perf(memory): use an arena for RPC decoding

drawback: tracing memory errors with ASAN is less accurate for arena
allocated memory.
Therefore, to start with it is being used for Object types around
serialization/deserialization exclusively. This is going to have
a large impact especially when TUI is refactored as a co-prosess
as all UI events will be serialized and deserialized by nvim itself.

1 files changed, 3 insertions, 2 deletions

diff --git a/src/nvim/eval/funcs.c b/src/nvim/eval/funcs.c
index fc8c9ef445..25f80758d2 100644
--- a/src/nvim/eval/funcs.c
+++ b/src/nvim/eval/funcs.c
@@ -7893,7 +7893,8 @@ static void f_rpcrequest(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   uint64_t chan_id = (uint64_t)argvars[0].vval.v_number;
   const char *method = tv_get_string(&argvars[1]);
 
-  Object result = rpc_send_call(chan_id, method, args, &err);
+  ArenaMem res_mem = NULL;
+  Object result = rpc_send_call(chan_id, method, args, &res_mem, &err);
 
   if (l_provider_call_nesting) {
     current_sctx = save_current_sctx;
@@ -7928,7 +7929,7 @@ static void f_rpcrequest(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   }
 
 end:
-  api_free_object(result);
+  arena_mem_free(res_mem, NULL);
   api_clear_error(&err);
 }