220 32571 <6774d9c5-4f38-474e-a0e9-955d55cd49ab@isocpp.org> article Path: news.gmane.org!.POSTED!not-for-mail From: ma.kalbfuss@web.de Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: relaxing rules for ternary operator. Allow incompatible types. Date: Mon, 22 May 2017 00:03:17 -0700 (PDT) Lines: 846 Approved: news@gmane.org Message-ID: <6774d9c5-4f38-474e-a0e9-955d55cd49ab@isocpp.org> References: <1b5ee8eb-53df-4e98-af2f-829c7bc2e5b2@isocpp.org> <1678895.0nQhqNqFQE@tjmaciei-mobl1> <1620864.HL4j5jKv18@tjmaciei-mobl1> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="----=_Part_872_2104818417.1495436598016" X-Trace: blaine.gmane.org 1495436603 29189 195.159.176.226 (22 May 2017 07:03:23 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Mon, 22 May 2017 07:03:23 +0000 (UTC) To: ISO C++ Standard - Future Proposals Original-X-From: std-proposals+bncBC7YTI72XQOBBNU2RLEQKGQEMONJ6MY@isocpp.org Mon May 22 09:03:18 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qk0-f199.google.com ([209.85.220.199]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dChN4-0007RZ-C8 for gclcip-std-proposals@m.gmane.org; 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contact std-proposals+owners@isocpp.org List-ID: X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:32571 Archived-At: ------=_Part_872_2104818417.1495436598016 Content-Type: multipart/alternative; boundary="----=_Part_873_1716291772.1495436598017" ------=_Part_873_1716291772.1495436598017 Content-Type: text/plain; charset="UTF-8" I've created a new example for looking at the optimizations. struct W{ int doit(){ return 1; } }; struct X{ int doit(){ return 2; } }; struct Y{ int doit(){ return 3; } }; struct Z{ int doit(){ return 4; } }; int example(bool runtime_condition1, bool runtime_condition2) { int result; if(!runtime_condition1) goto ternary_branch_1; if(!runtime_condition2) goto ternary_branch_2; result = W{}.doit() + Y{}.doit(); goto ternary_end; ternary_branch_1: if(!runtime_condition2); goto ternary_branch_3; result = X{}.doit() + Y{}.doit(); goto ternary_end; ternary_branch_2: result = W{}.doit() + Z{}.doit(); goto ternary_end; ternary_branch_3: result = X{}.doit() + Z{}.doit(); ternary_end: return result; } result with -O0 A::doit(): push rbp mov rbp, rsp mov QWORD PTR [rbp-8], rdi nop pop rbp ret B::doit(): push rbp mov rbp, rsp mov QWORD PTR [rbp-8], rdi nop pop rbp ret main: push rbp mov rbp, rsp sub rsp, 16 mov BYTE PTR [rbp-5], 1 mov DWORD PTR [rbp-4], 0 ..L11: cmp DWORD PTR [rbp-4], 99 jg .L4 cmp BYTE PTR [rbp-5], 0 je .L13 nop lea rax, [rbp-6] mov rdi, rax call A::doit() jmp .L9 ..L13: nop lea rax, [rbp-7] mov rdi, rax call B::doit() ..L9: lea rax, [rbp-6] mov rdi, rax call A::doit() nop add DWORD PTR [rbp-4], 1 jmp .L11 ..L4: mov eax, 0 leave ret result with -O1 example(bool, bool): mov eax, 6 test dil, dil je .L1 test sil, sil sete al movzx eax, al add eax, 4 ..L1: rep ret result with -O2 and higher example(bool, bool): test dil, dil mov eax, 6 je .L1 xor eax, eax test sil, sil sete al add eax, 4 ..L1: rep ret Am Montag, 22. Mai 2017 02:12:20 UTC+2 schrieb Thiago Macieira: > > On domingo, 21 de maio de 2017 13:54:51 PDT ma.ka...@web.de > wrote: > > Yeah, i realize that. This is something you have to consider if you're > > using templates extensively. > > No, it isn't. Today, the use of templates does not imply exponential > growth of > generated code. > > That is something completely new with your proposal. > > > This is not the right solution for everything. > > I think in most cases, you use one or at most two ternary operators in > one > > place. For three or more ternary operators the runtime overhead is > > assumably the lesser of two evils. But even if it grows exponentially, > the > > constants are pretty small. Normaly only a few instructions are > involved. > > Not necessarily. Remember that you may not reevaluate the condition, so > either > this generates completely separate code paths (and thus the exponential > expansion) or the result of the evaluation is stored in a hidden variable > that > is evaluated every time you access that automatic variable. > > That is, when you write: > > auto x = runtime_condition1 ? A{} : B{}; > auto y = runtime_conditoin2 ? C{} : D{}; > x.f(); > > This expands to either: > > if (runtime_condition1) { > auto x = A{}; > if (runtime_condition2) { > auto y = C {}; > x.f() + y.f(); > } else { > auto y = D {}; > x.f() + y.f(); > } > } else { > auto x = B{}; > if (runtime_condition2) { > auto y = C {}; > x.f() + y.f(); > } else { > auto y = D {}; > x.f() + y.f(); > } > } > > or to: > > variant x; > variant y; > bool hidden1 = runtime_condition1; > if (hidden1) > x.create(); > else > x.create(); > bool hidden2 = runtime_condition2; > if (hidden2) > y.create(); > else > y.create(); > if (hidden1) { > if (hidden2) > x.as().f() + y.as().f(); > else > x.as().f() + y.as().f(); > } else { > if (hidden2) > x.as().f() + y.as().f(); > else > x.as().f() + y.as().f(); > } > > -- > Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org > Software Architect - Intel Open Source Technology Center > > -- You received this message because you are subscribed to the Google Groups "ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an email to std-proposals+unsubscribe@isocpp.org. To post to this group, send email to std-proposals@isocpp.org. To view this discussion on the web visit https://groups.google.com/a/isocpp.org/d/msgid/std-proposals/6774d9c5-4f38-474e-a0e9-955d55cd49ab%40isocpp.org. ------=_Part_873_1716291772.1495436598017 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
I've created a new example for looking at the optimiza= tions.

struct W{ int doit(){ return 1; } };
struct X{ in= t doit(){ return 2; } <= /span>};
struct Y{ int doit(){ return<= /span> 3; } };
str= uct Z{ int doit(){ return 4; } };


int example(bool runtime_condition1, bool runtime_cond= ition2) {
=C2=A0 =C2=A0 int result;

=C2=A0 =C2=A0 if(!runtime_condition1)
=C2=A0 =C2=A0 =C2=A0 =C2=A0 goto ternary_branch_1;

=C2=A0 =C2=A0 if(!runtime_condition2)
=C2=A0 =C2=A0 =C2=A0 =C2=A0 <= /span>goto= ternary_branch_2= ;

=C2=A0 =C2= =A0 result =3D W{}.doit() + Y{}.doit();
= =C2=A0 =C2=A0 goto t= ernary_end= ;
=C2= =A0 =C2=A0
ternary_branch_1:

=C2=A0 =C2=A0 if(!runtime_condition2);
=C2=A0 =C2=A0 =C2=A0 =C2=A0 goto ternary_branch_3;

=C2=A0 =C2=A0 result =3D X{}.doit() +<= /span> Y{}.doit();
=C2=A0 =C2=A0 goto ternary_end;

ternary_branch_2:

=C2=A0 =C2=A0 result <= span style=3D"color: #660;" class=3D"styled-by-prettify">=3D W{}.doit() + Z{}.doit<= span style=3D"color: #660;" class=3D"styled-by-prettify">();
=C2=A0 =C2=A0 = goto ternary_end;

ternary_branch_3:

=C2=A0 =C2=A0 r= esult =3D<= /span> X{}.doit() + Z{}.doit();<= /span>

ter= nary_end:<= /span>
=C2=A0 = =C2=A0 ret= urn result= ;
}

result with -O0

A::doit()= :
=C2= =A0 =C2=A0 =C2=A0 =C2=A0 push =C2=A0 =C2=A0rbp
=C2=A0 =C2=A0 =C2=A0 =C2= =A0 mov =C2=A0 =C2=A0 rbp, rsp
=C2=A0 =C2=A0 =C2=A0 =C2=A0 mov =C2=A0 =C2=A0 QWORD PTR [rbp-8], rdi
=C2=A0 =C2=A0 =C2=A0 =C2=A0 nop
=C2=A0 =C2=A0 = =C2=A0 =C2=A0 pop =C2=A0 =C2=A0 rbp
=C2=A0 =C2=A0 =C2=A0 =C2=A0 ret
B= ::<= span style=3D"color: #000;" class=3D"styled-by-prettify">doit():
=C2=A0 =C2=A0 =C2=A0 =C2=A0= push =C2=A0 =C2=A0rbp
=C2=A0 =C2=A0 =C2=A0 =C2=A0 mov =C2=A0 =C2=A0 rbp= , rsp
=C2=A0 =C2= =A0 =C2=A0 =C2=A0 mov =C2=A0 =C2=A0 QWORD PTR [rbp-8], rdi=C2=A0 =C2=A0 =C2=A0 =C2=A0 nop
=C2=A0 =C2=A0 =C2=A0 =C2=A0 pop =C2=A0= =C2=A0 rbp
=C2=A0 =C2=A0 =C2=A0 =C2=A0 ret
main:
=C2=A0 =C2=A0 =C2=A0 =C2=A0 push =C2= =A0 =C2=A0rbp
=C2=A0 =C2=A0 =C2=A0 =C2=A0 mov =C2=A0 =C2=A0 rbp, rsp
=C2=A0 =C2=A0 =C2=A0= =C2=A0 su= b =C2=A0 = =C2=A0 rsp= , <= span style=3D"color: #066;" class=3D"styled-by-prettify">16
=C2=A0 =C2=A0 =C2=A0 = =C2=A0 mov =C2=A0 =C2=A0 BYTE PTR [rbp-5= ],<= span style=3D"color: #000;" class=3D"styled-by-prettify"> 1
=C2=A0 =C2=A0 =C2=A0 =C2=A0 mov = =C2=A0 =C2=A0 DWORD PTR [rbp-<= /span>4], 0
.L11:<= br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 cmp =C2=A0 =C2=A0 DWORD PTR [rbp-4], 99=
=C2=A0= =C2=A0 =C2=A0 =C2=A0 jg =C2=A0 =C2=A0 =C2=A0.L4
=C2=A0 =C2=A0 =C2=A0 =C2=A0 cmp =C2=A0 =C2= =A0 BYTE PTR [rbp-5], 0
=C2=A0 =C2=A0 =C2=A0 =C2=A0 je =C2=A0 =C2=A0 =C2=A0.L13
=C2=A0 =C2=A0 = =C2=A0 =C2=A0 nop
=C2=A0 =C2=A0 =C2=A0 =C2=A0 lea =C2=A0 =C2=A0 rax, [rbp-6]<= br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 mov =C2=A0 =C2=A0 rdi, rax
=C2=A0 =C2=A0 =C2=A0 =C2=A0 call = =C2=A0 =C2=A0A::doit= ()<= span style=3D"color: #000;" class=3D"styled-by-prettify">
=C2=A0 =C2=A0 = =C2=A0 =C2=A0 jmp =C2=A0 =C2=A0 .L9
.L13:
=C2=A0 =C2= =A0 =C2=A0 =C2=A0 nop
=C2=A0 =C2=A0 =C2=A0 =C2=A0 lea =C2=A0 =C2=A0 rax<= /span>, [rbp-7]
=C2=A0 =C2=A0 =C2=A0 =C2=A0 mov =C2=A0 =C2=A0 rdi, rax
=C2=A0 =C2=A0 =C2=A0 =C2=A0= call =C2=A0 =C2=A0B::doit()
<= span style=3D"color: #660;" class=3D"styled-by-prettify">.L9:
=C2=A0 =C2=A0 =C2=A0 =C2=A0 lea =C2=A0 = =C2=A0 rax= , <= span style=3D"color: #660;" class=3D"styled-by-prettify">[rbp-6]
=C2=A0 =C2=A0 =C2=A0 =C2=A0 mov =C2=A0 =C2=A0 rdi= , rax
=C2=A0 =C2=A0 =C2= =A0 =C2=A0 call =C2=A0 =C2=A0A::doit()=C2=A0 =C2=A0 =C2=A0 =C2=A0 nop
=C2=A0 =C2=A0 =C2=A0 =C2=A0 add =C2=A0= =C2=A0 DWORD PTR [r= bp-= 4], 1
=C2=A0 =C2=A0 =C2=A0 =C2=A0 jmp =C2=A0 =C2=A0 <= /span>.L11
.L4:
=C2=A0 =C2=A0 =C2=A0 =C2=A0 mov =C2=A0 =C2=A0= eax, 0
=C2=A0 =C2=A0 =C2=A0 =C2=A0 l= eave
=C2=A0 =C2=A0 =C2=A0 =C2=A0 ret

re= sult with -O1

=
example(bool, bool):
=C2=A0 =C2=A0 =C2=A0 =C2=A0 mov = =C2=A0 =C2=A0 eax, <= /span>6
=C2=A0 =C2=A0 = =C2=A0 =C2=A0 test =C2=A0 =C2=A0dil, dil
=C2=A0 =C2=A0 =C2=A0 =C2=A0 je =C2=A0 =C2=A0 =C2=A0= .L1
=C2=A0 =C2=A0= =C2=A0 =C2=A0 test =C2=A0 =C2=A0sil, sil
=C2=A0 =C2=A0 =C2=A0 =C2=A0 sete =C2=A0 =C2=A0al=C2=A0 =C2=A0 =C2=A0 =C2=A0 movzx =C2=A0 eax, al
=C2=A0 =C2=A0 =C2=A0 =C2=A0 add =C2=A0 = =C2=A0 eax= , <= span style=3D"color: #066;" class=3D"styled-by-prettify">4
.L1:
=C2=A0 =C2=A0 =C2=A0 =C2=A0 rep ret

result with -O2 and higher

<= code class=3D"prettyprint">
example(bool, bool= ):
=C2= =A0 =C2=A0 =C2=A0 =C2=A0 test =C2=A0 =C2=A0dil, dil
=C2=A0 =C2=A0 =C2=A0 =C2=A0 mov =C2=A0 = =C2=A0 eax= , <= span style=3D"color: #066;" class=3D"styled-by-prettify">6
=C2=A0 =C2=A0 =C2=A0 = =C2=A0 je =C2=A0 =C2=A0 =C2=A0.L1
=C2=A0 =C2=A0 =C2=A0 =C2=A0 xor =C2=A0 =C2=A0 eax, eax
=C2=A0 =C2=A0 =C2=A0= =C2=A0 test =C2=A0 =C2=A0sil, sil
=C2=A0 =C2=A0 =C2=A0 =C2=A0 sete =C2=A0 =C2=A0al
=C2= =A0 =C2=A0 =C2=A0 =C2=A0 add =C2=A0 =C2=A0 eax, 4
.L1:
=C2=A0 =C2=A0 =C2= =A0 =C2=A0 rep ret



Am Montag, 22. Mai = 2017 02:12:20 UTC+2 schrieb Thiago Macieira:
On domingo, 21 de maio de 2017 13:54:51 PDT ma.ka...@web.de wr= ote:
> Yeah, i realize that. This is something you have to consider if yo= u're
> using templates extensively.=20

No, it isn't. Today, the use of templates does not imply exponentia= l growth of=20
generated code.

That is something completely new with your proposal.

> This is not the right solution for everything.
> I think in most cases, you use one or at most two ternary operator= s in one
> place. For three or more ternary operators the runtime overhead is
> assumably the lesser of two evils. But even if it grows exponentia= lly, the
> constants are pretty small. Normaly only a few instructions are in= volved.

Not necessarily. Remember that you may not reevaluate the condition, so= either=20
this generates completely separate code paths (and thus the exponential= =20
expansion) or the result of the evaluation is stored in a hidden variab= le that=20
is evaluated every time you access that automatic variable.=20

That is, when you write:

=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0auto x =3D runtime_cond= ition1 ? A{} : B{};=20
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0auto y =3D runtime_cond= itoin2 ? C{} : D{};
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0x.f();

This expands to either:

=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0if (runtime_condition1)= {
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0auto x =3D A{};
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0if (runtime_condition2) {
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= auto y =3D C {};
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= x.f() + y.f();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0} else {
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= auto y =3D D {};
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= x.f() + y.f();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0}
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0} else {
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0auto x =3D B{};
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0if (runtime_condition2) {
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= auto y =3D C {};
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= x.f() + y.f();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0} else {
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= auto y =3D D {};
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= x.f() + y.f();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0}
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0}

or to:

=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0variant<A, B> x;
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0variant<C, D> y;
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0bool hidden1 =3D runtim= e_condition1;
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0if (hidden1)
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0x.create<A>();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0else
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0x.create<B>();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0bool hidden2 =3D runtim= e_condition2;
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0if (hidden2)
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0y.create<C>();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0else
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0y.create<D>();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0if (hidden1) {
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0if (hidden2)
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= x.as<A>().f() + y.as= <C>().f();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0else
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= x.as<A>().f() + y.as= <D>().f();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0} else {
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0if (hidden2)
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= x.as<B>().f() + y.as= <C>().f();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0else
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0= x.as<B>().f() + y.as= <D>().f();
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0}

--=20
Thiago Macieira - thiago (AT) macieira.info - thiago (AT) kde.org
=C2=A0 =C2=A0Software Architect - Intel Open Source Technology Center

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------=_Part_873_1716291772.1495436598017-- ------=_Part_872_2104818417.1495436598016-- .