diff --git a/llvm/include/llvm/CodeGen/TargetLowering.h b/llvm/include/llvm/CodeGen/TargetLowering.h
--- a/llvm/include/llvm/CodeGen/TargetLowering.h
+++ b/llvm/include/llvm/CodeGen/TargetLowering.h
@@ -288,6 +288,7 @@
     bool IsCFGuardTarget : 1;
     MaybeAlign Alignment = None;
     Type *ByValType = nullptr;
+    Type *InAllocaType = nullptr;
     Type *PreallocatedType = nullptr;
 
     ArgListEntry()
diff --git a/llvm/include/llvm/IR/InstrTypes.h b/llvm/include/llvm/IR/InstrTypes.h
--- a/llvm/include/llvm/IR/InstrTypes.h
+++ b/llvm/include/llvm/IR/InstrTypes.h
@@ -1741,6 +1741,12 @@
     return Ty ? Ty : getArgOperand(ArgNo)->getType()->getPointerElementType();
   }
 
+  /// Extract the inalloca type for a call or parameter.
+  Type *getParamInAllocaType(unsigned ArgNo) const {
+    Type *Ty = Attrs.getParamInAllocaType(ArgNo);
+    return Ty ? Ty : getArgOperand(ArgNo)->getType()->getPointerElementType();
+  }
+
   /// Extract the preallocated type for a call or parameter.
   Type *getParamPreallocatedType(unsigned ArgNo) const {
     Type *Ty = Attrs.getParamPreallocatedType(ArgNo);
diff --git a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
--- a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -1033,7 +1033,7 @@
   for (auto &Arg : CLI.getArgs()) {
     Type *FinalType = Arg.Ty;
     if (Arg.IsByVal)
-      FinalType = cast<PointerType>(Arg.Ty)->getElementType();
+      FinalType = Arg.ByValType;
     bool NeedsRegBlock = TLI.functionArgumentNeedsConsecutiveRegisters(
         FinalType, CLI.CallConv, CLI.IsVarArg);
 
@@ -1074,8 +1074,15 @@
     }
     MaybeAlign MemAlign = Arg.Alignment;
     if (Arg.IsByVal || Arg.IsInAlloca || Arg.IsPreallocated) {
-      PointerType *Ty = cast<PointerType>(Arg.Ty);
-      Type *ElementTy = Ty->getElementType();
+      Type *ElementTy;
+      if (Arg.IsByVal)
+        ElementTy = Arg.ByValType;
+      else if (Arg.IsInAlloca)
+        ElementTy = Arg.InAllocaType;
+      else
+        ElementTy = Arg.PreallocatedType;
+      assert(ElementTy && "Indirect type not set in ArgListEntry");
+
       unsigned FrameSize =
           DL.getTypeAllocSize(Arg.ByValType ? Arg.ByValType : ElementTy);
 
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -9409,8 +9409,8 @@
     ComputeValueVTs(*this, DL, Args[i].Ty, ValueVTs);
     // FIXME: Split arguments if CLI.IsPostTypeLegalization
     Type *FinalType = Args[i].Ty;
-    if (Args[i].IsByVal)
-      FinalType = cast<PointerType>(Args[i].Ty)->getElementType();
+    if (Args[i].ByValType)
+      FinalType = Args[i].ByValType;
     bool NeedsRegBlock = functionArgumentNeedsConsecutiveRegisters(
         FinalType, CLI.CallConv, CLI.IsVarArg);
     for (unsigned Value = 0, NumValues = ValueVTs.size(); Value != NumValues;
@@ -9481,8 +9481,14 @@
       }
       Align MemAlign;
       if (Args[i].IsByVal || Args[i].IsInAlloca || Args[i].IsPreallocated) {
-        PointerType *Ty = cast<PointerType>(Args[i].Ty);
-        Type *ElementTy = Ty->getElementType();
+        Type *ElementTy;
+        if (Args[i].IsByVal)
+          ElementTy = Args[i].ByValType;
+        else if (Args[i].IsInAlloca)
+          ElementTy = Args[i].InAllocaType;
+        else
+          ElementTy = Args[i].PreallocatedType;
+        assert(ElementTy && "Indirect type not set in ArgListEntry");
 
         unsigned FrameSize = DL.getTypeAllocSize(
             Args[i].ByValType ? Args[i].ByValType : ElementTy);
diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -124,6 +124,9 @@
     if (!Alignment)
       Alignment = Call->getParamAlign(ArgIdx);
   }
+  InAllocaType = nullptr;
+  if (IsInAlloca)
+    InAllocaType = Call->getParamInAllocaType(ArgIdx);
   PreallocatedType = nullptr;
   if (IsPreallocated)
     PreallocatedType = Call->getParamPreallocatedType(ArgIdx);