2 files changed, 36 insertions, 12 deletions

diff --git a/polly/lib/Support/SCEVValidator.cpp b/polly/lib/Support/SCEVValidator.cpp
index 85bda185ec3..9b3ce1860d5 100644
--- a/polly/lib/Support/SCEVValidator.cpp
+++ b/polly/lib/Support/SCEVValidator.cpp
@@ -8,6 +8,7 @@
 #include <vector>
 
 using namespace llvm;
+using namespace polly;
 
 #define DEBUG_TYPE "polly-scev-validator"
 
@@ -125,10 +126,12 @@ private:
   const Region *R;
   ScalarEvolution &SE;
   const Value *BaseAddress;
+  InvariantLoadsSetTy *ILS;
 
 public:
-  SCEVValidator(const Region *R, ScalarEvolution &SE, const Value *BaseAddress)
-      : R(R), SE(SE), BaseAddress(BaseAddress) {}
+  SCEVValidator(const Region *R, ScalarEvolution &SE, const Value *BaseAddress,
+                InvariantLoadsSetTy *ILS)
+      : R(R), SE(SE), BaseAddress(BaseAddress), ILS(ILS) {}
 
   class ValidatorResult visitConstant(const SCEVConstant *Constant) {
     return ValidatorResult(SCEVType::INT);
@@ -335,6 +338,15 @@ public:
     return ValidatorResult(SCEVType::PARAM, S);
   }
 
+  ValidatorResult visitLoadInstruction(Instruction *I, const SCEV *S) {
+    if (R->contains(I) && ILS) {
+      ILS->insert(cast<LoadInst>(I));
+      return ValidatorResult(SCEVType::PARAM, S);
+    }
+
+    return visitGenericInst(I, S);
+  }
+
   ValidatorResult visitSDivInstruction(Instruction *SDiv, const SCEV *S) {
     assert(SDiv->getOpcode() == Instruction::SDiv &&
            "Assumed SDiv instruction!");
@@ -391,6 +403,8 @@ public:
 
     if (Instruction *I = dyn_cast<Instruction>(Expr->getValue())) {
       switch (I->getOpcode()) {
+      case Instruction::Load:
+        return visitLoadInstruction(I, Expr);
       case Instruction::SDiv:
         return visitSDivInstruction(I, Expr);
       case Instruction::SRem:
@@ -550,11 +564,11 @@ bool hasScalarDepsInsideRegion(const SCEV *Expr, const Region *R) {
 }
 
 bool isAffineExpr(const Region *R, const SCEV *Expr, ScalarEvolution &SE,
-                  const Value *BaseAddress) {
+                  const Value *BaseAddress, InvariantLoadsSetTy *ILS) {
   if (isa<SCEVCouldNotCompute>(Expr))
     return false;
 
-  SCEVValidator Validator(R, SE, BaseAddress);
+  SCEVValidator Validator(R, SE, BaseAddress, ILS);
   DEBUG({
     dbgs() << "\n";
     dbgs() << "Expr: " << *Expr << "\n";
@@ -580,7 +594,8 @@ std::vector<const SCEV *> getParamsInAffineExpr(const Region *R,
   if (isa<SCEVCouldNotCompute>(Expr))
     return std::vector<const SCEV *>();
 
-  SCEVValidator Validator(R, SE, BaseAddress);
+  InvariantLoadsSetTy ILS;
+  SCEVValidator Validator(R, SE, BaseAddress, &ILS);
   ValidatorResult Result = Validator.visit(Expr);
   assert(Result.isValid() && "Requested parameters for an invalid SCEV!");
 
diff --git a/polly/lib/Support/ScopHelper.cpp b/polly/lib/Support/ScopHelper.cpp
index cc41d4812f7..d2123bd69eb 100644
--- a/polly/lib/Support/ScopHelper.cpp
+++ b/polly/lib/Support/ScopHelper.cpp
@@ -14,7 +14,6 @@
 #include "polly/Support/ScopHelper.h"
 #include "polly/Options.h"
 #include "polly/ScopInfo.h"
-#include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/RegionInfo.h"
 #include "llvm/Analysis/ScalarEvolution.h"
@@ -240,8 +239,6 @@ void polly::splitEntryBlockForAlloca(BasicBlock *EntryBlock, Pass *P) {
 struct ScopExpander : SCEVVisitor<ScopExpander, const SCEV *> {
   friend struct SCEVVisitor<ScopExpander, const SCEV *>;
 
-  typedef llvm::DenseMap<const llvm::Value *, llvm::Value *> ValueMapT;
-
   explicit ScopExpander(const Region &R, ScalarEvolution &SE,
                         const DataLayout &DL, const char *Name, ValueMapT *VMap)
       : Expander(SCEVExpander(SE, DL, Name)), SE(SE), Name(Name), R(R),
@@ -342,10 +339,9 @@ private:
   ///}
 };
 
-Value *
-polly::expandCodeFor(Scop &S, ScalarEvolution &SE, const DataLayout &DL,
-                     const char *Name, const SCEV *E, Type *Ty, Instruction *IP,
-                     llvm::DenseMap<const llvm::Value *, llvm::Value *> *VMap) {
+Value *polly::expandCodeFor(Scop &S, ScalarEvolution &SE, const DataLayout &DL,
+                            const char *Name, const SCEV *E, Type *Ty,
+                            Instruction *IP, ValueMapT *VMap) {
   ScopExpander Expander(S.getRegion(), SE, DL, Name, VMap);
   return Expander.expandCodeFor(E, Ty, IP);
 }
@@ -383,3 +379,16 @@ Value *polly::getConditionFromTerminator(TerminatorInst *TI) {
 
   return nullptr;
 }
+
+bool polly::isHoistableLoad(LoadInst *LInst, Region &R, LoopInfo &LI,
+                            ScalarEvolution &SE) {
+  Loop *L = LI.getLoopFor(LInst->getParent());
+  const SCEV *PtrSCEV = SE.getSCEVAtScope(LInst->getPointerOperand(), L);
+  while (L && R.contains(L)) {
+    if (!SE.isLoopInvariant(PtrSCEV, L))
+      return false;
+    L = L->getParentLoop();
+  }
+
+  return true;
+}