diff options
Diffstat (limited to 'lib/compiler/src')
| -rw-r--r-- | lib/compiler/src/beam_bsm.erl | 1 | ||||
| -rw-r--r-- | lib/compiler/src/beam_validator.erl | 1 | ||||
| -rw-r--r-- | lib/compiler/src/sys_core_fold.erl | 29 | ||||
| -rw-r--r-- | lib/compiler/src/v3_core.erl | 3 |
4 files changed, 31 insertions, 3 deletions
diff --git a/lib/compiler/src/beam_bsm.erl b/lib/compiler/src/beam_bsm.erl index fdfcb08125..d54c2a9fde 100644 --- a/lib/compiler/src/beam_bsm.erl +++ b/lib/compiler/src/beam_bsm.erl @@ -209,6 +209,7 @@ btb_reaches_match_2([{call,Arity,{f,Lbl}}|Is], Regs, D) -> btb_reaches_match_2([{apply,Arity}|Is], Regs, D) -> btb_call(Arity+2, apply, Regs, Is, D); btb_reaches_match_2([{call_fun,Live}=I|Is], Regs, D) -> + btb_ensure_not_used([{x,Live}], I, Regs), btb_call(Live, I, Regs, Is, D); btb_reaches_match_2([{make_fun2,_,_,_,Live}|Is], Regs, D) -> btb_call(Live, make_fun2, Regs, Is, D); diff --git a/lib/compiler/src/beam_validator.erl b/lib/compiler/src/beam_validator.erl index 97f84da08f..682f7adbc2 100644 --- a/lib/compiler/src/beam_validator.erl +++ b/lib/compiler/src/beam_validator.erl @@ -574,6 +574,7 @@ valfun_4({apply,Live}, Vst) -> valfun_4({apply_last,Live,_}, Vst) -> tail_call(apply, Live+2, Vst); valfun_4({call_fun,Live}, Vst) -> + validate_src([{x,Live}], Vst), call('fun', Live+1, Vst); valfun_4({call,Live,Func}, Vst) -> call(Func, Live, Vst); diff --git a/lib/compiler/src/sys_core_fold.erl b/lib/compiler/src/sys_core_fold.erl index d1eec9e347..e302e2324d 100644 --- a/lib/compiler/src/sys_core_fold.erl +++ b/lib/compiler/src/sys_core_fold.erl @@ -305,6 +305,10 @@ expr(#c_let{}=Let, Ctxt, Sub) -> %% Now recursively re-process the new expression. expr(Expr, Ctxt, sub_new_preserve_types(Sub)) end; +expr(#c_letrec{body=#c_var{}}=Letrec, effect, _Sub) -> + %% This is named fun in an 'effect' context. Warn and ignore. + add_warning(Letrec, useless_building), + void(); expr(#c_letrec{defs=Fs0,body=B0}=Letrec, Ctxt, Sub) -> Fs1 = map(fun ({Name,Fb}) -> {Name,expr(Fb, {letrec,Ctxt}, Sub)} @@ -1941,9 +1945,30 @@ eval_case(#c_case{arg=E,clauses=[#c_clause{pats=Ps0,body=B}]}, Sub) -> true -> cerl:values_es(E); false -> [E] end, - {true,Bs} = cerl_clauses:match_list(Ps0, Es), + %% Consider: + %% + %% case SomeSideEffect() of + %% X=Y -> ... + %% end + %% + %% We must not rewrite it to: + %% + %% let <X,Y> = <SomeSideEffect(),SomeSideEffect()> in ... + %% + %% because SomeSideEffect() would be called evaluated twice. + %% + %% Instead we must evaluate the case expression in an outer let + %% like this: + %% + %% let NewVar = SomeSideEffect() in + %% let <X,Y> = <NewVar,NewVar> in ... + %% + Vs = make_vars([], length(Es)), + {true,Bs} = cerl_clauses:match_list(Ps0, Vs), {Ps,As} = unzip(Bs), - expr(#c_let{vars=Ps,arg=core_lib:make_values(As),body=B}, sub_new(Sub)); + InnerLet = cerl:c_let(Ps, core_lib:make_values(As), B), + Let = cerl:c_let(Vs, E, InnerLet), + expr(Let, sub_new(Sub)); eval_case(Case, _) -> Case. %% case_opt(CaseArg, [Clause]) -> {CaseArg,[Clause]}. diff --git a/lib/compiler/src/v3_core.erl b/lib/compiler/src/v3_core.erl index e30bfa729c..59863f52ec 100644 --- a/lib/compiler/src/v3_core.erl +++ b/lib/compiler/src/v3_core.erl @@ -2088,7 +2088,8 @@ cexpr(#ifun{anno=#a{us=Us0}=A0,name={named,Name},fc=#iclause{pats=Ps}}=Fun0, RecVar = #c_var{name={Name,length(Ps)}}, Let = #c_let{vars=[#c_var{name=Name}],arg=RecVar,body=Body}, CFun1 = CFun0#c_fun{body=Let}, - Letrec = #c_letrec{defs=[{RecVar,CFun1}], + Letrec = #c_letrec{anno=A0#a.anno, + defs=[{RecVar,CFun1}], body=RecVar}, {Letrec,[],Us1,St1} end; |