Fix some problems where the verifier would crash on invalid input instead of

reporting the problem and exiting.

llvm-svn: 20302

2 files changed, 7 insertions, 3 deletions

diff --git a/llvm/lib/VMCore/AsmWriter.cpp b/llvm/lib/VMCore/AsmWriter.cpp
index 5406c833a22..b42ccc18471 100644
--- a/llvm/lib/VMCore/AsmWriter.cpp
+++ b/llvm/lib/VMCore/AsmWriter.cpp
@@ -755,9 +755,12 @@ std::ostream &AssemblyWriter::printTypeAtLeastOneLevel(const Type *Ty) {
 
 void AssemblyWriter::writeOperand(const Value *Operand, bool PrintType, 
                                   bool PrintName) {
-  assert(Operand != 0 && "Illegal Operand");
-  if (PrintType) { Out << ' '; printType(Operand->getType()); }
-  WriteAsOperandInternal(Out, Operand, PrintName, TypeNames, &Machine);
+  if (Operand != 0) {
+    if (PrintType) { Out << ' '; printType(Operand->getType()); }
+    WriteAsOperandInternal(Out, Operand, PrintName, TypeNames, &Machine);
+  } else {
+    Out << "<null operand!>";
+  }
 }
 
 
diff --git a/llvm/lib/VMCore/Verifier.cpp b/llvm/lib/VMCore/Verifier.cpp
index ad1074d8d33..4fae3b72d11 100644
--- a/llvm/lib/VMCore/Verifier.cpp
+++ b/llvm/lib/VMCore/Verifier.cpp
@@ -592,6 +592,7 @@ void Verifier::visitInstruction(Instruction &I) {
   for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i) {
     // Check to make sure that the "address of" an intrinsic function is never
     // taken.
+    Assert1(I.getOperand(i) != 0, "Instruction has null operand!", &I);
     if (Function *F = dyn_cast<Function>(I.getOperand(i))) {
       Assert1(!F->isIntrinsic() || (i == 0 && isa<CallInst>(I)),
               "Cannot take the address of an intrinsic!", &I);