Avoid moving iterators when the previous block was just visited.

[oota-llvm.git] / lib / CodeGen / StackProtector.cpp

diff --git a/lib/CodeGen/StackProtector.cpp b/lib/CodeGen/StackProtector.cpp
index 1a588e25d6e3fa2bc9dff99c89edc348e25d2875..f0a44abaf5cda1b4d4267752a46fc73f18a2a492 100644 (file)
--- a/lib/CodeGen/StackProtector.cpp
+++ b/lib/CodeGen/StackProtector.cpp
@@ -153,7 +153,6 @@ bool StackProtector::InsertStackProtectors() {
 
   for (Function::iterator I = F->begin(), E = F->end(); I != E; ) {
     BasicBlock *BB = I++;
-
     ReturnInst *RI = dyn_cast<ReturnInst>(BB->getTerminator());
     if (!RI) continue;
 
@@ -191,8 +190,6 @@ bool StackProtector::InsertStackProtectors() {
 
       // Create the basic block to jump to when the guard check fails.
       FailBB = CreateFailBB();
-      if (DT)
-        FailBBDom = DT->isReachableFromEntry(BB) ? BB : 0;
     }
 
     // For each block with a return instruction, convert this:
@@ -219,10 +216,10 @@ bool StackProtector::InsertStackProtectors() {
 
     // Split the basic block before the return instruction.
     BasicBlock *NewBB = BB->splitBasicBlock(RI, "SP_return");
+
     if (DT && DT->isReachableFromEntry(BB)) {
       DT->addNewBlock(NewBB, BB);
-      if (FailBBDom)
-        FailBBDom = DT->findNearestCommonDominator(FailBBDom, BB);
+      FailBBDom = FailBBDom ? DT->findNearestCommonDominator(FailBBDom, BB) :BB;
     }
 
     // Remove default branch instruction to the new BB.