[llvm] r266100 - [CodeGen] Remove constant-folding dead code. NFC.

[Ahmed Bougacha via llvm-commits]

Author: ab
Date: Tue Apr 12 13:15:39 2016
New Revision: 266100

URL: http://llvm.org/viewvc/llvm-project?rev=266100&view=rev
Log:
[CodeGen] Remove constant-folding dead code. NFC.

This code was specific to vector operations with scalar operands:
all the opcodes in FoldValue (via FoldConstantArithmetic) can't
match those criteria.

Replace it with an assert if that ever changes: at that point,
we might need to add back a splat BUILD_VECTOR.

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp?rev=266100&r1=266099&r2=266100&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp Tue Apr 12 13:15:39 2016
@@ -3295,18 +3295,10 @@ SDValue SelectionDAG::FoldConstantArithm
   // Handle the case of two scalars.
   if (const ConstantSDNode *Scalar1 = dyn_cast<ConstantSDNode>(Cst1)) {
     if (const ConstantSDNode *Scalar2 = dyn_cast<ConstantSDNode>(Cst2)) {
-      if (SDValue Folded =
-          FoldConstantArithmetic(Opcode, DL, VT, Scalar1, Scalar2)) {
-        if (!VT.isVector())
-          return Folded;
-        SmallVector<SDValue, 4> Outputs;
-        // We may have a vector type but a scalar result. Create a splat.
-        Outputs.resize(VT.getVectorNumElements(), Outputs.back());
-        // Build a big vector out of the scalar elements we generated.
-        return getNode(ISD::BUILD_VECTOR, SDLoc(), VT, Outputs);
-      } else {
-        return SDValue();
-      }
+      SDValue Folded = FoldConstantArithmetic(Opcode, DL, VT, Scalar1, Scalar2);
+      assert((!Folded || !VT.isVector()) &&
+             "Can't fold vectors ops with scalar operands");
+      return Folded;
     }
   }