AST: Promote BuiltinStoreRaw feature to baseline.

Author: tshortli

include/swift/Basic/Features.def

@@ -187,7 +187,7 @@ BASELINE_LANGUAGE_FEATURE(TypedThrows, 413, "Typed throws")
 CONDITIONALLY_SUPPRESSIBLE_LANGUAGE_FEATURE(OptionalIsolatedParameters, 420, "Optional isolated parameters")
 BASELINE_LANGUAGE_FEATURE(Extern, 0, "@_extern")
 BASELINE_LANGUAGE_FEATURE(ExpressionMacroDefaultArguments, 422, "Expression macro as caller-side default argument")
-LANGUAGE_FEATURE(BuiltinStoreRaw, 0, "Builtin.storeRaw")
+BASELINE_LANGUAGE_FEATURE(BuiltinStoreRaw, 0, "Builtin.storeRaw")
 BASELINE_LANGUAGE_FEATURE(BuiltinCreateTask, 0, "Builtin.createTask and Builtin.createDiscardingTask")
 SUPPRESSIBLE_LANGUAGE_FEATURE(AssociatedTypeImplements, 0, "@_implements on associated types")
 LANGUAGE_FEATURE(BuiltinAddressOfRawLayout, 0, "Builtin.addressOfRawLayout")

lib/AST/FeatureSet.cpp

@@ -175,7 +175,6 @@ static bool usesFeatureAssociatedTypeImplements(Decl *decl) {
   return isa<TypeDecl>(decl) && decl->getAttrs().hasAttribute<ImplementsAttr>();
 }
 
-UNINTERESTING_FEATURE(BuiltinStoreRaw)
 UNINTERESTING_FEATURE(BuiltinAddressOfRawLayout)
 
 // ----------------------------------------------------------------------------

stdlib/public/core/UnsafeRawPointer.swift

@@ -1404,11 +1404,7 @@ extension UnsafeMutableRawPointer {
   public func storeBytes<T: BitwiseCopyable>(
     of value: T, toByteOffset offset: Int = 0, as type: T.Type
   ) {
-#if $BuiltinStoreRaw
     Builtin.storeRaw(value, (self + offset)._rawValue)
-#else
-    fatalError("Unsupported swift compiler!")
-#endif
   }
 
   /// Stores the given value's bytes into raw memory at the specified offset.