flambda-backend: Add config variables flambda_backend, flambda2 and probes (#99)

* Add config variable flambda_backend=true

* Add flambda2 and probes config vars

* probes

Co-authored-by: Xavier Clerc <[email protected]>

* Expose flambda_backend in config.mli

* Update ocaml/utils/config.mlp

Co-authored-by: Xavier Clerc <[email protected]>

Co-authored-by: Xavier Clerc <[email protected]>

Author: mshinwell

utils/config.mli

@@ -200,6 +200,10 @@ val flambda : bool
 val flambda2 : bool
 (** Whether the compiler was configured for Flambda 2 *)
 
+val flambda_backend : bool
+(** [true] if the compiler was built in a Flambda backend repo, [false] if
+    the compiler was built as per upstream. *)
+
 val with_flambda_invariants : bool
 (** Whether the invariants checks for flambda are enabled *)
 

utils/config.mlp

@@ -76,6 +76,9 @@ let mkdll, mkexe, mkmaindll =
 let flambda = %%FLAMBDA%%
 let flambda2 = %%FLAMBDA2%%
 let with_flambda_invariants = %%WITH_FLAMBDA_INVARIANTS%%
+
+let flambda_backend = true
+
 let safe_string = %%FORCE_SAFE_STRING%%
 let default_safe_string = %%DEFAULT_SAFE_STRING%%
 let windows_unicode = %%WINDOWS_UNICODE%% != 0
@@ -193,6 +196,7 @@ let configuration_variables =
   p "host" host;
   p "target" target;
   p_bool "flambda" flambda;
+  p_bool "flambda2" flambda2;
   p_bool "safe_string" safe_string;
   p_bool "default_safe_string" default_safe_string;
   p_bool "flat_float_array" flat_float_array;
@@ -212,6 +216,9 @@ let configuration_variables =
   p "cmxs_magic_number" cmxs_magic_number;
   p "cmt_magic_number" cmt_magic_number;
   p "linear_magic_number" linear_magic_number;
+
+  p_bool "flambda_backend" flambda_backend;
+  p_bool "probes" probes;
 ]
 
 let print_config_value oc = function