X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FAnalysis%2FDependenceAnalysis.cpp;h=d0784f1e678dba3e87ef396a7fb8c18a015831b3;hb=a49b463a19a9f8818d6f88211f710a407f3daaef;hp=57231b8325a3e909f05f94f8c136a7ca25cda4e5;hpb=754e940865aaf63be79dcb921572eff4b1042c7c;p=oota-llvm.git

diff --git a/lib/Analysis/DependenceAnalysis.cpp b/lib/Analysis/DependenceAnalysis.cpp
index 57231b8325a..d0784f1e678 100644
--- a/lib/Analysis/DependenceAnalysis.cpp
+++ b/lib/Analysis/DependenceAnalysis.cpp
@@ -3180,9 +3180,21 @@ void DependenceAnalysis::updateDirection(Dependence::DVEntry &Level,
 /// source and destination array references are recurrences on a nested loop,
 /// this function flattens the nested recurrences into separate recurrences
 /// for each loop level.
-bool
-DependenceAnalysis::tryDelinearize(const SCEV *SrcSCEV, const SCEV *DstSCEV,
-                                   SmallVectorImpl<Subscript> &Pair) const {
+bool DependenceAnalysis::tryDelinearize(const SCEV *SrcSCEV,
+                                        const SCEV *DstSCEV,
+                                        SmallVectorImpl<Subscript> &Pair,
+                                        const SCEV *ElementSize) const {
+  const SCEVUnknown *SrcBase =
+      dyn_cast<SCEVUnknown>(SE->getPointerBase(SrcSCEV));
+  const SCEVUnknown *DstBase =
+      dyn_cast<SCEVUnknown>(SE->getPointerBase(DstSCEV));
+
+  if (!SrcBase || !DstBase || SrcBase != DstBase)
+    return false;
+
+  SrcSCEV = SE->getMinusSCEV(SrcSCEV, SrcBase);
+  DstSCEV = SE->getMinusSCEV(DstSCEV, DstBase);
+
   const SCEVAddRecExpr *SrcAR = dyn_cast<SCEVAddRecExpr>(SrcSCEV);
   const SCEVAddRecExpr *DstAR = dyn_cast<SCEVAddRecExpr>(DstSCEV);
   if (!SrcAR || !DstAR || !SrcAR->isAffine() || !DstAR->isAffine())
@@ -3195,24 +3207,18 @@ DependenceAnalysis::tryDelinearize(const SCEV *SrcSCEV, const SCEV *DstSCEV,
 
   // Second step: find subscript sizes.
   SmallVector<const SCEV *, 4> Sizes;
-  SE->findArrayDimensions(Terms, Sizes);
+  SE->findArrayDimensions(Terms, Sizes, ElementSize);
 
   // Third step: compute the access functions for each subscript.
   SmallVector<const SCEV *, 4> SrcSubscripts, DstSubscripts;
-  const SCEV *RemainderS = SrcAR->computeAccessFunctions(*SE, SrcSubscripts, Sizes);
-  const SCEV *RemainderD = DstAR->computeAccessFunctions(*SE, DstSubscripts, Sizes);
+  SrcAR->computeAccessFunctions(*SE, SrcSubscripts, Sizes);
+  DstAR->computeAccessFunctions(*SE, DstSubscripts, Sizes);
 
   // Fail when there is only a subscript: that's a linearized access function.
   if (SrcSubscripts.size() < 2 || DstSubscripts.size() < 2 ||
       SrcSubscripts.size() != DstSubscripts.size())
     return false;
 
-  // When the difference in remainders is different than a constant it might be
-  // that the base address of the arrays is not the same.
-  const SCEV *DiffRemainders = SE->getMinusSCEV(RemainderS, RemainderD);
-  if (!isa<SCEVConstant>(DiffRemainders))
-    return false;
-
   int size = SrcSubscripts.size();
 
   DEBUG({
@@ -3353,7 +3359,7 @@ Dependence *DependenceAnalysis::depends(Instruction *Src,
   }
 
   if (Delinearize && Pairs == 1 && CommonLevels > 1 &&
-      tryDelinearize(Pair[0].Src, Pair[0].Dst, Pair)) {
+      tryDelinearize(Pair[0].Src, Pair[0].Dst, Pair, SE->getElementSize(Src))) {
     DEBUG(dbgs() << "    delinerized GEP\n");
     Pairs = Pair.size();
   }
@@ -3777,7 +3783,7 @@ const  SCEV *DependenceAnalysis::getSplitIteration(const Dependence *Dep,
   }
 
   if (Delinearize && Pairs == 1 && CommonLevels > 1 &&
-      tryDelinearize(Pair[0].Src, Pair[0].Dst, Pair)) {
+      tryDelinearize(Pair[0].Src, Pair[0].Dst, Pair, SE->getElementSize(Src))) {
     DEBUG(dbgs() << "    delinerized GEP\n");
     Pairs = Pair.size();
   }