Revert "merge consecutive stores of extracted vector elements"

This reverts commit r224611. This change causes crashes
in X86 DAG->DAG Instruction Selection.

llvm-svn: 225031

2 files changed, 4 insertions, 108 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 5134066688d..5a6ea8e6810 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -9499,14 +9499,11 @@ bool DAGCombiner::MergeConsecutiveStores(StoreSDNode* St) {
     return false;
 
   // Perform an early exit check. Do not bother looking at stored values that
-  // are not constants, loads, or extracted vector elements.
+  // are not constants or loads.
   SDValue StoredVal = St->getValue();
   bool IsLoadSrc = isa<LoadSDNode>(StoredVal);
-  bool IsConstantSrc = isa<ConstantSDNode>(StoredVal) ||
-                       isa<ConstantFPSDNode>(StoredVal);
-  bool IsExtractVecEltSrc = (StoredVal.getOpcode() == ISD::EXTRACT_VECTOR_ELT);
-   
-  if (!IsConstantSrc && !IsLoadSrc && !IsExtractVecEltSrc)
+  if (!isa<ConstantSDNode>(StoredVal) && !isa<ConstantFPSDNode>(StoredVal) &&
+      !IsLoadSrc)
     return false;
 
   // Only look at ends of store sequences.
@@ -9648,7 +9645,7 @@ bool DAGCombiner::MergeConsecutiveStores(StoreSDNode* St) {
   LSBaseSDNode *FirstInChain = StoreNodes[0].MemNode;
 
   // Store the constants into memory as one consecutive store.
-  if (IsConstantSrc) {
+  if (!IsLoadSrc) {
     unsigned LastLegalType = 0;
     unsigned LastLegalVectorType = 0;
     bool NonZero = false;
@@ -9778,74 +9775,6 @@ bool DAGCombiner::MergeConsecutiveStores(StoreSDNode* St) {
     return true;
   }
 
-  // When extracting multiple vector elements, try to store them
-  // in one vector store rather than a sequence of scalar stores.
-  if (IsExtractVecEltSrc) {
-    unsigned NumElem = 0;
-    for (unsigned i = 0; i < LastConsecutiveStore + 1; ++i) {
-      // Find a legal type for the vector store.
-      EVT Ty = EVT::getVectorVT(*DAG.getContext(), MemVT, i+1);
-      if (TLI.isTypeLegal(Ty))
-        NumElem = i + 1;
-    }
-
-    // Make sure we have a legal type and something to merge.
-    if (NumElem < 2)
-      return false;
-
-    unsigned EarliestNodeUsed = 0;
-    for (unsigned i=0; i < NumElem; ++i) {
-      // Find a chain for the new wide-store operand. Notice that some
-      // of the store nodes that we found may not be selected for inclusion
-      // in the wide store. The chain we use needs to be the chain of the
-      // earliest store node which is *used* and replaced by the wide store.
-      if (StoreNodes[i].SequenceNum > StoreNodes[EarliestNodeUsed].SequenceNum)
-        EarliestNodeUsed = i;
-    }
-   
-    // The earliest Node in the DAG.
-    LSBaseSDNode *EarliestOp = StoreNodes[EarliestNodeUsed].MemNode;
-    SDLoc DL(StoreNodes[0].MemNode);
-   
-    SDValue StoredVal;
-
-    // Find a legal type for the vector store.
-    EVT Ty = EVT::getVectorVT(*DAG.getContext(), MemVT, NumElem);
-
-    SmallVector<SDValue, 8> Ops;
-    for (unsigned i = 0; i < NumElem ; ++i) {
-      StoreSDNode *St = cast<StoreSDNode>(StoreNodes[i].MemNode);
-      SDValue Val = St->getValue();
-      // All of the operands of a BUILD_VECTOR must have the same type.
-      if (Val.getValueType() != MemVT)
-        return false;
-      Ops.push_back(Val);
-    }
-   
-    // Build the extracted vector elements back into a vector.
-    StoredVal = DAG.getNode(ISD::BUILD_VECTOR, DL, Ty, Ops);
-
-    SDValue NewStore = DAG.getStore(EarliestOp->getChain(), DL, StoredVal,
-                                    FirstInChain->getBasePtr(),
-                                    FirstInChain->getPointerInfo(),
-                                    false, false,
-                                    FirstInChain->getAlignment());
-
-    // Replace the first store with the new store
-    CombineTo(EarliestOp, NewStore);
-    // Erase all other stores.
-    for (unsigned i = 0; i < NumElem ; ++i) {
-      if (StoreNodes[i].MemNode == EarliestOp)
-        continue;
-      StoreSDNode *St = cast<StoreSDNode>(StoreNodes[i].MemNode);
-      while (!St->use_empty())
-        DAG.ReplaceAllUsesWith(SDValue(St, 0), St->getChain());
-      deleteAndRecombine(St);
-    }
-
-    return true;
-  }
-
   // Below we handle the case of multiple consecutive stores that
   // come from multiple consecutive loads. We merge them into a single
   // wide load and a single wide store.
diff --git a/llvm/test/CodeGen/X86/MergeConsecutiveStores.ll b/llvm/test/CodeGen/X86/MergeConsecutiveStores.ll
index cf984a4f3a9..dfdaea523fd 100644
--- a/llvm/test/CodeGen/X86/MergeConsecutiveStores.ll
+++ b/llvm/test/CodeGen/X86/MergeConsecutiveStores.ll
@@ -434,36 +434,3 @@ define void @loadStoreBaseIndexOffsetSextNoSex(i8* %a, i8* %b, i8* %c, i32 %n) {
 ; <label>:14
   ret void
 }
-
-define void @merge_vec_element_store(<8 x float> %v, float* %ptr) {
-  %vecext0 = extractelement <8 x float> %v, i32 0
-  %vecext1 = extractelement <8 x float> %v, i32 1
-  %vecext2 = extractelement <8 x float> %v, i32 2
-  %vecext3 = extractelement <8 x float> %v, i32 3
-  %vecext4 = extractelement <8 x float> %v, i32 4
-  %vecext5 = extractelement <8 x float> %v, i32 5
-  %vecext6 = extractelement <8 x float> %v, i32 6
-  %vecext7 = extractelement <8 x float> %v, i32 7
-  %arrayidx1 = getelementptr inbounds float* %ptr, i64 1
-  %arrayidx2 = getelementptr inbounds float* %ptr, i64 2
-  %arrayidx3 = getelementptr inbounds float* %ptr, i64 3
-  %arrayidx4 = getelementptr inbounds float* %ptr, i64 4
-  %arrayidx5 = getelementptr inbounds float* %ptr, i64 5
-  %arrayidx6 = getelementptr inbounds float* %ptr, i64 6
-  %arrayidx7 = getelementptr inbounds float* %ptr, i64 7
-  store float %vecext0, float* %ptr, align 4
-  store float %vecext1, float* %arrayidx1, align 4
-  store float %vecext2, float* %arrayidx2, align 4
-  store float %vecext3, float* %arrayidx3, align 4
-  store float %vecext4, float* %arrayidx4, align 4
-  store float %vecext5, float* %arrayidx5, align 4
-  store float %vecext6, float* %arrayidx6, align 4
-  store float %vecext7, float* %arrayidx7, align 4
-  ret void
-
-; CHECK-LABEL: merge_vec_element_store
-; CHECK: vmovups
-; CHECK-NEXT: vzeroupper
-; CHECK-NEXT: retq
-}
-