X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FAnalysis%2FCFG.cpp;h=0dfd57d3cb6bb985bd8c597236cb6ae23591c281;hb=e14c161b0e3691e5004303766678ec939155fd42;hp=9ebbb6784971b7ac6a890eb3259a2889fae65256;hpb=299918ad4813ded5eb717c0c4898eb67205d880b;p=oota-llvm.git

diff --git a/lib/Analysis/CFG.cpp b/lib/Analysis/CFG.cpp
index 9ebbb678497..0dfd57d3cb6 100644
--- a/lib/Analysis/CFG.cpp
+++ b/lib/Analysis/CFG.cpp
@@ -27,7 +27,7 @@ using namespace llvm;
 void llvm::FindFunctionBackedges(const Function &F,
      SmallVectorImpl<std::pair<const BasicBlock*,const BasicBlock*> > &Result) {
   const BasicBlock *BB = &F.getEntryBlock();
-  if (succ_begin(BB) == succ_end(BB))
+  if (succ_empty(BB))
     return;
 
   SmallPtrSet<const BasicBlock*, 8> Visited;
@@ -45,7 +45,7 @@ void llvm::FindFunctionBackedges(const Function &F,
     bool FoundNew = false;
     while (I != succ_end(ParentBB)) {
       BB = *I++;
-      if (Visited.insert(BB)) {
+      if (Visited.insert(BB).second) {
         FoundNew = true;
         break;
       }
@@ -69,8 +69,9 @@ void llvm::FindFunctionBackedges(const Function &F,
 /// and return its position in the terminator instruction's list of
 /// successors.  It is an error to call this with a block that is not a
 /// successor.
-unsigned llvm::GetSuccessorNumber(BasicBlock *BB, BasicBlock *Succ) {
-  TerminatorInst *Term = BB->getTerminator();
+unsigned llvm::GetSuccessorNumber(const BasicBlock *BB,
+    const BasicBlock *Succ) {
+  const TerminatorInst *Term = BB->getTerminator();
 #ifndef NDEBUG
   unsigned e = Term->getNumSuccessors();
 #endif
@@ -101,15 +102,9 @@ bool llvm::isCriticalEdge(const TerminatorInst *TI, unsigned SuccNum,
 
   // If AllowIdenticalEdges is true, then we allow this edge to be considered
   // non-critical iff all preds come from TI's block.
-  while (I != E) {
-    const BasicBlock *P = *I;
-    if (P != FirstPred)
+  for (; I != E; ++I)
+    if (*I != FirstPred)
       return true;
-    // Note: leave this as is until no one ever compiles with either gcc 4.0.1
-    // or Xcode 2. This seems to work around the pred_iterator assert in PR 2207
-    E = pred_end(P);
-    ++I;
-  }
   return false;
 }
 
@@ -129,17 +124,16 @@ static bool loopContainsBoth(const LoopInfo *LI,
                              const BasicBlock *BB1, const BasicBlock *BB2) {
   const Loop *L1 = getOutermostLoop(LI, BB1);
   const Loop *L2 = getOutermostLoop(LI, BB2);
-  return L1 != NULL && L1 == L2;
+  return L1 != nullptr && L1 == L2;
 }
 
-static bool isPotentiallyReachableInner(SmallVectorImpl<BasicBlock *> &Worklist,
-                                        BasicBlock *StopBB,
-                                        const DominatorTree *DT,
-                                        const LoopInfo *LI) {
+bool llvm::isPotentiallyReachableFromMany(
+    SmallVectorImpl<BasicBlock *> &Worklist, BasicBlock *StopBB,
+    const DominatorTree *DT, const LoopInfo *LI) {
   // When the stop block is unreachable, it's dominated from everywhere,
   // regardless of whether there's a path between the two blocks.
   if (DT && !DT->isReachableFromEntry(StopBB))
-    DT = 0;
+    DT = nullptr;
 
   // Limit the number of blocks we visit. The goal is to avoid run-away compile
   // times on large CFGs without hampering sensible code. Arbitrarily chosen.
@@ -147,7 +141,7 @@ static bool isPotentiallyReachableInner(SmallVectorImpl<BasicBlock *> &Worklist,
   SmallSet<const BasicBlock*, 64> Visited;
   do {
     BasicBlock *BB = Worklist.pop_back_val();
-    if (!Visited.insert(BB))
+    if (!Visited.insert(BB).second)
       continue;
     if (BB == StopBB)
       return true;
@@ -162,7 +156,7 @@ static bool isPotentiallyReachableInner(SmallVectorImpl<BasicBlock *> &Worklist,
       return true;
     }
 
-    if (const Loop *Outer = LI ? getOutermostLoop(LI, BB) : 0) {
+    if (const Loop *Outer = LI ? getOutermostLoop(LI, BB) : nullptr) {
       // All blocks in a single loop are reachable from all other blocks. From
       // any of these blocks, we can skip directly to the exits of the loop,
       // ignoring any other blocks inside the loop body.
@@ -185,8 +179,8 @@ bool llvm::isPotentiallyReachable(const BasicBlock *A, const BasicBlock *B,
   SmallVector<BasicBlock*, 32> Worklist;
   Worklist.push_back(const_cast<BasicBlock*>(A));
 
-  return isPotentiallyReachableInner(Worklist, const_cast<BasicBlock*>(B),
-                                     DT, LI);
+  return isPotentiallyReachableFromMany(Worklist, const_cast<BasicBlock *>(B),
+                                        DT, LI);
 }
 
 bool llvm::isPotentiallyReachable(const Instruction *A, const Instruction *B,
@@ -206,11 +200,12 @@ bool llvm::isPotentiallyReachable(const Instruction *A, const Instruction *B,
 
     // If the block is in a loop then we can reach any instruction in the block
     // from any other instruction in the block by going around a backedge.
-    if (LI && LI->getLoopFor(BB) != 0)
+    if (LI && LI->getLoopFor(BB) != nullptr)
       return true;
 
     // Linear scan, start at 'A', see whether we hit 'B' or the end first.
-    for (BasicBlock::const_iterator I = A, E = BB->end(); I != E; ++I) {
+    for (BasicBlock::const_iterator I = A->getIterator(), E = BB->end(); I != E;
+         ++I) {
       if (&*I == B)
         return true;
     }
@@ -236,7 +231,6 @@ bool llvm::isPotentiallyReachable(const Instruction *A, const Instruction *B,
   if (B->getParent() == &A->getParent()->getParent()->getEntryBlock())
     return false;
 
-  return isPotentiallyReachableInner(Worklist,
-                                     const_cast<BasicBlock*>(B->getParent()),
-                                     DT, LI);
+  return isPotentiallyReachableFromMany(
+      Worklist, const_cast<BasicBlock *>(B->getParent()), DT, LI);
 }