- Make sure that we don't over-increment the iterator when going through the
basic blocks.
- Minor code clean-up.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@59002 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/StackProtector.cpp b/lib/CodeGen/StackProtector.cpp
index 19fd45c..386c7cd 100644
--- a/lib/CodeGen/StackProtector.cpp
+++ b/lib/CodeGen/StackProtector.cpp
@@ -123,14 +123,11 @@
AllocaInst *AI = 0; // Place on stack that stores the stack guard.
Constant *StackGuardVar = 0; // The stack guard variable.
- for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
+ for (Function::iterator I = F->begin(), E = F->end(); I != E; ) {
BasicBlock *BB = I;
- if (isa<ReturnInst>(BB->getTerminator())) {
+ if (ReturnInst *RI = dyn_cast<ReturnInst>(BB->getTerminator())) {
if (!FailBB) {
- // Create the basic block to jump to when the guard check fails.
- FailBB = CreateFailBB();
-
// Insert code into the entry block that stores the __stack_chk_guard
// variable onto the stack.
PointerType *PtrTy = PointerType::getUnqual(Type::Int8Ty);
@@ -146,11 +143,13 @@
CallInst::
Create(Intrinsic::getDeclaration(M, Intrinsic::stackprotector_create),
&Args[0], array_endof(Args), "", InsPt);
+
+ // Create the basic block to jump to when the guard check fails.
+ FailBB = CreateFailBB();
}
- ReturnInst *RI = cast<ReturnInst>(BB->getTerminator());
Function::iterator InsPt = BB; ++InsPt; // Insertion point for new BB.
- ++I;
+ ++I; // Skip to the next block so that we don't resplit the return block.
// Split the basic block before the return instruction.
BasicBlock *NewBB = BB->splitBasicBlock(RI, "SP_return");
@@ -167,6 +166,8 @@
AI, "", BB);
ICmpInst *Cmp = new ICmpInst(CmpInst::ICMP_EQ, CI, LI1, "", BB);
BranchInst::Create(NewBB, FailBB, Cmp, BB);
+ } else {
+ ++I;
}
}