Convert a bunch of loops to foreach. NFC.

After r244074, we now have a successors() method to iterate over
all the successors of a TerminatorInst.  This commit changes a bunch
of eligible loops to use it.

llvm-svn: 244260

8 files changed, 16 insertions, 23 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index d04ae07..45994d1 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -2927,8 +2927,8 @@ static bool AddReachableCodeToWorklist(BasicBlock *BB, const DataLayout &DL,
       }
     }
 
-    for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
-      Worklist.push_back(TI->getSuccessor(i));
+    for (BasicBlock *SuccBB : TI->successors())
+      Worklist.push_back(SuccBB);
   } while (!Worklist.empty());
 
   // Once we've found all of the instructions to add to instcombine's worklist,
diff --git a/llvm/lib/Transforms/Scalar/LoopRotation.cpp b/llvm/lib/Transforms/Scalar/LoopRotation.cpp
index bf034bc..770a549 100644
--- a/llvm/lib/Transforms/Scalar/LoopRotation.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopRotation.cpp
@@ -467,8 +467,8 @@ bool LoopRotate::rotateLoop(Loop *L, bool SimplifiedLatch) {
   // terminator into OrigPreHeader. Fix up the PHI nodes in each of OrigHeader's
   // successors by duplicating their incoming values for OrigHeader.
   TerminatorInst *TI = OrigHeader->getTerminator();
-  for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
-    for (BasicBlock::iterator BI = TI->getSuccessor(i)->begin();
+  for (BasicBlock *SuccBB : TI->successors())
+    for (BasicBlock::iterator BI = SuccBB->begin();
          PHINode *PN = dyn_cast<PHINode>(BI); ++BI)
       PN->addIncoming(PN->getIncomingValueForBlock(OrigHeader), OrigPreheader);
 
diff --git a/llvm/lib/Transforms/Scalar/SCCP.cpp b/llvm/lib/Transforms/Scalar/SCCP.cpp
index 84af253..5d072d6 100644
--- a/llvm/lib/Transforms/Scalar/SCCP.cpp
+++ b/llvm/lib/Transforms/Scalar/SCCP.cpp
@@ -1796,10 +1796,9 @@ bool IPSCCP::runOnModule(Module &M) {
         MadeChanges = true;
 
         TerminatorInst *TI = BB->getTerminator();
-        for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i) {
-          BasicBlock *Succ = TI->getSuccessor(i);
+        for (BasicBlock *Succ : TI->successors()) {
           if (!Succ->empty() && isa<PHINode>(Succ->begin()))
-            TI->getSuccessor(i)->removePredecessor(BB);
+            Succ->removePredecessor(BB);
         }
         if (!TI->use_empty())
           TI->replaceAllUsesWith(UndefValue::get(TI->getType()));
diff --git a/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp b/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp
index 4f23e20..28812a4 100644
--- a/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp
+++ b/llvm/lib/Transforms/Scalar/StructurizeCFG.cpp
@@ -358,13 +358,9 @@ void StructurizeCFG::analyzeLoops(RegionNode *N) {
     BasicBlock *BB = N->getNodeAs<BasicBlock>();
     BranchInst *Term = cast<BranchInst>(BB->getTerminator());
 
-    for (unsigned i = 0, e = Term->getNumSuccessors(); i != e; ++i) {
-      BasicBlock *Succ = Term->getSuccessor(i);
-
-      if (Visited.count(Succ)) {
+    for (BasicBlock *Succ : Term->successors())
+      if (Visited.count(Succ))
         Loops[Succ] = BB;
-      }
-    }
   }
 }
 
diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index 1bf92e3..d59eef3 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -41,8 +41,8 @@ void llvm::DeleteDeadBlock(BasicBlock *BB) {
 
   // Loop through all of our successors and make sure they know that one
   // of their predecessors is going away.
-  for (unsigned i = 0, e = BBTerm->getNumSuccessors(); i != e; ++i)
-    BBTerm->getSuccessor(i)->removePredecessor(BB);
+  for (BasicBlock *Succ : BBTerm->successors())
+    Succ->removePredecessor(BB);
 
   // Zap all the instructions in the block.
   while (!BB->empty()) {
diff --git a/llvm/lib/Transforms/Utils/CloneFunction.cpp b/llvm/lib/Transforms/Utils/CloneFunction.cpp
index cc4d6c6..cf11119 100644
--- a/llvm/lib/Transforms/Utils/CloneFunction.cpp
+++ b/llvm/lib/Transforms/Utils/CloneFunction.cpp
@@ -400,8 +400,8 @@ void PruningFunctionCloner::CloneBlock(const BasicBlock *BB,
       // If the director says to skip with a terminate instruction, we still
       // need to clone this block's successors.
       const TerminatorInst *TI = NewBB->getTerminator();
-      for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
-        ToClone.push_back(TI->getSuccessor(i));
+      for (const BasicBlock *Succ : TI->successors())
+        ToClone.push_back(Succ);
       return;
     }
     assert(Action != CloningDirector::SkipInstruction && 
@@ -450,8 +450,8 @@ void PruningFunctionCloner::CloneBlock(const BasicBlock *BB,
     
     // Recursively clone any reachable successor blocks.
     const TerminatorInst *TI = BB->getTerminator();
-    for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
-      ToClone.push_back(TI->getSuccessor(i));
+    for (const BasicBlock *Succ : TI->successors())
+      ToClone.push_back(Succ);
   }
   
   if (CodeInfo) {
diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 71a55d4..3483032 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -188,9 +188,8 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB, bool DeleteDeadConditions,
       BasicBlock *BB = SI->getParent();
 
       // Remove entries from PHI nodes which we no longer branch to...
-      for (unsigned i = 0, e = SI->getNumSuccessors(); i != e; ++i) {
+      for (BasicBlock *Succ : SI->successors()) {
         // Found case matching a constant operand?
-        BasicBlock *Succ = SI->getSuccessor(i);
         if (Succ == TheOnlyDest)
           TheOnlyDest = nullptr; // Don't modify the first branch to TheOnlyDest
         else
diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
index 8a0bd60..874604d 100644
--- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -2565,8 +2565,7 @@ static bool SimplifyTerminatorOnSelect(TerminatorInst *OldTerm, Value *Cond,
   BasicBlock *KeepEdge2 = TrueBB != FalseBB ? FalseBB : nullptr;
 
   // Then remove the rest.
-  for (unsigned I = 0, E = OldTerm->getNumSuccessors(); I != E; ++I) {
-    BasicBlock *Succ = OldTerm->getSuccessor(I);
+  for (BasicBlock *Succ : OldTerm->successors()) {
     // Make sure only to keep exactly one copy of each edge.
     if (Succ == KeepEdge1)
       KeepEdge1 = nullptr;