Rewrite inline pass

- We are a lot more aggressive at inlining functor-like functions, since
this may enable further optimizations.
- We are more cautious at inlining nested functions, since this can result
in memory leaks.
- We inline a larger class of small functions

Author: vouillon

compiler/lib/config.ml

@@ -135,7 +135,7 @@ module Param = struct
     p ~name:"switch_size" ~desc:"set the maximum number of case in a switch" (int 60)
 
   let inlining_limit =
-    p ~name:"inlining-limit" ~desc:"set the size limit for inlining" (int 200)
+    p ~name:"inlining-limit" ~desc:"set the size limit for inlining" (int 150)
 
   let tailcall_max_depth =
     p

compiler/lib/driver.ml

@@ -54,12 +54,12 @@ let deadcode p =
   let r, live_vars = deadcode' p in
   Deadcode.remove_empty_blocks ~live_vars r
 
-let inline p =
+let inline aggressive p =
   if Config.Flag.inline () && Config.Flag.deadcode ()
   then (
     let p, live_vars = deadcode' p in
     if debug () then Format.eprintf "Inlining...@.";
-    Inline.f p live_vars)
+    Inline.f ~aggressive p live_vars)
   else p
 
 let specialize_1 (p, info) =
@@ -158,42 +158,44 @@ let identity x = x
 
 (* o1 *)
 
-let o1 : 'a -> 'a =
+let round opt : 'a -> 'a =
   print
   +> tailcall
   +> flow_simple (* flow simple to keep information for future tailcall opt *)
   +> specialize'
   +> eval
-  +> inline (* inlining may reveal new tailcall opt *)
+  +> inline opt (* inlining may reveal new tailcall opt *)
   +> deadcode
   +> tailcall
   +> phi
   +> flow
   +> specialize'
   +> eval
-  +> inline
+  +> inline opt
   +> deadcode
   +> print
   +> flow
   +> specialize'
   +> eval
-  +> inline
+  +> inline opt
   +> deadcode
   +> phi
   +> flow
   +> specialize
   +> identity
 
+let o1 = round false
+
 (* o2 *)
 
-let o2 : 'a -> 'a = loop 10 "o1" o1 1 +> print
+let o2 : 'a -> 'a = loop 10 "o1" (round true) 1 +> print
 
 (* o3 *)
 
 let round1 : 'a -> 'a =
   print
   +> tailcall
-  +> inline (* inlining may reveal new tailcall opt *)
+  +> inline false (* inlining may reveal new tailcall opt *)
   +> deadcode (* deadcode required before flow simple -> provided by constant *)
   +> flow_simple (* flow simple to keep information for future tailcall opt *)
   +> specialize'
@@ -452,7 +454,9 @@ let check_js js =
     Javascript.IdentSet.fold
       (fun x acc ->
         match x with
-        | V _ -> assert false
+        | V y ->
+            Format.eprintf "ZZZ %a@." Code.Var.print y;
+            assert false
         | S { name = Utf8 x; _ } -> StringSet.add x acc)
       free
       StringSet.empty