R600/SI: Check for empty stack in SIAnnotateControlFlow::isTopOfStack

Fixes assertion failure in newly added lit test. Might just be a bandaid that
needs to be revisited.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175139 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Michel Danzer 2013-02-14 08:00:33 +00:00
parent d4addbe78a
commit c556fcc153

View File

@ -147,7 +147,7 @@ bool SIAnnotateControlFlow::doInitialization(Module &M) {
/// \brief Is BB the last block saved on the stack ?
bool SIAnnotateControlFlow::isTopOfStack(BasicBlock *BB) {
return Stack.back().first == BB;
return !Stack.empty() && Stack.back().first == BB;
}
/// \brief Pop the last saved value from the control flow stack