diff --git a/clang/lib/Basic/Targets/WebAssembly.h b/clang/lib/Basic/Targets/WebAssembly.h
--- a/clang/lib/Basic/Targets/WebAssembly.h
+++ b/clang/lib/Basic/Targets/WebAssembly.h
@@ -38,6 +38,7 @@
   bool HasMutableGlobals = false;
   bool HasMultivalue = false;
   bool HasTailCall = false;
+  bool HasReferenceTypes = false;
 
 public:
   explicit WebAssemblyTargetInfo(const llvm::Triple &T, const TargetOptions &)
diff --git a/clang/lib/Basic/Targets/WebAssembly.cpp b/clang/lib/Basic/Targets/WebAssembly.cpp
--- a/clang/lib/Basic/Targets/WebAssembly.cpp
+++ b/clang/lib/Basic/Targets/WebAssembly.cpp
@@ -45,6 +45,7 @@
       .Case("mutable-globals", HasMutableGlobals)
       .Case("multivalue", HasMultivalue)
       .Case("tail-call", HasTailCall)
+      .Case("reference-types", HasReferenceTypes)
       .Default(false);
 }
 
@@ -80,6 +81,8 @@
     Builder.defineMacro("__wasm_multivalue__");
   if (HasTailCall)
     Builder.defineMacro("__wasm_tail_call__");
+  if (HasReferenceTypes)
+    Builder.defineMacro("__wasm_reference_types__");
 }
 
 void WebAssemblyTargetInfo::setSIMDLevel(llvm::StringMap<bool> &Features,
@@ -126,6 +129,8 @@
     Features["multivalue"] = true;
   if (HasTailCall)
     Features["tail-call"] = true;
+  if (HasReferenceTypes)
+    Features["reference-types"] = true;
 
   return TargetInfo::initFeatureMap(Features, Diags, CPU, FeaturesVec);
 }
@@ -213,6 +218,14 @@
       HasTailCall = false;
       continue;
     }
+    if (Feature == "+reference-types") {
+      HasReferenceTypes = true;
+      continue;
+    }
+    if (Feature == "-reference-types") {
+      HasReferenceTypes = false;
+      continue;
+    }
 
     Diags.Report(diag::err_opt_not_valid_with_opt)
         << Feature << "-target-feature";
diff --git a/clang/test/Preprocessor/wasm-target-features.c b/clang/test/Preprocessor/wasm-target-features.c
--- a/clang/test/Preprocessor/wasm-target-features.c
+++ b/clang/test/Preprocessor/wasm-target-features.c
@@ -96,6 +96,15 @@
 // RUN:   | FileCheck %s -check-prefix=TAIL-CALL
 //
 // TAIL-CALL:#define __wasm_tail_call__ 1{{$}}
+//
+// RUN: %clang -E -dM %s -o - 2>&1 \
+// RUN:     -target wasm32-unknown-unknown -mreference-types \
+// RUN:   | FileCheck %s -check-prefix=REFERENCE-TYPES
+// RUN: %clang -E -dM %s -o - 2>&1 \
+// RUN:     -target wasm64-unknown-unknown -mreference-types \
+// RUN:   | FileCheck %s -check-prefix=REFERENCE-TYPES
+//
+// REFERENCE-TYPES:#define __wasm_reference_types__ 1{{$}}
 
 // RUN: %clang -E -dM %s -o - 2>&1 \
 // RUN:     -target wasm32-unknown-unknown -mcpu=mvp \
@@ -114,6 +123,7 @@
 // MVP-NOT:#define __wasm_mutable_globals__
 // MVP-NOT:#define __wasm_multivalue__
 // MVP-NOT:#define __wasm_tail_call__
+// MVP-NOT:#define __wasm_reference_types__
 
 // RUN: %clang -E -dM %s -o - 2>&1 \
 // RUN:     -target wasm32-unknown-unknown -mcpu=bleeding-edge \
@@ -130,6 +140,7 @@
 // BLEEDING-EDGE-NOT:#define __wasm_unimplemented_simd128__ 1{{$}}
 // BLEEDING-EDGE-NOT:#define __wasm_multivalue__ 1{{$}}
 // BLEEDING-EDGE-NOT:#define __wasm_tail_call__ 1{{$}}
+// BLEEDING-EDGE-NOT:#define __wasm_reference_types__ 1{{$}}
 
 // RUN: %clang -E -dM %s -o - 2>&1 \
 // RUN:     -target wasm32-unknown-unknown -mcpu=bleeding-edge -mno-simd128 \
diff --git a/llvm/lib/Target/WebAssembly/WebAssembly.td b/llvm/lib/Target/WebAssembly/WebAssembly.td
--- a/llvm/lib/Target/WebAssembly/WebAssembly.td
+++ b/llvm/lib/Target/WebAssembly/WebAssembly.td
@@ -66,6 +66,10 @@
       SubtargetFeature<"mutable-globals", "HasMutableGlobals", "true",
                        "Enable mutable globals">;
 
+def FeatureReferenceTypes :
+      SubtargetFeature<"reference-types", "HasReferenceTypes", "true",
+                       "Enable reference types">;
+
 //===----------------------------------------------------------------------===//
 // Architectures.
 //===----------------------------------------------------------------------===//
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.td
--- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.td
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrInfo.td
@@ -62,6 +62,10 @@
     Predicate<"Subtarget->hasBulkMemory()">,
     AssemblerPredicate<"FeatureBulkMemory", "bulk-memory">;
 
+def HasReferenceTypes :
+    Predicate<"Subtarget->hasReferenceTypes()">,
+    AssemblerPredicate<"FeatureReferenceTypes", "reference-types">;
+
 //===----------------------------------------------------------------------===//
 // WebAssembly-specific DAG Node Types.
 //===----------------------------------------------------------------------===//
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblySubtarget.h b/llvm/lib/Target/WebAssembly/WebAssemblySubtarget.h
--- a/llvm/lib/Target/WebAssembly/WebAssemblySubtarget.h
+++ b/llvm/lib/Target/WebAssembly/WebAssemblySubtarget.h
@@ -47,6 +47,7 @@
   bool HasMultivalue = false;
   bool HasMutableGlobals = false;
   bool HasTailCall = false;
+  bool HasReferenceTypes = false;
 
   /// String name of used CPU.
   std::string CPUString;
@@ -104,6 +105,7 @@
   bool hasMultivalue() const { return HasMultivalue; }
   bool hasMutableGlobals() const { return HasMutableGlobals; }
   bool hasTailCall() const { return HasTailCall; }
+  bool hasReferenceTypes() const { return HasReferenceTypes; }
 
   /// Parses features string setting specified subtarget options. Definition of
   /// function is auto generated by tblgen.
diff --git a/llvm/test/CodeGen/WebAssembly/reference-types.ll b/llvm/test/CodeGen/WebAssembly/reference-types.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/WebAssembly/reference-types.ll
@@ -0,0 +1,12 @@
+; RUN: llc < %s -asm-verbose=false -verify-machineinstrs -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -wasm-keep-registers -mattr=+reference-types | FileCheck %s
+
+; This currently only tests if the command line argument for reference types
+; feature is accepted by llc.
+
+target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128"
+target triple = "wasm32-unknown-unknown"
+
+; CHECK-LABEL: dummy
+define void @dummy() {
+  ret void
+}