Extend conditions to include flambda2 (ocaml-flambda#115)

* Extend conditions to include flambda2.

* Make `[@unrolled]` flambda2-compatible.

* Add CR to enable test for flambda2 compilers.

ocaml/lambda/translattribute.ml

@@ -23,7 +23,7 @@ let is_inline_attribute = function
 
 let is_inlined_attribute = function
   | {txt=("inlined"|"ocaml.inlined")} -> true
-  | {txt=("unrolled"|"ocaml.unrolled")} when Config.flambda -> true
+  | {txt=("unrolled"|"ocaml.unrolled")} when Config.flambda || Config.flambda2 -> true
   | _ -> false
 
 let is_specialise_attribute = function

ocaml/lambda/translcore.ml

@@ -667,7 +667,7 @@ and transl_exp0 ~in_new_scope ~scopes e =
           ap_probe = Some {name};
         }
       in
-      begin match Config.flambda with
+      begin match Config.flambda || Config.flambda2 with
       | true ->
           Llet(Strict, Pgenval, funcid, Lfunction handler, Lapply app)
       | false ->

ocaml/parsing/builtin_attributes.ml

@@ -345,7 +345,7 @@ let nolabels_attribute attr =
 let flambda_o3_attribute attr =
   clflags_attribute_without_payload' attr
     ~name:"flambda_o3"
-    ~f:(fun () -> if Config.flambda then Clflags.set_o3 ())
+    ~f:(fun () -> if Config.flambda || Config.flambda2 then Clflags.set_o3 ())
 
 let inline_attribute attr =
   if String.equal attr.attr_name.txt "inline"

ocaml/testsuite/tests/float-unboxing/float_subst_boxed_number.ml

@@ -176,6 +176,7 @@ let () =
   check_noalloc "unbox only if useful" unbox_only_if_useful;
   check_noalloc "ignore useless args" ignore_useless_args;
 
+  (* CR xclerc for lukemaurer: enable these test for both flambda 1 and 2. *)
   if Config.flambda then begin
     check_noalloc "float and int32 record" unbox_record;
     check_noalloc "eliminate intermediate immutable float record"