From 44e3810be19f58f0348cd2c38de9bb1b2e9d4c6e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Micha=C5=82=20Muska=C5=82a?= Date: Sun, 5 Aug 2018 00:15:33 +0200 Subject: Rewrite erlang:get_stacktrace calls to primop when safe This allows taking advantage of further optimisations, like the raw_raise instruction for code that can't upgrade (yet) to the new stacktrace syntax for compatibility reasons. The rewrite is only done when it is safe - when the get_stacktrace call is the very first thing the handler does. --- lib/compiler/src/sys_core_fold.erl | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/compiler/src/sys_core_fold.erl b/lib/compiler/src/sys_core_fold.erl index 0aa58a46e4..f5f652a954 100644 --- a/lib/compiler/src/sys_core_fold.erl +++ b/lib/compiler/src/sys_core_fold.erl @@ -480,9 +480,21 @@ expr(#c_try{anno=A,arg=E0,vars=Vs0,body=B0,evars=Evs0,handler=H0}=Try, _, Sub0) false -> {Evs1,Sub2} = var_list(Evs0, Sub0), H1 = body(H0, value, Sub2), - Try#c_try{arg=E1,vars=Vs1,body=B1,evars=Evs1,handler=H1} + H2 = opt_try_handler(H1, lists:last(Evs1)), + Try#c_try{arg=E1,vars=Vs1,body=B1,evars=Evs1,handler=H2} end. +%% Attempts to convert old erlang:get_stacktrace/0 calls into the new +%% three-argument catch, with possibility of further optimisations. +opt_try_handler(#c_call{anno=A,module=#c_literal{val=erlang},name=#c_literal{val=get_stacktrace},args=[]}, Var) -> + #c_primop{anno=A,name=#c_literal{val=build_stacktrace},args=[Var]}; +opt_try_handler(#c_case{clauses=Cs0} = Case, Var) -> + Cs = [C#c_clause{body=opt_try_handler(B, Var)} || #c_clause{body=B} = C <- Cs0], + Case#c_case{clauses=Cs}; +opt_try_handler(#c_let{arg=Arg} = Let, Var) -> + Let#c_let{arg=opt_try_handler(Arg, Var)}; +opt_try_handler(X, _) -> X. + expr_list(Es, Ctxt, Sub) -> [expr(E, Ctxt, Sub) || E <- Es]. -- cgit v1.2.3