diff --git a/llvm/include/llvm/IR/DerivedTypes.h b/llvm/include/llvm/IR/DerivedTypes.h
--- a/llvm/include/llvm/IR/DerivedTypes.h
+++ b/llvm/include/llvm/IR/DerivedTypes.h
@@ -696,6 +696,14 @@
     return isOpaque() || PointeeTy == Ty;
   }
 
+  /// Return true if both pointer types have the same element type. Two opaque
+  /// pointers are considered to have the same element type, while an opaque
+  /// and a non-opaque pointer have different element types.
+  /// TODO: Remove after opaque pointer transition is complete.
+  bool hasSameElementTypeAs(PointerType *Other) {
+    return PointeeTy == Other->PointeeTy;
+  }
+
   /// Implement support type inquiry through isa, cast, and dyn_cast.
   static bool classof(const Type *T) {
     return T->getTypeID() == PointerTyID;
diff --git a/llvm/lib/IR/Instructions.cpp b/llvm/lib/IR/Instructions.cpp
--- a/llvm/lib/IR/Instructions.cpp
+++ b/llvm/lib/IR/Instructions.cpp
@@ -2891,13 +2891,15 @@
         "Illegal addrspacecast, bitcast sequence!");
       // Allowed, use first cast's opcode
       return firstOp;
-    case 14:
+    case 14: {
       // bitcast, addrspacecast -> addrspacecast if the element type of
       // bitcast's source is the same as that of addrspacecast's destination.
-      if (SrcTy->getScalarType()->getPointerElementType() ==
-          DstTy->getScalarType()->getPointerElementType())
+      PointerType *SrcPtrTy = cast<PointerType>(SrcTy->getScalarType());
+      PointerType *DstPtrTy = cast<PointerType>(DstTy->getScalarType());
+      if (SrcPtrTy->hasSameElementTypeAs(DstPtrTy))
         return Instruction::AddrSpaceCast;
       return 0;
+    }
     case 15:
       // FIXME: this state can be merged with (1), but the following assert
       // is useful to check the correcteness of the sequence due to semantic
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
--- a/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCasts.cpp
@@ -2798,9 +2798,9 @@
   PointerType *SrcTy = cast<PointerType>(Src->getType()->getScalarType());
   PointerType *DestTy = cast<PointerType>(CI.getType()->getScalarType());
 
-  Type *DestElemTy = DestTy->getElementType();
-  if (SrcTy->getElementType() != DestElemTy) {
-    Type *MidTy = PointerType::get(DestElemTy, SrcTy->getAddressSpace());
+  if (!SrcTy->hasSameElementTypeAs(DestTy)) {
+    Type *MidTy =
+        PointerType::getWithSamePointeeType(DestTy, SrcTy->getAddressSpace());
     // Handle vectors of pointers.
     if (VectorType *VT = dyn_cast<VectorType>(CI.getType()))
       MidTy = VectorType::get(MidTy, VT->getElementCount());
diff --git a/llvm/test/Transforms/InstCombine/opaque-ptr.ll b/llvm/test/Transforms/InstCombine/opaque-ptr.ll
--- a/llvm/test/Transforms/InstCombine/opaque-ptr.ll
+++ b/llvm/test/Transforms/InstCombine/opaque-ptr.ll
@@ -35,20 +35,44 @@
   ret ptr bitcast (i8* @g to ptr)
 }
 
-;define ptr @addrspacecast_opaque_to_opaque(ptr addrspace(1) %a) {
-;  %b = addrspacecast ptr addrspace(1) %a to ptr
-;  ret ptr %b
-;}
+define ptr @addrspacecast_opaque_to_opaque(ptr addrspace(1) %a) {
+; CHECK-LABEL: @addrspacecast_opaque_to_opaque(
+; CHECK-NEXT:    [[B:%.*]] = addrspacecast ptr addrspace(1) [[A:%.*]] to ptr
+; CHECK-NEXT:    ret ptr [[B]]
+;
+  %b = addrspacecast ptr addrspace(1) %a to ptr
+  ret ptr %b
+}
+
+define ptr @addrspacecast_typed_to_opaque(i8 addrspace(1)* %a) {
+; CHECK-LABEL: @addrspacecast_typed_to_opaque(
+; CHECK-NEXT:    [[TMP1:%.*]] = bitcast i8 addrspace(1)* [[A:%.*]] to ptr addrspace(1)
+; CHECK-NEXT:    [[B:%.*]] = addrspacecast ptr addrspace(1) [[TMP1]] to ptr
+; CHECK-NEXT:    ret ptr [[B]]
+;
+  %b = addrspacecast i8 addrspace(1)* %a to ptr
+  ret ptr %b
+}
 
-;define ptr @addrspacecast_typed_to_opaque(i8 addrspace(1)* %a) {
-;  %b = addrspacecast i8 addrspace(1)* %a to ptr
-;  ret ptr %b
-;}
+define i8* @addrspacecast_opaque_to_typed(ptr addrspace(1) %a) {
+; CHECK-LABEL: @addrspacecast_opaque_to_typed(
+; CHECK-NEXT:    [[TMP1:%.*]] = bitcast ptr addrspace(1) [[A:%.*]] to i8 addrspace(1)*
+; CHECK-NEXT:    [[B:%.*]] = addrspacecast i8 addrspace(1)* [[TMP1]] to i8*
+; CHECK-NEXT:    ret i8* [[B]]
+;
+  %b = addrspacecast ptr addrspace(1) %a to i8*
+  ret i8* %b
+}
 
-;define i8* @addrspacecast_opaque_to_typed(ptr addrspace(1) %a) {
-;  %b = addrspacecast ptr addrspace(1) %a to i8*
-;  ret i8* %b
-;}
+define ptr addrspace(1) @bitcast_and_addrspacecast_eliminable(ptr %a) {
+; CHECK-LABEL: @bitcast_and_addrspacecast_eliminable(
+; CHECK-NEXT:    [[C:%.*]] = addrspacecast ptr [[A:%.*]] to ptr addrspace(1)
+; CHECK-NEXT:    ret ptr addrspace(1) [[C]]
+;
+  %b = bitcast ptr %a to i8*
+  %c = addrspacecast i8* %b to ptr addrspace(1)
+  ret ptr addrspace(1) %c
+}
 
 define ptr @gep_constexpr_1(ptr %a) {
 ; CHECK-LABEL: @gep_constexpr_1(