From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.223.131]) by sourceware.org (Postfix) with ESMTPS id 2AB6A3858C5F for ; Thu, 16 May 2024 11:36:40 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 2AB6A3858C5F Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=suse.de ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 2AB6A3858C5F Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=195.135.223.131 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1715859401; cv=none; b=xTYEs/PTs83MM3HAnbtRzsepzhWMHLRX9PBKUkdExE8HGB7Z8KoiVgBpl3SwE+3dLZdn9dSVjdemtGNG6fJIIE1Kl6TnsF/T69uZfBBIiDlP1nm4ezYOY9G8yBqs+riKvKDxOsSTGJ8xNV16sVVtVQgC+I94Hazyb3cn7jsTWFs= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1715859401; c=relaxed/simple; bh=FyckUgjCGKRWc/KrONdbVmdkhuhxzfgEzUxK62OooSk=; h=DKIM-Signature:DKIM-Signature:DKIM-Signature:DKIM-Signature:Date: From:To:Subject:MIME-Version; b=oC/o/M0DXYYxOGjnsCpZLnTGvKgms2ad4uteOe2f8GjtwKqVonJ7aw1ZkgfW4IcY3IgsdvOQ+yHagK8MunVhJ96OUIVxTMraG3R4zUJnqO18L9xTUzoHkNiOTakdaZ3s32vH0U4hR0Iw7N96MgvK1B9Gu7OlHGdBmL5KAbzlThM= ARC-Authentication-Results: i=1; server2.sourceware.org Received: from murzim.nue2.suse.org (unknown [10.168.4.243]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id D9B615C292 for ; Thu, 16 May 2024 11:36:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1715859399; h=from:from:reply-to:date:date:to:to:cc:mime-version:mime-version: content-type:content-type; bh=xmxrIiDR4xnp2wF6xT3GQ2lDLh+aqOf5eJ3KOjvHmdk=; b=n9O/ag9RqNdIgAL4K8SXZFMZoWBE3Vq6fc1bdFtsV+K7KtFwXRDGvslJt9Q6h0uPNuPH+a I49IeNqm6rP8a9q4LYT49DEIpcBVx4PttXIJp0FypAH84fcK4i+GBlmJ7NzrV5NGlZQ5YH X85ACFvlomNkbRN5nuXzkekda7ovLnM= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1715859399; h=from:from:reply-to:date:date:to:to:cc:mime-version:mime-version: content-type:content-type; bh=xmxrIiDR4xnp2wF6xT3GQ2lDLh+aqOf5eJ3KOjvHmdk=; b=1gL2TOd3iGtNL0yjI1RoI8wxs932N0k3htGglvGV5AXSuZVd+LQMl9L+eWYmXDc7xukg/t FbNdKirI9JiG06BA== Authentication-Results: smtp-out2.suse.de; none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1715859398; h=from:from:reply-to:date:date:to:to:cc:mime-version:mime-version: content-type:content-type; bh=xmxrIiDR4xnp2wF6xT3GQ2lDLh+aqOf5eJ3KOjvHmdk=; b=Sl6be4jec8aVFzZGLSlkxH7eMFmJvB/bqcDl4wAh4H07HihiiGjyUnG2/rn38LOOGVXTDA i+zIFUgHzZqgSVhlBJ+6pGpXW0/fYL83Beo/liuEP23sZ4aaGdi2gscizrsNOct6/OgE6+ EjYlr02tGNN71h6QovIA7TJhK/6P4rA= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1715859398; h=from:from:reply-to:date:date:to:to:cc:mime-version:mime-version: content-type:content-type; bh=xmxrIiDR4xnp2wF6xT3GQ2lDLh+aqOf5eJ3KOjvHmdk=; b=PqKczHFZQTW13AfbcD708ZkDKc/B60e8iVp9QaRj6k7MGPOwDNS44398QQvH91PbDgJGaP Rx5jPJi7cc14TKCA== Date: Thu, 16 May 2024 13:36:38 +0200 (CEST) From: Richard Biener To: gcc-patches@gcc.gnu.org Subject: [PATCH] wrong code with points-to and volatile MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Spam-Score: 0.78 X-Spam-Level: X-Spamd-Result: default: False [0.78 / 50.00]; BAYES_HAM(-3.00)[100.00%]; MISSING_MID(2.50)[]; NEURAL_SPAM_LONG(1.07)[0.305]; NEURAL_SPAM_SHORT(0.31)[0.103]; MIME_GOOD(-0.10)[text/plain]; FUZZY_BLOCKED(0.00)[rspamd.com]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; RCPT_COUNT_ONE(0.00)[1]; ARC_NA(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; RCVD_COUNT_ZERO(0.00)[0]; MISSING_XM_UA(0.00)[]; FROM_EQ_ENVFROM(0.00)[]; TO_DN_NONE(0.00)[]; MIME_TRACE(0.00)[0:+] X-Spam-Status: No, score=-10.5 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,GIT_PATCH_0,MISSING_MID,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: Message-ID: <20240516113638.XVFTxcEE-uaNkSYj0YcoefmWYZLWsxBQLd1SEhitc_c@z> The following fixes points-to analysis which ignores the fact that volatile qualified refs can result in any pointer. Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed. Btw, I noticed this working on ptr-vs-ptr compare simplification using points-to info and running into gcc.c-torture/execute/pr64242.c * tree-ssa-structalias.cc (get_constraint_for_1): For volatile referenced or decls use ANYTHING. * gcc.dg/tree-ssa/alias-38.c: New testcase. --- gcc/testsuite/gcc.dg/tree-ssa/alias-38.c | 14 ++++++++++++++ gcc/tree-ssa-structalias.cc | 7 +++++++ 2 files changed, 21 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/alias-38.c diff --git a/gcc/testsuite/gcc.dg/tree-ssa/alias-38.c b/gcc/testsuite/gcc.dg/tree-ssa/alias-38.c new file mode 100644 index 00000000000..a5c41493473 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/alias-38.c @@ -0,0 +1,14 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-optimized" } */ + +int x; +int y; + +int main () +{ + int *volatile p = &x; + return (p != &y); +} + +/* { dg-final { scan-tree-dump " != &y" "optimized" } } */ +/* { dg-final { scan-tree-dump-not "return 1;" "optimized" } } */ diff --git a/gcc/tree-ssa-structalias.cc b/gcc/tree-ssa-structalias.cc index 9c63305063c..f0454bea2ea 100644 --- a/gcc/tree-ssa-structalias.cc +++ b/gcc/tree-ssa-structalias.cc @@ -3575,6 +3575,10 @@ get_constraint_for_1 (tree t, vec *results, bool address_p, } case tcc_reference: { + if (TREE_THIS_VOLATILE (t)) + /* Fall back to anything. */ + break; + switch (TREE_CODE (t)) { case MEM_REF: @@ -3676,6 +3680,9 @@ get_constraint_for_1 (tree t, vec *results, bool address_p, } case tcc_declaration: { + if (VAR_P (t) && TREE_THIS_VOLATILE (t)) + /* Fall back to anything. */ + break; get_constraint_for_ssa_var (t, results, address_p); return; } -- 2.35.3