From: Chris Lattner <sabre@nondot.org>
Date: Sun, 5 Mar 2006 19:53:55 +0000 (+0000)
Subject: Reinstate this now that the offending opposite xform has been removed.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=cac7059d0f8e6e1be5d4001eb942e23780af2300;p=oota-llvm.git

Reinstate this now that the offending opposite xform has been removed.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26548 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index bf4b39db07b..1e05d583e83 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -1454,6 +1454,13 @@ SDOperand DAGCombiner::visitSHL(SDNode *N) {
   if (N1C && N0.getOpcode() == ISD::SRA && N1 == N0.getOperand(1))
     return DAG.getNode(ISD::AND, VT, N0.getOperand(0),
                        DAG.getConstant(~0ULL << N1C->getValue(), VT));
+  // fold (shl (add x, c1), c2) -> (add (shl x, c2), c1<<c2)
+  if (N1C && N0.getOpcode() == ISD::ADD && N0.Val->hasOneUse() && 
+      isa<ConstantSDNode>(N0.getOperand(1))) {
+    return DAG.getNode(ISD::ADD, VT, 
+                       DAG.getNode(ISD::SHL, VT, N0.getOperand(0), N1),
+                       DAG.getNode(ISD::SHL, VT, N0.getOperand(1), N1));
+  }
   return SDOperand();
 }