From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTPS id DD1243858D39 for ; Sat, 6 Aug 2022 22:41:34 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org DD1243858D39 Received: from mail-qv1-f72.google.com (mail-qv1-f72.google.com [209.85.219.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-630-Cy77JXChPgy3Naia3MqFjA-1; Sat, 06 Aug 2022 18:41:23 -0400 X-MC-Unique: Cy77JXChPgy3Naia3MqFjA-1 Received: by mail-qv1-f72.google.com with SMTP id a11-20020ad45c4b000000b004747a998b9eso3096624qva.9 for ; Sat, 06 Aug 2022 15:41:23 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=apeR0OW5Fr3CDKuKRImTkOWoJ5fhqGJGEnqcK//JCRc=; b=Hzub2za9iVDBMzOXMiwJAFqxI993W68LxkpACs75MA1cXGnPqINvKHDp1bxXg5rtHa 94Evup7xNxikO6aBW/3l/DH5buzSl0u2OZ8uNghLlSfiJSEMOF3OOLl2TfV2MRC87z9/ KDoieDstwLqyGY49AAFZxYN6+ozNF0W/nyViTljQWk4YHt2hHagZuhqWNWpILt0AH8k6 55V4uh5U9/V10uuJDJ2zocryPJLXlH63t2GRf2dYvm0MyHooWh0UCHQ/Y0JovvgJzfbX XmSesomQp22wjPwUk+2TMug0kFyX4pBo3bHgmPW98BxrYclcsTN5i3wGKM/Uyjb46Uwi Q1Ow== X-Gm-Message-State: ACgBeo12WtXR1/ibm/IKhkrasEXgm2Ya1eCpjnqXmVtQ5s4WcLhqHgQN zW0VnbhHAYANF3SMUJmoYGF08121KyyjZdcDG07LGUlcPQfkq/4e6AfM8dR2TFEl6cdfP7kZa6+ lcTLk6YbabCXEwCyssw== X-Received: by 2002:ac8:58d1:0:b0:31f:70c:aee7 with SMTP id u17-20020ac858d1000000b0031f070caee7mr11086667qta.367.1659825683261; Sat, 06 Aug 2022 15:41:23 -0700 (PDT) X-Google-Smtp-Source: AA6agR4zG3tSZN6LjvvzS3TUS/sDy6vBvJjDfHW9I4+9f8FdNF0td8G6x5Ems2qvMkaHEK6WILvN4A== X-Received: by 2002:ac8:58d1:0:b0:31f:70c:aee7 with SMTP id u17-20020ac858d1000000b0031f070caee7mr11086657qta.367.1659825682949; Sat, 06 Aug 2022 15:41:22 -0700 (PDT) Received: from [192.168.44.44] ([72.2.237.35]) by smtp.gmail.com with ESMTPSA id m20-20020a05620a24d400b006a787380a5csm6438567qkn.67.2022.08.06.15.41.19 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 06 Aug 2022 15:41:22 -0700 (PDT) Message-ID: <083bf8c7-068f-8f9c-e864-80be71e66cce@redhat.com> Date: Sat, 6 Aug 2022 15:41:14 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.12.0 Subject: Re: [PATCH] c++, v4: Add support for __real__/__imag__ modifications in constant expressions [PR88174] To: Jakub Jelinek Cc: gcc-patches@gcc.gnu.org References: <4d9319d5-1890-7c99-6c1b-d940f873a590@redhat.com> <38ccc92a-6772-75d9-1ac9-fc3252734291@redhat.com> From: Jason Merrill In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-5.8 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, NICE_REPLY_A, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_NONE, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 06 Aug 2022 22:41:45 -0000 On 7/27/22 02:09, Jakub Jelinek wrote: > On Tue, Jul 05, 2022 at 04:44:41PM -0400, Jason Merrill wrote: >> But preeval should always be true, so we'd never reach the new handling in >> the if (!preeval) block. Certainly the new testcase doesn't exercise this >> code. > > Ok, changed now. > > I had to keep the ctors[i] = valp; statement in the !preeval block, because > otherwise e.g. 20_util/optional/monadic/transform.cc test fails randomly. > It was wrong already before the patch, it would adjust > TREE_CONSTANT/TREE_SIDE_EFFECTS sometimes on no longer used trees, > but with the vector holding pointers to trees rather than trees it is even > more severe. > > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? OK, thanks. > 2022-07-27 Jakub Jelinek > > PR c++/88174 > * constexpr.cc (cxx_eval_store_expression): Handle REALPART_EXPR > and IMAGPART_EXPR. Change ctors from releasing_vec to > auto_vec, adjust all uses. For !preeval, update ctors > vector. > > * g++.dg/cpp1y/constexpr-complex1.C: New test. > > --- gcc/cp/constexpr.cc.jj 2022-07-04 12:26:18.147053851 +0200 > +++ gcc/cp/constexpr.cc 2022-07-26 17:35:53.100556949 +0200 > @@ -5726,6 +5726,20 @@ cxx_eval_store_expression (const constex > } > break; > > + case REALPART_EXPR: > + gcc_assert (probe == target); > + vec_safe_push (refs, probe); > + vec_safe_push (refs, TREE_TYPE (probe)); > + probe = TREE_OPERAND (probe, 0); > + break; > + > + case IMAGPART_EXPR: > + gcc_assert (probe == target); > + vec_safe_push (refs, probe); > + vec_safe_push (refs, TREE_TYPE (probe)); > + probe = TREE_OPERAND (probe, 0); > + break; > + > default: > if (evaluated) > object = probe; > @@ -5764,7 +5778,8 @@ cxx_eval_store_expression (const constex > type = TREE_TYPE (object); > bool no_zero_init = true; > > - releasing_vec ctors, indexes; > + auto_vec ctors; > + releasing_vec indexes; > auto_vec index_pos_hints; > bool activated_union_member_p = false; > bool empty_base = false; > @@ -5804,14 +5819,36 @@ cxx_eval_store_expression (const constex > *valp = ary_ctor; > } > > - /* If the value of object is already zero-initialized, any new ctors for > - subobjects will also be zero-initialized. */ > - no_zero_init = CONSTRUCTOR_NO_CLEARING (*valp); > - > enum tree_code code = TREE_CODE (type); > tree reftype = refs->pop(); > tree index = refs->pop(); > > + if (code == COMPLEX_TYPE) > + { > + if (TREE_CODE (*valp) == COMPLEX_CST) > + *valp = build2 (COMPLEX_EXPR, type, TREE_REALPART (*valp), > + TREE_IMAGPART (*valp)); > + else if (TREE_CODE (*valp) == CONSTRUCTOR > + && CONSTRUCTOR_NELTS (*valp) == 0 > + && CONSTRUCTOR_NO_CLEARING (*valp)) > + { > + tree r = build_constructor (reftype, NULL); > + CONSTRUCTOR_NO_CLEARING (r) = 1; > + *valp = build2 (COMPLEX_EXPR, type, r, r); > + } > + gcc_assert (TREE_CODE (*valp) == COMPLEX_EXPR); > + ctors.safe_push (valp); > + vec_safe_push (indexes, index); > + valp = &TREE_OPERAND (*valp, TREE_CODE (index) == IMAGPART_EXPR); > + gcc_checking_assert (refs->is_empty ()); > + type = reftype; > + break; > + } > + > + /* If the value of object is already zero-initialized, any new ctors for > + subobjects will also be zero-initialized. */ > + no_zero_init = CONSTRUCTOR_NO_CLEARING (*valp); > + > if (code == RECORD_TYPE && is_empty_field (index)) > /* Don't build a sub-CONSTRUCTOR for an empty base or field, as they > have no data and might have an offset lower than previously declared > @@ -5854,7 +5891,7 @@ cxx_eval_store_expression (const constex > no_zero_init = true; > } > > - vec_safe_push (ctors, *valp); > + ctors.safe_push (valp); > vec_safe_push (indexes, index); > > constructor_elt *cep > @@ -5916,11 +5953,11 @@ cxx_eval_store_expression (const constex > semantics are not applied on an object under construction. > They come into effect when the constructor for the most > derived object ends." */ > - for (tree elt : *ctors) > + for (tree *elt : ctors) > if (same_type_ignoring_top_level_qualifiers_p > - (TREE_TYPE (const_object_being_modified), TREE_TYPE (elt))) > + (TREE_TYPE (const_object_being_modified), TREE_TYPE (*elt))) > { > - fail = TREE_READONLY (elt); > + fail = TREE_READONLY (*elt); > break; > } > } > @@ -5961,6 +5998,7 @@ cxx_eval_store_expression (const constex > valp = ctx->global->values.get (object); > for (unsigned i = 0; i < vec_safe_length (indexes); i++) > { > + ctors[i] = valp; > constructor_elt *cep > = get_or_insert_ctor_field (*valp, indexes[i], index_pos_hints[i]); > valp = &cep->value; > @@ -6023,17 +6061,45 @@ cxx_eval_store_expression (const constex > CONSTRUCTORs, if any. */ > bool c = TREE_CONSTANT (init); > bool s = TREE_SIDE_EFFECTS (init); > + if (!indexes->is_empty ()) > + { > + tree last = indexes->last (); > + if (TREE_CODE (last) == REALPART_EXPR > + || TREE_CODE (last) == IMAGPART_EXPR) > + { > + /* And canonicalize COMPLEX_EXPR into COMPLEX_CST if > + possible. */ > + tree *cexpr = ctors.last (); > + if (tree c = const_binop (COMPLEX_EXPR, TREE_TYPE (*cexpr), > + TREE_OPERAND (*cexpr, 0), > + TREE_OPERAND (*cexpr, 1))) > + *cexpr = c; > + else > + { > + TREE_CONSTANT (*cexpr) > + = (TREE_CONSTANT (TREE_OPERAND (*cexpr, 0)) > + & TREE_CONSTANT (TREE_OPERAND (*cexpr, 1))); > + TREE_SIDE_EFFECTS (*cexpr) > + = (TREE_SIDE_EFFECTS (TREE_OPERAND (*cexpr, 0)) > + | TREE_SIDE_EFFECTS (TREE_OPERAND (*cexpr, 1))); > + } > + c = TREE_CONSTANT (*cexpr); > + s = TREE_SIDE_EFFECTS (*cexpr); > + } > + } > if (!c || s || activated_union_member_p) > - for (tree elt : *ctors) > + for (tree *elt : ctors) > { > + if (TREE_CODE (*elt) != CONSTRUCTOR) > + continue; > if (!c) > - TREE_CONSTANT (elt) = false; > + TREE_CONSTANT (*elt) = false; > if (s) > - TREE_SIDE_EFFECTS (elt) = true; > + TREE_SIDE_EFFECTS (*elt) = true; > /* Clear CONSTRUCTOR_NO_CLEARING since we've activated a member of > this union. */ > - if (TREE_CODE (TREE_TYPE (elt)) == UNION_TYPE) > - CONSTRUCTOR_NO_CLEARING (elt) = false; > + if (TREE_CODE (TREE_TYPE (*elt)) == UNION_TYPE) > + CONSTRUCTOR_NO_CLEARING (*elt) = false; > } > > if (lval) > --- gcc/testsuite/g++.dg/cpp1y/constexpr-complex1.C.jj 2022-07-04 17:30:47.884580998 +0200 > +++ gcc/testsuite/g++.dg/cpp1y/constexpr-complex1.C 2022-07-04 17:30:47.884580998 +0200 > @@ -0,0 +1,24 @@ > +// PR c++/88174 > +// { dg-do compile { target c++14 } } > + > +constexpr bool > +foo (double x, double y, double z, double w) > +{ > + __complex__ double a = 0; > + __real__ a = x; > + __imag__ a = y; > +#if __cpp_constexpr >= 201907L > + __complex__ double b; > + __real__ b = z; > +#else > + __complex__ double b = z; > +#endif > + __imag__ b = w; > + a += b; > + a -= b; > + a *= b; > + a /= b; > + return __real__ a == x && __imag__ a == y; > +} > + > +static_assert (foo (1.0, 2.0, 3.0, 4.0), ""); > > > Jakub >