diff --git a/llvm/include/llvm/IR/Constants.h b/llvm/include/llvm/IR/Constants.h
--- a/llvm/include/llvm/IR/Constants.h
+++ b/llvm/include/llvm/IR/Constants.h
@@ -1250,7 +1250,7 @@
   /// which would take a ConstantExpr parameter, but that would have spread
   /// implementation details of ConstantExpr outside of Constants.cpp, which
   /// would make it harder to remove ConstantExprs altogether.
-  Instruction *getAsInstruction();
+  Instruction *getAsInstruction() const;
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Value *V) {
diff --git a/llvm/lib/IR/Constants.cpp b/llvm/lib/IR/Constants.cpp
--- a/llvm/lib/IR/Constants.cpp
+++ b/llvm/lib/IR/Constants.cpp
@@ -3004,7 +3004,7 @@
       NewOps, this, From, To, NumUpdated, OperandNo);
 }
 
-Instruction *ConstantExpr::getAsInstruction() {
+Instruction *ConstantExpr::getAsInstruction() const {
   SmallVector<Value *, 4> ValueOperands(op_begin(), op_end());
   ArrayRef<Value*> Ops(ValueOperands);