[llvm] r258644 - Tidied up TRUNC combine code. NFC.

[Simon Pilgrim via llvm-commits]

Author: rksimon
Date: Sat Jan 23 15:50:40 2016
New Revision: 258644

URL: http://llvm.org/viewvc/llvm-project?rev=258644&view=rev
Log:
Tidied up TRUNC combine code. NFC.

Make use of DAG.getBitcast and use clang-format to reduce number of lines (and make it more readable).

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

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp?rev=258644&r1=258643&r2=258644&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp Sat Jan 23 15:50:40 2016
@@ -7020,12 +7020,11 @@ SDValue DAGCombiner::visitTRUNCATE(SDNod
   if (N0.getOpcode() == ISD::ZERO_EXTEND ||
       N0.getOpcode() == ISD::SIGN_EXTEND ||
       N0.getOpcode() == ISD::ANY_EXTEND) {
+    // if the source is smaller than the dest, we still need an extend.
     if (N0.getOperand(0).getValueType().bitsLT(VT))
-      // if the source is smaller than the dest, we still need an extend
-      return DAG.getNode(N0.getOpcode(), SDLoc(N), VT,
-                         N0.getOperand(0));
+      return DAG.getNode(N0.getOpcode(), SDLoc(N), VT, N0.getOperand(0));
+    // if the source is larger than the dest, than we just need the truncate.
     if (N0.getOperand(0).getValueType().bitsGT(VT))
-      // if the source is larger than the dest, than we just need the truncate
       return DAG.getNode(ISD::TRUNCATE, SDLoc(N), VT, N0.getOperand(0));
     // if the source and dest are the same type, we can drop both the extend
     // and the truncate.
@@ -7061,12 +7060,9 @@ SDValue DAGCombiner::visitTRUNCATE(SDNod
       EVT IndexTy = TLI.getVectorIdxTy(DAG.getDataLayout());
       int Index = isLE ? (Elt*SizeRatio) : (Elt*SizeRatio + (SizeRatio-1));
 
-      SDValue V = DAG.getNode(ISD::BITCAST, SDLoc(N),
-                              NVT, N0.getOperand(0));
-
       SDLoc DL(N);
-      return DAG.getNode(ISD::EXTRACT_VECTOR_ELT,
-                         DL, TrTy, V,
+      return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, TrTy,
+                         DAG.getBitcast(NVT, N0.getOperand(0)),
                          DAG.getConstant(Index, DL, IndexTy));
     }
   }