[SOL] Set max stores per mem func depending on the target features (#14)

Author: dmakarov

llvm/lib/Target/BPF/BPFISelLowering.cpp

@@ -162,9 +162,11 @@ BPFTargetLowering::BPFTargetLowering(const TargetMachine &TM,
     MaxStoresPerMemcpy = MaxStoresPerMemcpyOptSize = 0;
     MaxStoresPerMemmove = MaxStoresPerMemmoveOptSize = 0;
   } else {
+    auto SelectionDAGInfo = STI.getSelectionDAGInfo();
+    SelectionDAGInfo->setSolanaFlag(STI.isSolana());
     // inline memcpy() for kernel to see explicit copy
     unsigned CommonMaxStores =
-      STI.getSelectionDAGInfo()->getCommonMaxStoresPerMemFunc();
+      SelectionDAGInfo->getCommonMaxStoresPerMemFunc();
 
     MaxStoresPerMemset = MaxStoresPerMemsetOptSize = CommonMaxStores;
     MaxStoresPerMemcpy = MaxStoresPerMemcpyOptSize = CommonMaxStores;

llvm/lib/Target/BPF/BPFSelectionDAGInfo.h

@@ -19,14 +19,23 @@ namespace llvm {
 
 class BPFSelectionDAGInfo : public SelectionDAGTargetInfo {
 public:
+  BPFSelectionDAGInfo() : isSolana(false) {}
   SDValue EmitTargetCodeForMemcpy(SelectionDAG &DAG, const SDLoc &dl,
                                   SDValue Chain, SDValue Dst, SDValue Src,
                                   SDValue Size, Align Alignment,
                                   bool isVolatile, bool AlwaysInline,
                                   MachinePointerInfo DstPtrInfo,
                                   MachinePointerInfo SrcPtrInfo) const override;
 
-  unsigned getCommonMaxStoresPerMemFunc() const { return 128; }
+  unsigned getCommonMaxStoresPerMemFunc() const {
+    return isSolana ? 4 : 128;
+  }
+  void setSolanaFlag(bool value) const {
+    isSolana = value;
+  }
+
+private:
+  mutable bool isSolana;
 
 };
 

llvm/lib/Target/BPF/BPFSubtarget.cpp

@@ -62,4 +62,6 @@ BPFSubtarget::BPFSubtarget(const Triple &TT, const std::string &CPU,
                            const std::string &FS, const TargetMachine &TM)
     : BPFGenSubtargetInfo(TT, CPU, /*TuneCPU*/ CPU, FS), InstrInfo(),
       FrameLowering(initializeSubtargetDependencies(CPU, FS)),
-      TLInfo(TM, *this) {}
+      TLInfo(TM, *this) {
+  TSInfo.setSolanaFlag(IsSolana);
+}