Handle post dominance correctly in the case where blocks do not have a path to

the exit node.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4038 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2002-10-04 14:50:20 +00:00
parent 4e4caeffbd
commit 7d821db958

View File

@ -59,6 +59,18 @@ bool PostDominatorSet::runOnFunction(Function &F) {
if (PredSet.size())
set_intersect(WorkingSet, PredSet);
}
} else if (BB != Root) {
// If this isn't the root basic block and it has no successors, it must
// be an non-returning block. Fib a bit by saying that the root node
// postdominates this unreachable node. This isn't exactly true,
// because there is no path from this node to the root node, but it is
// sorta true because any paths to the exit node would have to go
// through this node.
//
// This allows for postdominator properties to be built for code that
// doesn't return in a reasonable manner.
//
WorkingSet = Doms[Root];
}
WorkingSet.insert(BB); // A block always dominates itself