Don't create indexed load / store with zero offset!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36716 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 5977e88ee135092355f919d5745925bf2bf5dd63..8396e45be309d652609d97fd3cd52cfc339bcba8 100644 (file)
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -3110,6 +3110,10 @@ bool DAGCombiner::CombineToPreIndexedLoadStore(SDNode *N) {
   ISD::MemIndexedMode AM = ISD::UNINDEXED;
   if (!TLI.getPreIndexedAddressParts(N, BasePtr, Offset, AM, DAG))
     return false;
+  // Don't create a indexed load / store with zero offset.
+  if (isa<ConstantSDNode>(Offset) &&
+      cast<ConstantSDNode>(Offset)->getValue() == 0)
+    return false;
   
   // Try turning it into a pre-indexed load / store except when:
   // 1) The base is a frame index.
@@ -3239,6 +3243,10 @@ bool DAGCombiner::CombineToPostIndexedLoadStore(SDNode *N) {
         std::swap(BasePtr, Offset);
       if (Ptr != BasePtr)
         continue;
+      // Don't create a indexed load / store with zero offset.
+      if (isa<ConstantSDNode>(Offset) &&
+          cast<ConstantSDNode>(Offset)->getValue() == 0)
+        continue;
 
       // Try turning it into a post-indexed load / store except when
       // 1) All uses are load / store ops that use it as base ptr.