Re-enable reference types by default

Now that we are about to upgrade emsdk's default node to v18.20.3
(emscripten-core/emsdk#1387), we can re-enable
reference-types by default again. This effectively reverts llvm#90792.

Author: aheejin

clang/docs/ReleaseNotes.rst

@@ -881,10 +881,10 @@ AIX Support
 WebAssembly Support
 ^^^^^^^^^^^^^^^^^^^
 
-The -mcpu=generic configuration now enables multivalue feature, which is
-standardized and available in all major engines. Enabling multivalue here only
-enables the language feature but does not turn on the multivalue ABI (this
-enables non-ABI uses of multivalue, like exnref).
+The -mcpu=generic configuration now enables multivalue and reference-types.These
+proposals are standardized and available in all major engines. Enabling
+multivalue here only enables the language feature but does not turn on the
+multivalue ABI (this enables non-ABI uses of multivalue, like exnref).
 
 AVR Support
 ^^^^^^^^^^^

clang/lib/Basic/Targets/WebAssembly.cpp

@@ -153,6 +153,7 @@ bool WebAssemblyTargetInfo::initFeatureMap(
   auto addGenericFeatures = [&]() {
     Features["multivalue"] = true;
     Features["mutable-globals"] = true;
+    Features["reference-types"] = true;
     Features["sign-ext"] = true;
   };
   auto addBleedingEdgeFeatures = [&]() {
@@ -164,7 +165,6 @@ bool WebAssemblyTargetInfo::initFeatureMap(
     Features["half-precision"] = true;
     Features["multimemory"] = true;
     Features["nontrapping-fptoint"] = true;
-    Features["reference-types"] = true;
     Features["tail-call"] = true;
     setSIMDLevel(Features, RelaxedSIMD, true);
   };

clang/test/Preprocessor/wasm-target-features.c

@@ -164,6 +164,7 @@
 //
 // GENERIC-INCLUDE-DAG: #define __wasm_multivalue__ 1{{$}}
 // GENERIC-INCLUDE-DAG: #define __wasm_mutable_globals__ 1{{$}}
+// GENERIC-INCLUDE-DAG: #define __wasm_reference_types__ 1{{$}}
 // GENERIC-INCLUDE-DAG: #define __wasm_sign_ext__ 1{{$}}
 //
 // RUN: %clang -E -dM %s -o - 2>&1 \
@@ -180,7 +181,6 @@
 // GENERIC-NOT: #define __wasm_half_precision__ 1{{$}}
 // GENERIC-NOT: #define __wasm_multimemory__ 1{{$}}
 // GENERIC-NOT: #define __wasm_nontrapping_fptoint__ 1{{$}}
-// GENERIC-NOT: #define __wasm_reference_types__ 1{{$}}
 // GENERIC-NOT: #define __wasm_relaxed_simd__ 1{{$}}
 // GENERIC-NOT: #define __wasm_simd128__ 1{{$}}
 // GENERIC-NOT: #define __wasm_tail_call__ 1{{$}}