[SelectionDAG] Refactor lowering of atomic memory intrinsics.

Summary:
This just refactors the lowering of the atomic memory intrinsics to more
closely match the code patterns used in the lowering of the non-atomic
memory intrinsics. Specifically, we encapsulate the lowering in
SelectionDAG::getAtomicMem*() functions rather than embedding
the code directly in the SelectionDAGBuilder code.

llvm-svn: 330603

3 files changed, 167 insertions, 91 deletions

diff --git a/llvm/include/llvm/CodeGen/SelectionDAG.h b/llvm/include/llvm/CodeGen/SelectionDAG.h
index af43c9b0834..fd64b91b1af 100644
--- a/llvm/include/llvm/CodeGen/SelectionDAG.h
+++ b/llvm/include/llvm/CodeGen/SelectionDAG.h
@@ -917,6 +917,23 @@ public:
                     SDValue Size, unsigned Align, bool isVol, bool isTailCall,
                     MachinePointerInfo DstPtrInfo);
 
+  SDValue getAtomicMemcpy(SDValue Chain, const SDLoc &dl, SDValue Dst,
+                          unsigned DstAlign, SDValue Src, unsigned SrcAlign,
+                          SDValue Size, Type *SizeTy, unsigned ElemSz,
+                          bool isTailCall, MachinePointerInfo DstPtrInfo,
+                          MachinePointerInfo SrcPtrInfo);
+
+  SDValue getAtomicMemmove(SDValue Chain, const SDLoc &dl, SDValue Dst,
+                           unsigned DstAlign, SDValue Src, unsigned SrcAlign,
+                           SDValue Size, Type *SizeTy, unsigned ElemSz,
+                           bool isTailCall, MachinePointerInfo DstPtrInfo,
+                           MachinePointerInfo SrcPtrInfo);
+
+  SDValue getAtomicMemset(SDValue Chain, const SDLoc &dl, SDValue Dst,
+                          unsigned DstAlign, SDValue Value, SDValue Size,
+                          Type *SizeTy, unsigned ElemSz, bool isTailCall,
+                          MachinePointerInfo DstPtrInfo);
+
   /// Helper function to make it easier to build SetCC's if you just
   /// have an ISD::CondCode instead of an SDValue.
   ///
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index d57f0bf92a3..bf48ae28f8a 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -5630,6 +5630,47 @@ SDValue SelectionDAG::getMemcpy(SDValue Chain, const SDLoc &dl, SDValue Dst,
   return CallResult.second;
 }
 
+SDValue SelectionDAG::getAtomicMemcpy(SDValue Chain, const SDLoc &dl,
+                                      SDValue Dst, unsigned DstAlign,
+                                      SDValue Src, unsigned SrcAlign,
+                                      SDValue Size, Type *SizeTy,
+                                      unsigned ElemSz, bool isTailCall,
+                                      MachinePointerInfo DstPtrInfo,
+                                      MachinePointerInfo SrcPtrInfo) {
+  // Emit a library call.
+  TargetLowering::ArgListTy Args;
+  TargetLowering::ArgListEntry Entry;
+  Entry.Ty = getDataLayout().getIntPtrType(*getContext());
+  Entry.Node = Dst;
+  Args.push_back(Entry);
+
+  Entry.Node = Src;
+  Args.push_back(Entry);
+
+  Entry.Ty = SizeTy;
+  Entry.Node = Size;
+  Args.push_back(Entry);
+
+  RTLIB::Libcall LibraryCall =
+      RTLIB::getMEMCPY_ELEMENT_UNORDERED_ATOMIC(ElemSz);
+  if (LibraryCall == RTLIB::UNKNOWN_LIBCALL)
+    report_fatal_error("Unsupported element size");
+
+  TargetLowering::CallLoweringInfo CLI(*this);
+  CLI.setDebugLoc(dl)
+      .setChain(Chain)
+      .setLibCallee(TLI->getLibcallCallingConv(LibraryCall),
+                    Type::getVoidTy(*getContext()),
+                    getExternalSymbol(TLI->getLibcallName(LibraryCall),
+                                      TLI->getPointerTy(getDataLayout())),
+                    std::move(Args))
+      .setDiscardResult()
+      .setTailCall(isTailCall);
+
+  std::pair<SDValue, SDValue> CallResult = TLI->LowerCallTo(CLI);
+  return CallResult.second;
+}
+
 SDValue SelectionDAG::getMemmove(SDValue Chain, const SDLoc &dl, SDValue Dst,
                                  SDValue Src, SDValue Size, unsigned Align,
                                  bool isVol, bool isTailCall,
@@ -5691,6 +5732,47 @@ SDValue SelectionDAG::getMemmove(SDValue Chain, const SDLoc &dl, SDValue Dst,
   return CallResult.second;
 }
 
+SDValue SelectionDAG::getAtomicMemmove(SDValue Chain, const SDLoc &dl,
+                                       SDValue Dst, unsigned DstAlign,
+                                       SDValue Src, unsigned SrcAlign,
+                                       SDValue Size, Type *SizeTy,
+                                       unsigned ElemSz, bool isTailCall,
+                                       MachinePointerInfo DstPtrInfo,
+                                       MachinePointerInfo SrcPtrInfo) {
+  // Emit a library call.
+  TargetLowering::ArgListTy Args;
+  TargetLowering::ArgListEntry Entry;
+  Entry.Ty = getDataLayout().getIntPtrType(*getContext());
+  Entry.Node = Dst;
+  Args.push_back(Entry);
+
+  Entry.Node = Src;
+  Args.push_back(Entry);
+
+  Entry.Ty = SizeTy;
+  Entry.Node = Size;
+  Args.push_back(Entry);
+
+  RTLIB::Libcall LibraryCall =
+      RTLIB::getMEMMOVE_ELEMENT_UNORDERED_ATOMIC(ElemSz);
+  if (LibraryCall == RTLIB::UNKNOWN_LIBCALL)
+    report_fatal_error("Unsupported element size");
+
+  TargetLowering::CallLoweringInfo CLI(*this);
+  CLI.setDebugLoc(dl)
+      .setChain(Chain)
+      .setLibCallee(TLI->getLibcallCallingConv(LibraryCall),
+                    Type::getVoidTy(*getContext()),
+                    getExternalSymbol(TLI->getLibcallName(LibraryCall),
+                                      TLI->getPointerTy(getDataLayout())),
+                    std::move(Args))
+      .setDiscardResult()
+      .setTailCall(isTailCall);
+
+  std::pair<SDValue, SDValue> CallResult = TLI->LowerCallTo(CLI);
+  return CallResult.second;
+}
+
 SDValue SelectionDAG::getMemset(SDValue Chain, const SDLoc &dl, SDValue Dst,
                                 SDValue Src, SDValue Size, unsigned Align,
                                 bool isVol, bool isTailCall,
@@ -5753,6 +5835,46 @@ SDValue SelectionDAG::getMemset(SDValue Chain, const SDLoc &dl, SDValue Dst,
   return CallResult.second;
 }
 
+SDValue SelectionDAG::getAtomicMemset(SDValue Chain, const SDLoc &dl,
+                                      SDValue Dst, unsigned DstAlign,
+                                      SDValue Value, SDValue Size, Type *SizeTy,
+                                      unsigned ElemSz, bool isTailCall,
+                                      MachinePointerInfo DstPtrInfo) {
+  // Emit a library call.
+  TargetLowering::ArgListTy Args;
+  TargetLowering::ArgListEntry Entry;
+  Entry.Ty = getDataLayout().getIntPtrType(*getContext());
+  Entry.Node = Dst;
+  Args.push_back(Entry);
+
+  Entry.Ty = Type::getInt8Ty(*getContext());
+  Entry.Node = Value;
+  Args.push_back(Entry);
+
+  Entry.Ty = SizeTy;
+  Entry.Node = Size;
+  Args.push_back(Entry);
+
+  RTLIB::Libcall LibraryCall =
+      RTLIB::getMEMSET_ELEMENT_UNORDERED_ATOMIC(ElemSz);
+  if (LibraryCall == RTLIB::UNKNOWN_LIBCALL)
+    report_fatal_error("Unsupported element size");
+
+  TargetLowering::CallLoweringInfo CLI(*this);
+  CLI.setDebugLoc(dl)
+      .setChain(Chain)
+      .setLibCallee(TLI->getLibcallCallingConv(LibraryCall),
+                    Type::getVoidTy(*getContext()),
+                    getExternalSymbol(TLI->getLibcallName(LibraryCall),
+                                      TLI->getPointerTy(getDataLayout())),
+                    std::move(Args))
+      .setDiscardResult()
+      .setTailCall(isTailCall);
+
+  std::pair<SDValue, SDValue> CallResult = TLI->LowerCallTo(CLI);
+  return CallResult.second;
+}
+
 SDValue SelectionDAG::getAtomic(unsigned Opcode, const SDLoc &dl, EVT MemVT,
                                 SDVTList VTList, ArrayRef<SDValue> Ops,
                                 MachineMemOperand *MMO) {
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 0b2fd9b8225..5e6edd0ca63 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -5098,36 +5098,16 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
     SDValue Src = getValue(MI.getRawSource());
     SDValue Length = getValue(MI.getLength());
 
-    // Emit a library call.
-    TargetLowering::ArgListTy Args;
-    TargetLowering::ArgListEntry Entry;
-    Entry.Ty = DAG.getDataLayout().getIntPtrType(*DAG.getContext());
-    Entry.Node = Dst;
-    Args.push_back(Entry);
-
-    Entry.Node = Src;
-    Args.push_back(Entry);
-
-    Entry.Ty = MI.getLength()->getType();
-    Entry.Node = Length;
-    Args.push_back(Entry);
-
-    uint64_t ElementSizeConstant = MI.getElementSizeInBytes();
-    RTLIB::Libcall LibraryCall =
-        RTLIB::getMEMCPY_ELEMENT_UNORDERED_ATOMIC(ElementSizeConstant);
-    if (LibraryCall == RTLIB::UNKNOWN_LIBCALL)
-      report_fatal_error("Unsupported element size");
-
-    TargetLowering::CallLoweringInfo CLI(DAG);
-    CLI.setDebugLoc(sdl).setChain(getRoot()).setLibCallee(
-        TLI.getLibcallCallingConv(LibraryCall),
-        Type::getVoidTy(*DAG.getContext()),
-        DAG.getExternalSymbol(TLI.getLibcallName(LibraryCall),
-                              TLI.getPointerTy(DAG.getDataLayout())),
-        std::move(Args));
-
-    std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
-    DAG.setRoot(CallResult.second);
+    unsigned DstAlign = MI.getDestAlignment();
+    unsigned SrcAlign = MI.getSourceAlignment();
+    Type *LengthTy = MI.getLength()->getType();
+    unsigned ElemSz = MI.getElementSizeInBytes();
+    bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget());
+    SDValue MC = DAG.getAtomicMemcpy(getRoot(), sdl, Dst, DstAlign, Src,
+                                     SrcAlign, Length, LengthTy, ElemSz, isTC,
+                                     MachinePointerInfo(MI.getRawDest()),
+                                     MachinePointerInfo(MI.getRawSource()));
+    updateDAGForMaybeTailCall(MC);
     return nullptr;
   }
   case Intrinsic::memmove_element_unordered_atomic: {
@@ -5136,36 +5116,16 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
     SDValue Src = getValue(MI.getRawSource());
     SDValue Length = getValue(MI.getLength());
 
-    // Emit a library call.
-    TargetLowering::ArgListTy Args;
-    TargetLowering::ArgListEntry Entry;
-    Entry.Ty = DAG.getDataLayout().getIntPtrType(*DAG.getContext());
-    Entry.Node = Dst;
-    Args.push_back(Entry);
-
-    Entry.Node = Src;
-    Args.push_back(Entry);
-
-    Entry.Ty = MI.getLength()->getType();
-    Entry.Node = Length;
-    Args.push_back(Entry);
-
-    uint64_t ElementSizeConstant = MI.getElementSizeInBytes();
-    RTLIB::Libcall LibraryCall =
-        RTLIB::getMEMMOVE_ELEMENT_UNORDERED_ATOMIC(ElementSizeConstant);
-    if (LibraryCall == RTLIB::UNKNOWN_LIBCALL)
-      report_fatal_error("Unsupported element size");
-
-    TargetLowering::CallLoweringInfo CLI(DAG);
-    CLI.setDebugLoc(sdl).setChain(getRoot()).setLibCallee(
-        TLI.getLibcallCallingConv(LibraryCall),
-        Type::getVoidTy(*DAG.getContext()),
-        DAG.getExternalSymbol(TLI.getLibcallName(LibraryCall),
-                              TLI.getPointerTy(DAG.getDataLayout())),
-        std::move(Args));
-
-    std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
-    DAG.setRoot(CallResult.second);
+    unsigned DstAlign = MI.getDestAlignment();
+    unsigned SrcAlign = MI.getSourceAlignment();
+    Type *LengthTy = MI.getLength()->getType();
+    unsigned ElemSz = MI.getElementSizeInBytes();
+    bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget());
+    SDValue MC = DAG.getAtomicMemmove(getRoot(), sdl, Dst, DstAlign, Src,
+                                      SrcAlign, Length, LengthTy, ElemSz, isTC,
+                                      MachinePointerInfo(MI.getRawDest()),
+                                      MachinePointerInfo(MI.getRawSource()));
+    updateDAGForMaybeTailCall(MC);
     return nullptr;
   }
   case Intrinsic::memset_element_unordered_atomic: {
@@ -5174,37 +5134,14 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
     SDValue Val = getValue(MI.getValue());
     SDValue Length = getValue(MI.getLength());
 
-    // Emit a library call.
-    TargetLowering::ArgListTy Args;
-    TargetLowering::ArgListEntry Entry;
-    Entry.Ty = DAG.getDataLayout().getIntPtrType(*DAG.getContext());
-    Entry.Node = Dst;
-    Args.push_back(Entry);
-
-    Entry.Ty = Type::getInt8Ty(*DAG.getContext());
-    Entry.Node = Val;
-    Args.push_back(Entry);
-
-    Entry.Ty = MI.getLength()->getType();
-    Entry.Node = Length;
-    Args.push_back(Entry);
-
-    uint64_t ElementSizeConstant = MI.getElementSizeInBytes();
-    RTLIB::Libcall LibraryCall =
-        RTLIB::getMEMSET_ELEMENT_UNORDERED_ATOMIC(ElementSizeConstant);
-    if (LibraryCall == RTLIB::UNKNOWN_LIBCALL)
-      report_fatal_error("Unsupported element size");
-
-    TargetLowering::CallLoweringInfo CLI(DAG);
-    CLI.setDebugLoc(sdl).setChain(getRoot()).setLibCallee(
-        TLI.getLibcallCallingConv(LibraryCall),
-        Type::getVoidTy(*DAG.getContext()),
-        DAG.getExternalSymbol(TLI.getLibcallName(LibraryCall),
-                              TLI.getPointerTy(DAG.getDataLayout())),
-        std::move(Args));
-
-    std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
-    DAG.setRoot(CallResult.second);
+    unsigned DstAlign = MI.getDestAlignment();
+    Type *LengthTy = MI.getLength()->getType();
+    unsigned ElemSz = MI.getElementSizeInBytes();
+    bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget());
+    SDValue MC = DAG.getAtomicMemset(getRoot(), sdl, Dst, DstAlign, Val, Length,
+                                     LengthTy, ElemSz, isTC,
+                                     MachinePointerInfo(MI.getRawDest()));
+    updateDAGForMaybeTailCall(MC);
     return nullptr;
   }
   case Intrinsic::dbg_addr: