diff --git a/clang/include/clang/Basic/TargetCXXABI.h b/clang/include/clang/Basic/TargetCXXABI.h
--- a/clang/include/clang/Basic/TargetCXXABI.h
+++ b/clang/include/clang/Basic/TargetCXXABI.h
@@ -64,6 +64,12 @@
     return getABIMap().find(Name) != getABIMap().end();
   }
 
+  // Return true if this target should use the relative vtables C++ ABI by
+  // default.
+  static bool usesRelativeVTables(const llvm::Triple &T) {
+    return T.isOSFuchsia();
+  }
+
   /// A bogus initialization of the platform ABI.
   TargetCXXABI() : TheKind(GenericItanium) {}
 
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -1932,10 +1932,14 @@
   BothFlags<[CC1Option]>>,
   Group<f_clang_Group>;
 
-defm experimental_relative_cxx_abi_vtables : BoolFOption<"experimental-relative-c++-abi-vtables",
-  LangOpts<"RelativeCXXABIVTables">, DefaultFalse,
-  PosFlag<SetTrue, [], "Use">, NegFlag<SetFalse, [], "Do not use">,
-  BothFlags<[CC1Option], " the experimental C++ class ABI for classes with virtual tables">>;
+def fexperimental_relative_cxx_abi_vtables :
+  Flag<["-"], "fexperimental-relative-c++-abi-vtables">,
+  Group<f_clang_Group>, Flags<[CC1Option]>,
+  HelpText<"Use the experimental C++ class ABI for classes with virtual tables">;
+def fno_experimental_relative_cxx_abi_vtables :
+  Flag<["-"], "fno-experimental-relative-c++-abi-vtables">,
+  Group<f_clang_Group>, Flags<[CC1Option]>,
+  HelpText<"Do not use the experimental C++ class ABI for classes with virtual tables">;
 
 def fcxx_abi_EQ : Joined<["-"], "fc++-abi=">,
                   Group<f_clang_Group>, Flags<[CC1Option]>,
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -5386,6 +5386,9 @@
   if (Arg *A = Args.getLastArg(options::OPT_fcxx_abi_EQ))
     A->render(Args, CmdArgs);
 
+  Args.AddLastArg(CmdArgs, options::OPT_fexperimental_relative_cxx_abi_vtables,
+                  options::OPT_fno_experimental_relative_cxx_abi_vtables);
+
   // Handle -{std, ansi, trigraphs} -- take the last of -{std, ansi}
   // (-ansi is equivalent to -std=c89 or -std=c++98).
   //
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -3529,6 +3529,11 @@
   if (Opts.CXXABI)
     GenerateArg(Args, OPT_fcxx_abi_EQ, TargetCXXABI::getSpelling(*Opts.CXXABI),
                 SA);
+
+  if (Opts.RelativeCXXABIVTables)
+    GenerateArg(Args, OPT_fexperimental_relative_cxx_abi_vtables, SA);
+  else
+    GenerateArg(Args, OPT_fno_experimental_relative_cxx_abi_vtables, SA);
 }
 
 bool CompilerInvocation::ParseLangArgs(LangOptions &Opts, ArgList &Args,
@@ -4039,6 +4044,11 @@
     }
   }
 
+  Opts.RelativeCXXABIVTables =
+      Args.hasFlag(options::OPT_fexperimental_relative_cxx_abi_vtables,
+                   options::OPT_fno_experimental_relative_cxx_abi_vtables,
+                   TargetCXXABI::usesRelativeVTables(T));
+
   return Diags.getNumErrors() == NumErrorsBefore;
 }
 
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/available_externally-vtable.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/available_externally-vtable.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/available_externally-vtable.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/available_externally-vtable.cpp
@@ -2,7 +2,7 @@
 // We check this specifically under the legacy pass manager because the new pass
 // manager seems to remove available_externally vtables from the IR entirely.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fno-experimental-new-pass-manager | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fno-experimental-new-pass-manager | FileCheck %s
 
 // The VTable for A is available_externally, meaning it can have a definition in
 // IR, but is never emitted in this compilation unit. Because it won't be
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/child-inheritted-from-parent-in-comdat.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/child-inheritted-from-parent-in-comdat.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/child-inheritted-from-parent-in-comdat.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/child-inheritted-from-parent-in-comdat.cpp
@@ -1,7 +1,7 @@
 // Cross comdat example
 // Parent VTable is in a comdat section.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s
 
 // The inline function is emitted in each module with the same comdat
 // CHECK: $_ZTS1A = comdat any
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/child-vtable-in-comdat.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/child-vtable-in-comdat.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/child-vtable-in-comdat.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/child-vtable-in-comdat.cpp
@@ -1,7 +1,7 @@
 // Cross comdat example
 // Child VTable is in a comdat section.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm | FileCheck %s
 
 // A comdat is emitted for B but not A
 // CHECK-DAG: $_ZTV1B = comdat any
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/cross-translation-unit-1.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/cross-translation-unit-1.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/cross-translation-unit-1.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/cross-translation-unit-1.cpp
@@ -1,7 +1,7 @@
 // Check the vtable layout for classes with key functions defined in different
 // translation units. This TU only manifests the vtable for A.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s
 
 #include "cross-tu-header.h"
 
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/cross-translation-unit-2.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/cross-translation-unit-2.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/cross-translation-unit-2.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/cross-translation-unit-2.cpp
@@ -1,7 +1,7 @@
 // Check the vtable layout for classes with key functions defined in different
 // translation units. This TU manifests the vtable for B.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s
 
 #include "cross-tu-header.h"
 
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/diamond-inheritance.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/diamond-inheritance.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/diamond-inheritance.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/diamond-inheritance.cpp
@@ -1,7 +1,7 @@
 // Diamond inheritance.
 // A more complicated multiple inheritance example that includes longer chain of inheritance and a common ancestor.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s
 
 // CHECK-DAG: %class.B = type { %class.A }
 // CHECK-DAG: %class.A = type { i32 (...)** }
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/diamond-virtual-inheritance.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/diamond-virtual-inheritance.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/diamond-virtual-inheritance.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/diamond-virtual-inheritance.cpp
@@ -1,7 +1,7 @@
 // Diamond virtual inheritance.
 // This should cover virtual inheritance, construction vtables, and VTTs.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s
 
 // Class A contains a vtable ptr, then int, then padding
 // CHECK-DAG: %class.B = type { i32 (...)**, %class.A.base }
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/dynamic-cast.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/dynamic-cast.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/dynamic-cast.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/dynamic-cast.cpp
@@ -1,7 +1,7 @@
 // dynamic_cast
 // Ensure that dynamic casting works normally
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O3 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O3 -S -o - -emit-llvm | FileCheck %s
 
 // CHECK:      define{{.*}} %class.A* @_Z6upcastP1B(%class.B* readnone %b) local_unnamed_addr
 // CHECK-NEXT: entry:
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/inheritted-virtual-function.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/inheritted-virtual-function.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/inheritted-virtual-function.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/inheritted-virtual-function.cpp
@@ -1,7 +1,7 @@
 // Check the layout of the vtable for a child class that inherits a virtual
 // function but does not override it.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s
 
 class A {
 public:
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/inlined-key-function.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/inlined-key-function.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/inlined-key-function.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/inlined-key-function.cpp
@@ -1,7 +1,7 @@
 // Inline comdat method definition example.
 // The VTable is in a comdat and defined anywhere the inline definition is.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm | FileCheck %s
 
 // CHECK: $_ZTV1A = comdat any
 // CHECK: $_ZTS1A = comdat any
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/member-function-pointer.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/member-function-pointer.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/member-function-pointer.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/member-function-pointer.cpp
@@ -1,6 +1,6 @@
 // Member pointer to virtual function.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O3 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O3 -S -o - -emit-llvm | FileCheck %s
 
 // CHECK:      define{{.*}} void @_Z4funcP1AMS_FvvE(%class.A* %a, [2 x i64] %fn.coerce) local_unnamed_addr
 // CHECK-NEXT: entry:
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/multiple-inheritance.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/multiple-inheritance.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/multiple-inheritance.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/multiple-inheritance.cpp
@@ -1,6 +1,6 @@
 // Multiple inheritance.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s
 
 // CHECK: %class.C = type { %class.A, %class.B }
 // CHECK: %class.A = type { i32 (...)** }
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/no-alias-when-dso-local.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/no-alias-when-dso-local.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/no-alias-when-dso-local.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/no-alias-when-dso-local.cpp
@@ -1,8 +1,8 @@
 // Check that no alias is emitted when the vtable is already dso_local. This can
 // happen if the class is hidden.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck %s --check-prefix=DEFAULT-VIS
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fvisibility hidden | FileCheck %s --check-prefix=HIDDEN-VIS
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s --check-prefix=DEFAULT-VIS
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm -fvisibility hidden | FileCheck %s --check-prefix=HIDDEN-VIS
 
 // DEFAULT-VIS: @_ZTV1A.local = private unnamed_addr constant
 // DEFAULT-VIS: @_ZTV1A ={{.*}} unnamed_addr alias { [3 x i32] }, { [3 x i32] }* @_ZTV1A.local
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/override-pure-virtual-method.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/override-pure-virtual-method.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/override-pure-virtual-method.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/override-pure-virtual-method.cpp
@@ -2,7 +2,7 @@
 // We instead emit zero for the pure virtual function component. See PR43094 for
 // details.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s
 
 // CHECK: @_ZTV1A.local = private unnamed_addr constant { [4 x i32] } { [4 x i32] [i32 0, i32 trunc (i64 sub (i64 ptrtoint ({ i8*, i8* }** @_ZTI1A.rtti_proxy to i64), i64 ptrtoint (i32* getelementptr inbounds ({ [4 x i32] }, { [4 x i32] }* @_ZTV1A.local, i32 0, i32 0, i32 2) to i64)) to i32), i32 0, i32 trunc (i64 sub (i64 ptrtoint (void (%class.A*)* dso_local_equivalent @_ZN1A3barEv to i64), i64 ptrtoint (i32* getelementptr inbounds ({ [4 x i32] }, { [4 x i32] }* @_ZTV1A.local, i32 0, i32 0, i32 2) to i64)) to i32)] }, align 4
 
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/overriden-virtual-function.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/overriden-virtual-function.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/overriden-virtual-function.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/overriden-virtual-function.cpp
@@ -1,7 +1,7 @@
 // Check the layout of the vtable for a child class that inherits a virtual
 // function but does override it.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s
 
 // CHECK: @_ZTV1B.local = private unnamed_addr constant { [4 x i32] } { [4 x i32] [i32 0, i32 trunc (i64 sub (i64 ptrtoint ({ i8*, i8*, i8* }** @_ZTI1B.rtti_proxy to i64), i64 ptrtoint (i32* getelementptr inbounds ({ [4 x i32] }, { [4 x i32] }* @_ZTV1B.local, i32 0, i32 0, i32 2) to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint (void (%class.B*)* dso_local_equivalent @_ZN1B3fooEv to i64), i64 ptrtoint (i32* getelementptr inbounds ({ [4 x i32] }, { [4 x i32] }* @_ZTV1B.local, i32 0, i32 0, i32 2) to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint (void (%class.B*)* dso_local_equivalent @_ZN1B3barEv to i64), i64 ptrtoint (i32* getelementptr inbounds ({ [4 x i32] }, { [4 x i32] }* @_ZTV1B.local, i32 0, i32 0, i32 2) to i64)) to i32)] }, align 4
 
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/relative-vtables-flag.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/relative-vtables-flag.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/relative-vtables-flag.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/relative-vtables-flag.cpp
@@ -3,9 +3,8 @@
 // of a soft incremental rollout. This ABI should only be used if the flag for
 // it is passed on Fuchsia.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck --check-prefix=RELATIVE-ABI %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck --check-prefix=RELATIVE-ABI %s
 // RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm -fno-experimental-relative-c++-abi-vtables | FileCheck --check-prefix=DEFAULT-ABI %s
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm | FileCheck --check-prefix=DEFAULT-ABI %s
 
 // VTable contains offsets and references to the hidden symbols
 // RELATIVE-ABI: @_ZTV1A.local = private unnamed_addr constant { [3 x i32] } { [3 x i32] [i32 0, i32 trunc (i64 sub (i64 ptrtoint ({ i8*, i8* }** @_ZTI1A.rtti_proxy to i64), i64 ptrtoint (i32* getelementptr inbounds ({ [3 x i32] }, { [3 x i32] }* @_ZTV1A.local, i32 0, i32 0, i32 2) to i64)) to i32), i32 trunc (i64 sub (i64 ptrtoint (void (%class.A*)* dso_local_equivalent @_ZN1A3fooEv to i64), i64 ptrtoint (i32* getelementptr inbounds ({ [3 x i32] }, { [3 x i32] }* @_ZTV1A.local, i32 0, i32 0, i32 2) to i64)) to i32)] }, align 4
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/simple-vtable-definition.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/simple-vtable-definition.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/simple-vtable-definition.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/simple-vtable-definition.cpp
@@ -1,6 +1,6 @@
 // Check the layout of the vtable for a normal class.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables -fhalf-no-semantic-interposition | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fhalf-no-semantic-interposition | FileCheck %s
 
 // We should be emitting comdats for each of the virtual function RTTI proxies
 // CHECK: $_ZTI1A.rtti_proxy = comdat any
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/thunk-mangling.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/thunk-mangling.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/thunk-mangling.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/thunk-mangling.cpp
@@ -5,7 +5,7 @@
 // Running that linked binary still won't work since we're using conflicting
 // ABIs, but we should still be able to link.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O1 -S -o - -emit-llvm | FileCheck %s
 
 // This would be normally n24 (3 ptr widths) but is 12 since the vtable is
 // entierely made of i32s now.
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/type-info.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/type-info.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/type-info.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/type-info.cpp
@@ -1,6 +1,6 @@
 // Check typeid() + type_info
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O3 -S -o - -emit-llvm -fcxx-exceptions -fexceptions -fexperimental-relative-c++-abi-vtables | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O3 -S -o - -emit-llvm -fcxx-exceptions -fexceptions | FileCheck %s
 
 // CHECK: %class.A = type { i32 (...)** }
 // CHECK: %class.B = type { %class.A }
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/vbase-offset.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/vbase-offset.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/vbase-offset.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/vbase-offset.cpp
@@ -1,7 +1,7 @@
 // Check that the pointer adjustment from the virtual base offset is loaded as a
 // 32-bit int.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm | FileCheck %s
 
 // CHECK-LABEL: @_ZTv0_n12_N7Derived1fEi(
 // CHECK-NEXT:  entry:
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/virtual-function-call.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/virtual-function-call.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/virtual-function-call.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/virtual-function-call.cpp
@@ -1,6 +1,6 @@
 // Check that we call llvm.load.relative() on a vtable function call.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O3 -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -O3 -S -o - -emit-llvm | FileCheck %s
 
 // CHECK:      define{{.*}} void @_Z5A_fooP1A(%class.A* %a) local_unnamed_addr
 // CHECK-NEXT: entry:
diff --git a/clang/test/CodeGenCXX/RelativeVTablesABI/vtable-hidden-when-in-comdat.cpp b/clang/test/CodeGenCXX/RelativeVTablesABI/vtable-hidden-when-in-comdat.cpp
--- a/clang/test/CodeGenCXX/RelativeVTablesABI/vtable-hidden-when-in-comdat.cpp
+++ b/clang/test/CodeGenCXX/RelativeVTablesABI/vtable-hidden-when-in-comdat.cpp
@@ -2,7 +2,7 @@
 // is not dso_local. The vtable will need to be hidden and not private so it can
 // be used as acomdat key signature.
 
-// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm -fexperimental-relative-c++-abi-vtables | FileCheck %s
+// RUN: %clang_cc1 %s -triple=aarch64-unknown-fuchsia -S -o - -emit-llvm | FileCheck %s
 
 // CHECK: @_ZTV1B.local = linkonce_odr hidden unnamed_addr constant
 // CHECK: @_ZTV1B = linkonce_odr unnamed_addr alias { [3 x i32] }, { [3 x i32] }* @_ZTV1B.local
diff --git a/clang/test/CodeGenCXX/constructor-destructor-return-this.cpp b/clang/test/CodeGenCXX/constructor-destructor-return-this.cpp
--- a/clang/test/CodeGenCXX/constructor-destructor-return-this.cpp
+++ b/clang/test/CodeGenCXX/constructor-destructor-return-this.cpp
@@ -151,8 +151,10 @@
 
 // Verify that virtual calls to destructors are not marked with a 'returned'
 // this parameter at the call site...
-// CHECKARM,CHECKFUCHSIA: [[VFN:%.*]] = getelementptr inbounds %class.E* (%class.E*)*, %class.E* (%class.E*)**
-// CHECKARM,CHECKFUCHSIA: [[THUNK:%.*]] = load %class.E* (%class.E*)*, %class.E* (%class.E*)** [[VFN]]
+// CHECKARM: [[VFN:%.*]] = getelementptr inbounds %class.E* (%class.E*)*, %class.E* (%class.E*)**
+// CHECKARM: [[THUNK:%.*]] = load %class.E* (%class.E*)*, %class.E* (%class.E*)** [[VFN]]
+// CHECKFUCHSIA: [[THUNK_I8:%.*]] = call i8* @llvm.load.relative.i32(i8* {{.*}}, i32 0)
+// CHECKFUCHSIA: [[THUNK:%.*]] = bitcast i8* [[THUNK_I8]] to %class.E* (%class.E*)*
 // CHECKARM,CHECKFUCHSIA: call %class.E* [[THUNK]](%class.E* {{[^,]*}} %
 
 // ...but static calls create declarations with 'returned' this