PHI nodes are not allowed to exist with zero incoming values, check that
there aren't any like this.
llvm-svn: 4044
diff --git a/llvm/lib/VMCore/Verifier.cpp b/llvm/lib/VMCore/Verifier.cpp
index 51e0d2d..1663ddf 100644
--- a/llvm/lib/VMCore/Verifier.cpp
+++ b/llvm/lib/VMCore/Verifier.cpp
@@ -17,6 +17,7 @@
// * Only phi nodes can be self referential: 'add int %0, %0 ; <int>:0' is bad
// * PHI nodes must have an entry for each predecessor, with no extras.
// * PHI nodes must be the first thing in a basic block, all grouped together
+// * PHI nodes must have at least one entry
// * All basic blocks should only end with terminator insts, not contain them
// * The entry node to a function must not have predecessors
// * All Instructions must be embeded into a basic block
@@ -258,6 +259,12 @@
"PHI nodes not grouped at top of basic block!",
&PN, PN.getParent());
+ // Ensure that PHI nodes have at least one entry!
+ Assert1(PN.getNumIncomingValues() != 0,
+ "PHI nodes must have at least one entry. If the block is dead, "
+ "the PHI should be removed!",
+ &PN);
+
std::vector<BasicBlock*> Preds(pred_begin(PN.getParent()),
pred_end(PN.getParent()));
// Loop over all of the incoming values, make sure that there are