diff options
| -rw-r--r-- | lib/hipe/icode/hipe_beam_to_icode.erl | 31 |
1 files changed, 20 insertions, 11 deletions
diff --git a/lib/hipe/icode/hipe_beam_to_icode.erl b/lib/hipe/icode/hipe_beam_to_icode.erl index 100bc0b0e2..610578dfbc 100644 --- a/lib/hipe/icode/hipe_beam_to_icode.erl +++ b/lib/hipe/icode/hipe_beam_to_icode.erl @@ -148,7 +148,8 @@ trans_mfa_code(M,F,A, FunBeamCode, ClosureInfo) -> {Code3,_Env3} = mk_debug_calltrace(MFA, Env1, Code2), {Code3,_Env3} = {Code2,Env1}), %% For stack optimization - Leafness = leafness(Code3), + IsClosure = get_closure_info(MFA, ClosureInfo) =/= not_a_closure, + Leafness = leafness(Code3, IsClosure), IsLeaf = is_leaf_code(Leafness), Code4 = [FunLbl | @@ -156,7 +157,6 @@ trans_mfa_code(M,F,A, FunBeamCode, ClosureInfo) -> false -> Code3; true -> [mk_redtest()|Code3] end], - IsClosure = get_closure_info(MFA, ClosureInfo) =/= not_a_closure, Code5 = hipe_icode:mk_icode(MFA, FunArgs, IsClosure, IsLeaf, remove_dead_code(Code4), hipe_gensym:var_range(icode), @@ -173,12 +173,12 @@ trans_mfa_code(M,F,A, FunBeamCode, ClosureInfo) -> mk_redtest() -> hipe_icode:mk_primop([], redtest, []). -leafness(Is) -> % -> true, selfrec, or false - leafness(Is, true). +leafness(Is, IsClosure) -> % -> true, selfrec, closure, or false + leafness(Is, IsClosure, true). -leafness([], Leafness) -> +leafness([], _IsClosure, Leafness) -> Leafness; -leafness([I|Is], Leafness) -> +leafness([I|Is], IsClosure, Leafness) -> case I of #icode_comment{} -> %% BEAM self-tailcalls become gotos, but they leave @@ -191,7 +191,7 @@ leafness([I|Is], Leafness) -> 'self_tail_recursive' -> selfrec; % call_only to selfrec _ -> Leafness end, - leafness(Is, NewLeafness); + leafness(Is, IsClosure, NewLeafness); #icode_call{} -> case hipe_icode:call_type(I) of 'primop' -> @@ -199,12 +199,12 @@ leafness([I|Is], Leafness) -> call_fun -> false; % Calls closure enter_fun -> false; % Calls closure #apply_N{} -> false; - _ -> leafness(Is, Leafness) % Other primop calls are ok + _ -> leafness(Is, IsClosure, Leafness) % Other primop calls are ok end; T when T =:= 'local' orelse T =:= 'remote' -> {M,F,A} = hipe_icode:call_fun(I), case erlang:is_builtin(M, F, A) of - true -> leafness(Is, Leafness); + true -> leafness(Is, IsClosure, Leafness); false -> false end end; @@ -223,11 +223,12 @@ leafness([I|Is], Leafness) -> T when T =:= 'local' orelse T =:= 'remote' -> {M,F,A} = hipe_icode:enter_fun(I), case erlang:is_builtin(M, F, A) of - true -> leafness(Is, Leafness); + true -> leafness(Is, IsClosure, Leafness); + _ when IsClosure -> leafness(Is, IsClosure, closure); _ -> false end end; - _ -> leafness(Is, Leafness) + _ -> leafness(Is, IsClosure, Leafness) end. %% XXX: this old stuff is passed around but essentially unused @@ -235,12 +236,20 @@ is_leaf_code(Leafness) -> case Leafness of true -> true; selfrec -> true; + closure -> false; false -> false end. needs_redtest(Leafness) -> case Leafness of true -> false; + %% A "leaf" closure may contain tailcalls to non-closures in addition to + %% what other leaves may contain. Omitting the redtest is useful to generate + %% shorter code for closures generated by (fun F/A), and is safe since + %% control flow cannot return to a "leaf" closure again without a reduction + %% being consumed. This is true since no function that can call a closure + %% will ever have its redtest omitted. + closure -> false; selfrec -> true; false -> true end. |