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
@@ -6736,6 +6736,8 @@
 
 def dxc_Group : OptionGroup<"<clang-dxc options>">, Flags<[DXCOption]>,
   HelpText<"dxc compatibility options">;
+class DXCFlag<string name> : Option<["/", "-"], name, KIND_FLAG>,
+  Group<dxc_Group>, Flags<[DXCOption, NoXarchOption]>;
 class DXCJoinedOrSeparate<string name> : Option<["/", "-"], name,
   KIND_JOINED_OR_SEPARATE>, Group<dxc_Group>, Flags<[DXCOption, NoXarchOption]>;
 
@@ -6760,3 +6762,8 @@
          "lib_6_3, lib_6_4, lib_6_5, lib_6_6, lib_6_7, lib_6_x,"
          "ms_6_5, ms_6_6, ms_6_7,"
          "as_6_5, as_6_6, as_6_7">;
+def enable_16bit_types : DXCFlag<"enable-16bit-types">, Alias<fnative_half_type>,
+  HelpText<"Enable 16-bit types and disable min precision types."
+           "Available in HLSL 2018 and shader model 6.2.">;
+def fcgl : DXCFlag<"fcgl">,
+  HelpText<"Generate high-level code only. Without any dxil related passes.">;
diff --git a/clang/lib/Basic/LangOptions.cpp b/clang/lib/Basic/LangOptions.cpp
--- a/clang/lib/Basic/LangOptions.cpp
+++ b/clang/lib/Basic/LangOptions.cpp
@@ -194,8 +194,8 @@
   // OpenCL, C++ and C2x have bool, true, false keywords.
   Opts.Bool = Opts.OpenCL || Opts.CPlusPlus || Opts.C2x;
 
-  // OpenCL has half keyword
-  Opts.Half = Opts.OpenCL;
+  // OpenCL and HLSL have half keyword
+  Opts.Half = Opts.OpenCL || Opts.HLSL;
 }
 
 FPOptions FPOptions::defaultWithoutTrailingStorage(const LangOptions &LO) {
diff --git a/clang/lib/Basic/Targets/DirectX.h b/clang/lib/Basic/Targets/DirectX.h
--- a/clang/lib/Basic/Targets/DirectX.h
+++ b/clang/lib/Basic/Targets/DirectX.h
@@ -58,7 +58,7 @@
     resetDataLayout("e-m:e-p:32:32-i1:32-i8:8-i16:16-i32:32-i64:64-f16:16-f32:"
                     "32-f64:64-n8:16:32:64");
   }
-
+  bool useFP16ConversionIntrinsics() const override { return false; }
   void getTargetDefines(const LangOptions &Opts,
                         MacroBuilder &Builder) const override;
 
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
@@ -3470,11 +3470,14 @@
 
 static void RenderHLSLOptions(const ArgList &Args, ArgStringList &CmdArgs,
                               types::ID InputType) {
-  const unsigned ForwardedArguments[] = {options::OPT_dxil_validator_version};
+  const unsigned ForwardedArguments[] = {options::OPT_dxil_validator_version,
+                                         options::OPT_S, options::OPT_emit_llvm,
+                                         options::OPT_fnative_half_type};
 
   for (const auto &Arg : ForwardedArguments)
     if (const auto *A = Args.getLastArg(Arg))
       A->renderAsInput(Args, CmdArgs);
+  CmdArgs.push_back("-fallow-half-arguments-and-returns");
 }
 
 static void RenderARCMigrateToolOptions(const Driver &D, const ArgList &Args,
diff --git a/clang/lib/Driver/ToolChains/HLSL.cpp b/clang/lib/Driver/ToolChains/HLSL.cpp
--- a/clang/lib/Driver/ToolChains/HLSL.cpp
+++ b/clang/lib/Driver/ToolChains/HLSL.cpp
@@ -169,6 +169,13 @@
       if (!isLegalValidatorVersion(ValVerStr, getDriver()))
         continue;
     }
+    if (A->getOption().getID() == options::OPT_fcgl) {
+      // Translate fcgl into -S -emit-llvm.
+      DAL->AddFlagArg(nullptr, Opts.getOption(options::OPT_S));
+      DAL->AddFlagArg(nullptr, Opts.getOption(options::OPT_emit_llvm));
+      A->claim();
+      continue;
+    }
     DAL->append(A);
   }
   // Add default validator version if not set.
@@ -179,5 +186,7 @@
                         Opts.getOption(options::OPT_dxil_validator_version),
                         DefaultValidatorVer);
   }
+  // FIXME: add validation for enable_16bit_types should be after HLSL 2018 and
+  // shader model 6.2.
   return DAL;
 }
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -1509,7 +1509,13 @@
         << "_Float16";
     Result = Context.Float16Ty;
     break;
-  case DeclSpec::TST_half:    Result = Context.HalfTy; break;
+  case DeclSpec::TST_half:
+    // For HLSL, when not enable native half type, half will be treat as float.
+    if (S.getLangOpts().HLSL && !S.getLangOpts().NativeHalfType)
+      Result = Context.FloatTy;
+    else
+      Result = Context.HalfTy;
+    break;
   case DeclSpec::TST_BFloat16:
     if (!S.Context.getTargetInfo().hasBFloat16Type())
       S.Diag(DS.getTypeSpecTypeLoc(), diag::err_type_unsupported)
diff --git a/clang/test/CodeGenHLSL/half.hlsl b/clang/test/CodeGenHLSL/half.hlsl
new file mode 100644
--- /dev/null
+++ b/clang/test/CodeGenHLSL/half.hlsl
@@ -0,0 +1,15 @@
+// RUN: %clang_dxc -Tlib_6_7 -fcgl  -Fo - %s | FileCheck %s --check-prefix=FLOAT
+// RUN: %clang_dxc -Tlib_6_7 -enable-16bit-types -fcgl  -Fo - %s | FileCheck %s --check-prefix=HALF
+
+// Make sure use float when not enable-16bit-types.
+// FLOAT:define {{.*}}float @_Z3fooff(float{{[^,]+}}, float{{[^,)]+}})
+// FLOAT-NOT:half
+// FLOAT:ret float %
+
+// Make sure use half when enable-16bit-types.
+// HALF:define {{.*}}half @_Z3fooDhDh(half{{[^,]+}}, half{{[^,)]+}})
+// HALF-NOT:float
+// HALF:ret half %
+half foo(half a, half b) {
+  return a+b;
+}