From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ej1-x629.google.com (mail-ej1-x629.google.com [IPv6:2a00:1450:4864:20::629]) by sourceware.org (Postfix) with ESMTPS id 9E4AB385829E; Mon, 19 Sep 2022 07:59:09 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 9E4AB385829E Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-ej1-x629.google.com with SMTP id y3so62630823ejc.1; Mon, 19 Sep 2022 00:59:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date; bh=DXox1/Jy4yfgifiUA2R+1BGm0U4ZLu9fUzhxMyCdTx8=; b=LMJ7cONYj/kil7hL2Vc2ptbCQueNXsg201UDkfIltzCtK63MUW3nsR7f0d5gBn7Dxf y3Y2ac91mmaDtZcD0QjRC/C3J2BCVVAI/DFhIxS29Lv7bqP1K9kLAOd8CuptcUhBb8MU hCRXt7HPEh9as9nXtpr1CPzvDo5VGJMbiiuac4RgKIJRifZfsWnulL0MExvUnUv8NOEz 3H4KnT/8T+JrVyUtokzwPazKBuKGzhY2kc/tHhGBHlbIz3giRydgiKadgWEe85ncnPnX 6wAWFyF2MeXg/Set7rhVPuE2upzolvTvFiF7By5/QilrU6orx+ya6nBZeGx7h5KOqpxX AY6g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date; bh=DXox1/Jy4yfgifiUA2R+1BGm0U4ZLu9fUzhxMyCdTx8=; b=FZlr19X8IW6SrsI9OYSUvCSHhwQUj+WICjtEyjV4lWgjD5LGUC9NH3DGs0y0u0PNXT SFwyRkbvhmSj8gyF4w/uy98MqzJbjyQdx2RT+OH5XPDlo2WS9g5VPEQnvWIxMfGGFH8r PCbMiRcP3wAmhW5thOBPA/Bgr+NXvA9mufEnVlXuAoaTKEWEyUI3d2fMf+yCDzUS0+XZ K/oPvSkSmGleFQrDlRi4fbR+1XmnHY1cxaondm1BK98s9gxjRXtQcHJzeEElCT9Vst/L IzpV+91OPWo9pWOJuk6/ZN1d8wVRWG/pVgGUZnyTwfcNk24+aO3tfzB7PnI7WX2onqb+ OgBA== X-Gm-Message-State: ACrzQf2uD/tRsv+yI+gSMDkvypbXnfDFV24zJ8u/CQDY/NIcwUflG9f2 yOxHQMrEo6jOlAucKMNCWjEWK0KH14wJJxq0FVM= X-Google-Smtp-Source: AMsMyM6GbAS8zzceIafUpXNPI6XfMv0ByMq2TkChX0yQmlgy2F+vn/Au4Kv66Kb3ep1GvkseXb+yb2WhvzlJhCZeNoI= X-Received: by 2002:a17:906:8251:b0:781:8016:2dc9 with SMTP id f17-20020a170906825100b0078180162dc9mr477683ejx.488.1663574348445; Mon, 19 Sep 2022 00:59:08 -0700 (PDT) MIME-Version: 1.0 References: <62e5ef00-b739-37b2-269d-67b9089dfc94@orange.fr> In-Reply-To: <62e5ef00-b739-37b2-269d-67b9089dfc94@orange.fr> From: Richard Biener Date: Mon, 19 Sep 2022 09:58:56 +0200 Message-ID: Subject: Re: [PATCH 09/10] fortran: Support clobbering of variable subreferences [PR88364] To: Mikael Morin Cc: Thomas Koenig , Mikael Morin , gcc-patches@gcc.gnu.org, fortran@gcc.gnu.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-8.1 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,GIT_PATCH_0,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Mon, Sep 19, 2022 at 9:31 AM Mikael Morin wrote= : > > Le 18/09/2022 =C3=A0 12:48, Richard Biener a =C3=A9crit : > > > >> Does *(&a[1]) count as a pointer dereference? > > > > Yes, technically. > > > >> Even in the original dump it is already simplified to a straight a[1= ]. > > > > But this not anymore. The check can probably be relaxed, it stems from= the dual purpose of CLOBBER. > > > So the following makes the frontend-emitted IL valid, by handing the > simplification over to the middle-end, but I can't help thinking that > behavior won't be more reliable. I think that will just delay the folding. We are basically relying on the frontends to restrict what they produce, the *ptr case was specifically for C++ this in CTOR/DTORs and during inlining we throw away all clobbers that end up "wrong" but I guess we might have latent issues when we obfuscate the address in the caller enough= and get undesired simplification ... > > diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc > index f8fcd2d97d9..5fb9a3a536d 100644 > --- a/gcc/fortran/trans-expr.cc > +++ b/gcc/fortran/trans-expr.cc > @@ -6544,8 +6544,9 @@ gfc_conv_procedure_call (gfc_se * se, gfc_symbol * > sym, > && !sym->attr.elemental) > { > tree var; > - var =3D build_fold_indirect_ref_loc (input_loca= tion, > - parmse.expr)= ; > + var =3D build1_loc (input_location, INDIRECT_RE= F, > + TREE_TYPE (TREE_TYPE > (parmse.expr)), > + parmse.expr); > tree clobber =3D build_clobber (TREE_TYPE (var= )); > gfc_add_modify (&clobbers, var, clobber); > } >