Use do+while instead of while for loops which obviously have a

non-zero trip count. Use SmallVector's pop_back_val().


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92734 91177308-0d34-0410-b5e6-96231b3b80d8

12 files changed, 23 insertions, 29 deletions

diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp
index 218e7ae229..8e59c01da8 100644
--- a/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -1000,9 +1000,8 @@ static bool AddReachableCodeToWorklist(BasicBlock *BB,
 
   SmallPtrSet<ConstantExpr*, 64> FoldedConstants;
   
-  while (!Worklist.empty()) {
-    BB = Worklist.back();
-    Worklist.pop_back();
+  do {
+    BB = Worklist.pop_back_val();
     
     // We have now visited this block!  If we've already been here, ignore it.
     if (!Visited.insert(BB)) continue;
@@ -1082,7 +1081,7 @@ static bool AddReachableCodeToWorklist(BasicBlock *BB,
     
     for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
       Worklist.push_back(TI->getSuccessor(i));
-  }
+  } while (!Worklist.empty());
   
   // Once we've found all of the instructions to add to instcombine's worklist,
   // add them in reverse order.  This way instcombine will visit from the top
diff --git a/lib/Transforms/Scalar/ADCE.cpp b/lib/Transforms/Scalar/ADCE.cpp
index 37f383fb51..5a4984158e 100644
--- a/lib/Transforms/Scalar/ADCE.cpp
+++ b/lib/Transforms/Scalar/ADCE.cpp
@@ -62,8 +62,7 @@ bool ADCE::runOnFunction(Function& F) {
   
   // Propagate liveness backwards to operands.
   while (!worklist.empty()) {
-    Instruction* curr = worklist.back();
-    worklist.pop_back();
+    Instruction* curr = worklist.pop_back_val();
     
     for (Instruction::op_iterator OI = curr->op_begin(), OE = curr->op_end();
          OI != OE; ++OI)
diff --git a/lib/Transforms/Scalar/DeadStoreElimination.cpp b/lib/Transforms/Scalar/DeadStoreElimination.cpp
index f84735d0a1..320afa19d5 100644
--- a/lib/Transforms/Scalar/DeadStoreElimination.cpp
+++ b/lib/Transforms/Scalar/DeadStoreElimination.cpp
@@ -523,9 +523,8 @@ void DSE::DeleteDeadInstruction(Instruction *I,
 
   // Before we touch this instruction, remove it from memdep!
   MemoryDependenceAnalysis &MDA = getAnalysis<MemoryDependenceAnalysis>();
-  while (!NowDeadInsts.empty()) {
-    Instruction *DeadInst = NowDeadInsts.back();
-    NowDeadInsts.pop_back();
+  do {
+    Instruction *DeadInst = NowDeadInsts.pop_back_val();
     
     ++NumFastOther;
     
@@ -549,7 +548,7 @@ void DSE::DeleteDeadInstruction(Instruction *I,
     DeadInst->eraseFromParent();
     
     if (ValueSet) ValueSet->erase(DeadInst);
-  }
+  } while (!NowDeadInsts.empty());
 }
 
 unsigned DSE::getPointerSize(Value *V) const {
diff --git a/lib/Transforms/Scalar/GVN.cpp b/lib/Transforms/Scalar/GVN.cpp
index 85b21e1fab..ac0d850360 100644
--- a/lib/Transforms/Scalar/GVN.cpp
+++ b/lib/Transforms/Scalar/GVN.cpp
@@ -829,7 +829,7 @@ SpeculationFailure:
   SmallVector<BasicBlock*, 32> BBWorklist;
   BBWorklist.push_back(BB);
 
-  while (!BBWorklist.empty()) {
+  do {
     BasicBlock *Entry = BBWorklist.pop_back_val();
     // Note that this sets blocks to 0 (unavailable) if they happen to not
     // already be in FullyAvailableBlocks.  This is safe.
@@ -841,7 +841,7 @@ SpeculationFailure:
 
     for (succ_iterator I = succ_begin(Entry), E = succ_end(Entry); I != E; ++I)
       BBWorklist.push_back(*I);
-  }
+  } while (!BBWorklist.empty());
 
   return false;
 }
diff --git a/lib/Transforms/Scalar/LoopIndexSplit.cpp b/lib/Transforms/Scalar/LoopIndexSplit.cpp
index 1d9dd68412..16d3f2f703 100644
--- a/lib/Transforms/Scalar/LoopIndexSplit.cpp
+++ b/lib/Transforms/Scalar/LoopIndexSplit.cpp
@@ -708,7 +708,7 @@ void LoopIndexSplit::removeBlocks(BasicBlock *DeadBB, Loop *LP,
   }
 
   while (!WorkList.empty()) {
-    BasicBlock *BB = WorkList.back(); WorkList.pop_back();
+    BasicBlock *BB = WorkList.pop_back_val();
     LPM->deleteSimpleAnalysisValue(BB, LP);
     for(BasicBlock::iterator BBI = BB->begin(), BBE = BB->end(); 
         BBI != BBE; ) {
@@ -726,7 +726,7 @@ void LoopIndexSplit::removeBlocks(BasicBlock *DeadBB, Loop *LP,
 
   // Update Frontier BBs' dominator info.
   while (!FrontierBBs.empty()) {
-    BasicBlock *FBB = FrontierBBs.back(); FrontierBBs.pop_back();
+    BasicBlock *FBB = FrontierBBs.pop_back_val();
     BasicBlock *NewDominator = FBB->getSinglePredecessor();
     if (!NewDominator) {
       pred_iterator PI = pred_begin(FBB), PE = pred_end(FBB);
diff --git a/lib/Transforms/Scalar/MemCpyOptimizer.cpp b/lib/Transforms/Scalar/MemCpyOptimizer.cpp
index c6756938cf..5f3fbbfbe5 100644
--- a/lib/Transforms/Scalar/MemCpyOptimizer.cpp
+++ b/lib/Transforms/Scalar/MemCpyOptimizer.cpp
@@ -562,8 +562,7 @@ bool MemCpyOpt::performCallSlotOptzn(MemCpyInst *cpy, CallInst *C) {
   SmallVector<User*, 8> srcUseList(srcAlloca->use_begin(),
                                    srcAlloca->use_end());
   while (!srcUseList.empty()) {
-    User *UI = srcUseList.back();
-    srcUseList.pop_back();
+    User *UI = srcUseList.pop_back_val();
 
     if (isa<BitCastInst>(UI)) {
       for (User::use_iterator I = UI->use_begin(), E = UI->use_end();
diff --git a/lib/Transforms/Scalar/SCCVN.cpp b/lib/Transforms/Scalar/SCCVN.cpp
index f91fbdaa4f..9685a2945f 100644
--- a/lib/Transforms/Scalar/SCCVN.cpp
+++ b/lib/Transforms/Scalar/SCCVN.cpp
@@ -678,8 +678,7 @@ bool SCCVN::runOnFunction(Function& F) {
           stack.push_back(*PI);
       
       while (!stack.empty()) {
-        BasicBlock* CurrBB = stack.back();
-        stack.pop_back();
+        BasicBlock* CurrBB = stack.pop_back_val();
         visited.insert(CurrBB);
         
         ValueNumberScope* S = BBMap[CurrBB];
diff --git a/lib/Transforms/Scalar/ScalarReplAggregates.cpp b/lib/Transforms/Scalar/ScalarReplAggregates.cpp
index 604c21083d..9e1e79a1c2 100644
--- a/lib/Transforms/Scalar/ScalarReplAggregates.cpp
+++ b/lib/Transforms/Scalar/ScalarReplAggregates.cpp
@@ -1181,7 +1181,7 @@ void SROA::CleanupAllocaUsers(Value *V) {
     if (!isa<StoreInst>(I) && OnlyUsedByDbgInfoIntrinsics(I, &DbgInUses)) {
       // Safe to remove debug info uses.
       while (!DbgInUses.empty()) {
-        DbgInfoIntrinsic *DI = DbgInUses.back(); DbgInUses.pop_back();
+        DbgInfoIntrinsic *DI = DbgInUses.pop_back_val();
         DI->eraseFromParent();
       }
       I->eraseFromParent();
diff --git a/lib/Transforms/Scalar/SimplifyCFGPass.cpp b/lib/Transforms/Scalar/SimplifyCFGPass.cpp
index a36da78519..43447de079 100644
--- a/lib/Transforms/Scalar/SimplifyCFGPass.cpp
+++ b/lib/Transforms/Scalar/SimplifyCFGPass.cpp
@@ -99,9 +99,8 @@ static bool MarkAliveBlocks(BasicBlock *BB,
   SmallVector<BasicBlock*, 128> Worklist;
   Worklist.push_back(BB);
   bool Changed = false;
-  while (!Worklist.empty()) {
-    BB = Worklist.back();
-    Worklist.pop_back();
+  do {
+    BB = Worklist.pop_back_val();
     
     if (!Reachable.insert(BB))
       continue;
@@ -150,7 +149,7 @@ static bool MarkAliveBlocks(BasicBlock *BB,
     Changed |= ConstantFoldTerminator(BB);
     for (succ_iterator SI = succ_begin(BB), SE = succ_end(BB); SI != SE; ++SI)
       Worklist.push_back(*SI);
-  }
+  } while (!Worklist.empty());
   return Changed;
 }
 
diff --git a/lib/Transforms/Utils/CloneLoop.cpp b/lib/Transforms/Utils/CloneLoop.cpp
index 7e000a1a75..38928dc7cc 100644
--- a/lib/Transforms/Utils/CloneLoop.cpp
+++ b/lib/Transforms/Utils/CloneLoop.cpp
@@ -91,7 +91,7 @@ Loop *llvm::CloneLoop(Loop *OrigL, LPPassManager  *LPM, LoopInfo *LI,
 
 
   Loop *NewParentLoop = NULL;
-  while (!LoopNest.empty()) {
+  do {
     Loop *L = LoopNest.pop_back_val();
     Loop *NewLoop = new Loop();
 
@@ -123,7 +123,7 @@ Loop *llvm::CloneLoop(Loop *OrigL, LPPassManager  *LPM, LoopInfo *LI,
     // Process sub loops
     for (Loop::iterator I = L->begin(), E = L->end(); I != E; ++I)
       LoopNest.push_back(*I);
-  }
+  } while (!LoopNest.empty());
 
   // Remap instructions to reference operands from ValueMap.
   for(SmallVector<BasicBlock *, 16>::iterator NBItr = NewBlocks.begin(), 
diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp
index 27d9a06bfc..30fe802513 100644
--- a/lib/Transforms/Utils/Local.cpp
+++ b/lib/Transforms/Utils/Local.cpp
@@ -278,7 +278,7 @@ bool llvm::RecursivelyDeleteTriviallyDeadInstructions(Value *V) {
   SmallVector<Instruction*, 16> DeadInsts;
   DeadInsts.push_back(I);
   
-  while (!DeadInsts.empty()) {
+  do {
     I = DeadInsts.pop_back_val();
 
     // Null out all of the instruction's operands to see if any operand becomes
@@ -298,7 +298,7 @@ bool llvm::RecursivelyDeleteTriviallyDeadInstructions(Value *V) {
     }
     
     I->eraseFromParent();
-  }
+  } while (!DeadInsts.empty());
 
   return true;
 }
diff --git a/lib/Transforms/Utils/PromoteMemoryToRegister.cpp b/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
index 846e432a7d..baaa130df6 100644
--- a/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
+++ b/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
@@ -448,13 +448,13 @@ void PromoteMem2Reg::run() {
   //
   std::vector<RenamePassData> RenamePassWorkList;
   RenamePassWorkList.push_back(RenamePassData(F.begin(), 0, Values));
-  while (!RenamePassWorkList.empty()) {
+  do {
     RenamePassData RPD;
     RPD.swap(RenamePassWorkList.back());
     RenamePassWorkList.pop_back();
     // RenamePass may add new worklist entries.
     RenamePass(RPD.BB, RPD.Pred, RPD.Values, RenamePassWorkList);
-  }
+  } while (!RenamePassWorkList.empty());
   
   // The renamer uses the Visited set to avoid infinite loops.  Clear it now.
   Visited.clear();