Revamp PredIteratorCache interface to be cleaner.

Summary:
This lets us use range based for loops.

Reviewers: chandlerc

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9169

llvm-svn: 235416

3 files changed, 18 insertions, 21 deletions

diff --git a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
index 84769cb07d7..3c1826a58e6 100644
--- a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
+++ b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
@@ -65,7 +65,7 @@ INITIALIZE_PASS_END(MemoryDependenceAnalysis, "memdep",
                       "Memory Dependence Analysis", false, true)
 
 MemoryDependenceAnalysis::MemoryDependenceAnalysis()
-    : FunctionPass(ID), PredCache() {
+    : FunctionPass(ID) {
   initializeMemoryDependenceAnalysisPass(*PassRegistry::getPassRegistry());
 }
 MemoryDependenceAnalysis::~MemoryDependenceAnalysis() {
@@ -79,7 +79,7 @@ void MemoryDependenceAnalysis::releaseMemory() {
   ReverseLocalDeps.clear();
   ReverseNonLocalDeps.clear();
   ReverseNonLocalPtrDeps.clear();
-  PredCache->clear();
+  PredCache.clear();
 }
 
 /// getAnalysisUsage - Does not modify anything.  It uses Alias Analysis.
@@ -96,8 +96,6 @@ bool MemoryDependenceAnalysis::runOnFunction(Function &F) {
   DominatorTreeWrapperPass *DTWP =
       getAnalysisIfAvailable<DominatorTreeWrapperPass>();
   DT = DTWP ? &DTWP->getDomTree() : nullptr;
-  if (!PredCache)
-    PredCache.reset(new PredIteratorCache());
   return false;
 }
 
@@ -770,8 +768,8 @@ MemoryDependenceAnalysis::getNonLocalCallDependency(CallSite QueryCS) {
   } else {
     // Seed DirtyBlocks with each of the preds of QueryInst's block.
     BasicBlock *QueryBB = QueryCS.getInstruction()->getParent();
-    for (BasicBlock **PI = PredCache->GetPreds(QueryBB); *PI; ++PI)
-      DirtyBlocks.push_back(*PI);
+    for (BasicBlock *Pred : PredCache.get(QueryBB))
+      DirtyBlocks.push_back(Pred);
     ++NumUncacheNonLocal;
   }
 
@@ -856,8 +854,8 @@ MemoryDependenceAnalysis::getNonLocalCallDependency(CallSite QueryCS) {
 
       // If the block *is* completely transparent to the load, we need to check
       // the predecessors of this block.  Add them to our worklist.
-      for (BasicBlock **PI = PredCache->GetPreds(DirtyBB); *PI; ++PI)
-        DirtyBlocks.push_back(*PI);
+      for (BasicBlock *Pred : PredCache.get(DirtyBB))
+        DirtyBlocks.push_back(Pred);
     }
   }
 
@@ -1232,13 +1230,13 @@ getNonLocalPointerDepFromBB(Instruction *QueryInst,
     if (!Pointer.NeedsPHITranslationFromBlock(BB)) {
       SkipFirstBlock = false;
       SmallVector<BasicBlock*, 16> NewBlocks;
-      for (BasicBlock **PI = PredCache->GetPreds(BB); *PI; ++PI) {
+      for (BasicBlock *Pred : PredCache.get(BB)) {
         // Verify that we haven't looked at this block yet.
         std::pair<DenseMap<BasicBlock*,Value*>::iterator, bool>
-          InsertRes = Visited.insert(std::make_pair(*PI, Pointer.getAddr()));
+          InsertRes = Visited.insert(std::make_pair(Pred, Pointer.getAddr()));
         if (InsertRes.second) {
           // First time we've looked at *PI.
-          NewBlocks.push_back(*PI);
+          NewBlocks.push_back(Pred);
           continue;
         }
 
@@ -1274,8 +1272,7 @@ getNonLocalPointerDepFromBB(Instruction *QueryInst,
     Cache = nullptr;
 
     PredList.clear();
-    for (BasicBlock **PI = PredCache->GetPreds(BB); *PI; ++PI) {
-      BasicBlock *Pred = *PI;
+    for (BasicBlock *Pred : PredCache.get(BB)) {
       PredList.push_back(std::make_pair(Pred, Pointer));
 
       // Get the PHI translated pointer in this predecessor.  This can fail if
@@ -1465,7 +1462,7 @@ void MemoryDependenceAnalysis::invalidateCachedPointerInfo(Value *Ptr) {
 /// This needs to be done when the CFG changes, e.g., due to splitting
 /// critical edges.
 void MemoryDependenceAnalysis::invalidateCachedPredecessors() {
-  PredCache->clear();
+  PredCache.clear();
 }
 
 /// removeInstruction - Remove an instruction from the dependence analysis,
diff --git a/llvm/lib/Transforms/Scalar/LICM.cpp b/llvm/lib/Transforms/Scalar/LICM.cpp
index 1333b024f7b..0b98f6c2c12 100644
--- a/llvm/lib/Transforms/Scalar/LICM.cpp
+++ b/llvm/lib/Transforms/Scalar/LICM.cpp
@@ -704,10 +704,10 @@ namespace {
             // We need to create an LCSSA PHI node for the incoming value and
             // store that.
             PHINode *PN = PHINode::Create(
-                I->getType(), PredCache.GetNumPreds(BB),
+                I->getType(), PredCache.size(BB),
                 I->getName() + ".lcssa", BB->begin());
-            for (BasicBlock **PI = PredCache.GetPreds(BB); *PI; ++PI)
-              PN->addIncoming(I, *PI);
+            for (BasicBlock *Pred : PredCache.get(BB))
+              PN->addIncoming(I, Pred);
             return PN;
           }
       return V;
diff --git a/llvm/lib/Transforms/Utils/LCSSA.cpp b/llvm/lib/Transforms/Utils/LCSSA.cpp
index 1cba367a3e4..cf155a6487a 100644
--- a/llvm/lib/Transforms/Utils/LCSSA.cpp
+++ b/llvm/lib/Transforms/Utils/LCSSA.cpp
@@ -112,17 +112,17 @@ static bool processInstruction(Loop &L, Instruction &Inst, DominatorTree &DT,
     if (SSAUpdate.HasValueForBlock(ExitBB))
       continue;
 
-    PHINode *PN = PHINode::Create(Inst.getType(), PredCache.GetNumPreds(ExitBB),
+    PHINode *PN = PHINode::Create(Inst.getType(), PredCache.size(ExitBB),
                                   Inst.getName() + ".lcssa", ExitBB->begin());
 
     // Add inputs from inside the loop for this PHI.
-    for (BasicBlock **PI = PredCache.GetPreds(ExitBB); *PI; ++PI) {
-      PN->addIncoming(&Inst, *PI);
+    for (BasicBlock *Pred : PredCache.get(ExitBB)) {
+      PN->addIncoming(&Inst, Pred);
 
       // If the exit block has a predecessor not within the loop, arrange for
       // the incoming value use corresponding to that predecessor to be
       // rewritten in terms of a different LCSSA PHI.
-      if (!L.contains(*PI))
+      if (!L.contains(Pred))
         UsesToRewrite.push_back(
             &PN->getOperandUse(PN->getOperandNumForIncomingValue(
                  PN->getNumIncomingValues() - 1)));