Until we have a dag combiner, promote using zextload's instead of extloads.

This gives the optimizer a bit of information about the top-part of the
value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21205 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 1fcaa723e2c4788265ce73c85cf2b4d75d6c4914..b551eebf7cb0296536efa4bd8e2750c3922c7562 100644 (file)
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -1355,7 +1355,8 @@ SDOperand SelectionDAGLegalize::PromoteOp(SDOperand Op) {
   case ISD::LOAD:
     Tmp1 = LegalizeOp(Node->getOperand(0));   // Legalize the chain.
     Tmp2 = LegalizeOp(Node->getOperand(1));   // Legalize the pointer.
-    Result = DAG.getNode(ISD::EXTLOAD, NVT, Tmp1, Tmp2, VT);
+    // FIXME: When the DAG combiner exists, change this to use EXTLOAD!
+    Result = DAG.getNode(ISD::ZEXTLOAD, NVT, Tmp1, Tmp2, VT);
 
     // Remember that we legalized the chain.
     AddLegalizedOperand(Op.getValue(1), Result.getValue(1));