From b37b80ce4669c41dcebaeb227b15f552b2c24210 Mon Sep 17 00:00:00 2001
From: Evan Cheng <evan.cheng@apple.com>
Date: Fri, 23 Mar 2007 20:55:21 +0000
Subject: [PATCH] Also replace uses of SRL if that's also folded during
 ReduceLoadWidth().

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35286 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 1aea2ed35f5..df951a51bb2 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -2279,6 +2279,7 @@ SDOperand DAGCombiner::ReduceLoadWidth(SDNode *N) {
 
   unsigned EVTBits = MVT::getSizeInBits(EVT);
   unsigned ShAmt = 0;
+  bool CombineSRL =  false;
   if (N0.getOpcode() == ISD::SRL && N0.hasOneUse()) {
     if (ConstantSDNode *N01 = dyn_cast<ConstantSDNode>(N0.getOperand(1))) {
       ShAmt = N01->getValue();
@@ -2288,6 +2289,7 @@ SDOperand DAGCombiner::ReduceLoadWidth(SDNode *N) {
         if (MVT::getSizeInBits(N0.getValueType()) <= EVTBits)
           return SDOperand();
         ShAmt /= 8;
+        CombineSRL = true;
       }
     }
   }
@@ -2317,7 +2319,12 @@ SDOperand DAGCombiner::ReduceLoadWidth(SDNode *N) {
       : DAG.getExtLoad(ExtType, VT, LN0->getChain(), NewPtr,
                        LN0->getSrcValue(), LN0->getSrcValueOffset(), EVT);
     AddToWorkList(N);
-    CombineTo(N0.Val, Load, Load.getValue(1));
+    if (CombineSRL) {
+      std::vector<SDNode*> NowDead;
+      DAG.ReplaceAllUsesOfValueWith(N0.getValue(1), Load.getValue(1), NowDead);
+      CombineTo(N->getOperand(0).Val, Load);
+    } else
+      CombineTo(N0.Val, Load, Load.getValue(1));
     if (ShAmt)
       return DAG.getNode(N->getOpcode(), VT, Load);
     return SDOperand(N, 0);   // Return N so it doesn't get rechecked!