static SDValue PerformSTORECombine(SDNode *N,
TargetLowering::DAGCombinerInfo &DCI) {
StoreSDNode *St = cast<StoreSDNode>(N);
+ if (St->isVolatile())
+ return SDValue();
+
+ // Optimize trunc store (of multiple scalars) to shuffle and store. First,
+ // pack all of the elements in one place. Next, store to memory in fewer
+ // chunks.
SDValue StVal = St->getValue();
- if (!ISD::isNormalStore(St) || St->isVolatile())
+ EVT VT = StVal.getValueType();
+ if (St->isTruncatingStore() && VT.isVector()) {
+ SelectionDAG &DAG = DCI.DAG;
+ const TargetLowering &TLI = DAG.getTargetLoweringInfo();
+ EVT StVT = St->getMemoryVT();
+ unsigned NumElems = VT.getVectorNumElements();
+ assert(StVT != VT && "Cannot truncate to the same type");
+ unsigned FromEltSz = VT.getVectorElementType().getSizeInBits();
+ unsigned ToEltSz = StVT.getVectorElementType().getSizeInBits();
+
+ // From, To sizes and ElemCount must be pow of two
+ if (!isPowerOf2_32(NumElems * FromEltSz * ToEltSz)) return SDValue();
+
+ // We are going to use the original vector elt for storing.
+ // Accumulated smaller vector elements must be a multiple of the store size.
+ if (0 != (NumElems * FromEltSz) % ToEltSz) return SDValue();
+
+ unsigned SizeRatio = FromEltSz / ToEltSz;
+ assert(SizeRatio * NumElems * ToEltSz == VT.getSizeInBits());
+
+ // Create a type on which we perform the shuffle.
+ EVT WideVecVT = EVT::getVectorVT(*DAG.getContext(), StVT.getScalarType(),
+ NumElems*SizeRatio);
+ assert(WideVecVT.getSizeInBits() == VT.getSizeInBits());
+
+ DebugLoc DL = St->getDebugLoc();
+ SDValue WideVec = DAG.getNode(ISD::BITCAST, DL, WideVecVT, StVal);
+ SmallVector<int, 8> ShuffleVec(NumElems * SizeRatio, -1);
+ for (unsigned i = 0; i < NumElems; ++i) ShuffleVec[i] = i * SizeRatio;
+
+ // Can't shuffle using an illegal type.
+ if (!TLI.isTypeLegal(WideVecVT)) return SDValue();
+
+ SDValue Shuff = DAG.getVectorShuffle(WideVecVT, DL, WideVec,
+ DAG.getUNDEF(WideVec.getValueType()),
+ ShuffleVec.data());
+ // At this point all of the data is stored at the bottom of the
+ // register. We now need to save it to mem.
+
+ // Find the largest store unit
+ MVT StoreType = MVT::i8;
+ for (unsigned tp = MVT::FIRST_INTEGER_VALUETYPE;
+ tp < MVT::LAST_INTEGER_VALUETYPE; ++tp) {
+ MVT Tp = (MVT::SimpleValueType)tp;
+ if (TLI.isTypeLegal(Tp) && Tp.getSizeInBits() <= NumElems * ToEltSz)
+ StoreType = Tp;
+ }
+ // Didn't find a legal store type.
+ if (!TLI.isTypeLegal(StoreType))
+ return SDValue();
+
+ // Bitcast the original vector into a vector of store-size units
+ EVT StoreVecVT = EVT::getVectorVT(*DAG.getContext(),
+ StoreType, VT.getSizeInBits()/EVT(StoreType).getSizeInBits());
+ assert(StoreVecVT.getSizeInBits() == VT.getSizeInBits());
+ SDValue ShuffWide = DAG.getNode(ISD::BITCAST, DL, StoreVecVT, Shuff);
+ SmallVector<SDValue, 8> Chains;
+ SDValue Increment = DAG.getConstant(StoreType.getSizeInBits()/8,
+ TLI.getPointerTy());
+ SDValue BasePtr = St->getBasePtr();
+
+ // Perform one or more big stores into memory.
+ unsigned E = (ToEltSz*NumElems)/StoreType.getSizeInBits();
+ for (unsigned I = 0; I < E; I++) {
+ SDValue SubVec = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL,
+ StoreType, ShuffWide,
+ DAG.getIntPtrConstant(I));
+ SDValue Ch = DAG.getStore(St->getChain(), DL, SubVec, BasePtr,
+ St->getPointerInfo(), St->isVolatile(),
+ St->isNonTemporal(), St->getAlignment());
+ BasePtr = DAG.getNode(ISD::ADD, DL, BasePtr.getValueType(), BasePtr,
+ Increment);
+ Chains.push_back(Ch);
+ }
+ return DAG.getNode(ISD::TokenFactor, DL, MVT::Other, &Chains[0],
+ Chains.size());
+ }
+
+ if (!ISD::isNormalStore(St))
return SDValue();
// Split a store of a VMOVDRR into two integer stores to avoid mixing NEON and