Index: include/llvm/IR/Operator.h
===================================================================
--- include/llvm/IR/Operator.h
+++ include/llvm/IR/Operator.h
@@ -425,6 +425,16 @@
     }
     return true;
   }
+  
+  /// hasAConstantIndex - Returns true if any of the indices of this GEP are
+  /// constant integers.
+  bool hasAConstantIndex() const {
+    for (const_op_iterator I = idx_begin(), E = idx_end(); I != E; ++I) {
+      if (isa<ConstantInt>(I))
+        return true;
+    }
+    return false;
+  }
 
   /// hasAllConstantIndices - Return true if all of the indices of this GEP are
   /// constant integers.  If so, the result pointer and the first operand have
Index: lib/Transforms/InstCombine/InstructionCombining.cpp
===================================================================
--- lib/Transforms/InstCombine/InstructionCombining.cpp
+++ lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -842,6 +842,7 @@
   if (GEP.hasAllZeroIndices() && !Src.hasAllZeroIndices() &&
       !Src.hasOneUse())
     return false;
+  
   return true;
 }
 
@@ -1348,6 +1349,11 @@
         // normalized.
         if (SO1->getType() != GO1->getType())
           return nullptr;
+          
+        // Is it worth summing the offsets?
+        if (!isa<ConstantInt>(SO1))
+        	return nullptr;
+        
         Sum = Builder->CreateAdd(SO1, GO1, PtrOp->getName()+".sum");
       }