diff --git a/libIRDB/include/util/insn_preds.hpp b/libIRDB/include/util/insn_preds.hpp
index 0bd7fc2dfbfae7b06f165f719336cc236d2ba0fb..96a5f561fb5b2f4a99add1920e09194766983db6 100644
--- a/libIRDB/include/util/insn_preds.hpp
+++ b/libIRDB/include/util/insn_preds.hpp
@@ -31,6 +31,10 @@ class InstructionPredecessors_t
 	InstructionPredecessors_t(const FileIR_t* f=NULL) {Init(); if(f) AddFile(f);}
 	virtual void AddFile(const FileIR_t* );
 
+	InstructionSet_t& operator[] (const Instruction_t* i)  
+		{
+			return pred_map[i];
+		}
 	const InstructionSet_t& operator[] (const Instruction_t* i)  const
 		{ 
 			PredMap_t::const_iterator it=pred_map.find(i);