Infer at once

Author: josevalim

Makefile

@@ -107,6 +107,7 @@ $(KERNEL): lib/elixir/src/* lib/elixir/lib/*.ex lib/elixir/lib/*/*.ex lib/elixir
 	fi
 	@ echo "==> elixir (compile)";
 	$(Q) cd lib/elixir && ../../$(ELIXIRC_MIN_SIG) "lib/**/*.ex" -o ebin;
+	$(Q) bin/elixir lib/elixir/scripts/infer.exs;
 
 $(APP): lib/elixir/src/elixir.app.src lib/elixir/ebin VERSION $(GENERATE_APP)
 	$(Q) $(GENERATE_APP) $(VERSION)

lib/elixir/scripts/infer.exs

@@ -0,0 +1,64 @@
+parent = self()
+{:ok, checker} = Module.ParallelChecker.start_link()
+
+{time, modules} =
+  :timer.tc(fn ->
+    [_ | _] = paths = Path.wildcard(Path.join(__DIR__, "../ebin/Elixir.*.beam"))
+
+    paths
+    |> Task.async_stream(
+      fn path ->
+        path = Path.expand(path)
+        Module.ParallelChecker.put(parent, checker)
+        cache = Module.ParallelChecker.get()
+        binary = File.read!(path)
+
+        {:ok, {_, [{:debug_info, debug_info}, {_, checker_blob}]}} =
+          :beam_lib.chunks(binary, [:debug_info, ~c"ExCk"])
+
+        {:debug_info_v1, _backend, {:elixir_v1, module_map, _specs}} = debug_info
+
+        %{module: module, file: file, attributes: attributes, definitions: definitions} =
+          module_map
+
+        {_, checker} = :erlang.binary_to_term(checker_blob)
+        env = :elixir_env.new()
+
+        # We assume that all private functions have been invoked at this point
+        private =
+          for {fun_arity, kind, _, _} <- definitions, kind in [:defp, :defmacrop], do: fun_arity
+
+        {signatures, _} =
+          Module.Types.infer(module, file, attributes, definitions, private, env, cache)
+
+        checker =
+          update_in(checker.exports, fn exports ->
+            for {fun, info} <- exports do
+              {fun, %{info | sig: Map.get(signatures, fun, info.sig)}}
+            end
+          end)
+
+        [{"ExCk", checker_chunk}] = :elixir_erl.checker_chunk(checker, [])
+        {:ok, ^module, chunks} = :beam_lib.all_chunks(binary)
+
+        {:ok, new_binary} =
+          chunks
+          |> List.keyreplace(~c"ExCk", 0, {~c"ExCk", checker_chunk})
+          |> :beam_lib.build_module()
+
+        File.write!(path, new_binary)
+        {module, path}
+      end,
+      timeout: :infinity
+    )
+    |> Enum.map(fn {:ok, result} -> result end)
+  end)
+
+IO.puts(:stderr, ["Type inferred stdlib in ", Integer.to_string(div(time, 1000)), "ms"])
+
+{time, _} =
+  :timer.tc(fn ->
+    Module.ParallelChecker.verify(checker, modules)
+  end)
+
+IO.puts(:stderr, ["Type checked stdlib in ", Integer.to_string(div(time, 1000)), "ms"])