Improve EXTRACT_VECTOR_ELT patch based on comments from Duncan

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95012 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 6729a93fd7169fb47b0aafcd46caab108fd8aba8..10487dabd28b2a63fcad71f493adee1826dc93ef 100644 (file)
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -5411,10 +5411,7 @@ SDValue DAGCombiner::visitEXTRACT_VECTOR_ELT(SDNode *N) {
    EVT NVT = N->getValueType(0);
    if (InOp.getValueType() != NVT) {
      assert(InOp.getValueType().isInteger() && NVT.isInteger());
-     if (NVT.getSizeInBits() > InOp.getValueType().getSizeInBits())
-       return DAG.getNode(ISD::SIGN_EXTEND, InVec.getDebugLoc(), NVT, InOp);
-     else
-       return DAG.getNode(ISD::TRUNCATE, InVec.getDebugLoc(), NVT, InOp);
+     return DAG.getSExtOrTrunc(InOp, InVec.getDebugLoc(), NVT);
    }
    return InOp;
  }

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 2e92f8f1fd168aaf418a585ac692e5cc694db84a..5315b2126019d327fca057ad938f16cc93d2d4c9 100644 (file)
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -2764,13 +2764,16 @@ SDValue SelectionDAG::getNode(unsigned Opcode, DebugLoc DL, EVT VT,
     // EXTRACT_VECTOR_ELT of INSERT_VECTOR_ELT is often formed when vector
     // operations are lowered to scalars.
     if (N1.getOpcode() == ISD::INSERT_VECTOR_ELT) {
-      // If the indices are the same, return the inserted element.
-      if (N1.getOperand(2) == N2 && VT == N1.getOperand(1).getValueType())
-        return N1.getOperand(1);
-      // If the indices are known different, extract the element from
+      // If the indices are the same, return the inserted element else
+      // if the indices are known different, extract the element from
       // the original vector.
-      else if (isa<ConstantSDNode>(N1.getOperand(2)) &&
-               isa<ConstantSDNode>(N2))
+      if (N1.getOperand(2) == N2) {
+        if (VT == N1.getOperand(1).getValueType())
+          return N1.getOperand(1);
+        else
+          return getSExtOrTrunc(N1.getOperand(1), DL, VT);
+      } else if (isa<ConstantSDNode>(N1.getOperand(2)) &&
+                 isa<ConstantSDNode>(N2))
         return getNode(ISD::EXTRACT_VECTOR_ELT, DL, VT, N1.getOperand(0), N2);
     }
     break;