Index: cfe/trunk/include/clang/Driver/CC1Options.td
===================================================================
--- cfe/trunk/include/clang/Driver/CC1Options.td
+++ cfe/trunk/include/clang/Driver/CC1Options.td
@@ -275,8 +275,6 @@
   HelpText<"Try to use a split stack if possible.">;
 def mno_zero_initialized_in_bss : Flag<["-"], "mno-zero-initialized-in-bss">,
   HelpText<"Do not put zero initialized data in the BSS">;
-def backend_option : Separate<["-"], "backend-option">,
-  HelpText<"Additional arguments to forward to LLVM backend (during code gen)">;
 def mregparm : Separate<["-"], "mregparm">,
   HelpText<"Limit the number of registers available for integer arguments">;
 def munwind_tables : Flag<["-"], "munwind-tables">,
Index: cfe/trunk/include/clang/Frontend/CodeGenOptions.h
===================================================================
--- cfe/trunk/include/clang/Frontend/CodeGenOptions.h
+++ cfe/trunk/include/clang/Frontend/CodeGenOptions.h
@@ -177,9 +177,6 @@
   /// function instead of to trap instructions.
   std::string TrapFuncName;
 
-  /// A list of command-line options to forward to the LLVM backend.
-  std::vector<std::string> BackendOptions;
-
   /// A list of dependent libraries.
   std::vector<std::string> DependentLibraries;
 
Index: cfe/trunk/lib/CodeGen/BackendUtil.cpp
===================================================================
--- cfe/trunk/lib/CodeGen/BackendUtil.cpp
+++ cfe/trunk/lib/CodeGen/BackendUtil.cpp
@@ -658,8 +658,6 @@
     BackendArgs.push_back("-limit-float-precision");
     BackendArgs.push_back(CodeGenOpts.LimitFloatPrecision.c_str());
   }
-  for (const std::string &BackendOption : CodeGenOpts.BackendOptions)
-    BackendArgs.push_back(BackendOption.c_str());
   BackendArgs.push_back(nullptr);
   llvm::cl::ParseCommandLineOptions(BackendArgs.size() - 1,
                                     BackendArgs.data());
Index: cfe/trunk/lib/Driver/ToolChains/Clang.cpp
===================================================================
--- cfe/trunk/lib/Driver/ToolChains/Clang.cpp
+++ cfe/trunk/lib/Driver/ToolChains/Clang.cpp
@@ -1350,7 +1350,7 @@
   // Forward the -mglobal-merge option for explicit control over the pass.
   if (Arg *A = Args.getLastArg(options::OPT_mglobal_merge,
                                options::OPT_mno_global_merge)) {
-    CmdArgs.push_back("-backend-option");
+    CmdArgs.push_back("-mllvm");
     if (A->getOption().matches(options::OPT_mno_global_merge))
       CmdArgs.push_back("-arm-global-merge=false");
     else
@@ -1464,21 +1464,21 @@
 
   if (Arg *A = Args.getLastArg(options::OPT_mfix_cortex_a53_835769,
                                options::OPT_mno_fix_cortex_a53_835769)) {
-    CmdArgs.push_back("-backend-option");
+    CmdArgs.push_back("-mllvm");
     if (A->getOption().matches(options::OPT_mfix_cortex_a53_835769))
       CmdArgs.push_back("-aarch64-fix-cortex-a53-835769=1");
     else
       CmdArgs.push_back("-aarch64-fix-cortex-a53-835769=0");
   } else if (Triple.isAndroid()) {
     // Enabled A53 errata (835769) workaround by default on android
-    CmdArgs.push_back("-backend-option");
+    CmdArgs.push_back("-mllvm");
     CmdArgs.push_back("-aarch64-fix-cortex-a53-835769=1");
   }
 
   // Forward the -mglobal-merge option for explicit control over the pass.
   if (Arg *A = Args.getLastArg(options::OPT_mglobal_merge,
                                options::OPT_mno_global_merge)) {
-    CmdArgs.push_back("-backend-option");
+    CmdArgs.push_back("-mllvm");
     if (A->getOption().matches(options::OPT_mno_global_merge))
       CmdArgs.push_back("-aarch64-enable-global-merge=false");
     else
@@ -3048,13 +3048,13 @@
   // Always enabled for SCE tuning.
   if (Args.hasArg(options::OPT_gdwarf_aranges) ||
       DebuggerTuning == llvm::DebuggerKind::SCE) {
-    CmdArgs.push_back("-backend-option");
+    CmdArgs.push_back("-mllvm");
     CmdArgs.push_back("-generate-arange-section");
   }
 
   if (Args.hasFlag(options::OPT_fdebug_types_section,
                    options::OPT_fno_debug_types_section, false)) {
-    CmdArgs.push_back("-backend-option");
+    CmdArgs.push_back("-mllvm");
     CmdArgs.push_back("-generate-type-units");
   }
 
@@ -4073,17 +4073,17 @@
   if (Arg *A = Args.getLastArg(options::OPT_mrestrict_it,
                                options::OPT_mno_restrict_it)) {
     if (A->getOption().matches(options::OPT_mrestrict_it)) {
-      CmdArgs.push_back("-backend-option");
+      CmdArgs.push_back("-mllvm");
       CmdArgs.push_back("-arm-restrict-it");
     } else {
-      CmdArgs.push_back("-backend-option");
+      CmdArgs.push_back("-mllvm");
       CmdArgs.push_back("-arm-no-restrict-it");
     }
   } else if (Triple.isOSWindows() &&
              (Triple.getArch() == llvm::Triple::arm ||
               Triple.getArch() == llvm::Triple::thumb)) {
     // Windows on ARM expects restricted IT blocks
-    CmdArgs.push_back("-backend-option");
+    CmdArgs.push_back("-mllvm");
     CmdArgs.push_back("-arm-restrict-it");
   }
 
Index: cfe/trunk/lib/Frontend/CompilerInvocation.cpp
===================================================================
--- cfe/trunk/lib/Frontend/CompilerInvocation.cpp
+++ cfe/trunk/lib/Frontend/CompilerInvocation.cpp
@@ -677,7 +677,6 @@
   Opts.ReciprocalMath = Args.hasArg(OPT_freciprocal_math);
   Opts.NoTrappingMath = Args.hasArg(OPT_fno_trapping_math);
   Opts.NoZeroInitializedInBSS = Args.hasArg(OPT_mno_zero_initialized_in_bss);
-  Opts.BackendOptions = Args.getAllArgValues(OPT_backend_option);
   Opts.NumRegisterParameters = getLastArgIntValue(Args, OPT_mregparm, 0, Diags);
   Opts.NoExecStack = Args.hasArg(OPT_mno_exec_stack);
   Opts.FatalWarnings = Args.hasArg(OPT_massembler_fatal_warnings);
Index: cfe/trunk/test/CodeGen/thinlto-backend-option.ll
===================================================================
--- cfe/trunk/test/CodeGen/thinlto-backend-option.ll
+++ cfe/trunk/test/CodeGen/thinlto-backend-option.ll
@@ -1,4 +1,4 @@
-; Test to ensure -backend-options work when invoking the ThinLTO backend path.
+; Test to ensure -mllvm work when invoking the ThinLTO backend path.
 
 ; This test uses a non-existent backend option to test that backend options are
 ; being parsed. While it's more important that the existing options are parsed
@@ -8,8 +8,8 @@
 
 ; RUN: %clang -flto=thin -c -o %t.o %s
 ; RUN: llvm-lto -thinlto -o %t %t.o
-; RUN: not %clang_cc1 -x ir %t.o -fthinlto-index=%t.thinlto.bc -backend-option -nonexistent -emit-obj -o /dev/null 2>&1 | FileCheck %s -check-prefix=UNKNOWN
-; UNKNOWN: clang: Unknown command line argument '-nonexistent'
+; RUN: not %clang_cc1 -x ir %t.o -fthinlto-index=%t.thinlto.bc -mllvm -nonexistent -emit-obj -o /dev/null 2>&1 | FileCheck %s -check-prefix=UNKNOWN
+; UNKNOWN: clang (LLVM option parsing): Unknown command line argument '-nonexistent'
 
 ; RUN: not %clang_cc1 -flto=thinfoo 2>&1 | FileCheck %s -check-prefix=INVALID
 ; INVALID: error: invalid value 'thinfoo' in '-flto=thinfoo'
Index: cfe/trunk/test/CodeGenCUDA/link-device-bitcode.cu
===================================================================
--- cfe/trunk/test/CodeGenCUDA/link-device-bitcode.cu
+++ cfe/trunk/test/CodeGenCUDA/link-device-bitcode.cu
@@ -31,7 +31,7 @@
 // Make sure NVVMReflect pass is enabled in NVPTX back-end.
 // RUN: %clang_cc1 -triple nvptx-unknown-cuda -fcuda-is-device \
 // RUN:    -mlink-cuda-bitcode %t.bc -S -o /dev/null %s \
-// RUN:    -backend-option -debug-pass=Structure 2>&1 \
+// RUN:    -mllvm -debug-pass=Structure 2>&1 \
 // RUN:    | FileCheck %s -check-prefix CHECK-REFLECT
 
 #include "Inputs/cuda.h"
Index: cfe/trunk/test/Driver/aarch64-fix-cortex-a53-835769.c
===================================================================
--- cfe/trunk/test/Driver/aarch64-fix-cortex-a53-835769.c
+++ cfe/trunk/test/Driver/aarch64-fix-cortex-a53-835769.c
@@ -8,6 +8,6 @@
 // RUN: %clang -target aarch64-android-eabi %s -### 2>&1 \
 // RUN:   | FileCheck --check-prefix=CHECK-YES %s
 
-// CHECK-DEF-NOT: "-backend-option" "-aarch64-fix-cortex-a53-835769"
-// CHECK-YES: "-backend-option" "-aarch64-fix-cortex-a53-835769=1"
-// CHECK-NO: "-backend-option" "-aarch64-fix-cortex-a53-835769=0"
+// CHECK-DEF-NOT: "-mllvm" "-aarch64-fix-cortex-a53-835769"
+// CHECK-YES: "-mllvm" "-aarch64-fix-cortex-a53-835769=1"
+// CHECK-NO: "-mllvm" "-aarch64-fix-cortex-a53-835769=0"
Index: cfe/trunk/test/Driver/apple-kext-mkernel.c
===================================================================
--- cfe/trunk/test/Driver/apple-kext-mkernel.c
+++ cfe/trunk/test/Driver/apple-kext-mkernel.c
@@ -26,7 +26,3 @@
 // RUN: %clang -target x86_64-apple-darwin10 \
 // RUN:   -Werror -fno-builtin -fno-exceptions -fno-common -fno-rtti \
 // RUN:   -mkernel -fsyntax-only %s
-
-// RUN: %clang -c %s -target armv7k-apple-watchos -fapple-kext -mwatchos-version-min=1.0.0 -### 2>&1 \
-// RUN:   | FileCheck %s --check-prefix=CHECK-WATCH
-// CHECK-WATCH-NOT: "-backend-option" "-arm-long-calls"
Index: cfe/trunk/test/Driver/arm-restrict-it.c
===================================================================
--- cfe/trunk/test/Driver/arm-restrict-it.c
+++ cfe/trunk/test/Driver/arm-restrict-it.c
@@ -4,7 +4,7 @@
 // RUN: %clang -target armv8a-none-gnueabi -mrestrict-it -### %s 2> %t
 // RUN: FileCheck --check-prefix=CHECK-RESTRICTED < %t %s
 
-// CHECK-RESTRICTED: "-backend-option" "-arm-restrict-it"
+// CHECK-RESTRICTED: "-mllvm" "-arm-restrict-it"
 
 // RUN: %clang -target arm-none-gnueabi -mno-restrict-it -### %s 2> %t
 // RUN: FileCheck --check-prefix=CHECK-NO-RESTRICTED < %t %s
@@ -12,4 +12,4 @@
 // RUN: %clang -target armv8a-none-gnueabi -mno-restrict-it -### %s 2> %t
 // RUN: FileCheck --check-prefix=CHECK-NO-RESTRICTED < %t %s
 
-// CHECK-NO-RESTRICTED: "-backend-option" "-arm-no-restrict-it"
+// CHECK-NO-RESTRICTED: "-mllvm" "-arm-no-restrict-it"
Index: cfe/trunk/test/Driver/debug-options.c
===================================================================
--- cfe/trunk/test/Driver/debug-options.c
+++ cfe/trunk/test/Driver/debug-options.c
@@ -225,9 +225,9 @@
 //
 // GARANGE: -generate-arange-section
 //
-// FDTS: "-backend-option" "-generate-type-units"
+// FDTS: "-mllvm" "-generate-type-units"
 //
-// NOFDTS-NOT: "-backend-option" "-generate-type-units"
+// NOFDTS-NOT: "-mllvm" "-generate-type-units"
 //
 // CI: "-dwarf-column-info"
 //
Index: cfe/trunk/test/Driver/mglobal-merge.c
===================================================================
--- cfe/trunk/test/Driver/mglobal-merge.c
+++ cfe/trunk/test/Driver/mglobal-merge.c
@@ -10,8 +10,8 @@
 // RUN:   -mno-global-merge
 // RUN: FileCheck --check-prefix=CHECK-NONE < %t %s
 
-// CHECK-NGM-ARM: "-backend-option" "-arm-global-merge=false"
-// CHECK-NGM-AARCH64: "-backend-option" "-aarch64-enable-global-merge=false"
+// CHECK-NGM-ARM: "-mllvm" "-arm-global-merge=false"
+// CHECK-NGM-AARCH64: "-mllvm" "-aarch64-enable-global-merge=false"
 
 // RUN: %clang -target armv7-unknown-unknown -### -fsyntax-only %s 2> %t \
 // RUN:   -mglobal-merge
@@ -25,8 +25,8 @@
 // RUN:   -mglobal-merge
 // RUN: FileCheck --check-prefix=CHECK-NONE < %t %s
 
-// CHECK-GM-ARM: "-backend-option" "-arm-global-merge=true"
-// CHECK-GM-AARCH64: "-backend-option" "-aarch64-enable-global-merge=true"
+// CHECK-GM-ARM: "-mllvm" "-arm-global-merge=true"
+// CHECK-GM-AARCH64: "-mllvm" "-aarch64-enable-global-merge=true"
 
 // RUN: %clang -target armv7-unknown-unknown -### -fsyntax-only %s 2> %t
 // RUN: FileCheck --check-prefix=CHECK-NONE < %t %s
Index: cfe/trunk/test/Driver/woa-restrict-it.c
===================================================================
--- cfe/trunk/test/Driver/woa-restrict-it.c
+++ cfe/trunk/test/Driver/woa-restrict-it.c
@@ -1,4 +1,4 @@
 // RUN: %clang -target armv7-windows -### %s 2>&1 | FileCheck %s
 
-// CHECK: "-backend-option" "-arm-restrict-it"
+// CHECK: "-mllvm" "-arm-restrict-it"
 
Index: cfe/trunk/test/Frontend/backend-option.c
===================================================================
--- cfe/trunk/test/Frontend/backend-option.c
+++ cfe/trunk/test/Frontend/backend-option.c
@@ -1,4 +0,0 @@
-// RUN: %clang_cc1 %s -emit-llvm -backend-option -time-passes -o - 2>&1 | FileCheck %s
-// RUN: %clang_cc1 %s -emit-llvm -backend-option -time-passes -o - -triple spir-unknown-unknown 2>&1 | FileCheck %s
-// CHECK: Pass execution timing report
-