From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by sourceware.org (Postfix) with ESMTPS id 4CFC63858D1E; Fri, 9 Jun 2023 08:51:05 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 4CFC63858D1E Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=suse.de Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out2.suse.de (Postfix) with ESMTP id 76B2B1FDF3; Fri, 9 Jun 2023 08:51:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1686300664; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=wwR+2FploehoyYTNhGsWGhcvH7a6Rxl7Z3zff9QK20M=; b=t8Vj6LBdJvigLrdiMwVyvs/KyWD+SkzoBbLRwXRtQZ15SXhBL64uW21mzF1gatnPZM39Sy 1v95sJ+PU0hHSlraVPssjxff4Tmfbs5/++i+koufUEndgX1tB6yhFal0WW9jvzL4Pb8Adg FKRo/KJhBMqTHlotF2wZQw6G6XpX8yk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1686300664; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=wwR+2FploehoyYTNhGsWGhcvH7a6Rxl7Z3zff9QK20M=; b=0irC0Pb539GWSeHXhomzOta3HDSVZfOsDkAWL1hnxFLmvI9JSQV/1aGYlOk0REJI+jfqh9 YlSRnfo26VuERbAw== Received: from wotan.suse.de (wotan.suse.de [10.160.0.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by relay2.suse.de (Postfix) with ESMTPS id 5A27D2C141; Fri, 9 Jun 2023 08:51:04 +0000 (UTC) Date: Fri, 9 Jun 2023 08:51:04 +0000 (UTC) From: Richard Biener To: Richard Sandiford cc: guojiufu , gcc-patches@gcc.gnu.org, jeffreyalaw@gmail.com, segher@kernel.crashing.org, dje.gcc@gmail.com, linkw@gcc.gnu.org, bergner@linux.ibm.com Subject: Re: [PATCH] Make sure SCALAR_INT_MODE_P before invoke try_const_anchors In-Reply-To: Message-ID: References: <20230609052847.2128612-1-guojiufu@linux.ibm.com> <56dbba43adda001d1668c29e8024c85d@linux.ibm.com> User-Agent: Alpine 2.22 (LSU 394 2020-01-19) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Spam-Status: No, score=-4.9 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,KAM_SHORT,SPF_HELO_NONE,SPF_PASS,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 List-Id: On Fri, 9 Jun 2023, Richard Sandiford wrote: > guojiufu writes: > > Hi, > > > > On 2023-06-09 16:00, Richard Biener wrote: > >> On Fri, 9 Jun 2023, Jiufu Guo wrote: > >> > >>> Hi, > >>> > >>> As checking the code, there is a "gcc_assert (SCALAR_INT_MODE_P > >>> (mode))" > >>> in "try_const_anchors". > >>> This assert seems correct because the function try_const_anchors cares > >>> about integer values currently, and modes other than SCALAR_INT_MODE_P > >>> are not needed to support. > >>> > >>> This patch makes sure SCALAR_INT_MODE_P when calling > >>> try_const_anchors. > >>> > >>> This patch is raised when drafting below one. > >>> https://gcc.gnu.org/pipermail/gcc-patches/2022-October/603530.html. > >>> With that patch, "{[%1:DI]=0;} stack_tie" with BLKmode runs into > >>> try_const_anchors, and hits the assert/ice. > >>> > >>> Boostrap and regtest pass on ppc64{,le} and x86_64. > >>> Is this ok for trunk? > >> > >> Iff the correct fix at all (how can a CONST_INT have BLKmode?) then > >> I suggest to instead fix try_const_anchors to change > >> > >> /* CONST_INT is used for CC modes, but we should leave those alone. > >> */ > >> if (GET_MODE_CLASS (mode) == MODE_CC) > >> return NULL_RTX; > >> > >> gcc_assert (SCALAR_INT_MODE_P (mode)); > >> > >> to > >> > >> /* CONST_INT is used for CC modes, leave any non-scalar-int mode > >> alone. */ > >> if (!SCALAR_INT_MODE_P (mode)) > >> return NULL_RTX; > >> > > > > This is also able to fix this issue. there is a "Punt on CC modes" > > patch > > to return NULL_RTX in try_const_anchors. > > > >> but as said I wonder how we arrive at a BLKmode CONST_INT and whether > >> we should have fended this off earlier. Can you share more complete > >> RTL of that stack_tie? > > > > > > (insn 15 14 16 3 (parallel [ > > (set (mem/c:BLK (reg/f:DI 1 1) [1 A8]) > > (const_int 0 [0])) > > ]) "/home/guojiufu/temp/gdb.c":13:3 922 {stack_tie} > > (nil)) > > > > It is "set (mem/c:BLK (reg/f:DI 1 1) (const_int 0 [0])". > > I'm not convinced this is correct RTL. (unspec:BLK [(const_int 0)] ...) > would be though. It's arguably more accurate too, since the effect > on the stack locations is unspecified rather than predictable. powerpc seems to be the only port with a stack_tie that's not using an UNSPEC RHS. > Thanks, > Richard