Refactor creation of overflow result tuples in InstCombineCalls.

Extract the creation of overflow result tuples in a separate function. NFC.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224006 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/InstCombine/InstCombine.h

@@ -331,6 +331,20 @@ public:
     return &I;
   }
 
+  /// Creates a result tuple for an overflow intrinsic \p II with a given
+  /// \p Result and a constant \p Overflow value. If \p ReUseName is true the
+  /// \p Result's name is taken from \p II.
+  Instruction *CreateOverflowTuple(IntrinsicInst *II, Value *Result,
+                                    bool Overflow, bool ReUseName = true) {
+    if (ReUseName)
+      Result->takeName(II);
+    Constant *V[] = { UndefValue::get(Result->getType()),
+                      Overflow ? Builder->getTrue() : Builder->getFalse() };
+    StructType *ST = cast<StructType>(II->getType());
+    Constant *Struct = ConstantStruct::get(ST, V);
+    return InsertValueInst::Create(Struct, Result, 0);
+  }
+        
   // EraseInstFromFunction - When dealing with an instruction that has side
   // effects or produces a void value, we can't rely on DCE to delete the
   // instruction.  Instead, visit methods should return the value returned by