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 [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 365E73858D1E for ; Tue, 31 Jan 2023 08:01:59 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 365E73858D1E Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1675152118; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type; bh=u7VozFY6TpIx/sH0BrU4E+mG1bAJFg1ZQbq8iX2aJgo=; b=XvcPLeEsYqQBW54HweEBQGwiVL/8IFL/YRrSGok3KwOyeJpZ7pnxZ1oAPTdOepei0S/eOm yFWAQw7A2ycGEuw424u6vToXl25KGEMeY4M+a5bfnmpmDGNlRgQNWnoQbECHGh666ZJCzj A/JKnUmMVuWsGdgkgfM+QuLeZu+Qqo8= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-637-s5wnT0jmONi9_gDE7s2aVg-1; Tue, 31 Jan 2023 03:01:57 -0500 X-MC-Unique: s5wnT0jmONi9_gDE7s2aVg-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.rdu2.redhat.com [10.11.54.5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 3CD6E800B30; Tue, 31 Jan 2023 08:01:57 +0000 (UTC) Received: from tucnak.zalov.cz (unknown [10.39.192.223]) by smtp.corp.redhat.com (Postfix) with ESMTPS id EC15A175A2; Tue, 31 Jan 2023 08:01:56 +0000 (UTC) Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.17.1/8.17.1) with ESMTPS id 30V81sFv1011545 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Tue, 31 Jan 2023 09:01:54 +0100 Received: (from jakub@localhost) by tucnak.zalov.cz (8.17.1/8.17.1/Submit) id 30V81r751011544; Tue, 31 Jan 2023 09:01:53 +0100 Date: Tue, 31 Jan 2023 09:01:52 +0100 From: Jakub Jelinek To: Hongtao Liu , Uros Bizjak Cc: gcc-patches@gcc.gnu.org Subject: [PATCH] i386: Fix up ix86_convert_const_wide_int_to_broadcast [PR108599] Message-ID: Reply-To: Jakub Jelinek MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.5 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Spam-Status: No, score=-3.5 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,KAM_SHORT,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,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: Hi! The following testcase is miscompiled. The problem is that during RTL DSE we see a V4DI register is being loaded { 16, 16, 0, 0 } value and DSE mostly works in terms of scalar modes, so it calls movoi to set an OImode REG to (const_wide_int 0x100000000000000010) and ix86_convert_const_wide_int_to_broadcast thinks it can compute that value by broadcasting DImode 0x10. While it is true that for TImode result the broadcast could be used, for OImode/XImode it can't be, because all but the lowest 2 HOST_WIDE_INTs aren't present (so are 0 or -1 depending on sign), not 0x10 in this case. The function checks if the least significant HOST_WIDE_INT elt of the CONST_WIDE_INT is broadcastable from QI/HI/SI/DImode and then /* Check if OP can be broadcasted from VAL. */ for (int i = 1; i < CONST_WIDE_INT_NUNITS (op); i++) if (val != CONST_WIDE_INT_ELT (op, i)) return nullptr; That is needed of course, but nothing checks that CONST_WIDE_INT_NUNITS (op) isn't too small for the mode in question. I think if op would be 0 or -1, it ought to be never CONST_WIDE_INT, but CONST_INT and so we can just punt whenever the number of CONST_WIDE_INT elts is not the expected one. Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? 2023-01-31 Jakub Jelinek PR target/108599 * config/i386/i386-expand.cc (ix86_convert_const_wide_int_to_broadcast): Return nullptr if CONST_WIDE_INT_NUNITS (op) times HOST_BITS_PER_WIDE_INT isn't equal to bitsize of mode. * gcc.target/i386/avx2-pr108599.c: New test. --- gcc/config/i386/i386-expand.cc.jj 2023-01-19 23:22:05.306066616 +0100 +++ gcc/config/i386/i386-expand.cc 2023-01-30 15:33:43.418598714 +0100 @@ -291,7 +291,9 @@ ix86_convert_const_wide_int_to_broadcast broadcast only if vector broadcast is available. */ if (!TARGET_AVX || !CONST_WIDE_INT_P (op) - || standard_sse_constant_p (op, mode)) + || standard_sse_constant_p (op, mode) + || (CONST_WIDE_INT_NUNITS (op) * HOST_BITS_PER_WIDE_INT + != GET_MODE_BITSIZE (mode))) return nullptr; HOST_WIDE_INT val = CONST_WIDE_INT_ELT (op, 0); --- gcc/testsuite/gcc.target/i386/avx2-pr108599.c.jj 2023-01-30 16:04:31.984429702 +0100 +++ gcc/testsuite/gcc.target/i386/avx2-pr108599.c 2023-01-30 16:04:24.459540223 +0100 @@ -0,0 +1,32 @@ +/* PR target/108599 */ +/* { dg-do run { target avx2 } } */ +/* { dg-options "-O2 -mavx2 -mtune=skylake-avx512" } */ + +#include "avx2-check.h" + +struct S { unsigned long long a, b, c, d; }; + +__attribute__((noipa)) void +foo (unsigned long long x, unsigned long long y, + unsigned long long z, unsigned long long w, const struct S s) +{ + if (s.a != x || s.b != y || s.c != z || s.d != w) + abort (); +} + +typedef unsigned long long V __attribute__((may_alias, vector_size (4 * sizeof (unsigned long long)))); + +static void +avx2_test (void) +{ + { + struct S s; + *(V *)&s = (V) { 16, 0, 0, 0 }; + foo (16, 0, 0, 0, s); + } + { + struct S s; + *(V *)&s = (V) { 16, 16, 0, 0 }; + foo (16, 16, 0, 0, s); + } +} Jakub