Merge pull request #1903 from pguyot/w42/armv6m-use-literal-pool-to-reduce-binary-size

JIT (armv6m): use literal pool to reduce binary size

Continuation of:
- #1901

These changes are made under both the "Apache 2.0" and the "GNU Lesser General
Public License 2.1 or later" license terms (dual license).

SPDX-License-Identifier: Apache-2.0 OR LGPL-2.1-or-later

Author: bettio

libs/estdlib/src/code_server.erl

@@ -164,8 +164,8 @@ load(Module) ->
                             code_server:literal_resolver(Module, Index)
                         end,
                         TypeResolver = fun(Index) -> code_server:type_resolver(Module, Index) end,
-                        Stream0 = jit:stream(jit_mmap_size(byte_size(Code))),
-                        {BackendModule, BackendState0} = jit:backend(Stream0),
+                        {StreamModule, Stream0} = jit:stream(jit_mmap_size(byte_size(Code))),
+                        {BackendModule, BackendState0} = jit:backend(StreamModule, Stream0),
                         {LabelsCount, BackendState1} = jit:compile(
                             Code,
                             AtomResolver,
@@ -175,7 +175,8 @@ load(Module) ->
                             BackendState0
                         ),
                         Stream1 = BackendModule:stream(BackendState1),
-                        code_server:set_native_code(Module, LabelsCount, Stream1),
+                        Stream2 = StreamModule:flush(Stream1),
+                        code_server:set_native_code(Module, LabelsCount, Stream2),
                         End = erlang:system_time(millisecond),
                         io:format("~B ms (bytecode: ~B bytes, native code: ~B bytes)\n", [
                             End - Start, byte_size(Code), BackendModule:offset(BackendState1)

libs/jit/src/jit.erl

@@ -22,7 +22,7 @@
 
 -export([
     stream/1,
-    backend/1,
+    backend/2,
     beam_chunk_header/3,
     compile/6
 ]).
@@ -148,7 +148,8 @@ compile(
     },
     {State1, MSt2} = first_pass(Opcodes, MMod, MSt1, State0),
     MSt3 = second_pass(MMod, MSt2, State1),
-    {LabelsCount, MSt3};
+    MSt4 = MMod:flush(MSt3),
+    {LabelsCount, MSt4};
 compile(
     <<16:32, 0:32, OpcodeMax:32, _LabelsCount:32, _FunctionsCount:32, _Opcodes/binary>>,
     _AtomResolver,
@@ -3852,7 +3853,7 @@ variant() ->
 
 %% @doc Instantiate backend for this platform
 %% @return A tuple with the backend module and the backend state for this platform
-backend({StreamModule, Stream}) ->
+backend(StreamModule, Stream) ->
     BackendModule = ?MODULE:backend_module(),
     Variant = ?MODULE:variant(),
     BackendState = BackendModule:new(Variant, StreamModule, Stream),

libs/jit/src/jit_aarch64.erl

@@ -25,6 +25,7 @@
     new/3,
     stream/1,
     offset/1,
+    flush/1,
     debugger/1,
     used_regs/1,
     available_regs/1,
@@ -259,6 +260,16 @@ stream(#state{stream = Stream}) ->
 offset(#state{stream_module = StreamModule, stream = Stream}) ->
     StreamModule:offset(Stream).
 
+%%-----------------------------------------------------------------------------
+%% @doc Flush the current state (unused on aarch64)
+%% @end
+%% @param State current backend state
+%% @return The flushed state
+%%-----------------------------------------------------------------------------
+-spec flush(state()) -> state().
+flush(#state{} = State) ->
+    State.
+
 %%-----------------------------------------------------------------------------
 %% @doc Emit a debugger of breakpoint instruction. This is used for debugging
 %% and not in production.