revert r25736

src/compiler/instruction.cc

Index: src/compiler/instruction.cc
diff --git a/src/compiler/instruction.cc b/src/compiler/instruction.cc
index 827cacf665107f13b0f49315c02f713a8fa5277c..6cab71f16bc590929d160a1de092d3c3ff57e233 100644
--- a/src/compiler/instruction.cc
+++ b/src/compiler/instruction.cc
@@ -15,6 +15,8 @@ std::ostream& operator<<(std::ostream& os,
   const InstructionOperand& op = *printable.op_;
   const RegisterConfiguration* conf = printable.register_configuration_;
   switch (op.kind()) {
+    case InstructionOperand::INVALID:
+      return os << "(0)";
     case InstructionOperand::UNALLOCATED: {
       const UnallocatedOperand* unalloc = UnallocatedOperand::cast(&op);
       os << "v" << unalloc->virtual_register();