2 files changed, 35 insertions, 6 deletions

diff --git a/llvm/lib/Target/ARM/ARMCallLowering.cpp b/llvm/lib/Target/ARM/ARMCallLowering.cpp
index c5b49ef70fd..f37d6d7b1d0 100644
--- a/llvm/lib/Target/ARM/ARMCallLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMCallLowering.cpp
@@ -19,6 +19,7 @@
 #include "ARMISelLowering.h"
 #include "ARMSubtarget.h"
 
+#include "llvm/CodeGen/Analysis.h"
 #include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 
@@ -74,6 +75,25 @@ struct FuncReturnHandler : public CallLowering::ValueHandler {
 };
 } // End anonymous namespace.
 
+void ARMCallLowering::splitToValueTypes(const ArgInfo &OrigArg,
+                                        SmallVectorImpl<ArgInfo> &SplitArgs,
+                                        const DataLayout &DL,
+                                        MachineRegisterInfo &MRI) const {
+  const ARMTargetLowering &TLI = *getTLI<ARMTargetLowering>();
+  LLVMContext &Ctx = OrigArg.Ty->getContext();
+
+  SmallVector<EVT, 4> SplitVTs;
+  SmallVector<uint64_t, 4> Offsets;
+  ComputeValueVTs(TLI, DL, OrigArg.Ty, SplitVTs, &Offsets, 0);
+
+  assert(SplitVTs.size() == 1 && "Unsupported type");
+
+  // Even if there is no splitting to do, we still want to replace the original
+  // type (e.g. pointer type -> integer).
+  SplitArgs.emplace_back(OrigArg.Reg, SplitVTs[0].getTypeForEVT(Ctx),
+                         OrigArg.Flags, OrigArg.IsFixed);
+}
+
 /// Lower the return value for the already existing \p Ret. This assumes that
 /// \p MIRBuilder's insertion point is correct.
 bool ARMCallLowering::lowerReturnVal(MachineIRBuilder &MIRBuilder,
@@ -91,14 +111,16 @@ bool ARMCallLowering::lowerReturnVal(MachineIRBuilder &MIRBuilder,
   if (!isSupportedType(DL, TLI, Val->getType()))
     return false;
 
-  CCAssignFn *AssignFn =
-      TLI.CCAssignFnForReturn(F.getCallingConv(), F.isVarArg());
-
+  SmallVector<ArgInfo, 4> SplitVTs;
   ArgInfo RetInfo(VReg, Val->getType());
   setArgFlags(RetInfo, AttributeSet::ReturnIndex, DL, F);
+  splitToValueTypes(RetInfo, SplitVTs, DL, MF.getRegInfo());
+
+  CCAssignFn *AssignFn =
+      TLI.CCAssignFnForReturn(F.getCallingConv(), F.isVarArg());
 
   FuncReturnHandler RetHandler(MIRBuilder, MF.getRegInfo(), Ret, AssignFn);
-  return handleAssignments(MIRBuilder, RetInfo, RetHandler);
+  return handleAssignments(MIRBuilder, SplitVTs, RetHandler);
 }
 
 bool ARMCallLowering::lowerReturn(MachineIRBuilder &MIRBuilder,
@@ -179,7 +201,8 @@ bool ARMCallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder,
   if (F.isVarArg())
     return false;
 
-  auto DL = MIRBuilder.getMF().getDataLayout();
+  auto &MF = MIRBuilder.getMF();
+  auto DL = MF.getDataLayout();
   auto &TLI = *getTLI<ARMTargetLowering>();
 
   if (TLI.getSubtarget()->isThumb())
@@ -198,7 +221,7 @@ bool ARMCallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder,
   for (auto &Arg : Args) {
     ArgInfo AInfo(VRegs[Idx], Arg.getType());
     setArgFlags(AInfo, Idx + 1, DL, F);
-    ArgInfos.push_back(AInfo);
+    splitToValueTypes(AInfo, ArgInfos, DL, MF.getRegInfo());
     Idx++;
   }
 
diff --git a/llvm/lib/Target/ARM/ARMCallLowering.h b/llvm/lib/Target/ARM/ARMCallLowering.h
index 6a1b886b501..7c3b3ddec74 100644
--- a/llvm/lib/Target/ARM/ARMCallLowering.h
+++ b/llvm/lib/Target/ARM/ARMCallLowering.h
@@ -37,6 +37,12 @@ public:
 private:
   bool lowerReturnVal(MachineIRBuilder &MIRBuilder, const Value *Val,
                       unsigned VReg, MachineInstrBuilder &Ret) const;
+
+  /// Split an argument into one or more arguments that the CC lowering can cope
+  /// with (e.g. replace pointers with integers).
+  void splitToValueTypes(const ArgInfo &OrigArg,
+                         SmallVectorImpl<ArgInfo> &SplitArgs,
+                         const DataLayout &DL, MachineRegisterInfo &MRI) const;
 };
 } // End of namespace llvm
 #endif