasAnalysis pointer just to build locations. I'll try to
clean those up in follow-up commits.

Differential Revision: http://reviews.llvm.org/D10228

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@239003 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/llvm/Analysis/AliasAnalysis.h b/include/llvm/Analysis/AliasAnalysis.h
index ac9d21c590a..de18e585f11 100644
--- a/include/llvm/Analysis/AliasAnalysis.h
+++ b/include/llvm/Analysis/AliasAnalysis.h
@@ -40,6 +40,7 @@
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/IR/CallSite.h"
 #include "llvm/IR/Metadata.h"
+#include "llvm/Analysis/MemoryLocation.h"
 
 namespace llvm {
 
@@ -82,7 +83,7 @@ public:
   /// UnknownSize - This is a special value which can be used with the
   /// size arguments in alias queries to indicate that the caller does not
   /// know the sizes of the potential memory references.
-  static uint64_t const UnknownSize = ~UINT64_C(0);
+  static uint64_t const UnknownSize = MemoryLocation::UnknownSize;
 
   /// getTargetLibraryInfo - Return a pointer to the current TargetLibraryInfo
   /// object, or null if no TargetLibraryInfo object is available.
@@ -98,70 +99,9 @@ public:
   /// Alias Queries...
   ///
 
-  /// Location - A description of a memory location.
-  struct Location {
-    /// Ptr - The address of the start of the location.
-    const Value *Ptr;
-    /// Size - The maximum size of the location, in address-units, or
-    /// UnknownSize if the size is not known.  Note that an unknown size does
-    /// not mean the pointer aliases the entire virtual address space, because
-    /// there are restrictions on stepping out of one object and into another.
-    /// See http://llvm.org/docs/LangRef.html#pointeraliasing
-    uint64_t Size;
-    /// AATags - The metadata nodes which describes the aliasing of the
-    /// location (each member is null if that kind of information is
-    /// unavailable)..
-    AAMDNodes AATags;
-
-    explicit Location(const Value *P = nullptr, uint64_t S = UnknownSize,
-                      const AAMDNodes &N = AAMDNodes())
-      : Ptr(P), Size(S), AATags(N) {}
-
-    Location getWithNewPtr(const Value *NewPtr) const {
-      Location Copy(*this);
-      Copy.Ptr = NewPtr;
-      return Copy;
-    }
-
-    Location getWithNewSize(uint64_t NewSize) const {
-      Location Copy(*this);
-      Copy.Size = NewSize;
-      return Copy;
-    }
-
-    Location getWithoutAATags() const {
-      Location Copy(*this);
-      Copy.AATags = AAMDNodes();
-      return Copy;
-    }
-
-    bool operator==(const AliasAnalysis::Location &Other) const {
-      return Ptr == Other.Ptr && Size == Other.Size && AATags == Other.AATags;
-    }
-  };
-
-  /// getLocation - Fill in Loc with information about the memory reference by
-  /// the given instruction.
-  Location getLocation(const LoadInst *LI);
-  Location getLocation(const StoreInst *SI);
-  Location getLocation(const VAArgInst *VI);
-  Location getLocation(const AtomicCmpXchgInst *CXI);
-  Location getLocation(const AtomicRMWInst *RMWI);
-  static Location getLocationForSource(const MemTransferInst *MTI);
-  static Location getLocationForDest(const MemIntrinsic *MI);
-  Location getLocation(const Instruction *Inst) {
-    if (auto *I = dyn_cast<LoadInst>(Inst))
-      return getLocation(I);
-    else if (auto *I = dyn_cast<StoreInst>(Inst))
-      return getLocation(I);
-    else if (auto *I = dyn_cast<VAArgInst>(Inst))
-      return getLocation(I);
-    else if (auto *I = dyn_cast<AtomicCmpXchgInst>(Inst))
-      return getLocation(I);
-    else if (auto *I = dyn_cast<AtomicRMWInst>(Inst))
-      return getLocation(I);
-    llvm_unreachable("unsupported memory instruction");
-  }
+  /// Legacy typedef for the AA location object. New code should use \c
+  /// MemoryLocation directly.
+  typedef MemoryLocation Location;
 
   /// Alias analysis result - Either we know for sure that it does not alias, we
   /// know for sure it must alias, or we don't know anything: The two pointers
@@ -601,28 +541,6 @@ public:
   }
 };
 
-// Specialize DenseMapInfo for Location.
-template<>
-struct DenseMapInfo<AliasAnalysis::Location> {
-  static inline AliasAnalysis::Location getEmptyKey() {
-    return AliasAnalysis::Location(DenseMapInfo<const Value *>::getEmptyKey(),
-                                   0);
-  }
-  static inline AliasAnalysis::Location getTombstoneKey() {
-    return AliasAnalysis::Location(
-        DenseMapInfo<const Value *>::getTombstoneKey(), 0);
-  }
-  static unsigned getHashValue(const AliasAnalysis::Location &Val) {
-    return DenseMapInfo<const Value *>::getHashValue(Val.Ptr) ^
-           DenseMapInfo<uint64_t>::getHashValue(Val.Size) ^
-           DenseMapInfo<AAMDNodes>::getHashValue(Val.AATags);
-  }
-  static bool isEqual(const AliasAnalysis::Location &LHS,
-                      const AliasAnalysis::Location &RHS) {
-    return LHS == RHS;
-  }
-};
-
 /// isNoAliasCall - Return true if this pointer is returned by a noalias
 /// function.
 bool isNoAliasCall(const Value *V);
diff --git a/include/llvm/Analysis/MemoryLocation.h b/include/llvm/Analysis/MemoryLocation.h
new file mode 100644
index 00000000000..94d938dc491
--- /dev/null
+++ b/include/llvm/Analysis/MemoryLocation.h
@@ -0,0 +1,137 @@
+//===- MemoryLocation.h - Memory location descriptions ----------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// This file provides utility analysis objects describing memory locations.
+/// These are used both by the Alias Analysis infrastructure and more
+/// specialized memory analysis layers.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_MEMORYLOCATION_H
+#define LLVM_ANALYSIS_MEMORYLOCATION_H
+
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/IR/CallSite.h"
+#include "llvm/IR/Metadata.h"
+
+namespace llvm {
+
+class LoadInst;
+class StoreInst;
+class MemTransferInst;
+class MemIntrinsic;
+
+/// Representation for a specific memory location.
+///
+/// This abstraction can be used to represent a specific location in memory.
+/// The goal of the location is to represent enough information to describe
+/// abstract aliasing, modification, and reference behaviors of whatever
+/// value(s) are stored in memory at the particular location.
+///
+/// The primary user of this interface is LLVM's Alias Analysis, but other
+/// memory analyses such as MemoryDependence can use it as well.
+class MemoryLocation {
+public:
+  /// UnknownSize - This is a special value which can be used with the
+  /// size arguments in alias queries to indicate that the caller does not
+  /// know the sizes of the potential memory references.
+  enum : uint64_t { UnknownSize = ~UINT64_C(0) };
+
+  /// The address of the start of the location.
+  const Value *Ptr;
+
+  /// The maximum size of the location, in address-units, or
+  /// UnknownSize if the size is not known.
+  ///
+  /// Note that an unknown size does not mean the pointer aliases the entire
+  /// virtual address space, because there are restrictions on stepping out of
+  /// one object and into another. See
+  /// http://llvm.org/docs/LangRef.html#pointeraliasing
+  uint64_t Size;
+
+  /// The metadata nodes which describes the aliasing of the location (each
+  /// member is null if that kind of information is unavailable).
+  AAMDNodes AATags;
+
+  /// Return a location with information about the memory reference by the given
+  /// instruction.
+  static MemoryLocation get(const LoadInst *LI);
+  static MemoryLocation get(const StoreInst *SI);
+  static MemoryLocation get(const VAArgInst *VI);
+  static MemoryLocation get(const AtomicCmpXchgInst *CXI);
+  static MemoryLocation get(const AtomicRMWInst *RMWI);
+  static MemoryLocation get(const Instruction *Inst) {
+    if (auto *I = dyn_cast<LoadInst>(Inst))
+      return get(I);
+    else if (auto *I = dyn_cast<StoreInst>(Inst))
+      return get(I);
+    else if (auto *I = dyn_cast<VAArgInst>(Inst))
+      return get(I);
+    else if (auto *I = dyn_cast<AtomicCmpXchgInst>(Inst))
+      return get(I);
+    else if (auto *I = dyn_cast<AtomicRMWInst>(Inst))
+      return get(I);
+    llvm_unreachable("unsupported memory instruction");
+  }
+
+  /// Return a location representing the source of a memory transfer.
+  static MemoryLocation getForSource(const MemTransferInst *MTI);
+
+  /// Return a location representing the destination of a memory set or
+  /// transfer.
+  static MemoryLocation getForDest(const MemIntrinsic *MI);
+
+  explicit MemoryLocation(const Value *Ptr = nullptr,
+                          uint64_t Size = UnknownSize,
+                          const AAMDNodes &AATags = AAMDNodes())
+      : Ptr(Ptr), Size(Size), AATags(AATags) {}
+
+  MemoryLocation getWithNewPtr(const Value *NewPtr) const {
+    MemoryLocation Copy(*this);
+    Copy.Ptr = NewPtr;
+    return Copy;
+  }
+
+  MemoryLocation getWithNewSize(uint64_t NewSize) const {
+    MemoryLocation Copy(*this);
+    Copy.Size = NewSize;
+    return Copy;
+  }
+
+  MemoryLocation getWithoutAATags() const {
+    MemoryLocation Copy(*this);
+    Copy.AATags = AAMDNodes();
+    return Copy;
+  }
+
+  bool operator==(const MemoryLocation &Other) const {
+    return Ptr == Other.Ptr && Size == Other.Size && AATags == Other.AATags;
+  }
+};
+
+// Specialize DenseMapInfo for MemoryLocation.
+template <> struct DenseMapInfo<MemoryLocation> {
+  static inline MemoryLocation getEmptyKey() {
+    return MemoryLocation(DenseMapInfo<const Value *>::getEmptyKey(), 0);
+  }
+  static inline MemoryLocation getTombstoneKey() {
+    return MemoryLocation(DenseMapInfo<const Value *>::getTombstoneKey(), 0);
+  }
+  static unsigned getHashValue(const MemoryLocation &Val) {
+    return DenseMapInfo<const Value *>::getHashValue(Val.Ptr) ^
+           DenseMapInfo<uint64_t>::getHashValue(Val.Size) ^
+           DenseMapInfo<AAMDNodes>::getHashValue(Val.AATags);
+  }
+  static bool isEqual(const MemoryLocation &LHS, const MemoryLocation &RHS) {
+    return LHS == RHS;
+  }
+};
+}
+
+#endif
diff --git a/lib/Analysis/AliasAnalysis.cpp b/lib/Analysis/AliasAnalysis.cpp
index f54e234bbea..ce46d530051 100644
--- a/lib/Analysis/AliasAnalysis.cpp
+++ b/lib/Analysis/AliasAnalysis.cpp
@@ -93,7 +93,7 @@ AliasAnalysis::getModRefInfo(Instruction *I, ImmutableCallSite Call) {
     // location this memory access defines.  The best we can say
     // is that if the call references what this instruction
     // defines, it must be clobbered by this location.
-    const AliasAnalysis::Location DefLoc = AA->getLocation(I);
+    const AliasAnalysis::Location DefLoc = MemoryLocation::get(I);
     if (getModRefInfo(Call, DefLoc) != AliasAnalysis::NoModRef)
       return AliasAnalysis::ModRef;
   }
@@ -267,78 +267,6 @@ AliasAnalysis::getModRefBehavior(const Function *F) {
 // AliasAnalysis non-virtual helper method implementation
 //===----------------------------------------------------------------------===//
 
-AliasAnalysis::Location AliasAnalysis::getLocation(const LoadInst *LI) {
-  AAMDNodes AATags;
-  LI->getAAMetadata(AATags);
-
-  return Location(LI->getPointerOperand(),
-                  getTypeStoreSize(LI->getType()), AATags);
-}
-
-AliasAnalysis::Location AliasAnalysis::getLocation(const StoreInst *SI) {
-  AAMDNodes AATags;
-  SI->getAAMetadata(AATags);
-
-  return Location(SI->getPointerOperand(),
-                  getTypeStoreSize(SI->getValueOperand()->getType()), AATags);
-}
-
-AliasAnalysis::Location AliasAnalysis::getLocation(const VAArgInst *VI) {
-  AAMDNodes AATags;
-  VI->getAAMetadata(AATags);
-
-  return Location(VI->getPointerOperand(), UnknownSize, AATags);
-}
-
-AliasAnalysis::Location
-AliasAnalysis::getLocation(const AtomicCmpXchgInst *CXI) {
-  AAMDNodes AATags;
-  CXI->getAAMetadata(AATags);
-
-  return Location(CXI->getPointerOperand(),
-                  getTypeStoreSize(CXI->getCompareOperand()->getType()),
-                  AATags);
-}
-
-AliasAnalysis::Location
-AliasAnalysis::getLocation(const AtomicRMWInst *RMWI) {
-  AAMDNodes AATags;
-  RMWI->getAAMetadata(AATags);
-
-  return Location(RMWI->getPointerOperand(),
-                  getTypeStoreSize(RMWI->getValOperand()->getType()), AATags);
-}
-
-AliasAnalysis::Location
-AliasAnalysis::getLocationForSource(const MemTransferInst *MTI) {
-  uint64_t Size = UnknownSize;
-  if (ConstantInt *C = dyn_cast<ConstantInt>(MTI->getLength()))
-    Size = C->getValue().getZExtValue();
-
-  // memcpy/memmove can have AA tags. For memcpy, they apply
-  // to both the source and the destination.
-  AAMDNodes AATags;
-  MTI->getAAMetadata(AATags);
-
-  return Location(MTI->getRawSource(), Size, AATags);
-}
-
-AliasAnalysis::Location
-AliasAnalysis::getLocationForDest(const MemIntrinsic *MTI) {
-  uint64_t Size = UnknownSize;
-  if (ConstantInt *C = dyn_cast<ConstantInt>(MTI->getLength()))
-    Size = C->getValue().getZExtValue();
-
-  // memcpy/memmove can have AA tags. For memcpy, they apply
-  // to both the source and the destination.
-  AAMDNodes AATags;
-  MTI->getAAMetadata(AATags);
-
-  return Location(MTI->getRawDest(), Size, AATags);
-}
-
-
-
 AliasAnalysis::ModRefResult
 AliasAnalysis::getModRefInfo(const LoadInst *L, const Location &Loc) {
   // Be conservative in the face of volatile/atomic.
@@ -347,7 +275,7 @@ AliasAnalysis::getModRefInfo(const LoadInst *L, const Location &Loc) {
 
   // If the load address doesn't alias the given address, it doesn't read
   // or write the specified memory.
-  if (Loc.Ptr && !alias(getLocation(L), Loc))
+  if (Loc.Ptr && !alias(MemoryLocation::get(L), Loc))
     return NoModRef;
 
   // Otherwise, a load just reads.
@@ -363,7 +291,7 @@ AliasAnalysis::getModRefInfo(const StoreInst *S, const Location &Loc) {
   if (Loc.Ptr) {
     // If the store address cannot alias the pointer in question, then the
     // specified memory cannot be modified by the store.
-    if (!alias(getLocation(S), Loc))
+    if (!alias(MemoryLocation::get(S), Loc))
       return NoModRef;
 
     // If the pointer is a pointer to constant memory, then it could not have
@@ -383,7 +311,7 @@ AliasAnalysis::getModRefInfo(const VAArgInst *V, const Location &Loc) {
   if (Loc.Ptr) {
     // If the va_arg address cannot alias the pointer in question, then the
     // specified memory cannot be accessed by the va_arg.
-    if (!alias(getLocation(V), Loc))
+    if (!alias(MemoryLocation::get(V), Loc))
       return NoModRef;
 
     // If the pointer is a pointer to constant memory, then it could not have
@@ -403,7 +331,7 @@ AliasAnalysis::getModRefInfo(const AtomicCmpXchgInst *CX, const Location &Loc) {
     return ModRef;
 
   // If the cmpxchg address does not alias the location, it does not access it.
-  if (Loc.Ptr && !alias(getLocation(CX), Loc))
+  if (Loc.Ptr && !alias(MemoryLocation::get(CX), Loc))
     return NoModRef;
 
   return ModRef;
@@ -416,7 +344,7 @@ AliasAnalysis::getModRefInfo(const AtomicRMWInst *RMW, const Location &Loc) {
     return ModRef;
 
   // If the atomicrmw address does not alias the location, it does not access it.
-  if (Loc.Ptr && !alias(getLocation(RMW), Loc))
+  if (Loc.Ptr && !alias(MemoryLocation::get(RMW), Loc))
     return NoModRef;
 
   return ModRef;
diff --git a/lib/Analysis/AliasAnalysisEvaluator.cpp b/lib/Analysis/AliasAnalysisEvaluator.cpp
index 273eacc16e7..dd6a3a0715e 100644
--- a/lib/Analysis/AliasAnalysisEvaluator.cpp
+++ b/lib/Analysis/AliasAnalysisEvaluator.cpp
@@ -219,8 +219,8 @@ bool AAEval::runOnFunction(Function &F) {
          I1 != E; ++I1) {
       for (SetVector<Value *>::iterator I2 = Stores.begin(), E2 = Stores.end();
            I2 != E2; ++I2) {
-        switch (AA.alias(AA.getLocation(cast<LoadInst>(*I1)),
-                         AA.getLocation(cast<StoreInst>(*I2)))) {
+        switch (AA.alias(MemoryLocation::get(cast<LoadInst>(*I1)),
+                         MemoryLocation::get(cast<StoreInst>(*I2)))) {
         case AliasAnalysis::NoAlias:
           PrintLoadStoreResults("NoAlias", PrintNoAlias, *I1, *I2,
                                 F.getParent());
@@ -245,8 +245,8 @@ bool AAEval::runOnFunction(Function &F) {
     for (SetVector<Value *>::iterator I1 = Stores.begin(), E = Stores.end();
          I1 != E; ++I1) {
       for (SetVector<Value *>::iterator I2 = Stores.begin(); I2 != I1; ++I2) {
-        switch (AA.alias(AA.getLocation(cast<StoreInst>(*I1)),
-                         AA.getLocation(cast<StoreInst>(*I2)))) {
+        switch (AA.alias(MemoryLocation::get(cast<StoreInst>(*I1)),
+                         MemoryLocation::get(cast<StoreInst>(*I2)))) {
         case AliasAnalysis::NoAlias:
           PrintLoadStoreResults("NoAlias", PrintNoAlias, *I1, *I2,
                                 F.getParent());
diff --git a/lib/Analysis/CMakeLists.txt b/lib/Analysis/CMakeLists.txt
index 32fe9b9495d..b22ee7e2493 100644
--- a/lib/Analysis/CMakeLists.txt
+++ b/lib/Analysis/CMakeLists.txt
@@ -42,6 +42,7 @@ add_llvm_library(LLVMAnalysis
   MemDerefPrinter.cpp
   MemoryBuiltins.cpp
   MemoryDependenceAnalysis.cpp
+  MemoryLocation.cpp
   ModuleDebugInfoPrinter.cpp
   NoAliasAnalysis.cpp
   PHITransAddr.cpp
diff --git a/lib/Analysis/LoopAccessAnalysis.cpp b/lib/Analysis/LoopAccessAnalysis.cpp
index b70de00db04..f21afd3ebbb 100644
--- a/lib/Analysis/LoopAccessAnalysis.cpp
+++ b/lib/Analysis/LoopAccessAnalysis.cpp
@@ -1066,7 +1066,7 @@ void LoopAccessInfo::analyzeLoop(const ValueToValueMap &Strides) {
     if (Seen.insert(Ptr).second) {
       ++NumReadWrites;
 
-      AliasAnalysis::Location Loc = AA->getLocation(ST);
+      AliasAnalysis::Location Loc = MemoryLocation::get(ST);
       // The TBAA metadata could have a control dependency on the predication
       // condition, so we cannot rely on it when determining whether or not we
       // need runtime pointer checks.
@@ -1102,7 +1102,7 @@ void LoopAccessInfo::analyzeLoop(const ValueToValueMap &Strides) {
       IsReadOnlyPtr = true;
     }
 
-    AliasAnalysis::Location Loc = AA->getLocation(LD);
+    AliasAnalysis::Location Loc = MemoryLocation::get(LD);
     // The TBAA metadata could have a control dependency on the predication
     // condition, so we cannot rely on it when determining whether or not we
     // need runtime pointer checks.
diff --git a/lib/Analysis/MemoryDependenceAnalysis.cpp b/lib/Analysis/MemoryDependenceAnalysis.cpp
index ecc1c9bda9b..255bae61eb2 100644
--- a/lib/Analysis/MemoryDependenceAnalysis.cpp
+++ b/lib/Analysis/MemoryDependenceAnalysis.cpp
@@ -124,11 +124,11 @@ AliasAnalysis::ModRefResult GetLocation(const Instruction *Inst,
                                         AliasAnalysis *AA) {
   if (const LoadInst *LI = dyn_cast<LoadInst>(Inst)) {
     if (LI->isUnordered()) {
-      Loc = AA->getLocation(LI);
+      Loc = MemoryLocation::get(LI);
       return AliasAnalysis::Ref;
     }
     if (LI->getOrdering() == Monotonic) {
-      Loc = AA->getLocation(LI);
+      Loc = MemoryLocation::get(LI);
       return AliasAnalysis::ModRef;
     }
     Loc = AliasAnalysis::Location();
@@ -137,11 +137,11 @@ AliasAnalysis::ModRefResult GetLocation(const Instruction *Inst,
 
   if (const StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
     if (SI->isUnordered()) {
-      Loc = AA->getLocation(SI);
+      Loc = MemoryLocation::get(SI);
       return AliasAnalysis::Mod;
     }
     if (SI->getOrdering() == Monotonic) {
-      Loc = AA->getLocation(SI);
+      Loc = MemoryLocation::get(SI);
       return AliasAnalysis::ModRef;
     }
     Loc = AliasAnalysis::Location();
@@ -149,7 +149,7 @@ AliasAnalysis::ModRefResult GetLocation(const Instruction *Inst,
   }
 
   if (const VAArgInst *V = dyn_cast<VAArgInst>(Inst)) {
-    Loc = AA->getLocation(V);
+    Loc = MemoryLocation::get(V);
     return AliasAnalysis::ModRef;
   }
 
@@ -486,7 +486,7 @@ getPointerDependencyFrom(const AliasAnalysis::Location &MemLoc, bool isLoad,
         }
       }
 
-      AliasAnalysis::Location LoadLoc = AA->getLocation(LI);
+      AliasAnalysis::Location LoadLoc = MemoryLocation::get(LI);
 
       // If we found a pointer, check if it could be the same as our pointer.
       AliasAnalysis::AliasResult R = AA->alias(LoadLoc, MemLoc);
@@ -575,7 +575,7 @@ getPointerDependencyFrom(const AliasAnalysis::Location &MemLoc, bool isLoad,
 
       // Ok, this store might clobber the query pointer.  Check to see if it is
       // a must alias: in this case, we want to return this as a def.
-      AliasAnalysis::Location StoreLoc = AA->getLocation(SI);
+      AliasAnalysis::Location StoreLoc = MemoryLocation::get(SI);
 
       // If we found a pointer, check if it could be the same as our pointer.
       AliasAnalysis::AliasResult R = AA->alias(StoreLoc, MemLoc);
@@ -872,7 +872,7 @@ MemoryDependenceAnalysis::getNonLocalCallDependency(CallSite QueryCS) {
 void MemoryDependenceAnalysis::
 getNonLocalPointerDependency(Instruction *QueryInst,
                              SmallVectorImpl<NonLocalDepResult> &Result) {
-  const AliasAnalysis::Location Loc = AA->getLocation(QueryInst);
+  const AliasAnalysis::Location Loc = MemoryLocation::get(QueryInst);
   bool isLoad = isa<LoadInst>(QueryInst);
   BasicBlock *FromBB = QueryInst->getParent();
   assert(FromBB);
diff --git a/lib/Analysis/MemoryLocation.cpp b/lib/Analysis/MemoryLocation.cpp
new file mode 100644
index 00000000000..f87a017b921
--- /dev/null
+++ b/lib/Analysis/MemoryLocation.cpp
@@ -0,0 +1,90 @@
+//===- MemoryLocation.cpp - Memory location descriptions -------------------==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Analysis/MemoryLocation.h"
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Type.h"
+using namespace llvm;
+
+MemoryLocation MemoryLocation::get(const LoadInst *LI) {
+  AAMDNodes AATags;
+  LI->getAAMetadata(AATags);
+  const auto &DL = LI->getModule()->getDataLayout();
+
+  return MemoryLocation(LI->getPointerOperand(),
+                        DL.getTypeStoreSize(LI->getType()), AATags);
+}
+
+MemoryLocation MemoryLocation::get(const StoreInst *SI) {
+  AAMDNodes AATags;
+  SI->getAAMetadata(AATags);
+  const auto &DL = SI->getModule()->getDataLayout();
+
+  return MemoryLocation(SI->getPointerOperand(),
+                        DL.getTypeStoreSize(SI->getValueOperand()->getType()),
+                        AATags);
+}
+
+MemoryLocation MemoryLocation::get(const VAArgInst *VI) {
+  AAMDNodes AATags;
+  VI->getAAMetadata(AATags);
+
+  return MemoryLocation(VI->getPointerOperand(), UnknownSize, AATags);
+}
+
+MemoryLocation MemoryLocation::get(const AtomicCmpXchgInst *CXI) {
+  AAMDNodes AATags;
+  CXI->getAAMetadata(AATags);
+  const auto &DL = CXI->getModule()->getDataLayout();
+
+  return MemoryLocation(
+      CXI->getPointerOperand(),
+      DL.getTypeStoreSize(CXI->getCompareOperand()->getType()), AATags);
+}
+
+MemoryLocation MemoryLocation::get(const AtomicRMWInst *RMWI) {
+  AAMDNodes AATags;
+  RMWI->getAAMetadata(AATags);
+  const auto &DL = RMWI->getModule()->getDataLayout();
+
+  return MemoryLocation(RMWI->getPointerOperand(),
+                        DL.getTypeStoreSize(RMWI->getValOperand()->getType()),
+                        AATags);
+}
+
+MemoryLocation MemoryLocation::getForSource(const MemTransferInst *MTI) {
+  uint64_t Size = UnknownSize;
+  if (ConstantInt *C = dyn_cast<ConstantInt>(MTI->getLength()))
+    Size = C->getValue().getZExtValue();
+
+  // memcpy/memmove can have AA tags. For memcpy, they apply
+  // to both the source and the destination.
+  AAMDNodes AATags;
+  MTI->getAAMetadata(AATags);
+
+  return MemoryLocation(MTI->getRawSource(), Size, AATags);
+}
+
+MemoryLocation MemoryLocation::getForDest(const MemIntrinsic *MTI) {
+  uint64_t Size = UnknownSize;
+  if (ConstantInt *C = dyn_cast<ConstantInt>(MTI->getLength()))
+    Size = C->getValue().getZExtValue();
+
+  // memcpy/memmove can have AA tags. For memcpy, they apply
+  // to both the source and the destination.
+  AAMDNodes AATags;
+  MTI->getAAMetadata(AATags);
+
+  return MemoryLocation(MTI->getRawDest(), Size, AATags);
+}
diff --git a/lib/Transforms/IPO/ArgumentPromotion.cpp b/lib/Transforms/IPO/ArgumentPromotion.cpp
index c70a9bcbf26..c7c57ab5644 100644
--- a/lib/Transforms/IPO/ArgumentPromotion.cpp
+++ b/lib/Transforms/IPO/ArgumentPromotion.cpp
@@ -553,7 +553,7 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg,
     LoadInst *Load = Loads[i];
     BasicBlock *BB = Load->getParent();
 
-    AliasAnalysis::Location Loc = AA.getLocation(Load);
+    AliasAnalysis::Location Loc = MemoryLocation::get(Load);
     if (AA.canInstructionRangeModRef(BB->front(), *Load, Loc,
         AliasAnalysis::Mod))
       return false;  // Pointer is invalidated!
diff --git a/lib/Transforms/IPO/FunctionAttrs.cpp b/lib/Transforms/IPO/FunctionAttrs.cpp
index 92e384a340a..ef8f42ffd6d 100644
--- a/lib/Transforms/IPO/FunctionAttrs.cpp
+++ b/lib/Transforms/IPO/FunctionAttrs.cpp
@@ -232,20 +232,20 @@ bool FunctionAttrs::AddReadAttrs(const CallGraphSCC &SCC) {
       } else if (LoadInst *LI = dyn_cast<LoadInst>(I)) {
         // Ignore non-volatile loads from local memory. (Atomic is okay here.)
         if (!LI->isVolatile()) {
-          AliasAnalysis::Location Loc = AA->getLocation(LI);
+          AliasAnalysis::Location Loc = MemoryLocation::get(LI);
           if (AA->pointsToConstantMemory(Loc, /*OrLocal=*/true))
             continue;
         }
       } else if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
         // Ignore non-volatile stores to local memory. (Atomic is okay here.)
         if (!SI->isVolatile()) {
-          AliasAnalysis::Location Loc = AA->getLocation(SI);
+          AliasAnalysis::Location Loc = MemoryLocation::get(SI);
           if (AA->pointsToConstantMemory(Loc, /*OrLocal=*/true))
             continue;
         }
       } else if (VAArgInst *VI = dyn_cast<VAArgInst>(I)) {
         // Ignore vaargs on local memory.
-        AliasAnalysis::Location Loc = AA->getLocation(VI);
+        AliasAnalysis::Location Loc = MemoryLocation::get(VI);
         if (AA->pointsToConstantMemory(Loc, /*OrLocal=*/true))
           continue;
       }
diff --git a/lib/Transforms/ObjCARC/ObjCARCContract.cpp b/lib/Transforms/ObjCARC/ObjCARCContract.cpp
index 2a3139f8705..e7731ad5cd1 100644
--- a/lib/Transforms/ObjCARC/ObjCARCContract.cpp
+++ b/lib/Transforms/ObjCARC/ObjCARCContract.cpp
@@ -200,7 +200,7 @@ static StoreInst *findSafeStoreForStoreStrongContraction(LoadInst *Load,
   bool SawRelease = false;
 
   // Get the location associated with Load.
-  AliasAnalysis::Location Loc = AA->getLocation(Load);
+  AliasAnalysis::Location Loc = MemoryLocation::get(Load);
 
   // Walk down to find the store and the release, which may be in either order.
   for (auto I = std::next(BasicBlock::iterator(Load)),
diff --git a/lib/Transforms/Scalar/DeadStoreElimination.cpp b/lib/Transforms/Scalar/DeadStoreElimination.cpp
index 01952cf6e8b..eb48a766a2c 100644
--- a/lib/Transforms/Scalar/DeadStoreElimination.cpp
+++ b/lib/Transforms/Scalar/DeadStoreElimination.cpp
@@ -197,11 +197,11 @@ static bool hasMemoryWrite(Instruction *I, const TargetLibraryInfo *TLI) {
 static AliasAnalysis::Location
 getLocForWrite(Instruction *Inst, AliasAnalysis &AA) {
   if (StoreInst *SI = dyn_cast<StoreInst>(Inst))
-    return AA.getLocation(SI);
+    return MemoryLocation::get(SI);
 
   if (MemIntrinsic *MI = dyn_cast<MemIntrinsic>(Inst)) {
     // memcpy/memmove/memset.
-    AliasAnalysis::Location Loc = AA.getLocationForDest(MI);
+    AliasAnalysis::Location Loc = MemoryLocation::getForDest(MI);
     return Loc;
   }
 
@@ -231,7 +231,7 @@ getLocForRead(Instruction *Inst, AliasAnalysis &AA) {
   // The only instructions that both read and write are the mem transfer
   // instructions (memcpy/memmove).
   if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(Inst))
-    return AA.getLocationForSource(MTI);
+    return MemoryLocation::getForSource(MTI);
   return AliasAnalysis::Location();
 }
 
@@ -815,11 +815,11 @@ bool DSE::handleEndBlock(BasicBlock &BB) {
     if (LoadInst *L = dyn_cast<LoadInst>(BBI)) {
       if (!L->isUnordered()) // Be conservative with atomic/volatile load
         break;
-      LoadedLoc = AA->getLocation(L);
+      LoadedLoc = MemoryLocation::get(L);
     } else if (VAArgInst *V = dyn_cast<VAArgInst>(BBI)) {
-      LoadedLoc = AA->getLocation(V);
+      LoadedLoc = MemoryLocation::get(V);
     } else if (MemTransferInst *MTI = dyn_cast<MemTransferInst>(BBI)) {
-      LoadedLoc = AA->getLocationForSource(MTI);
+      LoadedLoc = MemoryLocation::getForSource(MTI);
     } else if (!BBI->mayReadFromMemory()) {
       // Instruction doesn't read memory.  Note that stores that weren't removed
       // above will hit this case.
diff --git a/lib/Transforms/Scalar/MemCpyOptimizer.cpp b/lib/Transforms/Scalar/MemCpyOptimizer.cpp
index 66d6ac6f3a0..2bdf670f67e 100644
--- a/lib/Transforms/Scalar/MemCpyOptimizer.cpp
+++ b/lib/Transforms/Scalar/MemCpyOptimizer.cpp
@@ -510,7 +510,7 @@ bool MemCpyOpt::processStore(StoreInst *SI, BasicBlock::iterator &BBI) {
         // Check that nothing touches the dest of the "copy" between
         // the call and the store.
         AliasAnalysis &AA = getAnalysis<AliasAnalysis>();
-        AliasAnalysis::Location StoreLoc = AA.getLocation(SI);
+        AliasAnalysis::Location StoreLoc = MemoryLocation::get(SI);
         for (BasicBlock::iterator I = --BasicBlock::iterator(SI),
                                   E = C; I != E; --I) {
           if (AA.getModRefInfo(&*I, StoreLoc) != AliasAnalysis::NoModRef) {
@@ -802,9 +802,8 @@ bool MemCpyOpt::processMemCpyMemCpyDependence(MemCpyInst *M, MemCpyInst *MDep) {
   //
   // NOTE: This is conservative, it will stop on any read from the source loc,
   // not just the defining memcpy.
-  MemDepResult SourceDep =
-    MD->getPointerDependencyFrom(AA.getLocationForSource(MDep),
-                                 false, M, M->getParent());
+  MemDepResult SourceDep = MD->getPointerDependencyFrom(
+      MemoryLocation::getForSource(MDep), false, M, M->getParent());
   if (!SourceDep.isClobber() || SourceDep.getInst() != MDep)
     return false;
 
@@ -812,7 +811,8 @@ bool MemCpyOpt::processMemCpyMemCpyDependence(MemCpyInst *M, MemCpyInst *MDep) {
   // source and dest might overlap.  We still want to eliminate the intermediate
   // value, but we have to generate a memmove instead of memcpy.
   bool UseMemMove = false;
-  if (!AA.isNoAlias(AA.getLocationForDest(M), AA.getLocationForSource(MDep)))
+  if (!AA.isNoAlias(MemoryLocation::getForDest(M),
+                    MemoryLocation::getForSource(MDep)))
     UseMemMove = true;
 
   // If all checks passed, then we can transform M.
@@ -860,9 +860,8 @@ bool MemCpyOpt::processMemSetMemCpyDependence(MemCpyInst *MemCpy,
     return false;
 
   // Check that there are no other dependencies on the memset destination.
-  MemDepResult DstDepInfo =
-      MD->getPointerDependencyFrom(AliasAnalysis::getLocationForDest(MemSet),
-                                   false, MemCpy, MemCpy->getParent());
+  MemDepResult DstDepInfo = MD->getPointerDependencyFrom(
+      MemoryLocation::getForDest(MemSet), false, MemCpy, MemCpy->getParent());
   if (DstDepInfo.getInst() != MemSet)
     return false;
 
@@ -998,7 +997,7 @@ bool MemCpyOpt::processMemCpy(MemCpyInst *M) {
     }
   }
 
-  AliasAnalysis::Location SrcLoc = AliasAnalysis::getLocationForSource(M);
+  AliasAnalysis::Location SrcLoc = MemoryLocation::getForSource(M);
   MemDepResult SrcDepInfo = MD->getPointerDependencyFrom(SrcLoc, true,
                                                          M, M->getParent());
 
@@ -1047,7 +1046,8 @@ bool MemCpyOpt::processMemMove(MemMoveInst *M) {
     return false;
 
   // See if the pointers alias.
-  if (!AA.isNoAlias(AA.getLocationForDest(M), AA.getLocationForSource(M)))
+  if (!AA.isNoAlias(MemoryLocation::getForDest(M),
+                    MemoryLocation::getForSource(M)))
     return false;
 
   DEBUG(dbgs() << "MemCpyOpt: Optimizing memmove -> memcpy: " << *M << "\n");
@@ -1121,8 +1121,8 @@ bool MemCpyOpt::processByValArgument(CallSite CS, unsigned ArgNo) {
   // NOTE: This is conservative, it will stop on any read from the source loc,
   // not just the defining memcpy.
   MemDepResult SourceDep =
-    MD->getPointerDependencyFrom(AliasAnalysis::getLocationForSource(MDep),
-                                 false, CS.getInstruction(), MDep->getParent());
+      MD->getPointerDependencyFrom(MemoryLocation::getForSource(MDep), false,
+                                   CS.getInstruction(), MDep->getParent());
   if (!SourceDep.isClobber() || SourceDep.getInst() != MDep)
     return false;
 
diff --git a/lib/Transforms/Scalar/MergedLoadStoreMotion.cpp b/lib/Transforms/Scalar/MergedLoadStoreMotion.cpp
index 611a941b0b2..776dfb4d487 100644
--- a/lib/Transforms/Scalar/MergedLoadStoreMotion.cpp
+++ b/lib/Transforms/Scalar/MergedLoadStoreMotion.cpp
@@ -241,7 +241,7 @@ bool MergedLoadStoreMotion::isDiamondHead(BasicBlock *BB) {
 bool MergedLoadStoreMotion::isLoadHoistBarrierInRange(const Instruction& Start, 
                                                       const Instruction& End,
                                                       LoadInst* LI) {
-  AliasAnalysis::Location Loc = AA->getLocation(LI);
+  AliasAnalysis::Location Loc = MemoryLocation::get(LI);
   return AA->canInstructionRangeModRef(Start, End, Loc, AliasAnalysis::Mod);
 }
 
@@ -266,8 +266,8 @@ LoadInst *MergedLoadStoreMotion::canHoistFromBlock(BasicBlock *BB1,
     LoadInst *Load1 = dyn_cast<LoadInst>(Inst);
     BasicBlock *BB0 = Load0->getParent();
 
-    AliasAnalysis::Location Loc0 = AA->getLocation(Load0);
-    AliasAnalysis::Location Loc1 = AA->getLocation(Load1);
+    AliasAnalysis::Location Loc0 = MemoryLocation::get(Load0);
+    AliasAnalysis::Location Loc1 = MemoryLocation::get(Load1);
     if (AA->isMustAlias(Loc0, Loc1) && Load0->isSameOperationAs(Load1) &&
         !isLoadHoistBarrierInRange(BB1->front(), *Load1, Load1) &&
         !isLoadHoistBarrierInRange(BB0->front(), *Load0, Load0)) {
@@ -425,8 +425,8 @@ StoreInst *MergedLoadStoreMotion::canSinkFromBlock(BasicBlock *BB1,
 
     StoreInst *Store1 = cast<StoreInst>(Inst);
 
-    AliasAnalysis::Location Loc0 = AA->getLocation(Store0);
-    AliasAnalysis::Location Loc1 = AA->getLocation(Store1);
+    AliasAnalysis::Location Loc0 = MemoryLocation::get(Store0);
+    AliasAnalysis::Location Loc1 = MemoryLocation::get(Store1);
     if (AA->isMustAlias(Loc0, Loc1) && Store0->isSameOperationAs(Store1) &&
       !isStoreSinkBarrierInRange(*(std::next(BasicBlock::iterator(Store1))),
                                  BB1->back(), Loc1) &&
diff --git a/lib/Transforms/Scalar/Sink.cpp b/lib/Transforms/Scalar/Sink.cpp
index ec3a0186641..078c6a921a0 100644
--- a/lib/Transforms/Scalar/Sink.cpp
+++ b/lib/Transforms/Scalar/Sink.cpp
@@ -163,7 +163,7 @@ static bool isSafeToMove(Instruction *Inst, AliasAnalysis *AA,
   }
 
   if (LoadInst *L = dyn_cast<LoadInst>(Inst)) {
-    AliasAnalysis::Location Loc = AA->getLocation(L);
+    AliasAnalysis::Location Loc = MemoryLocation::get(L);
     for (Instruction *S : Stores)
       if (AA->getModRefInfo(S, Loc) & AliasAnalysis::Mod)
         return false;
diff --git a/lib/Transforms/Vectorize/SLPVectorizer.cpp b/lib/Transforms/Vectorize/SLPVectorizer.cpp
index 0e9d2948388..a3a45c80d85 100644
--- a/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -317,9 +317,9 @@ static bool InTreeUserNeedToExtract(Value *Scalar, Instruction *UserInst,
 /// \returns the AA location that is being access by the instruction.
 static AliasAnalysis::Location getLocation(Instruction *I, AliasAnalysis *AA) {
   if (StoreInst *SI = dyn_cast<StoreInst>(I))
-    return AA->getLocation(SI);
+    return MemoryLocation::get(SI);
   if (LoadInst *LI = dyn_cast<LoadInst>(I))
-    return AA->getLocation(LI);
+    return MemoryLocation::get(LI);
   return AliasAnalysis::Location();
 }