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
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 5134066..5a6ea8e 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -9499,14 +9499,11 @@
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 @@
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 @@
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.