[llvm] 17bd86b - [LegalizeVectorTypes] Create correct memoperands in SplitVecRes_INSERT_SUBVECTOR.

[Craig Topper via llvm-commits]

Author: Craig Topper
Date: 2020-05-20T15:06:36-07:00
New Revision: 17bd86bc9bf0e696fb914ae5befb68ea9a847c82

URL: https://github.com/llvm/llvm-project/commit/17bd86bc9bf0e696fb914ae5befb68ea9a847c82
DIFF: https://github.com/llvm/llvm-project/commit/17bd86bc9bf0e696fb914ae5befb68ea9a847c82.diff

LOG: [LegalizeVectorTypes] Create correct memoperands in SplitVecRes_INSERT_SUBVECTOR.

Previously this code just used a default constructed
MachinePointerInfo. But we know the accesses are to a fixed stack
object or at least somewhere on the stack.

While there fix the alignment passed to the full vector load/stores.

I don't think this function is currently exercised in tree so I
don't know how to test it. I just noticed it when I removed
non-constant index support in this function.

Differential Revision: https://reviews.llvm.org/D80058

Added: 
    

Modified: 
    llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp

Removed: 
    


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diff  --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
index 00601bcba452..6601dc68223e 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
@@ -1155,27 +1155,30 @@ void DAGTypeLegalizer::SplitVecRes_INSERT_SUBVECTOR(SDNode *N, SDValue &Lo,
 
   // Spill the vector to the stack.
   SDValue StackPtr = DAG.CreateStackTemporary(VecVT);
+  auto &MF = DAG.getMachineFunction();
+  auto FrameIndex = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
+  auto PtrInfo = MachinePointerInfo::getFixedStack(MF, FrameIndex);
+  Type *VecType = VecVT.getTypeForEVT(*DAG.getContext());
+  Align Alignment = DAG.getDataLayout().getPrefTypeAlign(VecType);
+
   SDValue Store =
-      DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr, MachinePointerInfo());
+      DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr, PtrInfo, Alignment);
 
   // Store the new subvector into the specified index.
   SDValue SubVecPtr = TLI.getVectorElementPointer(DAG, StackPtr, VecVT, Idx);
-  Type *VecType = VecVT.getTypeForEVT(*DAG.getContext());
-  Align Alignment = DAG.getDataLayout().getPrefTypeAlign(VecType);
-  Store = DAG.getStore(Store, dl, SubVec, SubVecPtr, MachinePointerInfo());
+  Store = DAG.getStore(Store, dl, SubVec, SubVecPtr,
+                       MachinePointerInfo::getUnknownStack(MF));
 
   // Load the Lo part from the stack slot.
-  Lo =
-      DAG.getLoad(Lo.getValueType(), dl, Store, StackPtr, MachinePointerInfo());
+  Lo = DAG.getLoad(Lo.getValueType(), dl, Store, StackPtr, PtrInfo, Alignment);
 
   // Increment the pointer to the other part.
   unsigned IncrementSize = Lo.getValueSizeInBits() / 8;
   StackPtr = DAG.getMemBasePlusOffset(StackPtr, IncrementSize, dl);
 
   // Load the Hi part from the stack slot.
-  Hi =
-      DAG.getLoad(Hi.getValueType(), dl, Store, StackPtr,
-                  MachinePointerInfo().getWithOffset(IncrementSize), Alignment);
+  Hi = DAG.getLoad(Hi.getValueType(), dl, Store, StackPtr,
+                   PtrInfo.getWithOffset(IncrementSize), Alignment);
 }
 
 void DAGTypeLegalizer::SplitVecRes_FPOWI(SDNode *N, SDValue &Lo,
@@ -1451,13 +1454,15 @@ void DAGTypeLegalizer::SplitVecRes_INSERT_VECTOR_ELT(SDNode *N, SDValue &Lo,
   auto &MF = DAG.getMachineFunction();
   auto FrameIndex = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
   auto PtrInfo = MachinePointerInfo::getFixedStack(MF, FrameIndex);
-  SDValue Store = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr, PtrInfo);
+  Type *VecType = VecVT.getTypeForEVT(*DAG.getContext());
+  Align Alignment = DAG.getDataLayout().getPrefTypeAlign(VecType);
+
+  SDValue Store =
+      DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr, PtrInfo, Alignment);
 
   // Store the new element.  This may be larger than the vector element type,
   // so use a truncating store.
   SDValue EltPtr = TLI.getVectorElementPointer(DAG, StackPtr, VecVT, Idx);
-  Type *VecType = VecVT.getTypeForEVT(*DAG.getContext());
-  Align Alignment = DAG.getDataLayout().getPrefTypeAlign(VecType);
   Store = DAG.getTruncStore(Store, dl, Elt, EltPtr,
                             MachinePointerInfo::getUnknownStack(MF), EltVT);
 
@@ -1465,13 +1470,11 @@ void DAGTypeLegalizer::SplitVecRes_INSERT_VECTOR_ELT(SDNode *N, SDValue &Lo,
   std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(VecVT);
 
   // Load the Lo part from the stack slot.
-  Lo = DAG.getLoad(LoVT, dl, Store, StackPtr, PtrInfo);
+  Lo = DAG.getLoad(LoVT, dl, Store, StackPtr, PtrInfo, Alignment);
 
   // Increment the pointer to the other part.
   unsigned IncrementSize = LoVT.getSizeInBits() / 8;
-  StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
-                         DAG.getConstant(IncrementSize, dl,
-                                         StackPtr.getValueType()));
+  StackPtr = DAG.getMemBasePlusOffset(StackPtr, IncrementSize, dl);
 
   // Load the Hi part from the stack slot.
   Hi = DAG.getLoad(HiVT, dl, Store, StackPtr,